U.S. patent application number 15/773459 was filed with the patent office on 2018-11-15 for lens driving device and camera module including same.
The applicant listed for this patent is LG INNOTEK CO., LTD.. Invention is credited to YONG NAM CHOI, SANG YEON HAN, DO YUN KIM, JUNG HWAN KIM.
Application Number | 20180329277 15/773459 |
Document ID | / |
Family ID | 58662297 |
Filed Date | 2018-11-15 |
United States Patent
Application |
20180329277 |
Kind Code |
A1 |
HAN; SANG YEON ; et
al. |
November 15, 2018 |
LENS DRIVING DEVICE AND CAMERA MODULE INCLUDING SAME
Abstract
One embodiment of a camera module comprises: a lens barrel
including at least one lens; a bobbin for accommodating the lens
barrel; and a fixing part disposed between the lens barrel and the
bobbin so as to inhibit the lens barrel from being separated from
the bobbin, wherein one surface, which makes surface contact with
the fixing part, of the bobbin can include a bobbin provided so as
to protrude toward the lens barrel.
Inventors: |
HAN; SANG YEON; (Seoul,
KR) ; KIM; DO YUN; (Seoul, KR) ; KIM; JUNG
HWAN; (Seoul, KR) ; CHOI; YONG NAM; (Seoul,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG INNOTEK CO., LTD. |
Seoul |
|
KR |
|
|
Family ID: |
58662297 |
Appl. No.: |
15/773459 |
Filed: |
November 2, 2016 |
PCT Filed: |
November 2, 2016 |
PCT NO: |
PCT/KR2016/012508 |
371 Date: |
May 3, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G03B 13/36 20130101;
H04N 5/225 20130101; G02B 7/09 20130101; G02B 27/64 20130101; H04N
5/2254 20130101; H02K 33/02 20130101; G03B 3/10 20130101; H04N
5/232 20130101; G03B 17/02 20130101; G03B 43/00 20130101 |
International
Class: |
G03B 13/36 20060101
G03B013/36; G02B 27/64 20060101 G02B027/64; G02B 7/09 20060101
G02B007/09; H04N 5/225 20060101 H04N005/225; H04N 5/232 20060101
H04N005/232 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 4, 2015 |
KR |
10-2015-0154438 |
Dec 8, 2015 |
KR |
10-2015-0173871 |
Dec 24, 2015 |
KR |
10-2015-0185861 |
Jan 15, 2016 |
KR |
10-2016-0005167 |
Claims
1. A camera module comprising: a lens barrel comprising at least
one lens; a bobbin configured to accommodate the lens barrel
therein; and a fixing part disposed between the lens barrel and the
bobbin to inhibit the lens barrel from being separated from the
bobbin, wherein one surface of the bobbin, which is in surface
contact with the fixing part, comprises a bobbin rib provided so as
to protrude toward the lens barrel.
2. The camera module according to claim 1, wherein the bobbin rib
comprises a plurality of bobbin ribs spaced apart from each other
by a constant distance on an inner side surface of the bobbin.
3. The camera module according to claim 1, wherein the bobbin rib
is provided on an inner side surface of the bobbin so as to
protrude.
4. The camera module according to claim 1, wherein the fixing part
comes into contact at one end surface thereof with an inner side
surface of the bobbin, and also comes into contact at a remaining
end surface thereof with an outer side surface of the lens
barrel.
5. The camera module according to claim 1, wherein the lens barrel
comprises a lens barrel rib provided so as to protrude radially
outwards.
6. The camera module according to claim 5, wherein the lens barrel
rib has a sinusoidal cross-sectional shape.
7. The camera module according to claim 1, wherein the lens barrel
comprises a lens barrel recess that is indented radially
outwards.
8. The camera module according to claim 7, wherein the lens barrel
recess has a sinusoidal cross-sectional shape.
9. The camera module according to claim 1, further comprising: a
first coil provided on an outer peripheral surface of the bobbin; a
first magnet disposed so as to face the first coil; a housing
configured to support the first magnet; upper and lower elastic
members coupled to the bobbin and the housing; a base disposed
below the bobbin; a plurality of support members configured to
support the housing so as to be movable in second and third
directions, which are orthogonal to a first direction, relative to
the base; and a printed circuit board seated on the base.
10. The camera module according to claim 1, wherein the fixing part
comprises ultraviolet (UV) curing epoxy.
11. The camera module according to claim 1, wherein the fixing part
comprises thermosetting epoxy.
12. A camera module comprising: a lens barrel comprising at least
one lens; a bobbin configured to accommodate the lens barrel
therein; and a fixing part disposed between the lens barrel and the
bobbin to inhibit the lens barrel from being separated from the
bobbin, wherein one surface of the bobbin, which is in surface
contact with the fixing part, comprises a bobbin rib provided so as
to protrude toward the lens barrel, and wherein one surface of the
lens barrel, which is in surface contact with the fixing part,
comprises a lens barrel rib, which is provided so as to protrude,
or a lens barrel recess, which is provided so as to be
indented.
13. The camera module according to claim 12, wherein the lens
barrel rib or the lens barrel recess has a sinusoidal
cross-sectional shape.
14. The camera module according to claim 12, wherein the fixing
part comprises ultraviolet curing epoxy or thermosetting epoxy.
15. The camera module according to claim 12, wherein the bobbin rib
comprises an inner peripheral surface defining a hollow
cross-sectional shape.
16. A camera module comprising: a lens barrel comprising at least
one lens; a bobbin configured to accommodate the lens barrel
therein; a fixing part disposed between the lens barrel and the
bobbin to inhibit the lens barrel from being separated from the
bobbin; a first coil provided on an outer peripheral surface of the
bobbin; a first magnet disposed so as to face the first coil; a
housing configured to support the first magnet; upper and lower
elastic members coupled to the bobbin and the housing; a base
disposed below the bobbin; a plurality of support members
configured to support the housing so as to be movable in second and
third directions, which are orthogonal to a first direction,
relative to the base; and a printed circuit board seated on the
base, wherein one surface of the bobbin, which is in surface
contact with the fixing part, comprises a bobbin rib provided so as
to protrude toward the lens barrel.
17. The camera module according to claim 16, wherein one surface of
the lens barrel, which is in surface contact with the fixing part,
comprises a lens barrel rib, which is provided so as to protrude,
or a lens barrel recess, which is provided so as to be
indented.
18. The camera module according to claim 16, wherein the lens
barrel rib or the lens barrel recess has a sinusoidal
cross-sectional shape.
19. The camera module according to claim 16, wherein the fixing
part comprises ultraviolet curing epoxy or thermosetting epoxy.
20. The camera module according to claim 16, wherein the fixing
part comes into contact at one end surface thereof with an inner
side surface of the bobbin, and also comes into contact at a
remaining end surface thereof with an outer side surface of the
lens barrel.
Description
TECHNICAL FIELD
[0001] Embodiments relate to a lens driving device and a camera
module including the same.
BACKGROUND ART
[0002] The disclosure described in this part merely provides
background information related to embodiments, and does not
constitute the related art.
[0003] Recently, IT products, such as cellular phones, smartphones,
table PCs, and laptop computers, equipped with subminiature digital
cameras, have been actively developed.
[0004] In the case of a camera module mounted in a small-sized
electronic product such as a smartphone, the camera module may
frequently receive shocks during use, and may shake minutely due
to, for example, shaking of the user's hand. In consideration of
this, development of technology in which a hand-tremor compensation
device is additionally provided to the camera module has recently
been required.
[0005] In order to prevent a camera module from shaking minutely
due to, for example, shaking of the user's hand during image
capturing, an optical module including at least one lens sheet may
be moved in a plane, which is defined by second and third
directions orthogonal to a first direction that is parallel to an
optical axis.
[0006] To this end, the camera module may include a circuit member,
which includes a printed circuit board and at least one second coil
provided on the printed circuit board to provide the force required
to move the optical module in the second and third directions.
[0007] A lens driving device needs to pass a predetermined
standardized shock test once it has been manufactured. The
standardized shock test is generally a test in which, for example,
in the state in which a lens driving device is fixed on a shock
tester table, after shock waves, namely, sine half-waves are
applied three times in two directions orthogonal to each other
about the Z-axis at a maximum shock acceleration of 500 m/s.sup.2
for a shock duration time of 11 ms, it is checked whether the
external appearance of the lens driving device has notable
abnormalities, or whether variation in the specification of the
lens driving device, compared to initial values, is within a
predetermined range.
[0008] In this case, a lens barrel of the lens driving device may
be separated from a bobbin, which accommodates the lens barrel
therein, or may be misaligned.
[0009] During the shock test, as described above, when the lens
barrel is separated from the bobbin or when the lens barrel is
tilted at a predetermined angle, the resolution of a camera module
may be reduced.
[0010] In the case of a lens driving device and a camera module
including the same, which are mounted in a small-sized electronic
product such as a smartphone, an auto-focusing device may be
mounted therein. Specifically, in order to realize auto-focusing, a
bobbin may be mounted in the lens driving device to move a lens in
an optical-axis direction.
[0011] In addition, a lens barrel having a lens may be provided in
the bobbin. The lens barrel may be coupled to the bobbin by
adhesion. Meanwhile, when external shocks are applied to the lens
driving device and the camera module, the coupling of the lens
barrel and the bobbin is broken, so that the lens barrel may move
arbitrarily relative to the bobbin.
[0012] When the lens barrel moves arbitrarily relative to the
bobbin, the lens driving device may not accurately perform a
function thereof such as auto-focusing. Therefore, the quality of
an image captured by the camera module may be reduced.
[0013] The camera module, mounted in the small-sized electronic
product such as a smartphone, may include, for example, the lens
driving device and a holder coupled thereto.
[0014] The lens driving device may include at least one lens, and
may further include an auto-focusing device, which focuses the lens
in an optical-axis direction, and a hand-tremor compensation
device, which prevents deterioration in the quality of an image due
to shaking of the user's hand.
[0015] The holder, which is coupled to the lens driving device, may
include, for example, a sensor holder, on which an image sensor is
mounted so that an image of a subject is formed thereon, and a
filter holder, on which a filter is mounted to filter light within
a specific wavelength range, among the light incident on the image
sensor.
[0016] In the case in which the lens driving device is coupled to
the holder by adhesion, when external force is applied to the lens
driving device and the holder in different directions, shear force
may be applied to the adhered portion of the lens driving device
and the holder.
[0017] When the shear force is repeatedly and continuously applied
to the adhered portion, the adhered portion may be damaged, and in
the worst case, the adhered portion may be broken, causing
separation of the lens driving device and the holder.
[0018] The lens driving device of the camera module is bonded to an
image sensor board using an adhesive containing epoxy.
[0019] In order to align the optical axis of light incident on the
lens driving device with the optical axis of the image sensor
mounted on the image sensor board, when the lens driving device and
the image sensor board are bonded to each other using the adhesive,
a process of aligning the lens driving device and the image sensor
board with each other is performed, and thereafter, the mutual
bonding of the lens driving device and the image sensor board is
performed.
[0020] However, conventionally, when the lens driving device and
the image sensor board are coupled to each other, it is difficult
to handle a flexible circuit board, which protrudes from the lens
driving device and is connected to the image sensor board, which
causes errors in assembly of the flexible circuit board and the
image sensor board and increases the assembly time.
[0021] In addition, when facing portions of the lens driving device
and the image sensor board, which are adhered to each other, are
brought into contact with each other by, for example, a reliability
test, this may greatly deteriorate the performance of the camera
module.
[0022] In addition, due to a narrow adhesion area of the adhesive
disposed between the image sensor board and the lens driving
device, the lens driving device and the image sensor board may be
easily separated from each other by external shocks.
DISCLOSURE
Technical Problem
[0023] Embodiments provide a lens driving device in which a fixing
part is provided between a lens barrel and a bobbin to prevent the
lens barrel from being separated from the bobbin or from tilting
during a shock test, and a camera module including the same.
[0024] In addition, embodiments provide a lens driving device,
which prevents a lens barrel from being separated from a bobbin or
from tilting during a shock test, thereby preventing deterioration
in the resolution of a camera module, and a camera module including
the same.
[0025] In addition, embodiments provide a lens driving device
having a structure that increases the coupling force of a bobbin
and a lens barrel, and a camera module including the same.
[0026] In addition, embodiments provide a camera module having a
firm structure that exerts a high shear strength even when external
force is applied thereto.
[0027] In addition, embodiments provide a camera module in which a
flexible circuit board, which protrudes from a lens driving device
and is connected to an image sensor board, is supported when the
lens driving device and the image sensor board are coupled to each
other, which prevents errors in the assembly of the flexible
circuit board and the image sensor board and reduces the assembly
time.
[0028] In addition, embodiments provide a camera module, which
prevents great deterioration in performance caused when facing
portions of an image sensor board and a lens driving device, which
have been bonded to each other, are brought into contact with each
other by a reliability test or the like.
[0029] In addition, embodiments provide a camera module in which a
lens driving device and an image sensor board are prevented from
being easily separated from each other by external shocks due to a
narrow adhesion area of an adhesive disposed between the image
sensor board and the lens driving device.
[0030] The technical objects acquired by the embodiments are not
limited to the technical objects mentioned above, and other
unmentioned technical objects will be clearly understood by those
skilled in the art from the following description.
Technical Solution
[0031] In one embodiment, a camera module includes a lens barrel
including at least one lens, a bobbin configured to accommodate the
lens barrel therein, and a fixing part disposed between the lens
barrel and the bobbin to prevent the lens barrel from being
separated from the bobbin, wherein one surface of the bobbin, which
is in surface contact with the fixing part, includes a bobbin rib
provided so as to protrude toward the lens barrel.
[0032] In another embodiment, a camera module includes a lens
barrel including at least one lens, a bobbin configured to
accommodate the lens barrel therein, and a fixing part disposed
between the lens barrel and the bobbin to prevent the lens barrel
from being separated from the bobbin, wherein one surface of the
bobbin, which is in surface contact with the fixing part, includes
a bobbin rib provided so as to protrude toward the lens barrel, and
wherein one surface of the lens barrel, which is in surface contact
with the fixing part, includes a lens barrel rib, which is provided
so as to protrude, or a lens barrel recess, which is provided so as
to be indented.
[0033] In a further embodiment, a camera module includes a lens
barrel including at least one lens, a bobbin configured to
accommodate the lens barrel therein, a fixing part disposed between
the lens barrel and the bobbin to prevent the lens barrel from
being separated from the bobbin, a first coil provided on an outer
peripheral surface of the bobbin, a first magnet disposed so as to
face the first coil, a housing configured to support the first
magnet, upper and lower elastic members coupled to the bobbin and
the housing, a base disposed below the bobbin, a plurality of
support members configured to support the housing so as to be
movable in second and third directions, which are orthogonal to a
first direction, relative to the base, and a printed circuit board
seated on the base, wherein one surface of the bobbin, which is in
surface contact with the fixing part, includes a bobbin rib
provided so as to protrude toward the lens barrel.
Advantageous Effects
[0034] A lens driving device and a camera module including the same
according to embodiments may include a fixing part provided between
a lens barrel and a bobbin, thereby being capable of preventing the
lens barrel from being separated from the bobbin or from tilting
during a shock test.
[0035] In addition, by preventing the lens barrel from being
separated from the bobbin or from tilting during a shock test, it
is possible to prevent deterioration in the resolution of a camera
module.
[0036] In the embodiments, by coupling the bobbin and the lens
barrel to each other using a coupling protrusion and a coupling
recess, it is possible to maintain the bobbin and the lens barrel
in the mutually coupled state even when an adhesive, which bonds
the bobbin and the lens barrel to each other, is detached by
external shocks.
[0037] In addition, since the area in which the adhesive is adhered
to the bobbin and the lens barrel may be increased, it is possible
to increase the coupling force of the bobbin and the lens barrel by
the adhesive.
[0038] In addition, since a portion, onto which the adhesive is
applied, has a stepped shape to greatly reduce the formation of a
gap, it is possible to remarkably reduce the amount of adhesive
that moves into the lens driving device through the gap, and thus
to prevent an image sensor and other elements from being damaged by
the adhesive introduced into the lens driving device through the
gap.
[0039] In addition, by limiting excessive movement of the lens
barrel in a first direction due to a first distance smaller than a
second distance, it is possible to prevent or remarkably reduce
deterioration in the quality of a captured image due to arbitrary
uncontrolled movement of the lens barrel.
[0040] In the embodiments, through the provision of a protruding
portion and an indented portion to prevent excessive movement of
the base relative to a filter holder in the x-y plane, it is
possible to prevent a coupling portion from being damaged or broken
by shear force.
[0041] Accordingly, it is possible to prevent deterioration in the
quality of an image captured by the camera module, which may be
caused when the base excessively moves relative to the filter
holder, and to prevent erroneous operation and operation stoppage
of the camera module due to the breakage of the coupling
portion.
[0042] In the embodiments, the protruding portion and the indented
portion corresponding thereto are formed in an adhered portion of
the filter holder and a sensor holder. As such, even when strong
shear force is applied to the adhered portion of the filter holder
and the sensor holder, it is possible to prevent damage to or
breakage of the adhered portion.
[0043] Accordingly, it is possible to prevent deterioration in the
quality of an image, erroneous operation, operation stoppage, or
the like of the camera module due to the breakage of the adhered
portion of the filter holder and the sensor holder.
[0044] In the camera module according to the embodiments, a
flexible circuit board, which protrudes from the lens driving
device and is connected to an image sensor board, is supported when
the lens driving device and the image sensor board are coupled to
each other, whereby it is possible to prevent errors in the
assembly of the flexible circuit board and the image sensor board
and reduce the assembly time.
[0045] In addition, it is possible to prevent great deterioration
in the performance of the camera module caused when facing portions
of the image sensor board and the lens driving device, which have
been bonded to each other, are brought into contact with each other
by a reliability test or the like.
DESCRIPTION OF DRAWINGS
[0046] FIG. 1 is an exploded perspective view schematically
illustrating a camera module according to an embodiment.
[0047] FIGS. 2a and 2b illustrate the state in which a lens barrel
assembly, a sensor base, and a board unit are assembled with each
other according to an embodiment.
[0048] FIG. 3 is a perspective view schematically illustrating a
lens driving device according to an embodiment.
[0049] FIG. 4 is an exploded perspective view illustrating the lens
driving device according to the embodiment.
[0050] FIG. 5 illustrates a base, a printed circuit board, and a
second coil according to an embodiment.
[0051] FIG. 6 illustrates the coupling relationship of a lens
barrel and a bobbin in the lens driving device according to the
embodiment.
[0052] FIG. 7 illustrates an exploded perspective view of the lens
barrel, the bobbin, and a fixing part of the lens driving device
according to another embodiment.
[0053] FIG. 8 illustrates the coupling relationship of the lens
barrel and the bobbin in the lens driving device according to the
embodiment.
[0054] FIG. 9 illustrates various embodiments of region "A"
illustrated in FIG. 8.
[0055] FIG. 10 is a perspective view schematically illustrating a
lens driving device according to still another embodiment.
[0056] FIG. 11 is an exploded perspective view illustrating the
lens driving device according to the embodiment.
[0057] FIG. 12 is a view illustrating a lens barrel according to an
embodiment.
[0058] FIG. 13 is a perspective view illustrating a bobbin
according to an embodiment.
[0059] FIGS. 14 and 15 are views for explaining a method of
coupling the lens barrel to the bobbin, and FIG. 15 illustrates a
coupling recess according to an embodiment.
[0060] FIG. 16 is a cross-sectional view illustrating the state in
which the bobbin and the lens barrel are coupled to each other.
[0061] FIG. 17 is a view illustrating a coupling recess according
to another embodiment.
[0062] FIG. 18 is a view illustrating a coupling recess according
to still another embodiment.
[0063] FIG. 19 is a view illustrating a coupling recess according
to yet another embodiment.
[0064] FIG. 20 is a perspective view illustrating a camera module
according to another embodiment.
[0065] FIG. 21 is an exploded perspective view illustrating a lens
driving device according to still another embodiment.
[0066] FIG. 22 is a perspective view illustrating a base, a filter
holder, and a sensor holder according to an embodiment.
[0067] FIG. 23 is an exploded perspective view illustrating the
base, the filter holder, and the sensor holder according to the
embodiment.
[0068] FIG. 24 is a bottom view illustrating the base according to
an embodiment.
[0069] FIG. 25 is a plan view illustrating the filter holder
according to an embodiment.
[0070] FIG. 26 is a side cross-sectional view illustrating the
state in which the base and the filter holder are coupled to each
other according to an embodiment.
[0071] FIG. 27 is an enlarged view illustrating portion "AA" of
FIG. 26.
[0072] FIG. 28 is a bottom view illustrating the base according to
another embodiment.
[0073] FIG. 29 is a plan view illustrating the filter holder
according to the embodiment.
[0074] FIG. 30 is a bottom view illustrating the filter holder
according to still another embodiment.
[0075] FIG. 31 is a plan view illustrating the sensor holder
according to the embodiment.
[0076] FIG. 32 is an exploded perspective view illustrating a
camera module according to still another embodiment.
[0077] FIG. 33 is an exploded perspective view illustrating a lens
driving device of FIG. 32.
[0078] FIG. 34 is a longitudinal cross-sectional view of the
remainder of the camera module excluding the lens driving device of
FIG. 32.
[0079] FIG. 35 is a cross-sectional view illustrating the bonding
structure of the base corresponding to the holder member according
to an embodiment.
BEST MODE
[0080] Hereinafter, embodiments will be described in detail with
reference to the attached drawings. The embodiments may, however,
be embodied in many alternate forms and the disclosure should not
be construed as limited to the embodiments set forth herein.
Accordingly, while the disclosure is susceptible to various
modifications and alternative forms, specific embodiments thereof
are shown by way of example in the drawings and will herein be
described in detail. It should be understood, however, that there
is no intent to limit the disclosure to the particular forms
disclosed, but on the contrary, the disclosure is to cover all
modifications, equivalents, and alternatives falling within the
spirit and scope of the embodiments as defined by the claims. The
same reference numbers will be used throughout the drawings to
refer to the same or like parts. In the drawings, dimensions of
layers and regions are exaggerated for clarity of description.
[0081] In addition, in the description of the various embodiments,
although terms such as, for example, "first" and "second" may be
used to describe various elements, these terms are merely used to
distinguish the same or similar elements from each other.
Therefore, in the specification, an element modified by "first" may
be the same as an element modified by "second" within the technical
scope of the present invention unless otherwise mentioned.
[0082] In the description of the embodiments, it will be understood
that when an element, such as a layer (film), a region, a pattern
or a structure, is referred to as being "on" or "under" another
element, such as a substrate, a layer (film), a region, a pad or a
pattern, the term "on" or "under" means that the element is
"directly" on or under another element or is "indirectly" formed
such that an intervening element may also be present. In addition,
it will also be understood that the criteria of "on" or "under" is
on the basis of the drawings.
[0083] In addition, relative terms such as, for example,
"on/upper/above" and "beneath/lower/below", used in the following
description may be used to distinguish any one substance or element
with another substance or element without requiring or containing
any physical or logical relationship or sequence between these
substances or elements.
[0084] In addition, a Cartesian coordinate system (x, y, z) may be
used in the drawings. In the drawings, an x axis and a y axis are
directions perpendicular to an optical axis. For convenience, the
optical-axis direction (z-axis direction) may be referred to as a
`first direction`, the x-axis direction may be referred to as a
`second direction`, and the y-axis direction may be referred to as
a `third direction`.
[0085] A "hand-tremor compensation device" used in a small-sized
camera module mounted in a mobile device, such as a smartphone or a
tablet PC, is a device configured to prevent the outline of a
captured image from being blurred due to vibration caused by the
shaking of a user's hand when the image is captured.
[0086] In addition, an "auto-focusing device" is a device for
automatically focusing an image of a subject on the surface of an
image sensor. The hand-tremor compensation device and the
auto-focusing device may be configured in various manners. A lens
driving device according to the embodiments may perform a
hand-tremor compensation operation and/or an auto-focusing
operation with respect to a plane defined by the second and third
directions, which are orthogonal to the first direction, by moving
an optical module constituted by at least one lens in the first
direction, which is parallel to the optical axis.
[0087] FIG. 1 is an exploded perspective view schematically
illustrating a camera module according to an embodiment.
[0088] Referring to FIG. 1, the camera module according to the
embodiment may include a lens barrel 9111 in which a plurality of
lenses are stacked one above another, a bobbin 9110, which
accommodates the lens barrel 9111 therein, a cover member 9300,
which provides an accommodation space in which the bobbin 9110 is
accommodated so that the bobbin 9110 is accommodated therein, a
filter holder 9400, which is provided on the lower surface of the
cover member 9300 and supports the lower surface of the cover
member 9300, an image sensor 9500, which is disposed on one surface
of the filter holder 9400 and converts light incident on the bobbin
9110 into an electrical signal, and a board unit, which provides a
space in which the image sensor 9500 is disposed and transmits the
electrical signal converted by the image sensor 9500 to a
controller (not illustrated) and converts the same.
[0089] The filter holder 9400 may be provided between the lower
surface of the cover member 9300 and the upper surface of the board
unit.
[0090] More specifically, the filter holder 9400 may be adhered to
the lower surface of the cover member 9300 so that the filter
holder 9400 and the cover member 9300 are coupled to each other,
and may be assembled so as to be seated on the upper surface of the
board unit in the state in which the filter holder 9400 and the
cover member 9300 are coupled.
[0091] However, this merely illustrates one embodiment, and a user
may omit the folder holder 9400 and may directly couple the cover
member 9300 to the board unit as needed.
[0092] The filter holder 9400 may include a filter in the center
thereof.
[0093] The filter holder 9400 may be provided in a hollow shape.
This serves to allow light, collected from the outside by the lens
barrel 9111, to pass through the filter holder 9400 to thereby be
transmitted to the image sensor 9500.
[0094] That is, the light, collected from the outside by the lens
barrel 9111, passes through the central portion of the filter
holder 9400. At this time, the filter may be disposed in the center
of the filter holder 9400 to extract only light within a required
wavelength range and transmit the same to the image sensor
9500.
[0095] In an embodiment, the filter may be an infrared (IR) cutoff
filter.
[0096] The outside light collected by the lens barrel 9111 includes
infrared light within a wavelength range invisible to humans. The
IR cutoff filter is a member that blocks light within an infrared
wavelength range in order to prevent the image sensor 9500 from
sensing the infrared light and distorting the actual color to some
other color.
[0097] However, the filter in the embodiment may be a filter that
blocks light within a wavelength range other than an infrared
wavelength range.
[0098] The board unit may include a board base 9610, which provides
one surface on which the bobbin 9110, the cover member 9300, the
filter holder 9400, and the image sensor 9500 are disposed, a
connector unit 9650, which transmits a signal received from the
board base 9610 to the controller (not illustrated), and a
connection board 9630, which has one end electrically connected to
the board base 9610 and the other end electrically connected to the
connector unit 9650, so as to transmit an electrical signal
produced by the board base 9610 to the connector unit 9650.
[0099] The connection board 9630 may be a flexible printed circuit
board (FPCB).
[0100] When the connection board 9630 is a flexible printed circuit
board, the connection board is capable of freely bending unlike an
existing printed circuit board. This enables more efficient
utilization of a limited space.
[0101] However, this has merely been described as one embodiment,
and the connection board 9630 may be a general printed circuit
board, other than the flexible printed circuit board, based on the
needs of the user.
[0102] FIGS. 2a and 2b illustrate the state in which a lens barrel
assembly, a sensor base, and the board unit are assembled with each
other according to an embodiment.
[0103] Referring to FIGS. 2a and 2b, the filter holder 9400, the
image sensor 9500, and the cover member 9300, which accommodates
the bobbin 9110 therein, may be sequentially stacked on the upper
surface of the board base 9610 of the board unit.
[0104] The board base 9610 may include a plurality of terminal
units provided on at least one surface thereof, which is in contact
with the cover member 9300, to electrically connect the board unit
to the image sensor 9500.
[0105] The terminal units may include a first terminal unit 96111
provided along a first side of the lower surface of the cover
member 9300 and a second terminal unit 96113 provided along a
second side, which faces the first side of the lower surface of the
cover member 9300.
[0106] In addition, the terminal units may include an epoxy 9700
provided on a third side, which is adjacent to the first side of
the lower surface of the cover member 9300 on which the first
terminal unit 96111 is disposed, and also provided on a fourth
side, which faces the third side of the lower surface of the cover
member 9300.
[0107] That is, the epoxy 9700 may be disposed on the lower surface
of the cover member 9300, on which no terminal unit is provided.
This serves to prevent an increase in volume caused when the epoxy
9700 is disposed above the terminal units.
[0108] However, the epoxy 9700 and the terminal units may be
disposed at various other positions based on the needs of the user
as long as the image sensor 9500 and the board unit are
electrically connected to each other via the terminal units and as
long as the cover member 9300 and the filter holder 9400 are
physically coupled to each other via the epoxy 9700.
[0109] FIG. 3 illustrates a schematic perspective view of a lens
driving device according to an embodiment, and FIG. 4 illustrates
an exploded perspective view of the lens driving device illustrated
in FIG. 3.
[0110] Referring to FIG. 3, the lens driving device according to
the embodiment may include a first lens driving unit, a second lens
driving unit, and the cover member 9300. Here, the first lens
driving unit may serve as the above-described auto-focusing device,
and the second lens driving unit may serve as the above-described
hand-tremor compensation device.
[0111] The cover member 9300 may have a substantially box shape,
and may surround the first and second lens driving units.
[0112] As illustrated in FIG. 4, the lens driving device according
to the embodiment may include a movable unit. Here, the movable
unit may perform a lens auto-focusing function and a hand-tremor
compensation function. The movable unit may include the bobbin
9110, a first coil 9120, a first magnet 9130, a housing 9140, an
upper elastic member 9150, and a lower elastic member 9160.
[0113] The bobbin 9110 is provided on the outer peripheral surface
thereof with the first coil 9120, which is disposed inside the
first magnet 9130. The bobbin may be provided in the inner space of
the housing 9140 so as to be reciprocatingly movable in the first
direction by electromagnetic interaction between the first magnet
9130 and the first coil 9120. The first coil 9120 may be provided
on the outer peripheral surface of the bobbin 9110 so as to
electromagnetically interact with the first magnet 9130.
[0114] In addition, the bobbin 9110 may be elastically supported by
the upper and lower elastic members 9150 and 9160, and may perform
an auto-focusing function by moving in the first direction.
[0115] The bobbin 9110 may include the lens barrel 9111 in which at
least one lens is provided. The lens barrel 9111 may be coupled
inside the bobbin 9110 in various manners.
[0116] For example, a female screw-thread may be formed in the
inner peripheral surface of the bobbin 9110 and a male screw-thread
may be formed in the outer peripheral surface of the lens barrel
9111 so as to correspond to the female screw-thread, so that the
lens barrel 9111 may be coupled to the bobbin 9110 via screwing.
However, the disclosure is not limited thereto, and instead of
forming the screw-thread in the inner peripheral surface of the
bobbin 9110, the lens barrel 9111 may be directly fixed to the
inner side of the bobbin 9110 by a method other than screwing.
Alternatively, one or more lens sheets may be integrally formed
with the bobbin 9110 without the lens barrel 9111.
[0117] One lens sheet may be coupled to the lens barrel 9111, or
two or more lenses may constitute an optical system.
[0118] The auto-focusing function is controlled based on the
direction of current. The auto-focusing function may be realized
via movement of the bobbin 9110 in the first direction. For
example, when forward current is applied, the bobbin 9110 may move
upwards from the initial position thereof. When reverse current is
applied, the bobbin 9110 may move downwards from the initial
position thereof. Alternatively, the distance of movement in a
given direction from the initial position may be increased or
reduced by adjusting the amount of forward or reverse current.
[0119] The bobbin 9110 may be formed on the upper surface and the
lower surface thereof with a plurality of upper support protrusions
and lower support protrusions. Each of the upper support
protrusions may have a cylindrical shape or a prismatic shape, and
may be coupled and fixed to the upper elastic member 9150. Each of
the lower support protrusions may have a cylindrical shape or a
prismatic shape, similar to the upper support protrusions, and may
be coupled and fixed to the lower elastic member 9160.
[0120] The upper elastic member 9150 may be provided above the
bobbin 9110, and the lower elastic member 9160 may be provided
below the bobbin 9110. Here, the upper elastic member 9150 may be
formed with holes, which correspond to the upper support
protrusions, and the lower elastic member 9160 may be formed with
holes, which correspond to the lower support protrusions. The
respective support protrusions and the respective holes may be
fixedly coupled to each other by thermo-welding or using an
adhesive member such as epoxy.
[0121] The housing 9140 may take the form of a hollow column to
support the first magnet 9130, and may have a substantially square
shape. The first magnet 9130 and a support member 9220 may be
respectively coupled to and disposed on a side surface portion of
the housing 9140.
[0122] In addition, as described above, the bobbin 9110 may be
disposed within the housing 9140 so as to move in the first
direction under the guidance of the elastic members 9150 and 9160.
In the embodiment, the first magnet 9130 may be disposed on a
corner portion of the housing 9140, and the support member 9220 may
be disposed on the side surface of the housing.
[0123] The upper elastic member 9150 and the lower elastic member
9160 may elastically support upward movement and/or downward
movement of the bobbin 9110 in the first direction. The upper
elastic member 9150 and the lower elastic member 9160 may be leaf
springs.
[0124] The upper elastic member 9150, as illustrated in FIG. 2, may
include two members separated from each other. Through the dually
divided structure, the respective divided parts of the upper
elastic member 9150 may receive current having different
polarities, or different voltages. In an alternative embodiment,
the lower elastic member 9160 may have a dually divided structure,
and the upper elastic member 9150 may have an integrated
structure.
[0125] Meanwhile, the upper elastic member 9150, the lower elastic
member 9160, the bobbin 9110, and the housing 9140 may be assembled
by, for example, thermo-welding and/or a bonding operation using an
adhesive or the like. At this time, for example, they are fixed by
thermo-welding, and thereafter, the fixing may be finished by
bonding using an adhesive.
[0126] A base 9210 may be disposed below the bobbin 9110, and may
have a substantially square shape. A printed circuit board 9250 may
be disposed on the base, and the underside of the support member
9220 may be fixed to the base. In addition, the base 9210 may be
formed in the upper surface thereof with a seating recess 9214 for
the support member 9220, so that the support member 9220 may be
inserted into the seating recess. An adhesive may be applied to the
seating recess 9214 for the support member 9220 to immovably fix
the support member 9220.
[0127] The base 9210 may be formed with a support groove in a
portion thereof that faces the portion of the printed circuit board
9250, on which a terminal surface 9253 is formed, the support
groove having a size that corresponds to that of the terminal
surface. The support groove is concavely formed to a predetermined
depth from the outer peripheral surface of the base 9210, thereby
preventing the portion, on which the terminal surface 9253 is
formed, from protruding outwards, or adjusting the extent to which
the portion protrudes.
[0128] The support member 9220 may be disposed on the side surface
of the housing 9140, and may be coupled at the upper side thereof
to the housing 9140 and coupled at the lower side thereof to the
base 9210. The support member may support the bobbin 9110 and the
housing 9140 so as to be movable in the second direction and the
third direction, which are orthogonal to the first direction, and
may be electrically connected to the first coil 9120.
[0129] Since the support member 9220 according to the embodiment is
disposed on each outer side surface of the square of the housing
9140, a total of four support members may be provided in a
symmetrical arrangement. However, the disclosure is not limited
thereto, and a total of eight support members including two
provided for each straight surface may be provided. In addition,
the support member 9220 may be electrically connected to the upper
elastic member 9150, or may be electrically connected to the
straight surface of the upper elastic member 9150.
[0130] In addition, since the support member 9220 is formed
separately from the upper elastic member 9150, the support member
9220 and the upper elastic member 9150 may be electrically
connected to each other using a conductive adhesive, a solder, or
the like. Thus, the upper elastic member 9150 may apply current to
the first coil 9120 via the support member 9220, which is
electrically connected thereto.
[0131] Meanwhile, FIG. 4 illustrates the support member 9220 having
a plate shape by way of example, but the disclosure is not limited
thereto. That is, the support member may have a wire shape.
[0132] A second coil 9230 may move the housing 9140 in the second
direction and/or the third direction via electromagnetic
interaction with the first magnet 9130, thereby being capable of
performing hand-tremor compensation.
[0133] Here, the second and third directions may include not only
the x-axis and y-axis directions but also the directions
substantially close to the x-axis and y-axis directions. That is,
the housing 9140 may move in directions parallel to the x-axis and
the y-axis when viewed in terms of driving in the embodiment, but
may move in directions slightly oblique to the x-axis and the
y-axis when moving while being supported by the support member
9220.
[0134] In addition, it may be necessary to provide the first magnet
9130 at a position that corresponds to the second coil 9230.
[0135] The second coil 9230 may be disposed so as to face the first
magnet 9130 fixed to the housing 9140. In an embodiment, the second
coil 9230 may be disposed outside the first magnet 9130.
Alternatively, the second coil 9230 may be downwardly spaced apart
from the first magnet 9130 by a constant distance.
[0136] According to the embodiment, a total of four second coils
9230 may be provided respectively on four corner portions of a
circuit member 9231, without being limited thereto. Only two second
coils may be provided respectively in the second direction and in
the third direction, or more than four second coils may be
provided.
[0137] In the embodiment, the circuit member 9231 may be formed
with a circuit pattern that takes the form of the second coil 9230,
and a separate second coil may be additionally disposed above the
circuit member 9231, without being limited thereto. Instead of
forming the circuit pattern that takes the form of the second coil
9230, only the second coil 9230 may be separately disposed on the
circuit member 9231 above the circuit member 9231.
[0138] Alternatively, the second coil 9230 may be configured by
winding a wire in a doughnut shape, or may be formed to have an FP
coil shape, so as to be electrically connected to the printed
circuit board 9250.
[0139] The second coil 9230 may be disposed above the base 9210 and
below the housing 9140. Here, the circuit member 9231 including the
second coil 9230 may be provided on the upper surface of the
printed circuit board 9250, which is disposed above the base
9210.
[0140] However, the disclosure is not limited thereto, and the
second coil 9230 may be disposed in close contact with the base
9210 or may be spaced apart from the base by a predetermined
distance. Alternatively, the second coil may be formed on a
separate board so that the board is stacked on and connected to the
printed circuit board 9250.
[0141] The printed circuit board 9250 may be coupled to the upper
surface of the base 9210, and as illustrated in FIG. 4, may be
formed with a hole or a slot at a position that corresponds to the
seating recess 9214 in the support member 9220 so as to expose the
seating groove.
[0142] The printed circuit board 9250 may be formed with the
terminal surface 9253, which is formed by bending, so that a
terminal 9251 is provided on the terminal surface. The embodiment
illustrates the printed circuit board 9250 formed with two bent
terminal surfaces 9253. A plurality of terminals 9251 may be
disposed on each terminal surface 9253 and may supply current to
the first coil 9120 and the second coil upon receiving an external
voltage. The number of terminals formed on the terminal surface
9253 may be increased or reduced based on the constituent elements
that need to be controlled. In addition, the printed circuit board
9250 may include one terminal surface 9253 or three or more
terminal surfaces.
[0143] The cover member 9300 may have a substantially box shape,
may accommodate, for example, the movable unit described above, the
second coil 9230, and a portion of the printed circuit board 9250
therein, and may be coupled to the base 9210. The cover member 9300
may protect, for example, the movable unit, the second coil 9230,
and the printed circuit board 9250, which are accommodated therein,
and more particularly, may limit outward leakage of an
electromagnetic field, which is created by, for example, the first
magnet 9130, the first coil 9120, and the second coil 9230 therein,
thereby enabling the electromagnetic field to be focused.
[0144] FIG. 5 is an exploded perspective view illustrating the base
9210, the printed circuit board 9250, and the second coil 9230
according to an embodiment. The lens driving device may further
include a position sensor 9240.
[0145] The position sensor 9240 may be disposed at the center of
the second coil 9230, and may sense movement of the housing 9140.
Here, the position sensor 9240 may basically sense movement of the
housing 9140 in the first direction, and in some cases, may sense
movement of the housing 9140 in the second and third
directions.
[0146] The position sensor 9240 may be, for example, a hall sensor,
or may be any other sensor as long as it can sense variation in
magnetic force. A total of two position sensors 9240 may be
provided on corner portions of the base 9210, which is disposed
below the printed circuit board 9250, as illustrated in FIG. 5. The
mounted position sensor 9240 may be inserted into and disposed in a
position-sensor seating recess 9215, which is formed in the base
9210. The lower surface of the printed circuit board 9240 may face
the surface on which the second coil 9230 is disposed.
[0147] Meanwhile, the position sensor 9240 may be downwardly spaced
apart from the second coil 9230 by a constant distance with the
printed circuit board 9250 interposed therebetween. That is, the
position sensor 9240 may not be directly connected to the second
coil 9230, the second coil 9230 may be provided on the upper
surface of the printed circuit board 9250, and the position sensor
9240 may be provided on the lower surface of the printed circuit
board.
[0148] Meanwhile, the lens driving device according to the
above-described embodiment may be used in various fields, for
example, a camera module. For example, the camera module may be
applied to a mobile device such as a cellular phone.
[0149] The camera module according to the embodiment may include
the lens barrel 9111 coupled to the bobbin 9110 and the image
sensor 9500. Here, the lens barrel 9111 may include at least one
lens sheet, which transmits an image to the image sensor 9500.
[0150] In addition, the camera module may further include an
infrared cutoff filter (not illustrated). The infrared cutoff
filter serves to prevent light within an infrared range from being
incident on the image sensor 9500.
[0151] In this case, the infrared cutoff filter may be provided on
the base 9210 illustrated in FIG. 3 at a position that corresponds
to the image sensor 9500, and may be coupled to a holder member
(not illustrated). In addition, the holder member may support the
underside of the base 9210.
[0152] The base 9210 may be provided with a terminal member for
electrical conduction with the printed circuit board 9250, and may
also be integrally formed with a terminal using a surface electrode
or the like.
[0153] In addition, the base may further include an adhesive member
9211 for adhering the printed circuit board 9250 to the base
9210.
[0154] The adhesive member 9211 may be provided on one side surface
of the base 9210, and may be provided at a position at which one
side surface of the base 9210 is in surface contact with one side
surface of the printed circuit board 9250, as illustrated in the
drawing.
[0155] In the present embodiment, the adhesive member 9211 is
illustrated as being provided on one surface of the base 9210, but
the adhesive member 9211 may further be provided on a surface that
faces the surface on which the adhesive member 9211 is
provided.
[0156] The adhesive member 9211 illustrated in the present
embodiment is merely given by way of example, and the positions and
number of adhesive members 9211 may be appropriately selected as
long as the printed circuit board 9250 is adhered to the base 9210
by the adhesive members.
[0157] In order to adhere the base 9210 and the printed circuit
board 9250 to each other, the adhesive member 9211 may be provided
on one surface of the base 9210. When the amount of the adhesive
member 9211 is small, adhesion between the base 9210 and the
printed circuit board 9250 may be reduced, which causes separation
of the printed circuit board 9250 from the base 9210. When the
amount of the adhesive member 9211 is large, the adhesive member
9211 may enter the seating recess 9214, which makes it difficult
for the support member 8220 to be accurately coupled to the seating
recess 9214.
[0158] Accordingly, the seating recess 9214 in the base 9210 may
further be provided with a stepped portion in order to prevent the
adhesive member 9211 from entering the seating recess 9214.
[0159] The stepped portion may include at least one side surface
portion 92143, which forms the side surface of the stepped portion,
a lower surface portion 92142, which forms the lower surface of the
stepped portion, and a stepped space 92141, which is defined by the
side surface portion 92143 and the lower surface portion 92142 and
accommodates the adhesive member 9211 therein.
[0160] The cross section of the lower surface portion 92142 of the
stepped space 92141 may be a flat surface shape.
[0161] In addition, the cross section of the lower surface portion
92142 of the stepped space 92141 may have a shape that is convex in
the first direction, which is orthogonal to the lower surface
portion 92142.
[0162] Due to the fact that the cross section of the lower surface
portion 92142 of the stepped space 92141 has a shape that is convex
in the first direction, which is orthogonal to the lower surface
portion 92142, the adhesive member 9211 is gathered to opposite
side surfaces of the lower surface portion 92142, which may more
effectively prevent the adhesive member 9211 from entering the
seating recess 9214.
[0163] In addition, the cross section of the lower surface portion
92142 of the stepped space 92141 may have a shape that is concave
in the first direction, which is orthogonal to the lower surface
portion 92142.
[0164] Due to the fact that the cross section of the lower surface
portion 92142 of the stepped space 92141 has a shape that is
concave in the first direction, which is orthogonal to the lower
surface portion 92142, the adhesive member 9211 is gathered to the
center of the lower surface portion 92142, which may more
effectively prevent the adhesive member 9211 from entering the
seating recess 9214.
[0165] In addition, the cross section of the lower surface portion
92142 of the stepped space 92141 may have a sinusoidal shape.
[0166] Due to the fact that the cross section of the lower surface
portion 92142 of the stepped space 92141 has a sinusoidal shape,
the adhesive member 9211 is gathered to a plurality of indentations
formed in the lower surface portion 92142, which may more
effectively prevent the adhesive member 9211 from entering the
seating recess 9214.
[0167] In addition, one stepped portion is provided in the present
embodiment, but a plurality of stepped portions may be
provided.
[0168] Since, through the provision of the plurality of stepped
portions, a space capable of accommodating the adhesive member 9211
may be doubled or tripled, and therefore, it is possible to more
effectively prevent the adhesive member 9211 from entering the
seating recess 9214.
[0169] The lower surface portion 92142 may further include a
plurality of protruding members 2144.
[0170] The protruding members 2144 may protrude upwards from the
lower surface portion 92142 by a predetermined height.
[0171] The protruding members 2144 provided on the lower surface
portion 92142 may increase resistance to movement of the adhesive
member 9211 introduced into the stepped portion, thereby more
effectively preventing the adhesive member 9211 introduced into the
stepped portion from entering the seating recess 9214.
[0172] The protruding members 2144 are illustrated in the drawing
as having a semispherical shape, but this is merely given by way of
example, and the protruding members 2144 may have a conical shape
or a polygonal shape.
[0173] Meanwhile, the base 9210 may function as a sensor holder to
protect the image sensor. In this case, the base 9210 may be formed
with a protrusion that protrudes downwards along the side surface.
However, this may not be necessary, and although not illustrated, a
separate sensor holder may be disposed below the base 9210 to
perform the role of the protrusion.
[0174] FIG. 6 illustrates the coupling relationship of the lens
barrel and the bobbin in the lens driving device according to the
embodiment.
[0175] Referring to FIG. 6, the lens driving device of the
embodiment may include the lens barrel 9111, which includes at
least one lens, and the bobbin 9110, which provides a space for
accommodating the lens barrel 9111 therein and has a hollow
shape.
[0176] The lens barrel 9111 of the embodiment may be assembled in
the height direction from the upper surface to the lower surface of
the bobbin 9110.
[0177] In order to prevent the lens barrel 9111 from being
separated from the bobbin 9110 in the height direction, or to
prevent the lens barrel 9111 from tilting by a predetermined angle
within the bobbin 9110, the lens driving device of the embodiment
may further include a fixing part 9112 between the lens barrel 9111
and the bobbin 9110.
[0178] The fixing part 9112 may be ultraviolet (UV) curing epoxy
that is cured via radiation of ultraviolet light, or may be
thermosetting epoxy that is cured by radiation of heat.
[0179] The fixing part 9112 of the embodiment may be applied
between the lens barrel 9111 and the bobbin 9110 in the state in
which the lens barrel 9111 is accommodated within the bobbin
9110.
[0180] After the fixing part 9112 is applied between the lens
barrel 9111 and the bobbin 9110, the fixing part 9112 is irradiated
and cured with ultraviolet (UV) light to fix the lens barrel 9111
accommodated within the bobbin 9110, thereby preventing the lens
barrel 9111 from being separated from the bobbin 9110 or from
tilting, which may prevent deterioration in the resolution of the
camera module.
[0181] The lens barrel 9111 of the embodiment may further include a
lens barrel rib 91111, which protrudes from the outer peripheral
surface of the lens barrel 9111 by a predetermined height.
[0182] The upper surface of the lens barrel rib 91111 may be
located lower than the lower surface of the fixing part 9112.
[0183] For example, one end surface of the fixing part 9112 may be
provided so as to be in surface contact with the inner side surface
of the bobbin 9110, and the other end surface of the fixing part
9112 may be provided so as to be in surface contact with the outer
side surface of the lens barrel 9111. The lower surface of the
fixing part 9112 may be provided so as to be in surface contact
with the lens barrel rib 91111.
[0184] When the fixing part 9112 is disposed or applied between the
lens barrel 9111 and the bobbin 9110, the lens barrel rib 91111 may
prevent the fixing part 9112 from deviating downwards from a preset
position, thereby ensuring that the fixing part 9112 is disposed or
applied at a desired position.
[0185] In the case of the lens driving device of the embodiment, in
order to allow the lens barrel 9111 to be inserted into the bobbin
9110, the outer peripheral surface of the lens barrel 9111 may be
spaced apart from the inner peripheral surface of the bobbin 9110
by a predetermined distance, and the fixing part 9112 may be
disposed between the outer peripheral surface of the lens barrel
9111 and the inner peripheral surface of the bobbin 9110.
[0186] However, although the fixing part 9112, which is cured by
ultraviolet light or heat, has predetermined adhesive force, when
the lens driving device of the embodiment undergoes a shock test as
described above, the lens driving device may receive shocks
stronger than the force of adhesion of the fixing part 9112, and
due to this, the lens barrel 9111 inserted into the bobbin 9110 may
be separated from the bobbin 9110, or may tilt within the
bobbin.
[0187] Hereinafter, the lens driving device, which may more
effectively prevent the lens barrel 9111 from being separated from
the bobbin 9110 or from tilting within the bobbin 9110, will be
described with reference to FIGS. 7 to 9.
[0188] FIG. 7 illustrates an exploded perspective view of the lens
barrel, the bobbin, and the fixing part of the lens driving device
according to another embodiment, and FIG. 8 illustrates the
coupling relationship of the lens barrel and the bobbin in the lens
driving device according to the embodiment.
[0189] Referring to FIGS. 7 and 8, the lens driving device of the
embodiment may include the lens barrel 9111, which includes at
least one lens, the bobbin 9110, which provides a space for
accommodating the lens barrel 9111 and has a hollow shape, and the
fixing part 9112 provided between the lens barrel 9111 and the
bobbin 9110 in order to prevent the lens barrel 9111 from being
separated from the bobbin 9110 in the height direction or to
prevent the lens barrel 9111 from tilting by a predetermined angle
within the bobbin 9110.
[0190] The fixing part 9112 may be ultraviolet (UV) curing epoxy
that is cured via irradiation of ultraviolet light, or may be
thermosetting epoxy that is cured by radiation of heat.
[0191] Unlike the lens driving device illustrated in FIG. 6, the
bobbin 9110 may further include a bobbin rib 91101, which protrudes
inwards by a predetermined height, and the fixing part 9112 may
have one end provided so as to be in surface contact with the
bobbin rib 91101 and the other end provided so as to be in surface
contact with the lens barrel 9111.
[0192] When the bobbin rib 91101 protrudes by a predetermined
height from the inner side surface of the bobbin 9110, the bobbin
9110 may apply compressive force to the fixing part 9112, which is
provided so as to be in surface contact with the bobbin rib 91101.
This may allow the lens barrel 9111 to be more effectively fixed
within the bobbin 9110.
[0193] In addition, since the fixing part 9112 may be provided so
as to be in surface contact with both the upper surface and the
lower surface of the bobbin rib 91101, which is provided so as to
protrude inwards, when shocks are applied to the lens driving
device of the embodiment in a direction orthogonal to the upper
surface or the lower surface of the lens barrel 9111 after the
fixing part 9112 is cured, the coupling of the upper surface or the
lower surface of the protruding bobbin rib 91101 and the fixing
part 9112, which is provided so as to be in surface contact with
the upper surface or the lower surface, may provide a more
stabilized structure against external shocks.
[0194] The bobbin rib 91101 may have a strip shape and may be
provided on the inner peripheral surface of the bobbin 9110 to have
a hollow cross-sectional shape as illustrated. Alternatively, a
plurality of bobbin ribs 91101 may be spaced apart from each other
by a predetermined distance on the inner peripheral surface of the
bobbin 9110.
[0195] Although the above-described embodiment illustrates that the
bobbin rib 91101 is provided on the bobbin 9110 so as to protrude
inwards and the outer side surface of the lens barrel 9111 is a
flat surface, unlike this, a lens barrel rib may be provided on the
outer side surface of the lens barrel 9111 so as to protrude
outwards by a predetermined height and the inner side surface of
the bobbin 9110 may be a flat surface.
[0196] In addition to the bobbin 9110, the lens barrel 9111 may
include an additional structure that applies compressive force to
the fixing part 9112. This will be described below with reference
to FIG. 9.
[0197] FIG. 9 illustrates various embodiments of region "A"
illustrated in FIG. 8.
[0198] Referring to FIG. 9, the lens barrel 9111 of the lens
driving device of the embodiment may include the lens barrel rib
91111 (FIG. 9a), which protrudes by a predetermined height to the
outside of the lens barrel 9111, and a lens barrel recess 91112
(FIG. 9b), which is formed to a predetermined depth in the lens
barrel 9111.
[0199] When the lens barrel 9111 includes the lens barrel rib 91111
or the lens barrel recess 91112, it is possible to more effectively
prevent the lens barrel 9111 accommodated within the bobbin 9110
from undergoing predetermined displacement in a direction
orthogonal to the upper surface or the lower surface of the lens
barrel 9111.
[0200] In addition, the lens barrel rib 91111 or the lens barrel
recess 91112 may have a rectangular cross-sectional shape as
illustrated in the drawing, but is not limited thereto, and may be
modified in various manners based on the needs of the user.
[0201] For example, as illustrated in FIG. 9c, the contact surface
of a portion of the lens barrel 9111 that is in surface contact
with the fixing part 9112 may have a sinusoidal shape.
[0202] That is, when the lens barrel 9111 does not have the lens
barrel rib 91111 or the lens barrel recess 91112 described above,
the contact surface of the lens barrel 9111 that is in contact with
the fixing part 9112 may have a sinusoidal shape. When the lens
barrel 9111 has the lens barrel rib 91111 or the lens barrel recess
91112, the contact surface of the lens barrel rib 91111 or the lens
barrel recess 91112 that is in contact with the fixing part 9112
may have a sinusoidal shape.
[0203] This serves to increase the contact area with respect to the
fixing part 9112, thereby allowing the lens barrel 9111 to be more
effectively fixed to the bobbin 9110.
[0204] FIG. 10 is a perspective view schematically illustrating a
lens driving device according to still another embodiment, and FIG.
11 is an exploded perspective view illustrating the lens driving
device according to the embodiment.
[0205] As illustrated in FIG. 11, the lens driving device according
to the embodiment may include a movable unit. Here, the movable
unit may perform a lens auto-focusing function and a hand-tremor
compensation function. The movable unit may include a bobbin 8110,
a first coil 8120, a first magnet 8130, a housing 8140, an upper
elastic member 8150, and a lower elastic member 8160.
[0206] The bobbin 8110 is provided on the outer peripheral surface
thereof with the first coil 8120, which is disposed inside the
first magnet 8130. The bobbin may be provided in the inner space of
the housing 8140 so as to be reciprocatingly movable in the first
direction by electromagnetic interaction between the first magnet
8130 and the first coil 8120. The first coil 8120 may be provided
on the outer peripheral surface of the bobbin 8110 so as to
electromagnetically interact with the first magnet 8130.
[0207] In addition, the bobbin 8110 may be elastically supported by
the upper and lower elastic members 8150 and 9160, and may move in
the first direction to perform an auto-focusing function.
[0208] The bobbin 8110 may include a lens barrel 8400 (see FIG. 12)
in which at least one lens is provided. The lens barrel 8400 may be
coupled inside the bobbin 8110 in various manners.
[0209] For example, a female screw-thread may be formed in the
inner peripheral surface of the bobbin 8110 and a male screw-thread
may be formed in the outer peripheral surface of the lens barrel
8400 so as to correspond to the female screw-thread, so that the
lens barrel 8400 may be coupled to the bobbin 8110 via
screwing.
[0210] However, the disclosure is not limited thereto, and instead
of forming the screw-thread in the inner peripheral surface of the
bobbin 8110, the lens barrel 8400 may be directly fixed to the
inner side of the bobbin 8110 by a method other than screwing.
Alternatively, one or more lens sheets may be integrally formed
with the bobbin 8110 without the lens barrel 8400.
[0211] The auto-focusing function is controlled based on the
direction of current. The auto-focusing function may be realized
via movement of the bobbin 8110 in the first direction. For
example, when forward current is applied, the bobbin 8110 may move
upward from the initial position thereof. When reverse current is
applied, the bobbin 8110 may move downward from the initial
position thereof.
[0212] Alternatively, the distance of movement in a given direction
from the initial position may be increased or reduced by adjusting
the amount of forward or reverse current.
[0213] The bobbin 8110 may be formed on the upper surface and the
lower surface thereof with a plurality of upper support protrusions
and lower support protrusions. Each of the upper support
protrusions may have a cylindrical shape or a prismatic shape, and
may be coupled and fixed to the upper elastic member 8150.
[0214] Each of the lower support protrusions may have a cylindrical
shape or a prismatic shape, similar to the upper support
protrusions, and may be coupled and fixed to the lower elastic
member 8160.
[0215] Here, the upper elastic member 8150 may be formed with
holes, which correspond to the upper support protrusions, and the
lower elastic member 8160 may be formed with holes, which
correspond to the lower support protrusions. The respective support
protrusions and the respective holes may be fixedly coupled to each
other by thermo-welding or using an adhesive member such as
epoxy.
[0216] The housing 8140 may take the form of a hollow column to
support the first magnet 8130, and may have a substantially square
shape. The first magnet 8130 and a support member 8220 may be
respectively coupled to and disposed on a side surface portion of
the housing 8140.
[0217] In addition, as described above, the bobbin 8110 may be
disposed within the housing 8140 so as to move in the first
direction under the guidance of the elastic members 8150 and 8160.
In the embodiment, the first magnet 8130 may be disposed on a
corner portion of the housing 8140, and the support member 8220 may
be disposed on the side surface of the housing.
[0218] The upper elastic member 8150 may be provided above the
bobbin 8110, and the lower elastic member 8160 may be provided
below the bobbin 8110. The upper elastic member 8150 and the lower
elastic member 8160 may elastically support upward movement and/or
downward movement of the bobbin 8110 in the first direction. The
upper elastic member 8150 and the lower elastic member 8160 may be
leaf springs.
[0219] The upper elastic member 8150, as illustrated in FIG. 11,
may include two members separated from each other. Through the
dually divided structure, the respective divided parts of the upper
elastic member 8150 may receive current having different
polarities, or different voltages. In an alternative embodiment,
the lower elastic member 8160 may have a dually divided structure,
and the upper elastic member 8150 may have an integrated
structure.
[0220] Meanwhile, the upper elastic member 8150, the lower elastic
member 8160, the bobbin 8110, and the housing 8140 may be assembled
by, for example, thermo-welding and/or a bonding operation using an
adhesive or the like. At this time, for example, they are fixed by
thermo-welding, and thereafter, the fixing may be finished by
bonding using an adhesive.
[0221] A base 8210 may be disposed below the bobbin 8110, and may
have a substantially square shape. A printed circuit board 8250 may
be disposed on the base, and the underside of the support member
8220 may be fixed to the base. In addition, the base 8210 may be
formed in the upper surface thereof with a seating recess 8214 for
the support member 8220, so that the support member 8220 may be
inserted into the seating recess. An adhesive may be applied to the
seating recess 8214 for the support member 8220 to immovably fix
the support member 8220.
[0222] The base 8210 may be formed with a support groove in a
portion thereof that faces the portion of the printed circuit board
8250, on which a terminal surface 8253 is formed, the support
groove having a size that corresponds to that of the terminal
surface. The support groove is concavely formed to a predetermined
depth from the outer peripheral surface of the base 8210, thereby
preventing the portion, on which the terminal surface 8253 is
formed, from protruding outwards, or adjusting the extent to which
the portion protrudes.
[0223] The support member 8220 may be disposed on the side surface
of the housing 8140, and may be coupled at the upper side thereof
to the housing 8140 and coupled at the lower side thereof to the
base 8210. The support member may support the bobbin 8110 and the
housing 8140 so as to be movable in the second direction and the
third direction, which are orthogonal to the first direction, and
may be electrically connected to the first coil 8120.
[0224] Since the support member 8220 according to the embodiment is
disposed on each outer side surface of the square of the housing
8140, a total of four support members may be provided in a
symmetrical arrangement. However, the disclosure is not limited
thereto, and a total of eight support members including two
provided for each straight surface may be provided.
[0225] In addition, the support member 8220 may be electrically
connected to the upper elastic member 8150, or may be electrically
connected to the straight surface of the upper elastic member
8150.
[0226] In addition, since the support member 8220 is formed
separately from the upper elastic member 8150, the support member
8220 and the upper elastic member 8150 may be electrically
connected to each other using a conductive adhesive, a solder, or
the like. Thus, the upper elastic member 8150 may apply current to
the first coil 8120 via the support member 8220, which is
electrically connected thereto.
[0227] Meanwhile, FIG. 11 illustrates the support member 8220
having a plate shape by way of example, but the disclosure is not
limited thereto. That is, the support member may have a wire
shape.
[0228] A second coil 8230 may move the housing 8140 in the second
direction and/or the third direction via electromagnetic
interaction with the first magnet 8130, thereby being capable of
performing hand-tremor compensation.
[0229] Here, the second and third directions may include not only
the x-axis and y-axis directions but also the directions
substantially close to the x-axis and y-axis directions. That is,
the housing 8140 may move in directions parallel to the x-axis and
the y-axis when viewed in terms of driving in the embodiment, but
may move in directions slightly oblique to the x-axis and the
y-axis when moving while being supported by the support member
8220.
[0230] In addition, it may be necessary to provide the first magnet
8130 at a position that corresponds to the second coil 8230.
[0231] The second coil 8230 may be disposed so as to oppose to the
first magnet 8130 fixed to the housing 8140. In an embodiment, the
second coil 8230 may be disposed outside the first magnet 8130.
Alternatively, the second coil 8230 may be downwardly spaced apart
from the first magnet 8130 by a constant distance.
[0232] According to the embodiment, a total of four second coils
8230 may be provided respectively on four corner portions of a
circuit member 8231, without being limited thereto. Only two second
coils may be provided respectively in the second direction and in
the third direction, or more than four second coils may be
provided.
[0233] In the embodiment, the circuit member 8231 may be formed
with a circuit pattern that takes the form of the second coil 8230,
and a separate second coil may be additionally disposed above the
circuit member 8231, without being limited thereto. Instead of
forming the circuit pattern that takes the form of the second coil
8230, only the second coil 8230 may be separately disposed on the
circuit member 8231 above the circuit member 8231.
[0234] Alternatively, the second coil 8230 may be configured by
winding a wire in a doughnut shape, or may be formed to have an FP
coil shape, so as to be electrically connected to the printed
circuit board 8250.
[0235] The second coil 8230 may be disposed above the base 8210 and
below the housing 8140. Here, the circuit member 8231 including the
second coil 8230 may be provided on the upper surface of the
printed circuit board 8250, which is disposed above the base
8210.
[0236] However, the disclosure is not limited thereto, and the
second coil 8230 may be disposed in close contact with the base
8210, may be spaced apart from the base by a predetermined
distance, or may be formed on a separate board so that the board
may be stacked on and connected to the printed circuit board
8250.
[0237] The printed circuit board 8250 may be coupled to the upper
surface of the base 8210, and as illustrated in FIG. 11, may be
formed with a hole or a slot at a position that corresponds to the
seating recess 8214 in the support member 8220 so as to expose the
seating groove.
[0238] The printed circuit board 8250 may be formed with the
terminal surface 8253, which is formed by bending, so that a
terminal 8251 is provided on the terminal surface. The embodiment
illustrates the printed circuit board 8250 formed with two bent
terminal surfaces 8253. A plurality of terminals 8251 may be
disposed on each terminal surface 8253 and may supply current to
the first coil 8120 and the second coil upon receiving an external
voltage.
[0239] The number of terminals formed on the terminal surface 8253
may be increased or reduced based on the constituent elements that
need to be controlled. In addition, the printed circuit board 8250
may include one terminal surface 8253, or three or more terminal
surfaces.
[0240] The cover member 8300 may have a substantially box shape,
may accommodate, for example, the movable unit described above, the
second coil 8230, and a portion of the printed circuit board 8250
therein, and may be coupled to the base 8210.
[0241] The cover member 8300 may protect, for example, the movable
unit, the second coil 8230, and the printed circuit board 8250,
which are accommodated therein, and more particularly, may limit
outward leakage of an electromagnetic field, which is created by
the first magnet 8130, the first coil 8120, the second coil 8230,
and the like therein, thereby enabling the electromagnetic field to
be focused.
[0242] FIG. 12 is a view illustrating the lens barrel 8400
according to an embodiment. One lens sheet may be coupled to the
lens barrel 8400, or two or more lenses may constitute an optical
system.
[0243] The lens barrel 8400 may include a coupling protrusion 84100
and a slope 84200. At least one coupling protrusion 84100 may be
formed on the outer peripheral surface of the lens barrel 8400, and
may be inserted into a coupling recess 81100 formed in the bobbin
8110, which will be described below.
[0244] In order to increase the coupling force of the bobbin 8110
and the lens barrel 8400, a plurality of coupling protrusions 84100
may be provided. For example, as illustrated in FIG. 12, a pair of
coupling protrusions may be formed on the outer peripheral surface
of the lens barrel 8400 at positions symmetrical to each other
about the center of the lens barrel 8400.
[0245] The coupling protrusion 84100 is coupled to the coupling
recess 81100 to couple the bobbin 8110 and the lens barrel 8400 to
each other, thereby increasing the coupling force of the bobbin
8110 and the lens barrel 8400. As such, the coupling protrusion
serves to prevent the lens barrel 8400 from being separated from
the bobbin 8110 even when external shocks are applied to the lens
driving device.
[0246] Therefore, more than three coupling protrusions 84100 may be
provided on the outer peripheral surface of the lens barrel 8400 in
order to further increase the coupling force of the bobbin 8110 and
the lens barrel 8400.
[0247] In addition, there is a need to prevent external shocks from
being concentrated on a specific portion of the bobbin 8110 or the
lens barrel 8400. To this end, the coupling protrusions 84100 may
need to be spaced apart from each other by a constant distance in
the circumferential direction on the outer peripheral surface of
the lens barrel 8400.
[0248] Since the coupling protrusions 84100 are symmetrically or
radially disposed about the center of the lens barrel 8400 in the
case in which the coupling protrusions 84100 are disposed to have
the structure described above, when external shocks are applied, it
is possible to prevent external shocks from being concentrated on a
specific portion of the lens barrel 8400 or the coupling
protrusions 84100.
[0249] Meanwhile, in the case in which the plurality of coupling
protrusions 84100 are provided on the outer peripheral surface of
the lens barrel 8400, the number of coupling recesses 81100, which
will be described below, may be the same as the number of coupling
protrusions 84100, and may be disposed at positions that correspond
to the coupling protrusions 84100.
[0250] The slope 84200, as illustrated in FIG. 12, may be formed on
the outer peripheral surface of the lens barrel 8400 above the
coupling protrusions 84100 when viewing the drawing. The slope
84200 may be formed at a position that faces a stepped portion
81200, which will be described below, in the first direction.
[0251] When the slope 84200 and the stepped portion 81200 are
disposed at positions that face each other and are adhered to each
other using an adhesive g, the bobbin 8110 and the lens barrel 8400
may be coupled to each other using the adhesive g. The structure in
which the slope 84200 and the stepped portion 81200 are coupled to
each other using the adhesive g will be described below in detail.
Meanwhile, the adhesive g may be, for example, epoxy or a
thermosetting material.
[0252] FIG. 13 is a perspective view illustrating the bobbin 8110
according to an embodiment. As illustrated in FIG. 13, the bobbin
8110 of the embodiment may include the coupling recess 81100 and
the stepped portion 81200. The coupling recess 81100 may be formed
in the inner peripheral surface of the bobbin 8110, and may be
provided in the same number as that of the coupling protrusions
84100. The coupling recess is a portion into which the coupling
protrusion 84100 is inserted.
[0253] As described above, when the coupling protrusion 84100 is
inserted into the coupling recess 81100 so that the bobbin 8110 and
the lens barrel 8400 are coupled to each other, this may increase
the coupling force between the bobbin 8110 and the lens barrel
8400.
[0254] The coupling recess 81100 may be provided in a number and
position that correspond to the number and position of the coupling
protrusion 84100. Thus, in the case in which the plurality of
coupling protrusions 84100 are provided and the coupling
protrusions 84100 are symmetrically or radially disposed about the
lens barrel 8400, a plurality of coupling recesses 81100 may be
symmetrically or radially formed in the inner peripheral surface of
the bobbin 8110 about the center of the bobbin 8110.
[0255] As illustrated in FIG. 13, the coupling recess 81100 may
include a first recess 81110 and a second recess 81120. The first
recess 81110 may be formed in the first direction in the inner
peripheral surface of the bobbin 8110. The second recess 81120 may
be connected to the first recess 81110, and may be formed in the
circumferential direction in the inner peripheral surface of the
bobbin 8110.
[0256] The first recess 81110 is a portion in which the coupling
protrusion 84100 is inserted into the coupling recess 81100. Thus,
the first recess 81110 may be formed in the lower surface thereof
with an opening p so that the coupling protrusion 84100 is inserted
into the opening, when viewing the drawing.
[0257] The second recess 81120 is a portion in which the coupling
protrusion 84100 inserted through the first recess 81110 is seated
in the coupling recess 81100. That is, the coupling protrusion
84100 may be inserted into the first recess 81110, and thereafter
may be rotated via rotation of the bobbin 8110 so as to be seated
in the second recess 81120. The method of coupling the coupling
protrusion 84100 into the coupling recess 81100 will be described
below in detail with reference to the drawings.
[0258] Meanwhile, the coupling recess 81100 may be formed by
removing a portion of the inner peripheral surface of the bobbin
8110, or by injection molding. The portion of the bobbin 8110 in
which the coupling recess 81100 is formed may be reduced in
thickness. Due to this, since the strength of the entire bobbin
8110 may be reduced, in order to prevent this, the coupling recess
81100 may be appropriately formed in a specific portion of the
bobbin 8110 having a larger thickness.
[0259] In addition, in order to prevent deterioration in the
strength of the bobbin 8110 due to the formation of the coupling
recess 81100, the bobbin 8110 may be increased in thickness in the
portion thereof in which the coupling recess 81100 is formed. That
is, the shape of the portion of the bobbin 8110 may be changed so
that the portion in which the coupling recess 81100 is formed is
thicker than the remainder thereof.
[0260] The stepped portion 81200, as illustrated in FIG. 13, may be
disposed above the coupling recess 81100, when viewing the drawing.
That is, the coupling recess 81100 may be disposed below the
stepped portion 81200, and the first recess 81110 may have the
opening g formed in the lower surface of the bobbin 8110.
[0261] The stepped portion 81200 takes the form of a ring that
protrudes in the circumferential direction from the inner
peripheral surface of the bobbin 8110, and a portion of the
adhesive g that couples the lens barrel 8400 and the bobbin 8110 to
each other may be adhered to a part of the stepped portion.
[0262] The stepped portion 81200 may serve as follows, for example.
First, the stepped portion 81200 may increase the area of an
adhered portion of the adhesive g to increase the coupling force of
the bobbin 8110 and the lens barrel 8400.
[0263] In addition, since it is possible to increase the area of an
adhered portion of the adhesive g, the adhesive g may maintain
sufficient adhesive force for the bobbin 8110. Thus, even when
external shocks are continuously applied to the lens driving
device, the adhesive g may not be easily detached from the bobbin
8110.
[0264] In addition, as described above, since the stepped portion
81200 is disposed so as to face the slope 84200 in the first
direction, the size of a gap between the stepped portion 81200 and
the slope 84200 may be remarkably reduced. Therefore, it is
possible to prevent or remarkably reduce damage to respective
constituent elements including the image sensor (not illustrated),
which occurs when the adhesive g that is not yet cured is
introduced into the underside of the lens driving device through
the gap.
[0265] In addition, the stepped portion 81200 may serve as a
stopper of the lens barrel 8400. That is, when the adhesive g,
which couples the lens barrel 8400 and the bobbin 8110 to each
other, is detached due to external shocks continuously applied to
the lens driving device, the stepped portion may prevent the lens
barrel 8400 from being excessively separated from the bobbin
8110.
[0266] That is, the stepped portion 81200 is disposed so as to face
the slope 84200 in the first direction, and a first distance d1,
which is measured as a first direction distance between the stepped
portion 81200 and the slope 84200, is very small.
[0267] Thus, through the structure described above, even if the
adhesive g is detached, the stepped portion 81200 may prevent the
lens barrel 8400 from being excessively separated upward in the
first direction from the bobbin 8110. The role of the stepped
portion 81200 as the stopper will be concretely described below
with reference to the drawings.
[0268] FIGS. 14 and 15 are views for explaining a method of
coupling the lens barrel 8400 to the bobbin 8100. Here, FIG. 15
illustrates the coupling recess 81100 according to an
embodiment.
[0269] The lens barrel 8400 may be coupled to the bobbin 8110 by
the following method. First, the lens barrel 8400 is inserted in
the first direction from the lower side of the bobbin 8110. At this
time, the positions of the coupling protrusion 84100 and the first
recess 81110 are aligned with each other so as to enable the
coupling protrusion 84100 to be inserted into the first recess
81110.
[0270] Subsequently, the coupling protrusion 84100 is inserted into
the first recess 81110 of the coupling recess 81100 through the
opening g in the first recess 81110. The lens barrel 8400 is
continuously pushed upward in the first direction until the
coupling protrusion 84100 reaches the second recess 81120.
[0271] Subsequently, once the coupling protrusion 84100 has reached
the position of the second recess 81120, the lens barrel 8400 is
rotated in a given direction relative to the bobbin 8110 about the
first direction so as to be farther away from the connection region
of the first recess 81110 and the second recess 81120.
[0272] At this time, after being inserted into the first recess
81110 in the first direction, the coupling protrusion 84100 may be
rotated about the first direction and inserted into the second
recess 81120 so as to be seated in the second recess 81120.
[0273] Meanwhile, in order to enable the coupling protrusion 84100
to be smoothly coupled into the coupling protrusion 84100, the
width of the first recess 81110 and the width w of the second
recess 81120 may be larger than the diameter D of the coupling
protrusion 84100.
[0274] As the coupling protrusion 84100 is seated in the second
recess 81120 of the coupling recess 81100 through the
above-described process, the lens barrel 8400 may be coupled to the
bobbin 8110.
[0275] With the structure described above, in the embodiment, by
coupling the bobbin 8110 and the lens barrel 8400 to each other
using the coupling protrusion 84100 and the coupling recess 81100,
the bobbin 8110 and the lens barrel 8400 may remain in the coupled
state even when the adhesive g, which couples the bobbin 8110 and
the lens barrel 8400 to each other, is detached due to external
shocks.
[0276] At this time, the coupled lens barrel 8400 may move slightly
in the first direction relative to the bobbin 8110. Therefore, by
again coupling the bobbin 8110 and the lens barrel 8400 to each
other using the adhesive g, it is possible to prevent the lens
barrel 8400 from moving in the first direction relative to the
bobbin 8100. Hereinafter, the coupling structure of the bobbin 8110
and the lens barrel 8400 using the adhesive g will be
described.
[0277] FIG. 16 is a cross-sectional view illustrating the state in
which the bobbin 8110 and the lens barrel 8400 are coupled to each
other. As illustrated in FIG. 16, the stepped portion 81200 may be
disposed at a position at which it faces the slope 84200, which is
formed on the outer peripheral surface of the lens barrel 8400, in
the first direction.
[0278] In the structure described above, the adhesive g may be
applied to both the stepped portion 81200 and the slope 84200 so as
to allow the upper surface and the side surface of the stepped
portion 81200 to be coupled to the slope 84200. Since the applied
adhesive g is movable before being cured, a part of the adhesive g
may be introduced into the lower portion of the stepped portion
81200 through the gap between the stepped portion 81200 and the
slope 84200.
[0279] A part of the adhesive g, which has been introduced into the
lower portion of the stepped portion 81200 through the gap, is
cured, thus serving to increase the adhesive area between the
bobbin 8110 and the lens barrel 8400. In addition, since the gap is
formed to have a very small size due to the presence of the stepped
portion 81200, it is possible to prevent excessive adhesive g from
being introduced into the lens driving device through the gap.
[0280] With the structure described above, in the embodiment, the
adhesive g may increase the coupling area between the bobbin 8110
and the lens barrel 8400, and consequently, may increase the
coupling force of the bobbin 8110 and the lens barrel 8400.
[0281] In addition, since the gap is formed in a portion, on which
the adhesive g is applied, to have a very small size due to the
stepped portion 81200, it is possible to remarkably reduce the
amount of the adhesive g that moves into the lens driving device
through the gap, and thus, to prevent damage to the image sensor
and other elements by the adhesive g introduced into the lens
driving device through the gap.
[0282] Hereinafter, the role of the stepped portion 81200 as a
stopper for the lens barrel 8400 will be described with reference
to FIGS. 15 and 16. As illustrated in FIG. 16, the first distance
d1 may be measured as the first direction distance between the
stepped portion 81200 and the slope 84200.
[0283] Meanwhile, referring to FIG. 15, a second distance d2 may be
calculated using the following Equation.
d2=w-D Equation 1
[0284] That is, the second distance d2 may be taken as the
difference between the width w of the second recess 81120 and the
diameter D of the coupling protrusion 84100.
[0285] In the embodiment, the first distance d1 may be smaller than
the second distance d2. With this structure, when the adhesive g is
detached due to external shocks, the stepped portion 81200 may
effectively serve as a stopper for the lens barrel 8400.
[0286] That is, when the cured adhesive g is detached rather than
being adhered to the bobbin 8110 and the lens barrel 8400 due to
external shocks applied to the lens driving device, the lens barrel
8400 may move in the first direction relative to the bobbin 8110,
and the maximum movable width may correspond to the second distance
d2.
[0287] The width w of the second recess 81120 may be somewhat large
in order to allow the coupling protrusion 84100 to be smoothly
coupled into the coupling recess 81100. When the width w of the
second recess 81120 is larger than the diameter D of the coupling
protrusion 84100, the second distance d2 may correspondingly
increase.
[0288] In the case in which the second distance d2 is excessively
large, the lens barrel 8400 may excessively move in the first
direction relative to the bobbin 8110 when the adhesive g is
detached. When the lens barrel 8400 excessively moves in the first
direction, for example, the auto-focusing function of the lens
driving device may not be efficiently exerted.
[0289] Accordingly, due to erroneous operation of the auto-focusing
function, the quality of an image captured by a camera module
including the lens driving device may be remarkably deteriorated.
Therefore, when the adhesive g is detached, it is necessary to
prevent the lens barrel 8400 from excessively moving in the first
direction.
[0290] In the embodiment, since the first distance d1 is smaller
than the second distance d2, the distance by which the lens barrel
8400 may move upwards in the first direction may be smaller than
the second distance d2. This is because the stepped portion 81200
limits the distance by which the lens barrel 8400 moves upwards in
the first direction.
[0291] In the embodiment, since the first distance d1 is smaller
than the second distance d2 to prevent the lens barrel 8400 from
excessively moving in the first direction, it is possible to
prevent or remarkably reduce deterioration in the quality of a
captured image due to arbitrary uncontrolled movement of the lens
barrel 8400.
[0292] Meanwhile, a separate stopper may be provided on the bobbin
8110 or the lens barrel 8400 in order to limit the distance by
which the lens barrel 8400 moves downward in the first
direction.
[0293] FIG. 17 is a view illustrating the coupling recess 81100
according to another embodiment. As illustrated in FIG. 17, in the
coupling recess 81100 of the embodiment, a portion of the second
recess 81120 that is connected to the first recess 81110 has a
first width w1 larger than a second width w2 of an end of the first
recess 81110, which is spaced apart from the connection portion. In
addition, the second width w2 may be equal to or less than the
diameter D of the coupling protrusion 84100.
[0294] With the structure described above, when the coupling
protrusion 84100 has been completely seated in the coupling recess
81100, the coupling protrusion may be tightly coupled into the
second recess 81120. In this structure, even when the adhesive g is
detached due to repeatedly applied external shocks, the coupling
protrusion may remain tightly coupled into the second recess
81120.
[0295] Thus, even when the adhesive g is detached, it is possible
to prevent or remarkably reduce deterioration in the quality of an
image due to arbitrary uncontrolled movement of the lens barrel
8400 in the first direction relative to the bobbin 8110.
[0296] FIG. 18 is a view illustrating the coupling recess 81100
according to still another embodiment. In the embodiment, the first
recess 81110 of the coupling recess 81100 may have an opening p,
which is formed in the upper surface of the bobbin 8110. In this
structure, when the lens barrel 8400 is coupled to the bobbin 8110,
the lens barrel 8400 may be inserted in the first direction from
the upper side of the bobbin 8110.
[0297] In addition, in the embodiment of FIG. 18, as illustrated in
FIG. 18, the stepped portion 81200 may be formed in a portion,
excluding the portion in which the first recess 81110 is formed, at
a position similar to that of the stepped portion 81200 illustrated
in FIG. 17. Alternatively, the stepped portion 81200 illustrated in
FIG. 17 may not be formed.
[0298] In the embodiment of FIG. 18, when the stepped portion 81200
is not formed, the adhesive g may be applied to the inner
peripheral surface of the bobbin 8110 at an appropriate position
above the second recess 81120 to adhere the bobbin 8110 and the
lens barrel 8400 to each other.
[0299] In addition, in the embodiment of FIG. 18, when the stepped
portion 81200 is formed, the adhesive g may be applied to the upper
surface of the stepped portion 81200 to adhere the bobbin 8110 and
the lens barrel 8400 to each other.
[0300] In the embodiment of FIG. 18, regardless of whether or not
the stepped portion 81200 is formed, in order to minimize the
introduction of the adhesive g into the lens driving device, the
adhesive g may be adhered to the slope 84200 of the lens barrel
8400.
[0301] FIG. 19 is a view illustrating the coupling recess 81100
according to yet another embodiment. As illustrated in FIG. 19, the
first recess 81110 of the coupling recess 81100 may have the
opening p formed in the upper surface of the bobbin 8110.
[0302] In addition, a portion of the second recess 81120 that is
connected to the first recess 81110 may have a first width w1
larger than a second width w2 of an end of the first recess 81110
that is spaced apart from the connection portion. In addition, the
second width w2 may be equal to or less than the diameter D of the
coupling protrusion 84100.
[0303] With the structure described above, when the coupling
protrusion 84100 has been completely seated in the coupling recess
81100, the coupling protrusion may be tightly coupled into the
second recess 81120.
[0304] In addition, as described above, in this structure, even
when the adhesive g is detached due to repeatedly applied external
shocks, the coupling protrusion may remain tightly coupled into the
second recess 81120.
[0305] Thus, even when the adhesive g is detached, it is possible
to prevent or remarkably reduce deterioration in the quality of an
image due to arbitrary uncontrolled movement of the lens barrel
8400 in the first direction relative to the bobbin 8110.
[0306] Meanwhile, the lens driving device according to the
above-described embodiment may be used in various fields, for
example, a camera module. For example, the camera module may be
applied to a mobile device such as a cellular phone.
[0307] The camera module according to the embodiment may include
the lens barrel 8400 coupled to the bobbin 8110 and an image sensor
(not illustrated). Here, the lens barrel 8400 may include at least
one lens sheet, which transmits an image to the image sensor.
[0308] In addition, the camera module may further include an
infrared cutoff filter (not illustrated). The infrared cutoff
filter serves to prevent light within an infrared range from being
incident on the image sensor.
[0309] In this case, the infrared cutoff filter may be provided on
the base 8210 illustrated in FIG. 11 at a position that corresponds
to the image sensor, and may be coupled to a holder member (not
illustrated). In addition, the holder member may support the
underside of the base 8210.
[0310] The base 8210 may be provided with a terminal member for
electrical conduction with the printed circuit board 8250, and may
also be integrally formed with a terminal using a surface electrode
or the like.
[0311] Meanwhile, the base 8210 may function as a sensor holder to
protect the image sensor. In this case, the base 8210 may be formed
with a protrusion that protrudes downward along the side surface.
However, this may not be necessary, and although not illustrated, a
separate sensor holder may be disposed below the base 8210 to
perform the role of the protrusion.
[0312] FIG. 20 is a perspective view illustrating a camera module
according to another embodiment. FIG. 21 is an exploded perspective
view illustrating a lens driving device 7100 according to still
another embodiment.
[0313] As illustrated in FIG. 20, the camera module according to
the embodiment may include the lens driving device 7100, a filter
holder 7400, and a sensor holder 7500.
[0314] The lens driving device 7100 may include a base 7210, which
is disposed in the lower portion thereof and is adhered to the
filter holder 7400. The lens driving device 7100, as described
above, may perform a hand-tremor compensation operation and/or an
auto-focusing operation by moving an optical module constituted by
a plurality of lenses. The concrete structure of the lens driving
device 7100 will be described below with reference to FIG. 21.
[0315] The filter holder 7400 may be adhered to the base 7210, and
a filter 7410 may be mounted on the filter holder. The sensor
holder 7500 may be disposed below the filter holder 7400, and may
be configured as a circuit board on which an image sensor 7510 is
mounted.
[0316] In addition to the image sensor 7510, the sensor holder 7500
may include various drivers for driving the lens driving device
7100 and circuits for receiving current or receiving or
transmitting electrical signals from or to external devices.
[0317] Thus, the sensor holder 7500 may be a circuit board. In
addition, a connection board 7600 may be coupled to the sensor
holder 7500 for electrical connection between the sensor holder
7500 and an external device such as, for example, a power supply, a
display device, or a storage device.
[0318] The filter holder 7400 and the sensor holder 7500 will be
described below in detail with reference to FIG. 22 and the
following drawings.
[0319] As illustrated in FIG. 21, the lens driving device 7100
according to the embodiment may include a movable unit and a fixing
part. Here, the movable unit may perform an auto-focusing function.
The movable unit may include a bobbin 7110 and a first coil 7120,
and the fixing part may include a first magnet 7130, a housing
7140, an upper elastic member 7150, and a lower elastic member
7160.
[0320] The bobbin 7110 may be provided inside the housing 7140 so
as to move in the first direction, may include the first coil 7120
provided on the outer peripheral surface thereof so as to be
disposed inside the first magnet 7130, and may be provided in the
inner space of the housing 7140 so as to be reciprocatingly movable
in the first direction by electromagnetic interaction between the
first magnet 7130 and the first coil 7120. The first coil 7120 may
be provided on the outer peripheral surface of the bobbin 7110 so
as to electromagnetically interact with the first magnet 7130.
[0321] In addition, the bobbin 7110 may be elastically supported by
the upper and lower elastic members 7150 and 7160, and may perform
an auto-focusing function by moving in the first direction.
[0322] The bobbin 7110 may include a lens barrel (not illustrated)
in which at least one lens is provided. The lens barrel may be
coupled inside the bobbin 7110 in various manners.
[0323] For example, the lens barrel may be coupled to the bobbin
7110 using an adhesive. In addition, the lens barrel may be coupled
to the bobbin 7110 by screwing. Alternatively, one or more lens
sheets may be integrally formed with the bobbin 7110 without the
lens barrel.
[0324] One lens sheet may be coupled to the lens barrel, or two or
more lenses may constitute an optical system.
[0325] The auto-focusing function is controlled based on the
direction of current. The auto-focusing function may be realized
via movement of the bobbin 7110 in the first direction. For
example, when forward current is applied, the bobbin 7110 may move
upward from the initial position thereof. When reverse current is
applied, the bobbin 7110 may move downward from the initial
position thereof. Alternatively, the distance of movement in a
given direction from the initial position may be increased or
reduced by adjusting the amount of forward or reverse current.
[0326] The bobbin 7110 may be formed on the upper surface and the
lower surface thereof with a plurality of upper support protrusions
and lower support protrusions. Each of the upper support
protrusions may have a cylindrical shape or a prismatic shape, and
may be coupled and fixed to the upper elastic member 7150. Each of
the lower support protrusions may have a cylindrical shape or a
prismatic shape in the same manner as the upper support
protrusions, and may be coupled and fixed to the lower elastic
member 7160.
[0327] Here, the upper elastic member 7150 may be formed with
holes, which correspond to the upper support protrusions, and the
lower elastic member 7160 may be formed with holes, which
correspond to the lower support protrusions. The respective support
protrusions and the respective holes may be fixedly coupled to each
other by thermo-welding or using an adhesive member such as
epoxy.
[0328] The housing 7140 may take the form of a hollow column to
support the first magnet 7130, and may have a substantially square
shape. The first magnet 7130 may be coupled to and disposed on a
side surface portion of the housing 7140. In addition, as described
above, the bobbin 7110 may be disposed to move in the first
direction under the guidance of the elastic members 7150 and 7160
within the housing 7140.
[0329] The upper elastic member 7150 may be provided above the
bobbin 7110, and the lower elastic member 7160 may be provided
below the bobbin 7110. The upper elastic member 7150 and the lower
elastic member 7160 may be coupled to the housing 7140 and the
bobbin 7110. The upper elastic member 7150 and the lower elastic
member 7160 may elastically support upward movement and/or downward
movement of the bobbin 7110 in the first direction. The upper
elastic member 7150 and the lower elastic member 7160 may be leaf
springs.
[0330] The upper elastic member 7150, as illustrated in FIG. 21,
may include a plurality of members separated from each other.
Through the multiply divided structure, the respective divided
parts of the upper elastic member 7150 may receive current having
different polarities, or different voltages. In addition, the lower
elastic member 7160 may have a multiply divided structure, and may
be electrically connected to the upper elastic member 7150.
[0331] Meanwhile, the upper elastic member 7150, the lower elastic
member 7160, the bobbin 7110, and the housing 7140 may be assembled
by, for example, thermo-welding and/or a bonding operation using an
adhesive or the like.
[0332] The base 7210 may be disposed below the bobbin 7110, and may
have a substantially square shape. A printed circuit board 7250 may
be disposed or seated on the base.
[0333] The base 7210 may be formed with a support groove in a
portion thereof that faces the portion of the printed circuit board
7250, on which a terminal surface 7253 is formed, the support
groove having a size that corresponds to that of the terminal
surface. The support groove may be concavely formed to a
predetermined depth from the outer peripheral surface of the base
7210, thereby preventing the portion, on which the terminal surface
7253 is formed, from protruding outwards, or adjusting the extent
to which the portion protrudes.
[0334] A support member 7220 may be disposed on the side surface of
the housing 7140 so as to be spaced apart from the housing 7140,
and may be coupled at the upper side thereof to the upper elastic
member 7150 and coupled at the lower side thereof to the base 7210,
the printed circuit board 7250, or a circuit member 7231. The
support member may support the bobbin 7110 and the housing 7140 so
as to be movable in the second direction and/or the third
direction, which are orthogonal to the first direction, and may be
electrically connected to the first coil 7120.
[0335] Since the support member 7220 according to the embodiment is
disposed on the outer side surface of each corner of the housing
7140, a total of four support members may be provided in a
symmetrical arrangement. In addition, the support member 7220 may
be electrically connected to the upper elastic member 7150. That
is, for example, the support member 7220 may be electrically
connected to a portion of the upper elastic member 7150 in which a
through-hole is formed.
[0336] In addition, since the support member 7220 is formed
separately from the upper elastic member 7150, the support member
7220 and the upper elastic member 7150 may be electrically
connected to each other using a conductive adhesive, a solder, or
the like. Thus, the upper elastic member 7150 may apply current to
the first coil 7120 via the support member 7220, which is
electrically connected thereto.
[0337] The support member 7220 may be connected to the printed
circuit board 7250 through holes formed in the circuit member 7231
and the printed circuit board 7250. Alternatively, no holes may be
formed in the circuit member 7231 and/or the printed circuit board
7250, and the support member 7220 may be electrically soldered to a
corresponding portion of the circuit member 7231.
[0338] Meanwhile, FIG. 21 illustrates the linear support member
7220 according to an embodiment, but the disclosure is not limited
thereto. That is, the support member 7220 may be a plate-shaped
member, for example.
[0339] A second coil 7230 may move the housing 7140 in the second
direction and/or the third direction via electromagnetic
interaction with the first magnet 7130, thereby being capable of
performing hand-tremor compensation.
[0340] Here, the second and third directions may include not only
the x-axis direction (or the first direction) and the y-axis
direction (or the second direction) but also the directions
substantially close to the x-axis and y-axis directions. That is,
the housing 7140 may move in directions parallel to the x-axis and
the y-axis when viewed in terms of driving in the embodiment, but
may move in directions slightly oblique to the x-axis and the
y-axis when moving while being supported by the support member
7220.
[0341] Thus, it may be necessary to provide the first magnet 7130
at a position that corresponds to the second coil 7230.
[0342] The second coil 7230 may be disposed so as to face the first
magnet 7130 fixed to the housing 7140. In an embodiment, the second
coil 7230 may be disposed outside the first magnet 7130.
Alternatively, the second coil 7230 may be downwardly spaced apart
from the first magnet 7130 by a predetermined distance.
[0343] According to the embodiment, a total of four second coils
7230 may be provided respectively on four corner portions of the
circuit member 7231, without being limited thereto. Only two second
coils may be provided respectively in the second direction and in
the third direction, or more than four second coils may be
provided.
[0344] Alternatively, a total of six second coils, which include
one on a first side in the second direction, two on a second side
in the second direction, one on a third side in the third
direction, and two on a fourth side in the third direction, may be
disposed. In this case, the first side and the fourth side may be
next to each other, and the second side and the third side may be
next to each other.
[0345] In the embodiment, the circuit member 7231 may be formed
with a circuit pattern that takes the form of the second coil 7230,
and a separate second coil may be additionally disposed above the
circuit member 7231, without being limited thereto. A circuit
pattern that takes the form of the second coil 7230 may be formed
above the circuit member 7231.
[0346] Alternatively, the second coil 7230 may be configured by
winding a wire in a doughnut shape, or may be formed to have an FP
coil shape, so as to be electrically connected to the printed
circuit board 7250.
[0347] The circuit member 7231 including the second coil 7230 may
be provided or disposed on the upper surface of the printed circuit
board 7250, which is disposed above the base 7210. However, the
disclosure is not limited thereto, and the second coil 7230 may be
disposed in close contact with the base 7210, or may be spaced
apart from the base by a predetermined distance. Alternatively, the
second coil may be formed on a separate board so that the board may
be stacked on and connected to the printed circuit board 7250.
[0348] The printed circuit board 7250 may be electrically connected
to at least one of the upper elastic member 7150 and the lower
elastic member 7160, may be coupled to the upper surface of the
base 7210, and as illustrated in FIG. 21, may be formed with a
through-hole at a position that corresponds to the end of the
support member 7220 so that the support member 7220 is inserted
into the through-hole. Alternatively, the printed circuit board may
be electrically connected to and/or bonded to the support member
without a through-hole.
[0349] A terminal 7251 may be disposed or formed on the printed
circuit board 7250. In addition, the terminal 7251 may be disposed
on the bent terminal surface 7253. A plurality of terminals 7251
may be disposed on the terminal surface 7253, and may supply
current to the first coil 7120 and/or the second coil 7230 upon
receiving an external voltage. The number of terminals formed on
the terminal surface 7253 may be increased or reduced based on the
constituent elements that need to be controlled. In addition, the
printed circuit board 7250 may include one terminal surface 7253,
or three or more terminal surfaces.
[0350] The cover member 7300 may have a substantially box shape,
may accommodate, for example, the movable unit described above, the
second coil 7230, and a portion of the printed circuit board 7250
therein, and may be coupled to the base 7210. The cover member 7300
may protect, for example, the movable unit, the second coil 7230,
and the printed circuit board 7250, which are accommodated therein,
and more particularly, may limit outward leakage of an
electromagnetic field, which is created by, for example, the first
magnet 7130, the first coil 7120, the second coil 7230 therein,
thereby enabling the electromagnetic field to be focused.
[0351] FIG. 22 is a perspective view illustrating the base 7210,
the filter holder 7400, and the sensor holder 7500 according to an
embodiment. FIG. 23 is an exploded perspective view illustrating
the base 7210, the filter holder 7400, and the sensor holder 7500
according to the embodiment.
[0352] The filter 7410 may be mounted in the filter holder 7400.
The filter 7410 may be mounted in the filter holder 7400 at a
position at which it faces the lens barrel and an image sensor 7510
in the first direction. The filter 7410 may filter light within a
specific wavelength range of incident light directed through the
lens barrel, and the light, which has passed through the filter
7410, may be incident on the image sensor 7510.
[0353] Here, the filter 7410 may be, for example, an infrared
filter that prevents infrared light from being incident on the
image sensor 7510. The image sensor 7510 may be mounted on the
upper surface of the sensor holder 7500, and the light, which has
passed through the filter 7410, may be incident on the image sensor
so that an image is formed thereon.
[0354] The sensor holder 7500 may be formed of a flexible material
or a hard material. However, in order to allow the connection board
7600, which is electrically connected to the sensor holder 7500, to
be easily connected to external devices and the camera module, the
sensor holder may be formed of a flexible material that is easily
changed in position.
[0355] The base 7210 and the filter holder 7400 may be, for
example, adhered to each other using an adhesive such as epoxy.
However, the adhered portion in which the base 7210 and the filter
holder 7400 are coupled to each other may be vulnerable to shear
force applied from the outside.
[0356] That is, when external force is applied to the base 7210 and
the filter holder 7400 in different directions in the x-y plane,
shear force may be applied to the adhered portion, and when this
shear force is repeatedly and continuously applied, the adhered
portion may be damaged.
[0357] When the adhered portion is damaged by the shear force, the
lens barrel and the image sensor 7510 may be moved from designed
positions thereof in the x-y plane. Thereby, the focus alignment of
the lens barrel and the image sensor 7510 may be broken, causing
remarkable deterioration in the quality of an image captured by the
camera module.
[0358] In addition, when the shear force is repeatedly and
continuously applied to the adhered portion, the coupling of the
base 7210 and the filter holder 7400 may be broken. Thereby, the
lens driving device 7100 including the base 7210 may be separated
from the filter holder 7400, which may cause malfunction of the
camera module.
[0359] Accordingly, in the camera module of the embodiment, the
adhered portion of the base 7210 and the filter holder 7400 may
have a structure capable of withstanding strong shear force.
[0360] In the camera module of the embodiment, the adhered portion
may have the following structure so as to withstand strong shear
force without breakage.
[0361] As illustrated in FIG. 23, the adhered portion of the base
7210 and the filter holder 7400 may be formed with an uneven
structure. That is, the base 7210 may be formed with a protruding
portion and an indented portion, and the filter holder 7400 may
have a shape that corresponds to the base 7210.
[0362] For example, the base 7210 may be formed with a protruding
portion 71000, and the filter holder 7400 may have a shape that
corresponds to the base 7210, i.e. may be formed with an indented
portion 72000. Here, the protruding portion 71000 may be formed on
the bottom of the base 7210, and the indented portion 72000 may be
formed in the top of the filter holder 7400.
[0363] FIG. 24 is a bottom view illustrating the base 7210
according to an embodiment. FIG. 25 is a plan view illustrating the
filter holder 7400 according to an embodiment. As illustrated in
FIGS. 23 to 25, the protruding portion 71000 may take the form of a
pair of bars, which are provided on respective sides of the base
7210 and are symmetrical to each other about the center of the base
7210.
[0364] Here, the indented portion (7 bosses (71100)0) may be
provided in the filter holder 7400 in a shape, position, and number
that correspond to those of the protruding portion 71000. Thus, in
order to correspond to the protruding portion 71000 illustrated in
FIG. 24, the indented portion 72000, as illustrated in FIG. 25, may
include a pair of indented portions, which are provided on
respective sides of the filter holder 7400 and are symmetrical to
each other about the center of the filter holder 7400.
[0365] Each of the protruding portion 71000 and the indented
portion 72000 is illustrated as being provided in a pair in FIGS.
23 and 24, without being limited thereto. For example, a pair of
protruding portions 71000 and a pair of indented portions 72000 may
be arranged in the vertical direction as illustrated in FIGS. 23
and 24, or may be provided in the horizontal direction on the base
7210 and the filter holder 7400.
[0366] In addition, based on the drawing, a total of two pairs may
be provided respectively in the vertical direction and the
horizontal direction. In addition, the protruding portion 71000 and
the indented portion 72000 may not be continuous and singular, but
may include a plurality of smaller ones spaced apart from each
other.
[0367] However, regardless of the shape thereof, the protruding
portion 71000 and the indented portion 72000 may have the same
shape and the same number at corresponding positions.
[0368] An adhesive material PP may be applied to the adhered
portion including the protruding portion 71000 and the indented
portion 72000. Through the curing of the adhesive material PP, the
base 7210 formed with the protruding portion 71000 and the filter
holder 7400 formed with the indented portion 72000 may be coupled
to each other.
[0369] With the structure described above, in the camera module in
which the base 7210 and the filter holder 7400 are coupled to each
other, even when external force is applied in different directions
in the x-y plane to the base 7210 and the filter holder 7400 so
that shear force is applied to the adhered portion, movement of the
protruding portion 71000 in the x-y plane may be limited by the
indented portion.
[0370] Accordingly, excessive movement of the base 7210 relative to
the filter holder 7400 in the x-y plane may be limited by the
protruding portion 71000 and the indented portion, and therefore,
it is possible to prevent damage to or breakage of the adhered
portion by shear force.
[0371] In this way, it is possible to prevent deterioration in the
quality of an image captured by the camera module caused by
excessive movement of the base 7210 relative to the filter holder
7400, and to prevent erroneous operation and operation stoppage of
the camera module due to damage to or breakage of the adhered
portion.
[0372] FIG. 26 is a side cross-sectional view illustrating the
state in which the base 7210 and the filter holder 7400 are coupled
to each other according to an embodiment. FIG. 27 is an enlarged
view illustrating portion "AA" of FIG. 26.
[0373] As illustrated in FIGS. 26 and 27, the adhesive material PP
may be applied to the adhered portion of the base 7210 and the
filter holder 7400 including the protruding portion 71000 and the
indented portion 72000 so that the base 7210 and the filter holder
7400 are coupled to each other by adhesion.
[0374] Here, in the adhered portion, a first distance DD1, which is
defined as the distance between the lower surface of the protruding
portion 71000 and the bottom surface of the indented portion 72000,
may range, for example, from 20 .mu.m to 150 .mu.m, more
appropriately from 30 .mu.m to 120 .mu.m, and still more
appropriately from 50 .mu.m to 100 .mu.m.
[0375] In addition, a second distance DD2, which is defined as the
distance between an adhered portion of the base 7210 excluding the
protruding portion 71000 and an adhered portion of the filter
holder 7400 excluding the indented portion 72000, may range, for
example, from 20 .mu.m to 150 .mu.m, more appropriately from 30
.mu.m to 120 .mu.m, and still more appropriately from 50 .mu.m to
100 .mu.m.
[0376] The reason why the first distance DD1 and the second
distance DD2 are provided is to perform an active alignment process
of coupling the lens driving device 7100 and the filter holder 7400
to each other.
[0377] That is, after the lens driving device 7100 is separately
assembled, and then the filter holder 7400 and the sensor holder
7500 are separately assembled, the lens driving device 7100 is
coupled to the filter holder 7400. When the lens driving device
7100 is coupled to the filter holder 7400, it is necessary to
adjust a focal length in the first direction between a lens
provided in the lens driving device 7100 and the image sensor 7510
mounted on the sensor holder 7500. This may be performed through
the active alignment process.
[0378] When performing the active alignment process, the focal
length is adjusted to suit to a designed value while moving the
lens driving device 7100 including the base 7210 in the first
direction relative to the coupled assembly of the filter holder
7400 and the sensor holder 7500.
[0379] In order to adjust the focal length as described above, an
engineering margin may be required between the base 7210 and the
filter holder 7400. The first distance DD1 and the second distance
DD2 may serve as the engineering margin.
[0380] Meanwhile, since the engineering margin for the adjustment
of the focal length may be consistent in the first direction, the
first distance DD1 and the second distance DD2 may be equally
set.
[0381] When the focal length is completely adjusted via the active
alignment process, the base 7210 and the filter holder 7400 may be
adhered to each other. Thus, after completion of the active
alignment process, a space defined by the first distance DD1 and
the second distance DD2 is filled with the adhesive material PP,
and when the adhesive material PP is cured, the lens driving device
7100 including the base 7210 and the coupled assembly of the filter
holder 7400 and the sensor holder 7500 may be coupled to each
other. Here, the adhesive material PP may be, for example,
epoxy.
[0382] Meanwhile, although not illustrated, instead of being
applied to a portion close to the protruding portion 71000 and the
indented portion 72000, the adhesive material PP may be applied to
other portions close to the base 7210 and the filter holder 7400,
for example, to the side surface of the base 7210, the side
surfaces of the filter holder 7400 and the sensor holder 7500, and
the upper surface of the sensor holder 7500.
[0383] This serves to realize firmer coupling between the lens
driving device 7100 and the coupled assembly of the filter holder
7400 and the sensor holder 7500.
[0384] Meanwhile, as illustrated in FIG. 27, a second width WW2,
which is defined as the width of the indented portion 72000, may be
larger than a first width WW1, which is defined as the width of the
protruding portion 71000. Here, the difference between the second
width WW2 and the first width WW1 may range, for example, from 80
.mu.m to 170 .mu.m, and more appropriately from 100 .mu.m to 150
.mu.m.
[0385] This structure serves to allow the lens driving device to be
disposed at a designed position in the x-y plane relative to the
coupled assembly of the filter holder 7400 and the sensor holder
7500 during the active alignment process.
[0386] That is, in order to dispose the lens driving device at a
designed position in the x-y plane relative to the coupled assembly
of the filter holder 7400 and the sensor holder 7500, during the
active alignment process, it may be necessary to move the lens
driving device 7100 in the x-y plane. To this end, the engineering
margin may be required between the protruding portion 71000 and the
indented portion 72000. A width, which is measured as the
difference between the second width WW2 and the first width WW1,
may serve as the engineering margin.
[0387] Similar to the above description, the space defined by the
width, which is measured as the difference between the second width
WW2 and the first width WW1, is filled with the adhesive material
PP, and when the adhesive material is cured, the lens driving
device 7100 may be coupled to the coupled assembly of the filter
holder 7400 and the sensor holder 7500.
[0388] FIG. 28 is a bottom view illustrating the base 7210
according to another embodiment. FIG. 29 is a plan view
illustrating the filter holder 7400 according to the
embodiment.
[0389] As illustrated in FIG. 28, the protruding portion 71000 may
include a plurality of bosses 71100. For example, the bosses 71100
may be provided on the lower surface of the base 7210, and the
number and position thereof may be appropriately selected based on
the size and shape of the base 7210 and the filter holder 7400.
[0390] Although FIG. 28 illustrates the bosses 71100 as having a
circular cross-sectional shape, in another embodiment, each of the
bosses may have a semi-circular, curvilinear, or polygonal
cross-sectional shape.
[0391] The indented portion 72000 may be provided in the filter
holder 7400 in a shape, position, and number that correspond to
those of the bosses 71100. Here, the cross-sectional area of the
indented portion 72000 may be larger than the cross-sectional area
of the bosses 71100.
[0392] As described above, this serves to secure the engineering
margin that is required in order to dispose the lens driving device
7100 at a designed position in the x-y plane relative to the
coupled assembly of the filter holder 7400 and the sensor holder
7500 during the active alignment process of coupling the lens
driving device 7100 to the coupled assembly of the filter holder
7400 and the sensor holder 7500.
[0393] In addition, as described above, during the active alignment
process, the length of the boss 71100 in the first direction may be
appropriately smaller than the depth of the indented portion 72000
in the first direction in order to adjust the focal length in the
first direction.
[0394] Meanwhile, although not illustrated, in another embodiment,
the protruding portion 71000 may be formed on the top of the filter
holder 7400, and the indented portion 72000 may be formed in the
bottom of the base 7210.
[0395] This is the same as or extremely similar to the structure
described with reference to FIGS. 22 to 29 except that the element
formed with the protruding portion 71000 and the element formed
with the indented portion 72000 are reversed. Thus, a repeated
description of the concrete structure will be omitted.
[0396] FIG. 30 is a bottom view illustrating the filter holder 7400
according to still another embodiment. FIG. 31 is a plan view
illustrating the sensor holder 7500 according to the
embodiment.
[0397] In the embodiment, the adhered portion of the filter holder
7400 and the sensor holder 7500 may be configured such that the
protruding portion or the indented portion is formed in the filter
holder 7400 and the sensor holder 7500 may have a shape that
corresponds to that of the filter holder 7400.
[0398] In the embodiment, as illustrated in FIGS. 30 and 31, the
protruding portion 71000 is formed on the lower surface of the
filter holder 7400, and the indented portion 72000 may be formed in
the upper surface of the sensor holder 7500 in a position, shape,
and number that correspond to those of the protruding portion
71000.
[0399] When the protruding portion 71000 and the indented portion
72000 corresponding thereto are formed on the adhered portion of
the filter holder 7400 and the sensor holder 7500, it is possible
to prevent damage to or breakage of the adhered portion even when
strong shear force is applied to the adhered portion of the filter
holder 7400 and the sensor holder 7500.
[0400] Accordingly, it is possible to prevent, for example,
deterioration in the quality of an image, erroneous operation, and
operation stoppage of the camera module due to breakage of the
adhered portion of the filter holder 7400 and the sensor holder
7500.
[0401] Meanwhile, similar to the description made with reference to
FIGS. 22 to 29, the protruding portion 71000 may include the
plurality of bosses 71100 each having a circular, semi-circular,
curvilinear, or polygonal cross-sectional shape, and the indented
portion 72000 may be provided in a shape, position, and number that
correspond to those of the bosses 71100.
[0402] In addition, the bosses 71100 may be formed on the sensor
holder 7500, and the indented portion 72000 may be formed in the
filter holder 7400 in a shape, position, and number that correspond
to those of the bosses 71100.
[0403] Meanwhile, in the case in which the protruding portion 71000
or the indented portion 72000 is formed in the sensor holder 7500,
the sensor holder 7500 may be formed of a hard material since the
protruding portion 71000 or the indented portion 72000 needs to
resist deformation.
[0404] Here, the hard sensor holder 7500 may be formed of
high-temperature co-fired ceramic (HTCC), for example.
[0405] Here, the entire sensor holder 7500 may not be formed of a
hard material, but at least the adhered portion needs to be formed
of a hard material. Thus, at least the adhered portion of the
sensor holder 7500 may be formed of high-temperature co-fired
ceramic, for example.
[0406] FIG. 32 is an exploded perspective view illustrating a
camera module according to still another embodiment. FIG. 33 is an
exploded perspective view illustrating a lens driving device of
FIG. 32.
[0407] Referring to FIG. 32, the camera module 1 may be any one of
a mobile phone, a smartphone, a portable smart device, a digital
camera, a laptop computer, a digital broadcasting terminal, a
Personal Digital Assistant (PDA), a Portable Multimedia Player
(PMP), and a navigation tablet PC, but not limited hereto. Any kind
of device for capturing a picture or motion picture may be
possible.
[0408] Referring to FIG. 32, the camera module 1 may include a lens
driving device 10, a lens module (not illustrated), an infrared
cutoff filter 30, a printed circuit board 40, an image sensor 50, a
holder member 60, and a controller (not illustrated).
[0409] Hereinafter, the lens driving device will be described with
reference to FIG. 33.
[0410] Referring to FIG. 33, the lens driving device 10 according
to the embodiment may include a cover member 100, a mover 350
including a first mover 200 and a second mover 300, a stator 400, a
base 500, a support member 600, and a sensing unit 700.
[0411] However, in the lens driving device 10 according to the
embodiment, one or more of the cover member 100, the first mover
200, the second mover 300, the stator 400, the base 500, the
support member 600, and the sensing unit 700 may be omitted.
[0412] The cover member 100 may define the external appearance of
the lens driving device 10. The cover member 100 may take the form
of a hexahedron, the lower portion of which is open, but not
limited thereto.
[0413] The cover member 100 may include an upper surface 101 and a
side surface 102 extending downwards from the outer rim of the
upper surface 101.
[0414] Meanwhile, the cover member 100 may be mounted on the top of
the base 500.
[0415] The first mover 200, the second mover 300, the stator 400,
and the support member 600 may be located in the inner space
defined by the cover member 100 and the base 500.
[0416] In addition, the cover member 100 may be mounted on the base
500 such that the inner side surface thereof is in close contact
with a part or the entirety of a side surface portion of the base
500, which will be described below. Through this structure, the
cover member 100 may function to protect inner constituent elements
from external shocks and to prevent the introduction of outside
contaminants.
[0417] In an embodiment, the cover member 100 may be formed of a
metal. More specifically, the cover member 100 may be formed of a
metal board. In this case, the cover member 100 may prevent radio
frequency interference.
[0418] That is, the cover member 100 may prevent radio waves
generated outside the lens driving device 10 from being introduced
into the cover member 100. In addition, the cover member 100 may
prevent radio waves generated inside the cover member 100 from
being discharged to the outside of the cover member 100. However,
the material of the cover member 100 is not limited thereto.
[0419] The cover member 100 may include an opening 110, which is
formed in the upper surface 101 to expose the lens module. The
opening 110 may have a shape that corresponds to that of the lens
module.
[0420] That is, light introduced through the opening 110 may pass
through the lens module. Meanwhile, the light, which has passed
through the lens module, may be transmitted to the image
sensor.
[0421] The first mover 200, which constitutes the mover 350, may
include a bobbin 210 and a first drive unit 220.
[0422] The first mover 200 may be coupled to the lens module, which
is a constituent element of the camera module 1 illustrated in FIG.
32. However, the lens module may also be described as a constituent
element of the lens driving device 10.
[0423] That is, the lens module may be located inside the first
mover 200. In other words, the outer peripheral surface of the lens
module may be coupled to the inner peripheral surface of the first
mover 200.
[0424] Meanwhile, the first mover 200 may be integrally moved with
the lens module via interaction with the second mover 300, which
also constitutes the mover 350. That is, the first mover 200 may
move the lens module.
[0425] The first mover 200 may include the bobbin 210. In addition,
the first mover 200 may include the first drive unit 220 coupled to
the bobbin 210.
[0426] The bobbin 210 may be coupled to the lens module. More
specifically, the outer peripheral surface of the lens module may
be coupled to the inner peripheral surface of the bobbin 210.
Meanwhile, the first drive unit 220 may be coupled to the bobbin
210. In addition, the lower portion of the bobbin 210 may be
coupled to a lower support member 620 and the upper portion of the
bobbin 210 may be coupled to an upper support member 610. The
bobbin 210 may be located inside a housing 310. The bobbin 210 may
move relative to the housing 310.
[0427] The bobbin 210 may include a lens coupling portion 211
formed therein. The lens module may be coupled to the lens coupling
portion 211. A screw-thread may be formed in the inner peripheral
surface of the lens coupling portion 211 so as to correspond to a
screw-thread formed in the outer peripheral surface of the lens
module. That is, the outer peripheral surface of the lens module
may be screwed to the inner peripheral surface of the lens coupling
portion 211.
[0428] The bobbin 210 may include a sensor guide portion (not
illustrated) to which an auto-focusing feedback sensor (not
illustrated) is coupled. The auto-focusing feedback sensor coupled
to the sensor guide portion may sense a second drive unit 320,
which is mounted on the housing 310 and is integrally moved with
the bobbin 210, thereby sensing movement of the bobbin 210. In one
example, the auto-focusing feedback sensor may be a hall sensor,
and the second drive unit 320 may be a magnet.
[0429] The bobbin 210 may include a first drive unit coupling
portion 212, around which the first drive unit 220 is wound or
mounted. The first drive unit coupling portion 212 may be
integrally formed on the outer side surface of the bobbin 210. In
addition, the first drive unit coupling portion 212 may be
continuously formed, or may be embodied as multiple parts spaced
apart from each other by a predetermined distance along the outer
side surface of the bobbin 210. The first drive unit coupling
portion 212 may include a recess formed in a portion of the outer
side surface of the bobbin 210. The first drive unit 220 may be
located on the first drive unit coupling portion 212. The first
drive unit 220 located on the first drive unit coupling portion 212
may be supported by a support portion protruding outward from the
lower side of the recess.
[0430] The bobbin 210 may include an upper coupling portion 213
coupled to the upper support member 610. The upper coupling portion
213 may be coupled to an inner side portion 612 of the upper
support member 610. In one example, the upper coupling portion 213,
which takes the form of a protrusion, may be inserted into and
coupled to a recess or a hole in the inner side portion 612. Unlike
this, the upper support member 610 may include a protrusion and the
bobbin 210 may include a recess so that the two are coupled to each
other. The bobbin 210 may further include a lower coupling portion
(not illustrated) coupled to the lower support member 620. The
lower coupling portion formed on the lower portion of the bobbin
210 may be coupled to an inner side portion 622 of the lower
support member 620. In one example, the lower coupling portion,
which takes the form of a protrusion, may be inserted into and
coupled to a recess or a hole in the inner side portion 622.
[0431] The first drive unit 220 may be located so as to face the
second drive unit 320 of the second mover 300. The first drive unit
220 may move the bobbin 210 relative to the housing 310 via
electromagnetic interaction with the second drive unit 320. The
first drive unit 220 may include a coil. The coil may be guided by
the first drive unit coupling portion 212 and wound around the
outer side surface of the bobbin 210. In another embodiment, four
coils may be independently disposed on the outer side surface of
the bobbin 210 such that two neighboring coils have an angle of 90
degrees therebetween. In the case in which the first drive unit 220
includes the coils, a voltage may be supplied to the coils through
the upper support member 610. Here, the upper support member 610
may be divided into a pair of members in order to supply a voltage
to the respective coils. Meanwhile, the first drive unit 220 may
include a pair of lead wires (not illustrated) for the supply of a
voltage. In this case, the respective lead wires of the first drive
unit 220 may be electrically coupled to a pair of upper support
members 610a and 610b. When a voltage is supplied to the coils, an
electromagnetic field may be created around the coils. In another
embodiment, the first drive unit 220 may include a magnet. In this
case, the second drive unit 320 may include a coil.
[0432] The second mover 300 may be located outside the first mover
200 so as to face the first mover 200. The second mover 300 may be
supported by the base 500 located thereunder. The second mover 300
may be located in the inner space of the cover member 100.
[0433] The second mover 300 may include the housing 310 located
outside the bobbin 210. In addition, the second mover 300 may
include the second drive unit 320, which is located so as to face
the first drive unit 220 and is fixed to the housing 310.
[0434] The housing 310 may be formed to have a shape that
corresponds to the inner side surface of the cover member 100,
which defines the external appearance of the lens driving device
10. In addition, the housing 310 may be formed of an insulating
material and may be an injection-molded article in consideration of
productivity. The housing 310 may be movable for optical image
stabilization (OIS) and may be spaced apart from the cover member
100 by a constant distance. However, in an AF model, the housing
310 may be fixed on the base 500. In addition, in the AF model, the
housing 310 may be omitted, and a magnet, which serves as the
second drive unit 320, may be fixed to the cover member 100.
[0435] The housing 310 may be open at the upper side and the lower
side thereof so that the first mover 200 is accommodated therein so
as to be movable in the vertical direction. The housing 310 may
include an inner space 311 therein, which is open at the upper and
lower sides thereof. The first mover 200 may be movably located in
the inner space 311. That is, the inner space 311 may have a shape
that corresponds to that of the first mover 200. In addition, the
inner peripheral surface of the inner space 311 may be spaced apart
from the outer peripheral surface of the first mover 200.
[0436] The housing 310 may include a second drive unit coupling
portion 312 formed on the side surface thereof. The second drive
unit coupling portion is formed to have a shape that corresponds to
that of the second drive unit 320 and accommodates the second drive
unit 320 therein. That is, the second drive unit coupling portion
312 may accommodate and fix the second drive unit 320. The second
drive unit 320 may be fixed to the second drive unit coupling
portion 312 using an adhesive (not illustrated). Meanwhile, the
second drive unit coupling portion 312 may be located on the inner
peripheral surface of the housing 310. This is advantageous for
electromagnetic interaction between the second drive unit 320 and
the first drive unit 220 located therein. In one example, the
second drive unit coupling portion 312 may be open at the lower
side thereof. This is advantageous for electromagnetic interaction
between the second drive unit 320 and a third drive unit 420
located thereunder. In one example, four second drive unit coupling
portions 312 may be provided. Each of the four second drive unit
coupling portions 312 may be coupled to the second drive unit 320.
Meanwhile, the four second drive unit coupling portions 312 may be
disposed on the respective corner portions of the housing 310.
[0437] The upper support member 610 may be coupled to the upper
portion of the housing 310, and the lower support member 620 may be
coupled to the lower portion of the housing 310. The housing 310
may include an upper coupling portion 313 coupled to the upper
support member 610. The upper coupling portion 313 may be coupled
to an outer side portion 611 of the upper support member 610. In
one example, the upper coupling portion 313, which takes the form
of a protrusion, may be inserted into and coupled to a recess or a
hole in the outer side portion 611. In another embodiment, the
upper support member 610 may include a protrusion and the housing
310 may include a recess so that the two are coupled to each other.
The housing 310 may further include a lower coupling portion (not
illustrated) coupled to the lower support member 620. The lower
coupling portion formed on the lower portion of the housing 310 may
be coupled to an outer side portion 621 of the lower support member
620. In one example, the lower coupling portion, which takes the
form of a protrusion, may be inserted into and coupled to a recess
or a hole in the outer side portion 621.
[0438] The second drive unit 320 may be located so as to face the
first drive unit 220 of the first mover 200. The second drive unit
320 may move the first drive unit 220 via electromagnetic
interaction with the first drive unit 220. The second drive unit
320 may include a magnet. The magnet may be fixed to the second
drive unit coupling portion 312 of the housing 310. In one example,
the second drive unit 320, as illustrated in FIG. 33, may include
four magnets, which are independently disposed such that two
neighboring coils have an angle of 90 degrees therebetween.
[0439] That is, the second drive unit 320 may be equidistantly
mounted on four side surfaces of the housing 310 to realize the
efficient use of the inner volume. In addition, the second drive
unit 320 may be disposed on four corner portions of the housing
310. Meanwhile, the second drive unit 320 may be adhered to the
housing 310 using, for example, an adhesive, without being limited
thereto. In another embodiment, the first drive unit 220 may
include a magnet, and the second drive unit 320 may include a
coil.
[0440] The stator 400 may be fixed to the base 500. The stator 400
may be located so as to face the lower side of the second mover
300. Meanwhile, the stator 400 may move the second mover 300. In
addition, the stator 400 may have through-holes 411 and 421 formed
in the center thereof so as to correspond to the lens module.
[0441] The stator 400 may include a circuit board 410 located
between the third drive unit 420 and the base 500. In addition, the
stator 400 may include the third drive unit 420 located under the
second drive unit 320 so as to face the same.
[0442] The circuit board 410 may include a flexible printed circuit
board. The circuit board 410 may be located between the third drive
unit 420 and the base 500. Meanwhile, the circuit board 410 may
supply a voltage to the third drive unit 420.
[0443] In addition, the circuit board 410 may supply a voltage to
the first drive unit 220 through a lateral support member 630 and
the upper support member 610.
[0444] The circuit board 410 may have therein the through-hole 411,
through which light that has passed through the lens module
passes.
[0445] In addition, a portion of the circuit board 410 may be bent
from the side surface of the base 500 so as to protrude from the
lower surface of the base 500. A terminal unit 412 may be formed on
the bent portion of the circuit board 410 that protrudes from the
lower surface of the base 500.
[0446] The terminal unit 412 may be electrically connected to the
printed circuit board 40, which is illustrated in FIG. 32 and will
be described below, and a voltage or a control signal may be
applied to the circuit board 410 through the terminal unit 412.
[0447] The third drive unit 420 may include a coil. When a voltage
is applied to the coil of the third drive unit 420, the second
drive unit 320 and the housing 310 fixed to the second drive unit
320 may be integrally moved via interaction between the third drive
unit and the second drive unit 320. The third drive unit 420 may be
mounted on or electrically connected to the circuit board 410.
[0448] Meanwhile, the third drive unit 420 may have therein the
through-hole 421, through which light from the lens module passes.
In addition, in consideration of reduction of the size of the lens
driving device 10 (a reduction in height in the z-axis direction,
i.e. the optical-axis direction), the third drive unit 420 may be
formed as an FP coil, which is a patterned coil, and may be
disposed or mounted on the circuit board 410.
[0449] The base 500 may support the second mover 300. The printed
circuit board 40 illustrated in FIG. 32 may be located below the
base 500.
[0450] The base 500 may have a through-hole 510 formed at a
position that corresponds to the lens coupling portion 211. The
base 500 may perform a sensor holder function to protect the image
sensor 50 illustrated in FIG. 32.
[0451] In an embodiment, the base 500 may include a foreign
substance collection unit (not illustrated), which collects a
foreign substance introduced into the cover member 100. The foreign
substance collection unit may be located on the upper surface of
the base 500 and may include an adhesive material to collect a
foreign substance in the inner space defined by the cover member
100 and the base 500. The base 500 may include a sensor mounting
portion 530 to which the sensor unit 700 is coupled.
[0452] That is, the sensor unit 700 may be mounted on the sensor
mounting portion 530. Here, the sensor unit 700 may sense
horizontal movement of the housing 310 by sensing the second drive
unit 320 coupled to the housing 310. In one example, two sensor
mounting portions 530 may be provided. The sensor unit 700 may be
located on each of the two sensor mounting portions 530. In this
case, the sensor unit 700 may be disposed so as to sense movement
of the housing 310 in the x-axis and y-axis directions.
[0453] The support member 600 may interconnect two or more of the
first mover 200, the second mover 300, and the base 500. The
support member 600 may elastically interconnect two or more of the
first mover 200, the second mover 300, and the base 500 to enable
relative movement between the respective constituent elements. That
is, the support member 600 may be an elastic member. In an
embodiment, as illustrated in FIG. 33, the support member 600 may
include the upper support member 610, the lower support member 620,
and the lateral support member 630. Meanwhile, an electrical
conduction member (not illustrated) may be provided separately from
the support member 600 to electrically interconnect two or more of
the upper support member 610, the lower support member 620, and the
lateral support member 630.
[0454] In one example, the upper support member 610 may include the
outer side portion 611, the inner side portion 612, and a
connecting portion 613. The upper support member 610 may include
the outer side portion 611 coupled to the housing 310, the inner
side portion 612 coupled to the bobbin 210, and the connecting
portion 613 configured to elastically interconnect the outer side
portion 611 and the inner side portion 612.
[0455] The upper support member 610 may be connected to the upper
portion of the first mover 200 and the upper portion of the second
mover 300. More specifically, the upper support member 610 may be
coupled to the upper portion of the bobbin 210 and the upper
portion of the housing 310. The inner side portion 612 of the upper
support member 610 may be coupled to the upper coupling portion 213
of the bobbin 210, and the outer side portion 611 of the upper
support member 610 may be coupled to the upper coupling portion 313
of the housing 310.
[0456] In an embodiment, the upper support member 610 may be
divided into a pair of members. That is, the upper support member
610 may include a first upper support member 610a and a second
upper support member 610b. Here, each of the first upper support
member 610a and the second upper support member 610b may be a coil,
and may be connected to a corresponding one of the lead wires of
the first drive unit 220 to supply a voltage. In other words, the
pair of upper support members 610a and 610b may be used to apply a
voltage to the first drive unit 220. In one example, the upper
support member 610 may receive a voltage from the circuit board 410
through the lateral support member 630. That is, the first drive
unit 220 may receive a voltage from the circuit board 410 through
the lateral support member 630 and the upper support member
610.
[0457] In one example, the lower support member 620 may include the
outer side portion 621, the inner side portion 622, and a
connecting portion 623. The lower support member 620 may include
the outer side portion 621 coupled to the housing 310, the inner
side portion 622 coupled to the bobbin 210, and the connecting
portion 623 configured to elastically interconnect the outer side
portion 621 and the inner side portion 622.
[0458] The lower support member 620 may be connected to the lower
portion of the first mover 200 and the lower portion of the second
mover 300. More specifically, the lower support member 620 may be
coupled to the lower portion of the bobbin 210 and the lower
portion of the housing 310. The inner side portion 622 of the lower
support member 620 may be coupled to the lower coupling portion of
the bobbin 210, and the outer side portion 621 of the lower support
member 620 may be coupled to the lower coupling portion of the
housing 310.
[0459] The lateral support member 630 may have one end fixed to the
stator 400 or the base 500 and the other end coupled to the upper
support member 610 or the second mover 300. In one example, the
lateral support member 630 may be coupled at one side thereof to
the base 500 and at the other side thereof to the housing 310. In
another embodiment, the lateral support member 630 may be coupled
at one side thereof to the stator 400 and at the other side thereof
to the upper support member 610. The lateral support member 630 may
elastically support the second mover 300 relative to the base 500
so as to allow the second mover 300 to horizontally move or
tilt.
[0460] In one example, the lateral support member 630 may include a
leaf spring. In one example, the lateral support member 630 may
include leaf springs located respectively on four outer side
surfaces of the housing 310. In an embodiment, the lateral support
member 630 may include a plurality of wires. Here, the number of
wires may be six or eight.
[0461] In one example, the lateral support member 630 may include a
constituent element, which is coupled to the upper support member
610 in order to absorb shocks. The shock-absorbing element may be
provided on one of the lateral support member 630 and the upper
support member 610. The shock-absorbing element may be a separate
member such as a damper (not illustrated). In addition, the
shock-absorbing element may be realized by changing the shape of a
portion of one of the lateral support member 630 and the upper
support member 610.
[0462] The sensor unit 700 may be used for any one of auto-focusing
(AF) feedback and optical image stabilization (OIS) feedback. That
is, the sensor unit 700 may sense the position or movement of one
or more of the first mover 200 and the second mover 300. In one
example, the sensor unit 700 may sense horizontal movement or
tilting of the second mover 300 to provide information for OIS
feedback.
[0463] The sensor unit 700 may be disposed on the stator 400. The
sensor unit 700 may be located on the upper surface or the lower
surface of the circuit board 410 of the stator 400. In an
embodiment, the sensor unit 700 may be disposed on the lower
surface of the circuit board and may be located on the sensor
mounting portion 530 of the base 500. In an embodiment, the sensor
unit 700 may include a hall sensor. Here, the sensor unit 700 may
sense movement of the second mover 300 relative to the stator 400
by sensing the magnetic field of the second drive unit 320. In one
example, more than two sensor units 700 may be provided to sense
movement of the second mover 300 in both the x-axis direction and
the y-axis direction.
[0464] FIG. 34 is a longitudinal cross-sectional view of the
remainder of the camera module excluding the lens driving device of
FIG. 32.
[0465] Referring to FIGS. 33 and 34, the circuit board 410, which
include the flexible printed circuit board described above with
reference to FIG. 33, includes a first circuit board portion 413
and a second circuit board portion 414.
[0466] The first circuit board portion 413 is defined as a portion
that is disposed so as to face the upper surface of the base 500,
and the second circuit board portion 414 is defined as a portion
that is bent downward toward the side surface of the base 500 so as
to protrude or extend toward the lower surface of the base 500.
[0467] The second circuit board portion 414 protrudes or extends by
the first distance D1 when measured from the lower surface of the
base 500. The terminal unit 412 may be formed on the second circuit
board portion 414.
[0468] In the embodiment, in the case in which the first circuit
board 410 includes a flexible printed circuit board, for example,
the position and bending angle of the second circuit board portion
414 relative to the base 500 may not be consistent.
[0469] That is, for example, the position and bending angle of the
second circuit board portion 414, which is bent along the side
surface of the base 500, may differ for each camera module.
[0470] In the case in which the position and bending angle of the
second circuit board portion 414, which is bent along the side
surface of the base 500, differs for each camera module, it is very
difficult to accurately interconnect a terminal formed on the
second circuit board portion 414 and a terminal formed on the
printed circuit board 40, which will be described below, and
consequently, to assemble the terminal formed on the circuit board
410 and the terminal formed on the printed circuit board 40 with
each other through an automated process.
[0471] In the embodiment, in order to make the position and bending
angle of the second circuit board portion 414, which is bent along
the side surface of the base 500, be consistent for each camera
module 1, the base 500 is formed with a support portion 540 to
support the second circuit board portion 414.
[0472] The support portion 540 may protrude from the lower surface
of the base 500. For example, the support portion 540 may have a
plate shape.
[0473] The support portion 540, which has a plate shape and
protrudes from the lower surface of the base 500, may be formed to
have a shape that corresponds to the second circuit board portion
414.
[0474] In addition, the support portion 540 may be formed in a
direction parallel to the second circuit board portion 414 in order
to be able to be in surface contact with the second circuit board
portion 414.
[0475] In the embodiment, the protruding length of the support
portion 540, measured from the lower surface of the base 500, is
smaller than the length of the second circuit board portion 414.
This serves to prevent erroneous electrical connection between the
second circuit board portion 414 and the printed circuit board 40,
which is caused when the second circuit board portion 414 is spaced
apart from the printed circuit board 40 since the base 500 is
brought into contact with the printed circuit board 40 earlier than
the second circuit board portion 414.
[0476] In the embodiment, in order to prevent the support portion
540 and the second circuit board portion 414 from being separated
from each other, the support portion 540 and the second circuit
board portion 414 may be adhered to each other using an adhesive,
for example.
[0477] Although the embodiment illustrates and describes the case
in which one support portion 540 protrudes from the lower surface
of the base 500, a plurality of support portions 540 may be formed
on the lower surface of the base 500.
[0478] That is, the support portions 540 may protrude from the
lower surface of the base 500, and the second circuit board portion
414 may be supported by the support portions 540.
[0479] Referring again to FIG. 32, the support portion 540 formed
on the base 500 and the second circuit board portion 414 are
coupled to the printed circuit board 40.
[0480] The image sensor 50 may be mounted on the printed circuit
board 40.
[0481] The printed circuit board 40 may be formed with a terminal
unit 42 for applying a voltage or a control signal to the lens
driving device 10. The terminal unit 42 is electrically connected
to the terminal unit 412 formed on the second circuit board portion
414.
[0482] A controller (not illustrated) may be formed on the printed
circuit board 40 to control the lens driving device 10.
[0483] The image sensor 50 may be mounted on the printed circuit
board 40. The image sensor 50 may be located so that the optical
axis thereof coincides with the lens module. Thereby, the image
sensor 50 may acquire light, which has passed through the lens
module. The image sensor 50 may output an image using light
introduced thereinto.
[0484] In an embodiment, the image sensor 50 may be a charge
coupled device (CCD), a metal oxide semiconductor (MOS), a CPD, or
a CID. However, the type of image sensor 50 is not limited
thereto.
[0485] The holder member 60 fixes the rim of the image sensor 50 so
that the image sensor 50 may be firmly fixed to the printed circuit
board 40.
[0486] In the embodiment, the holder member 60 serves to protect
the image sensor 50 from shocks or vibrations applied from the
outside by surrounding the image sensor 50.
[0487] The holder member 60 also serves to support the lens driving
device 10, in addition to fixing the rim of the image sensor 50 so
as to firmly fix the image sensor 50 to the printed circuit board
40.
[0488] In addition, a wall 62 may additionally protrude from the
upper surface of the holder member 60, and the infrared cutoff
filter 30 may be disposed on the wall 62.
[0489] Referring to FIGS. 32 and 34, the wall 62 of the holder
member 60 is disposed very close to the base 500, and thus, the
wall 62 of the holder member 60 and the base 500 may come into
contact with each other during a reliability test, which may cause
deterioration in the performance of the camera module 1.
[0490] In order to prevent this, an escape portion 530 may be
formed on the rear surface of the base 500. For example, the escape
portion 530 may take the form of a recess to prevent the wall 62
from coming into contact with the rear surface of the base 500.
[0491] Meanwhile, in the embodiment, the outer side surface of the
holder member 60 may face the support portion 540, which protrudes
or extends from the base 500.
[0492] FIG. 35 is a cross-sectional view illustrating the bonding
structure of the base corresponding to the holder member according
to an embodiment.
[0493] Referring to FIG. 35, the lens driving device 10 is bonded
to the holder member 60. The lens driving device 10 and the holder
member 60 are bonded together by, for example, a hybrid epoxy
hardener 560, which is cured by heat and light. Unlike this, both
the lens driving device 10 and the holder member 60 may be bonded
by, for example, a thermosetting adhesive or a photo-curing
adhesive.
[0494] In the embodiment, since the area over which the hybrid
epoxy hardener is applied between the holder member 60 and the base
500 is very narrow, the lens driving device 10 and the holder
member 60 may be easily separated from each other when transverse
force is applied between the lens driving device 10 and the holder
member 60.
[0495] In order to prevent this, the lower surface of the base 500
may be formed with adhesive accommodating recesses 550, which are
concavely formed in a direction facing the upper surface of the
base 500, and the adhesive 560 is accommodated in the adhesive
accommodating recesses 550.
[0496] In the embodiment, for example, the adhesive accommodating
recesses 550 may be arranged in a matrix form in the lower surface
of the base 500.
[0497] According to the above detailed description, the embodiments
may prevent errors in the assembly of a flexible printed circuit
board and an image sensor board and may reduce the assembly time by
supporting the flexible printed circuit board, which protrudes from
a lens driving device and is connected to the image sensor board
when the image sensor board and the lens driving device are coupled
to each other.
[0498] In addition, the embodiments prevent great deterioration in
the performance of a camera module caused when the image sensor
board and the lens driving device, which are bonded to each other,
are brought into contact with each other at facing portions thereof
during, for example, a reliability test.
[0499] In addition, it is possible to prevent the image sensor
board and the lens driving device from being easily separated from
each other by external shocks due to the small size of an adhesive
area of an adhesive disposed between the image sensor board and the
lens driving device.
[0500] Although only a few embodiments have been described above,
various other forms may be implemented. The technical contents of
the embodiments described above may be combined in various forms as
long as they are not incompatible technologies, and thus, may be
implemented in new forms.
INDUSTRIAL APPLICABILITY
[0501] A lens driving device and a camera module including the same
of the embodiments may include a fixing part between a lens barrel
and a bobbin, thereby preventing the lens barrel from being
separated from the bobbin or from tilting during a shock test.
Accordingly, the lens driving device and the camera module
including the same have industrial applicability.
* * * * *