U.S. patent application number 13/680015 was filed with the patent office on 2014-06-05 for objective lens driving unit, and optical pickup device and optical disc drive including the objective lens driving unit.
This patent application is currently assigned to Toshiba Samsung Storage Technology Korea Corporation. The applicant listed for this patent is Min-soo Kang, Young-bin Lee, Jae-kuon Yun. Invention is credited to Min-soo Kang, Young-bin Lee, Jae-kuon Yun.
Application Number | 20140157292 13/680015 |
Document ID | / |
Family ID | 48837376 |
Filed Date | 2014-06-05 |
United States Patent
Application |
20140157292 |
Kind Code |
A1 |
Lee; Young-bin ; et
al. |
June 5, 2014 |
OBJECTIVE LENS DRIVING UNIT, AND OPTICAL PICKUP DEVICE AND OPTICAL
DISC DRIVE INCLUDING THE OBJECTIVE LENS DRIVING UNIT
Abstract
Provided is an objective lens driving unit that includes a
moving structure including an objective lens and a driving coil, a
yoke and a fixed portion extending from the yoke, and a wire holder
that has a first surface and a second surface that is adjacent to
the first surface. The fixed portion of the yoke is integrally
bonded to the first surface, and a terminal unit comprising a
plurality of interconnection layers is embedded on the second
surface. The objective lens driving unit also includes a plurality
of suspension wires that connect the driving coil to the terminal
unit of the wire holder.
Inventors: |
Lee; Young-bin; (Suwon-si,
KR) ; Kang; Min-soo; (Seoul, KR) ; Yun;
Jae-kuon; (Suwon-si, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Lee; Young-bin
Kang; Min-soo
Yun; Jae-kuon |
Suwon-si
Seoul
Suwon-si |
|
KR
KR
KR |
|
|
Assignee: |
Toshiba Samsung Storage Technology
Korea Corporation
Suwon-si
KR
|
Family ID: |
48837376 |
Appl. No.: |
13/680015 |
Filed: |
November 17, 2012 |
Current U.S.
Class: |
720/681 |
Current CPC
Class: |
G11B 7/1374 20130101;
G11B 7/0933 20130101; G11B 7/0932 20130101 |
Class at
Publication: |
720/681 |
International
Class: |
G11B 7/1374 20060101
G11B007/1374 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 31, 2012 |
KR |
10-2012-0009748 |
Claims
1. An objective lens driving unit for an optical disc drive, the
objective lens driving unit comprising: a moving structure
comprising an objective lens and a driving coil; a yoke structure
comprising a magnet corresponding to the driving coil, a yoke
supporting the magnet, and a fixed portion extending from the yoke;
a wire holder comprising a first surface and a second surface that
is adjacent to the first surface, wherein the fixed portion of the
yoke structure is integrally bonded to the first surface by
molding, and a terminal unit comprising a plurality of
interconnection layers is embedded in the second surface; and a
plurality of suspension wires that connect the driving coil to the
terminal unit of the wire holder, wherein an opening is formed on
the first surface of the wire holder in which the fixed portion of
the yoke structure is embedded and the opening exposes the fixed
portion.
2. (canceled)
3. The objective lens driving unit of claim 1, wherein the
interconnection layers comprise an interconnection layer for
grounding which extends toward a corner between the first surface
and the second surface of the wire holder, and a protruding portion
which extends from the fixed portion of the yoke structure exposed
through the opening to the interconnection layer for grounding and
is electrically connected to the interconnection layer for
grounding.
4. The objective lens driving unit of claim 3, wherein the
protruding portion extends from the center of an edge of the fixed
portion.
5. The objective lens driving unit of claim 3, further comprising a
protection cover that protects the moving structure and which is
electrically connected to the interconnection layer for
grounding.
6. The objective lens driving unit of claim 3, wherein the
interconnection layer for grounding is located at the center of the
second surface and the other interconnection layers are disposed on
both sides of the interconnection layer for grounding.
7. An objective lens driving unit for an optical disc drive, the
objective lens driving unit comprising: a moving structure
comprising an objective lens and a driving coil; a yoke structure
comprising a magnet corresponding to the driving coil, a yoke
supporting the magnet, and a fixed portion extending from the yoke;
a wire holder comprising a first surface and a second surface that
is adjacent to the first surface, wherein the fixed portion of the
yoke structure is integrally bonded to the first surface by
molding, and a terminal unit comprising a plurality of
interconnection layers is embedded in the second surface; and a
plurality of suspension wires that connect the driving coil to the
terminal unit of the wire holder, wherein the terminal unit
comprises a terminal substrate that is embedded and fixed in the
wire holder, and the interconnection layers are formed on the
terminal substrate.
8. The objective lens driving unit of claim 1, wherein the
interconnection layers are directly embedded and fixed in the
second surface of the wire holder.
9. An optical pickup device comprising: a moving structure
comprising an objective lens and a driving coil; a static structure
comprising: a yoke structure comprising a magnet corresponding to
the driving coil, a yoke supporting the magnet, and a fixed portion
extending from the yoke, a wire holder comprising a first surface
and a second surface that is adjacent to the first surface, wherein
the fixed portion of the yoke structure is integrally formed by
molding on the first surface and a terminal unit comprising a
plurality of interconnection layers is embedded in the second
surface, and a plurality of suspension wires connecting the driving
coil to the interconnection layers; and a base that supports the
static structure and which comprises a light source and a
light-receiving device, wherein an opening is formed on the first
surface of the wire holder in which the fixed portion of the yoke
structure is embedded and the opening exposes the fixed
portion.
10. (canceled)
11. The optical pickup device of claim 9, wherein the
interconnection layers comprise an interconnection layer for
grounding which extends toward a corner between the first surface
and the second surface of the wire holder, and a protruding portion
which extends from the fixed portion of the yoke structure exposed
through the opening to the interconnection layer for grounding at
the corner and which is electrically connected to the
interconnection layer for grounding.
12. The optical pickup device of claim 11, wherein the protruding
portion extends from the center of an edge of the fixed
portion.
13. The optical pickup device of claim 12, wherein the fixed
portion is fixed on the second surface of the wire holder which is
adjacent to the first surface, and the protruding portion of the
fixed portion is electrically connected to the interconnection
layer for grounding through a corner between the first surface and
the second surface.
14. The optical pickup device of claim 9, wherein the terminal unit
comprises a terminal substrate that is embedded and fixed in the
wire holder, and the interconnection layers are formed on the
terminal substrate.
15. The optical pickup device of claim 9, wherein the
interconnection layers are directly embedded and fixed in the
second surface of the wire holder.
16. An optical disc drive comprising the optical pickup device of
claim 9.
17. (canceled)
18. The optical disc drive of claim 16, wherein a protruding
portion extends from the center of an edge of the fixed
portion.
19. The optical disc drive of claim 18, wherein the protruding
portion of the fixed portion is electrically connected to the
interconnection layer for grounding through a corner between the
first surface and the second surface.
20. The optical disc drive of claim 16, wherein the terminal unit
comprises a terminal substrate that is embedded and fixed in the
wire holder, and the interconnection layers are formed on the
terminal substrate.
21. An objective lens driving device for an optical disc drive, the
device comprising: a wire holder comprising a first surface and a
second surface that is adjacent to the first surface; a terminal
unit comprising a plurality of interconnection layers, the terminal
unit configured to be embedded in the second surface; and a yoke
configured to support a magnet, driving coil, and objective lens of
the driving device, to be integrally bonded to the first surface of
the wire holder by molding, and to extend beyond the second surface
of the wire holder and make contact with one of the interconnection
layers of the terminal unit.
Description
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims the benefit under 35 USC
.sctn.119(a) of Korean Patent Application No. 10-2012-0009748,
filed on Jan. 31, 2012 in the Korean Intellectual Property Office,
the entire disclosure of which is incorporated herein by reference
for all purposes.
BACKGROUND
[0002] 1. Field
[0003] The following description relates to an objective lens
driving unit, and more particularly, to an objective lens driving
unit that is easier to assemble.
[0004] 2. Description of Related Art
[0005] An objective lens driving unit of an optical pickup device
typically has a structure of a voice coil motor (VCM). The typical
objective lens driving unit includes a static structure including a
permanent magnet and a yoke, and a moving structure including a
driving coil and an objective lens. In a typical structure, the
moving structure is supported with respect to the static structure
by a plurality of suspension wires. The suspension wires also
function as an electrical connection for applying a driving voltage
to a driving coil to control focusing and tracking of the objective
lens.
[0006] An optical pickup device for a slim optical disc drive such
as that used in a notebook computer structurally consists of small
parts. Accordingly, assembling thereof is difficult, and product
characteristics may have a wide range of dispersion due to assembly
misalignment.
SUMMARY
[0007] In an aspect, there is provided an objective lens driving
unit for an optical disc drive, the objective lens driving unit
including a moving structure comprising an objective lens and a
driving coil, a yoke structure comprising a magnet corresponding to
the driving coil, a yoke supporting the magnet, and a fixed portion
extending from the yoke, a wire holder comprising a first surface
and a second surface that is adjacent to the first surface, wherein
the fixed portion of the yoke structure is integrally bonded to the
first surface by molding, and a terminal unit comprising a
plurality of interconnection layers is embedded in the second
surface, and a plurality of suspension wires that connect the
driving coil to the terminal unit of the wire holder.
[0008] An opening may be formed on the first surface of the wire
holder in which the fixed portion of the yoke structure is embedded
and the opening may expose the fixed portion.
[0009] The interconnection layers may comprise an interconnection
layer for grounding which extends toward a corner between the first
surface and the second surface of the wire holder, and a protruding
portion which extends from the fixed portion of the yoke structure
exposed through the opening to the interconnection layer for
grounding and is electrically connected to the interconnection
layer for grounding.
[0010] The protruding portion may extend from a center of an edge
of the fixed portion.
[0011] The objective lens driving unit may further comprise a
protection cover that protects the moving structure and which is
electrically connected to the interconnection layer for
grounding.
[0012] The interconnection layer for grounding may be located at
the center of the second surface and the other interconnection
layers may be disposed on both sides of the interconnection layer
for grounding.
[0013] The terminal unit may comprise a terminal substrate that is
embedded and fixed in the wire holder, and the interconnection
layers may be formed on the terminal substrate.
[0014] The interconnection layers may be directly embedded and
fixed in the second surface of the wire holder.
[0015] In an aspect, there is provided an optical pickup device
including a moving structure comprising an objective lens and a
driving coil, a static structure comprising a yoke structure
comprising a magnet corresponding to the driving coil, a yoke
supporting the magnet, and a fixed portion extending from the yoke,
a wire holder comprising a first surface and a second surface that
is adjacent to the first surface, wherein a fixed portion of the
yoke structure is integrally formed by molding on the first surface
and a terminal unit comprising a plurality of interconnection
layers is embedded in the second surface, and a plurality of
suspension wires connecting the driving coil to the interconnection
layers, and a base that supports the static structure and which
comprises a light source and a light-receiving device.
[0016] An opening may be formed on the first surface of the wire
holder in which the fixed portion of the yoke structure is embedded
and the opening may expose the fixed portion.
[0017] The interconnection layers may comprise an interconnection
layer for grounding which extends toward a corner between the first
surface and the second surface of the wire holder, and a protruding
portion which extends from the fixed portion of the yoke structure
exposed through the opening to the interconnection layer for
grounding at the corner and which is electrically connected to the
interconnection layer for grounding.
[0018] The protruding portion may extend from a center of an edge
of the fixed portion.
[0019] The fixed portion may be fixed on the second surface of the
wire holder which is adjacent to the first surface, and the
protruding portion of the fixed portion may be electrically
connected to the interconnection layer for grounding through a
corner between the first surface and the second surface.
[0020] The terminal unit may comprise a terminal substrate that is
embedded and fixed in the wire holder, and the interconnection
layers may be formed on the terminal substrate.
[0021] The interconnection layers may be directly embedded and
fixed in the second surface of the wire holder.
[0022] In an aspect, there is provided an optical disc drive
comprising the optical pickup device.
[0023] Other features and aspects may be apparent from the
following detailed description, the drawings, and the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a diagram illustrating an example of a CD/DVD
optical pickup device.
[0025] FIG. 2 is a diagram illustrating an example of an optical
pickup device.
[0026] FIG. 3 is a diagram illustrating an example of an objective
lens driving unit.
[0027] FIG. 4 is a diagram illustrating an example of a wire holder
used in an objective lens driving unit.
[0028] FIG. 5 is a diagram illustrating an example of a yoke
structure used in an objective lens driving unit.
[0029] FIG. 6 is a diagram illustrating an example of a terminal
unit used in an objective lens driving unit.
[0030] FIG. 7 is a diagram illustrating another example of a
terminal unit.
[0031] FIG. 8 is a diagram illustrating another example of a wire
holder and a yoke structure including the terminal unit of FIG.
7.
[0032] Throughout the drawings and the detailed description, unless
otherwise described, the same drawing reference numerals will be
understood to refer to the same elements, features, and structures.
The relative size and depiction of these elements may be
exaggerated for clarity, illustration, and convenience.
DETAILED DESCRIPTION
[0033] The following detailed description is provided to assist the
reader in gaining a comprehensive understanding of the methods,
apparatuses, and/or systems described herein. Accordingly, various
changes, modifications, and equivalents of the methods,
apparatuses, and/or systems described herein will be suggested to
those of ordinary skill in the art. Also, descriptions of
well-known functions and constructions may be omitted for increased
clarity and conciseness.
[0034] FIG. 1 illustrates an example of an optical pickup device
for CD and/or DVD.
[0035] Referring to FIG. 1, the optical pickup device includes a
light transmission system 10, a light source system 20 for
supplying a plurality of beams for regenerating and/or recording
information with respect to a medium 1, and a light receiving
system 30. For example, the light source system 20 may supply three
beams including a main beam and first and second sub beams located
on both sides of the main beam. The light receiving system 30 may
generate an electric signal, such as a data signal or a tracking
error signal (TES) for processing to regenerate information by a
light-receiving device 32. In this example, the light receiving
device 32 may include three light-receiving cells for receiving
three beams reflected by the medium 1.
[0036] The light source system 20 includes a light source 21 for
CD/DVD, and a diffraction device 22. A beam may be incident from
the light source 21 to a first beam splitter 13 through the
diffraction device 22. The diffraction device 22 may form a main
beam and .+-.1 order sub beams from a beam transmitted by the light
source 21 using diffraction effects.
[0037] The light receiving system 30 includes a light-receiving
device 32 for generating an electrical signal by detecting beams
that have been reflected from the medium 1 and that have passed
through the first beam splitter 13, and a sensing lens 31 for
focusing the main beam and the first and second sub beams located
on both sides of the main beam in an intensity with respect to the
light-receiving device 32.
[0038] The light transmission system 10 includes an objective lens
11 corresponding to the medium 1, path change mirrors 16 and 18, a
quarter wave plate (QWP) 15, a collimating lens 12, and a first
beam splitter 13. The first beam splitter 13 may reflect three
beams transmitted by the light source system 20 toward the
objective lens 11, and transmits light beams that return after
being reflected from the medium 1 to enter into the light receiving
system 30.
[0039] FIG. 2 illustrates an example of an optical pickup
device.
[0040] Referring to FIG. 2, an assembly base 100 includes a
plurality of optical parts. For example, the assembly base 100 may
be formed by aluminum die casting or plastic molding. The assembly
100 may have a predetermined thickness.
[0041] The assembly base 100 includes an objective lens driving
unit 200. The objective lens driving unit 200 includes the
objective lens 11 and a protecting cover 229 covering a surrounding
of the objective lens 11. In addition, the assembly base 100 may
also include the previously described optical parts, for example,
the beam splitter 13, the light source 21, the light-receiving
device 32, the beam splitter 13, the light source 21, and the
light-receiving device 32, which may be arranged as illustrated in
FIG. 1. Meanwhile, a shaft guide 101 that has a cylindrical hole
102a is formed on a side of the assembly base 100. Arms 102 extend
out from the shaft guide 101 and include the cylindrical hole 102a.
The shaft guide 101 may receive a guide shaft (not shown) of an
optical disc drive apparatus inserted therein.
[0042] FIG. 3 illustrates an example of the objective lens driving
unit 200 included in the optical pickup device illustrated in FIGS.
1 and 2. FIG. 4 illustrates an example of a wire holder 220
included in the objective lens driving unit 200. FIG. 5 illustrates
an example of a yoke structure.
[0043] Referring to FIGS. 3 and 4, the objective lens 11 is
installed at the center of an upper surface of a frame 210 of a
moving structure. In this example, the frame 210 is a square frame.
A surrounding of the objective lens 11 is covered by the protecting
cover 229. First driving coils 212 for focusing operation of the
objective lens 11 are installed on inner circumference surfaces of
rectangular through-holes 211 and disposed on both sides of the
frame 210. In addition, second driving coils 213 for tracking
operations are attached on an outer surface of the frame 210.
[0044] In this example, the static structure includes permanent
magnets 224 and a yoke structure that includes surrounding yokes
225 and central yokes 226 on which the permanent magnets 224 are
fixed. The surrounding yokes 225 face the second driving coils 213,
respectively, and are in the form of a column. The central yokes
226 are respectively located at the center of each of the
through-holes 211. The permanent magnets 224 are fixed on an inner
surface of the surrounding yokes 225 and face the second driving
coils 213, respectively.
[0045] FIG. 5 illustrates an example of a side of a yoke structure.
Referring to FIG. 5, a fixed portion 223 is embedded and fixed in
an upper surface of a wire holder 220. A connection portion 222 is
disposed between the yoke structure and the fixed portion 223. The
connection portion 222 is coupled to an end of the protecting cover
229. Accordingly, the protecting cover 229 and the surrounding yoke
225 and the central yoke 226 are electrically connected to each
other, and are grounded to the outside through an interconnection
layer 221g for grounding.
[0046] Referring again to FIGS. 3 and 4, the static structure
includes the wire holder 220, the surrounding yokes 225 and the
central yokes 226, and the permanent magnets 224. The static
structure supports the frame 210 of the moving structure through
suspension wires 230. On a rear surface of the wire holder 220 is a
terminal unit 221 for supplying an electrical signal to the first
and second driving coils 212 and 213.
[0047] According to various aspects, the terminal unit 221 may
include a plurality of interconnection layers 221a to 221g that are
embedded and fixed in the second surface of the wire holder 220. An
example of the interconnection layers 221a to 221g is illustrated
in FIG. 6. An interconnection layer is used in the form of a lead
frame in an extraction process for manufacturing a wire holder. For
example, the wire holder 220 having the rear surface in which the
interconnection layers 221a to 221g are embedded and fixed may be
manufactured by injection molding. In this example, the
interconnection layers 221a to 221g may be located as inserts in
given locations within the mold.
[0048] Rear ends of the suspension wires 230 passing through both
sides of the wire holder 220 are fixed to one side of terminals
221a' to 221f' of the interconnection layers 221a to 221f which are
located on left and right-hand side edges of the rear surface of
the wire holder 220. In addition, lower ends of the interconnection
layers 221a to 221g are aligned in one row on a lower portion of
the rear surface of the wire holder 220. The other side of the
terminals of the interconnection layers 221a to 221g are connected
to an external circuit. In this example, the interconnection layer
221g is for grounding and includes a terminal 221g' that is
adjacent to a protruding portion 223a of the fixed portion 223. The
terminal 221g' is adjacent to a protruding portion 223a protruding
from the fixed portion 223, and the terminal 221g' and the
protruding portion 223a are connected to each other, for example,
by a solder 228.
[0049] Accordingly, the protecting cover 229 and the surrounding
yokes 225 are connected to a grounding portion of an external
circuit, and thus, may protect a circuit of an optical pickup
device from an external electric impact, such as ESD. In this
example, the protruding portion 223a of the fixed portion 223 is
exposed to the outside through an opening 220a formed on the upper
surface of the wire holder 220. Also, the terminal 221g' for
grounding and the protruding portion 223a are electrically
connected to each other by the solder 228 at the opening 220a.
[0050] Meanwhile, the other ends of the suspension wires 230 are
electrically connected to the first driving coils 212 while being
fixed on both side surfaces of the frame 210.
[0051] According to various aspects, the terminal unit 221 includes
the interconnection layers 221a to 221f that are directly embedded
in the wire holder 220. However, as illustrated in FIG. 7, a
terminal unit may include a terminal substrate 221h embedded in the
wire holder 220, and the interconnection layers 221a to 221f may be
formed on the terminal substrate 221a. As another example, the
terminal substrate 221h may be embedded in the second surface, that
is, the rear surface of the wire holder 220 as illustrated in FIG.
8. The terminal substrate 221a may be used as an insert in
manufacturing the wire holder 220 together with the fixed portion
223 having the yoke structure. For example, the wire holder 220
having the rear surface on which the terminal substrate 221h is
embedded, may be manufactured by injection molding, and the
terminal substrate 221h and the fixed portion 223 may be located as
inserts at given locations inside a mold.
[0052] According to various aspects, a yoke structure and a
terminal unit of the optical disc drive are integrally fixed with
respect to a wire holder by molding. Accordingly, a separate
process is not needed to fix the yoke structure and the terminal
unit with respect to the wire holder. In addition, because the yoke
structure and the terminal unit are fixed as one body through the
injection molding process for forming the wire holder, a
characteristics dispersion range of products may be reduced. In
addition, an assembling process for binding the yoke structure and
the terminal unit is not needed, and in a production line, the yoke
structure and the terminal unit are handled as one component.
Accordingly, manufacturing costs may be reduced compared to in the
conventional optical disc drive.
[0053] A number of examples have been described above.
Nevertheless, it will be understood that various modifications may
be made. For example, suitable results may be achieved if the
described techniques are performed in a different order and/or if
components in a described system, architecture, device, or circuit
are combined in a different manner and/or replaced or supplemented
by other components or their equivalents. Accordingly, other
implementations are within the scope of the following claims.
* * * * *