U.S. patent application number 12/768893 was filed with the patent office on 2010-08-19 for printed board, image pickup apparatus and camera.
This patent application is currently assigned to Konica Minolta Opto Inc.. Invention is credited to Masahiro Takashima, Tougo TERAMOTO.
Application Number | 20100206620 12/768893 |
Document ID | / |
Family ID | 37678679 |
Filed Date | 2010-08-19 |
United States Patent
Application |
20100206620 |
Kind Code |
A1 |
TERAMOTO; Tougo ; et
al. |
August 19, 2010 |
Printed Board, Image Pickup Apparatus and Camera
Abstract
The present invention relates to a bendable printed board, an
image pickup apparatus, and a camera. The bendable printed board is
provided with: a first end connected to a moving body movable in an
arbitral direction within a predefined plane; a second end
connected to a fixed body with slack providing movability to the
moving body; and a slit formed on at least a part of a slack
portion of the printed board.
Inventors: |
TERAMOTO; Tougo; (Tokyo,
JP) ; Takashima; Masahiro; (Tokyo, JP) |
Correspondence
Address: |
COHEN, PONTANI, LIEBERMAN & PAVANE LLP
551 FIFTH AVENUE, SUITE 1210
NEW YORK
NY
10176
US
|
Assignee: |
Konica Minolta Opto Inc.
Tokyo
JP
|
Family ID: |
37678679 |
Appl. No.: |
12/768893 |
Filed: |
April 28, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11478779 |
Jun 29, 2006 |
7734083 |
|
|
12768893 |
|
|
|
|
Current U.S.
Class: |
174/254 |
Current CPC
Class: |
H04N 5/2251 20130101;
H05K 1/028 20130101; H05K 2201/09063 20130101 |
Class at
Publication: |
174/254 |
International
Class: |
H05K 1/00 20060101
H05K001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 8, 2005 |
JP |
2005-199866 |
Claims
1. A bendable printed board comprising: a main body on which a slit
is formed; a first end connected to a moving body which is movable
in at least a first direction, where the first direction is
perpendicular to a direction in which the slit extends; and a
second end connected to a fixed body with a slack formed on the
main body so as to provide movability to the moving body, wherein
the slit is formed on at least a part of the slack of the main body
and extends along the slack.
2. The printed board of claim 1, wherein the slit is an
open-slit.
3. The printed board of claim 1, wherein the printed board is
arranged to turn back on the slack.
4. The printed board of claim 1, wherein the moving body is movable
in the first direction and a second direction which is
perpendicular to the first direction.
5. The printed board of claim 1, wherein the main body includes a
folding on the slack, where the folding extends in a direction
across the slit.
6. A bendable printed board comprising: a main body on which at
least one slit is formed; a first end connected to a moving body
which is movable in at least a first direction, where the first
direction is perpendicular to a direction in which the at least one
slit extends; and a second end connected to a fixed body with a
slack formed on the main body so as to provide movability to the
moving body; and a plurality of wirings formed on the main body and
connected between the first end and the second end, wherein the at
least one slit is arranged at at least a part of the slack between
the plurality of wirings.
7. The printed board of claim 6, wherein the slit is an
open-slit.
8. The printed board of claim 6, wherein the printed board is
arranged to turn back on the slack.
9. The printed board of claim 6, wherein the moving body is movable
in the first direction and a second direction which is
perpendicular to the first direction.
10. The printed board of claim 6, wherein the main body includes a
folding on the slack, where the folding extends in a direction
across the slit.
11. A moving apparatus comprising: a moving body which is movable
in at least a first direction; and a bendable printed board
comprising: a main body on which a slit is formed; a first end
connected to the moving body; and a second end connected to a fixed
body with a slack formed on the main body so as to provide
movability to the moving body, wherein the slit is formed on at
least a part of the slack of the main body and extends along the
slack, and the first direction is perpendicular to a direction in
which the slit extends.
12. The moving apparatus of claim 11, wherein the slit is an
open-slit.
13. The moving apparatus of claim 11, wherein the slack is bent at
an angle of 90 degrees or more.
14. The moving apparatus of claim 11, wherein the printed board is
arranged to turn back on the slack.
15. The moving apparatus of claim 1, wherein the moving body is
movable in the first direction and a second direction which is
perpendicular to the first direction.
16. The moving apparatus of claim 1, wherein the main body includes
a folding on the slack, where the folding extends in a direction
across the slit.
17. A moving apparatus comprising: a moving body which is movable
in at least a first direction; and a bendable printed board
comprising: a main body on which at least one slit is formed; a
first end connected to the moving body which is movable in at least
a first direction, where the first direction is perpendicular to a
direction in which the at least one slit extends; a second end
connected to a fixed body with a slack formed on the main body so
as to provide movability to the moving body; and a plurality of
wirings formed on the main body and connected between the first end
and the second end, wherein the at least one slit arranged at at
least a part of the slack between the plurality of wirings.
18. The moving apparatus of claim 17, wherein the slit is an
open-slit.
19. The moving apparatus of claim 17, wherein the slack is bent at
an angle of 90 degrees or more.
20. The moving apparatus of claim 17, wherein the printed board is
arranged to turn back on the slack.
21. The moving apparatus of claim 17, wherein the moving body is
movable in the first direction and a second direction which is
perpendicular to the first direction.
22. The moving apparatus of claim 17, wherein the main body
includes a folding on the slack, extending in a direction across
the slit.
Description
[0001] This application is a Continuation of U.S. patent
application Ser. No. 11/478,779, filed Jun. 29, 2006, which is
based on Japanese Patent Application No. 2005-199866 filed on Jul.
8, 2005, in Japanese Patent Office, the entire content of which is
hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a bendable printed board
that is suitable when connecting to a moving body organized to be
capable of moving in a prescribed plane and relates to an image
pickup apparatus providing camera shake correction by using the
moving body including an image pickup element and further relates
to an camera including the image pickup apparatus.
BACKGROUND
[0003] Active camera shake correction technologies have so far been
put into practical use to obtain a clear image by correcting
misalignment of an optical axis caused by camera shake. There is
known three types of camera shake correction technologies including
the first type that a part of an image pickup optical system is
moved, the second type that the whole of the image pickup optical
system is moved and the third type that an image pickup element is
moved.
[0004] Among these active camera shake correction technologies, the
third type of technology providing the camera shake correction that
an image pickup element moves in a plane perpendicular
substantially to an optical axis of the image pickup optical
system, has an advantage that the technology can cope with all
imaging optical systems to be used.
[0005] With respect to the third type of technology that the image
pickup element moves, TOKUKAI No. 2003-110929 discloses an image
pickup apparatus provided with: a printed board in which an image
pickup element and another electric component arranged and which
moves with the image pickup element; and a flexible printed board
having one end connected to the printed board.
[0006] The image pickup apparatus disclosed in the aforesaid patent
document is provided to improve space efficiency of the total
device. However, the flexible printed board for connecting between
the image pickup element that moves and another printed board that
does not move are incorporated to the image pickup apparatus with
sufficient slack as illustrated, and the image pickup apparatus
needs an enough space for this slack.
[0007] The greater an amount of this slack of the flexible printed
board is, the more the load resistance caused by the printed board
when an image pickup element and its peripheral member both
representing a moving body can be reduced, resulting in a
contribution to downsizing of an actuator and to electric power
saving. However, a space to slacken the printed board needs to be
secured, resulting in an obstacle for further downsizing.
SUMMARY
[0008] In view of the problems stated above, an object of the
present invention is to obtain a flexible printed board reducing
the load resistance of a moving body such as, for example, an image
pickup element and its peripheral member even when an amount of
slack is small, and to obtain an image pickup apparatus with a
camera shake correction mechanism of a type that an image pickup
element moves, being downsized and saving electric power
realizing.
[0009] The above problems are solved by the following embodiment
that: a printed board having a first end connected to a moving body
movable in an arbitral direction within a predefined plane; a
second end connected to a fixed body with slack providing
movability to the moving body; and a slit formed in a predefined
area on the printed board.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Embodiments will now be described, by way of example only,
with reference to the accompanying drawings which are meant to be
exemplary, not limiting, and wherein like elements numbered alike
in several Figures, in which:
[0011] FIG. 1 is a schematic structural diagram of a camera
employing an image pickup apparatus according to the present
embodiment;
[0012] FIG. 2 is an exploded perspective view for composition of an
image pickup apparatus according to the present embodiment;
[0013] FIG. 3 is a sectional view taken on line C-C of the image
pickup apparatus shown in FIG. 2;
[0014] FIG. 4 is a sectional view taken on line D-D of the image
pickup apparatus shown in FIG. 2;
[0015] FIG. 5 is a sectional view taken on line E-E of the image
pickup apparatus shown in FIG. 2;
[0016] FIG. 6 is a block diagram showing an electrical structure of
a drive control circuit for camera shake correction according to
the present embodiment;
[0017] Each of FIGS. 7(a), 7(b1), 7(b2) and 7(b3) is a diagram
showing a driving principle of an actuator;
[0018] Each of FIGS. 8(a) to 8(c) is a development elevation
showing an example of a shape of a flexible printed board shown in
FIG. 4;
[0019] FIG. 9 is a perspective view showing the first board, the
second board and a flexible printed board drawn out;
[0020] Each of FIGS. 10(a) to 10(c) is a diagram showing another
example of the flexible printed board;
[0021] Each of FIGS. 11(a) and 11(b) is a diagram showing another
example of an image pickup optical system to which a bendable
printed board according to the present embodiment is applied;
[0022] Each of FIGS. 12(a) to 12(c) is a diagram showing a shape of
the flexible printed board which served as a test sample;
[0023] FIG. 13 is a perspective view of the flexible printed board
folded to be a side view shown in FIG. 12(a);
[0024] FIG. 14 is a diagram showing measurement conditions;
[0025] FIG. 15 is a graph showing measurement results of restoring
force;
[0026] FIG. 16 is a diagram showing another example of a flexible
printed board according to the present invention;
[0027] Each of FIGS. 17(a) to 17(d) is a diagram showing another
example of a flexible printed board according to the present
invention; and
[0028] Each of FIGS. 18(a) and 18(b) is a diagram showing another
example of a flexible printed board according to the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0029] Preferred embodiments according to the present invention are
described below. [0030] (Item 1) A bendable printed board
including: a first end connected to a moving body movable in an
arbitral direction within a predefined plane; a second end
connected to a fixed body with slack providing movability to the
moving body; and a slit formed on at least a part of a slack
portion of the printed board and extending along the slack. [0031]
(Item 2) The printed board described in Item 1 in which the slit is
an open-slit. [0032] (Item 3) The printed board described in Item 1
or 2 in which the printed board is arranged to turn back on the
slack portion. [0033] (Item 4) The printed board of any one of
Items 1 to 3 in which the slack portion has a thickness in a range
of 0.02 mm to 0.2 mm. [0034] (Item 5) A bendable printed board
including: a first end connected to a moving body movable in an
arbitral direction within a predefined plane; a second end
connected to a fixed body with slack providing movability to the
moving body; a plurality of wirings connected between the first end
and the second end; and at least one slit arranged at at least a
part of a slack portion between the plurality of wirings. [0035]
(Item 6) The printed board described in Item 5 in which the slit is
an open-slit. [0036] (Item 7) The printed board described in Item 5
or 6 in which the printed board is arranged to turn back on the
slack portion. [0037] (Item 8) The printed board described in any
one of Item 5 to 7 in which the slack portion has a thickness in a
range of 0.02 mm to 0.2 mm. [0038] (Item 9) An image pickup
apparatus including: an image pickup optical system for guiding a
subject light flux; a movable section including an image pickup
element for photoelectrically converting the light flux guided by
the image pickup optical system; and a bendable printed board. The
bendable printed board includes a first end connected to the
movable section for inputting signal from or outputting signal to
the image pickup element; a second end connected to a fixed body
with slack; and a slit formed on at least a part of a slack portion
of the printed board and extending along the slack. The movable
section is movable in an arbitral direction within a plane
perpendicular to an optical axis of the image pickup optical
system. [0039] (Item 10) The image pickup apparatus described in
Item 9 in which the slit is an open-slit. [0040] (Item 11) The
image pickup apparatus described in Item 9 or 10 in which the slack
portion is bent at an angle of 90 degrees or more. [0041] (Item 12)
The image pickup apparatus described in any one of Items 9 to 11 in
which the printed board is arranged to turn back on the slack
portion. [0042] (Item 13) An image pickup apparatus including: an
image pickup optical system for guiding a subject light flux; a
movable section including an image pickup element for
photoelectrically converting the light flux guided by the image
pickup optical system; and a bendable printed board. The bendable
printed board includes a first end connected to the movable section
for inputting signal from or outputting signal to the image pickup
element; a second end connected to a fixed body with slack; and a
plurality of wirings connected between the first end and the second
end; and at least one slit arranged at at least a part of a slack
portion between the plurality of wirings. The movable section is
movable in an arbitral direction within a plane perpendicular to an
optical axis of the image pickup optical system. [0043] (Item 14)
The image pickup apparatus described in Item 13 in which the slit
is an open-slit. [0044] (Item 15) The image pickup apparatus
described in Item 13 or 14 in which the slack portion is bent at an
angle of 90 degrees or more. [0045] (Item 16) The image pickup
apparatus described in any one of Item 13 to 15 in which the
printed board is arranged to turn back on the slack portion. [0046]
(Item 17) A camera comprising the image pickup apparatus described
in any one of Items 9 to 16.
[0047] The present invention provides a flexible printed board for
connecting to a moving body movably in an arbitral direction in the
prescribed plane with reduced load resistance for the movement even
when a slacked amount of the flexible printed board is small. When
an embodiment according to the invention is applied to camera shake
correction mechanism of a type to move an image pickup element of
an image pickup apparatus, it is possible to obtain an image pickup
apparatus realizing further downsizing and electric power
saving.
[0048] While the preferred embodiments of the present invention
have been described using specific terms, such description is for
illustrative purposes only, and it is to be understood that changes
and variations may be made without departing from the sprit or
scope of the appended claims.
[0049] There will be explained in detail as follows an embodiment
according to the invention, however, it does not limit the scope of
the invention.
[0050] In the meantime, the printed board according to the present
invention is provided to be used by connecting to a moving body
movable in an arbitral direction in a prescribed plane
independently of a use, and an explanation will be given with an
example that the printed board according to the invention is
applied to an image pickup apparatus having a camera shake
correction mechanism of a type that an image pickup element moves
as a moving body.
[0051] FIG. 1 is a schematic structural diagram of a camera
employing an image pickup apparatus according to the present
embodiment.
[0052] As shown in FIG. 1, the image pickup apparatus according to
the present embodiment is mounted on camera 1 provided with main
body 2 and image pickup apparatus 10, to be used. The image pickup
apparatus 10 is provided with an optical unit including plural
lenses and a lens barrel, and an image pickup unit including
therein a camera shake correction function provided with an image
pickup element that is connected to the optical unit to be used.
The optical unit is provided to move plural lenses and to perform
at least one of zooming operation and focusing operation. The image
pickup unit is arranged so that image pickup element 15 is moved as
shown with arrows 6X and 6Y in FIG. 1 to correct deviation of an
optical axis, when camera 1 is shaken in the course of
photographing and an optical axis of the optical unit is deviated
from the position shown with L in FIG. 1 as shown with arrows 5X
and 5Y in FIG. 1.
[0053] The image pickup unit having therein the aforesaid camera
shake correction function will be explained as follows.
[0054] FIG. 2 is an exploded perspective view for composition of an
image pickup apparatus according to the present embodiment. FIG. 3
is a sectional view taken on line C-C of the image pickup apparatus
shown in FIG. 2. FIG. 4 is a sectional view taken on line D-D of
the image pickup apparatus shown in FIG. 2. FIG. 5 is a sectional
view taken on line E-E of the image pickup apparatus shown in FIG.
2. Incidentally, in the following drawings, an explanation will be
given by giving the same symbols to members with the same
functions, for avoiding overlapping of explanation.
[0055] The image pickup unit is provided with base member 11 that
serves as a basis, first stage 13 that moves in the horizontal
direction (hereinafter referred to as X-axis direction) for the
base member 11, second stage 12 that moves in the vertical
direction (hereinafter referred to as Y-axis direction for
illustration) that is perpendicular to the movement direction
(X-axis direction) of the first stage 13, image pickup element 15
that is fixed on the second stage 12 and with PSD holder 14 having
thereon PSD representing a position detecting element that detects
an amount of movement of the first and second stages fixed on the
base member (hereinafter referred to as PSD).
[0056] Further, the base member 11 that shakably supports the image
pickup element 15, the first stage 13, the second stage 12 and PSD
holder 14 are positioned around the image pickup element 15
(including printed board processing information coming from the
image pickup element) and are arranged to fill the excessive space
of the outline of a bottom surface of lens barrel 3 and the outline
of the image pickup element 15.
[0057] The base member 11 is a metal frame that is provided to be
in a plate almost perpendicular to the direction of optical axis L
(hereinafter referred to as Z-axis direction), and has, at its
central portion, large hole 24 for an optical axis. On the base
member 11, there are provided PSD holder fixing hole 25 for fixing
the PSD holder 14, lens tube fixing hole 26 for fixing the base
member 11 to lens tube 3 and pressure spring hook 27 for fixing a
pressure spring hooked between the base member 11 and the first
stage 13.
[0058] As shown in FIG. 2 and FIG. 3, the base member 11 is fixed
by adjusting screw 33 and adjusting spring 21 between three fixing
sections 20 provided at three locations around the lens barrel 3 in
order to connect the image pickup unit to the optical unit so that
a position for lens barrel 3 may be adjusted (by tilting or by
shifting in the lens back side). A distance between the base member
11 and a bottom surface of the lens barrel 3 and its inclination
can be adjusted by adjusting spring 21 used for the fixing section
20, and thereby, an optical axis between the optical unit and the
imaging unit can be adjusted.
[0059] On the base member 11, there are provided rod-supporting arm
29 and a positioning arm (not shown) in the Z-axis direction. On
the rod-supporting arm 29, there is provided a first actuator
having the structure wherein piezoelectric element 57 is fixed on
the end of vibration transmission rod 28 and weight 30 is fixed on
the other end of the piezoelectric element 57. The first actuator
is fixed on the base member 11, in the direction in which the
vibration transmission rod 28 is extended in the X-axis direction
under the state where the weight 30 is in contact with the
positioning arm, with both end portions of the vibration
transmission rod 28 engaged with the rod-supporting arm. For
adhesion between the rod-supporting arm 29 and the vibration
transmission rod 28, it is preferable to use adhesive agents such
as silicone adhesive agents in which elasticity remains even after
hardening. For adhesion between the positioning arm 29 and weight
30, soft rubber type adhesives or silicone-containing adhesives are
preferably used.
[0060] As shown in FIG. 4, on a top surface of each of two
rod-supporting arm 29 on the base member 11, there is provided
protrusion 84 that extends in the Z-axis direction. The protrusion
84 is engaged with movement restricting hole 52a of the first stage
13 in the course of assembling.
[0061] The first stage 13 is arranged to be closer to an image
plane than the base member 11 is, in the optical axis direction
(Z-axis direction). The first stage 13 is provided with an aluminum
rectangular frame having thereon opening 51 for accepting second
stage 12, in the almost same plane. On the first stage 13, there
are provided first rod touching section 53 that comes in contact
with vibration transmission rod 28 for the first actuator 59 fixed
on the base member 11, second rod touching section 54 that comes in
contact with vibration transmission rod 47 for the second actuator
44 fixed on the second stage described later, pressure spring hook
56 on which pressure spring 55 is hooked between the pressure
spring hook 27 of the base member 11 and movement restricting hole
52a.
[0062] In the first rod touching section, vibration transmission
rod 28 of the first actuator 59 is interposed vertically by cap 32
representing a separate member and spring 31, and is connected to
the first actuator slidably along the vibration transmission rod
28. One end of the cap 32 is hooked on the first stage, then the
central portion of the cap 32 comes in contact with the vibration
transmission rod 28, and the other end thereof is pulled by
interposing spring 31, to be fixed on the first rod touching
section of the first stage. A contact pressure between the cap 32
and the vibration transmission rod 28 is about double the force of
interposing spring 31. The interposing spring 31 is a torsion coil
spring. Both arms and a central circular arc portion of the
interposing spring 31 are hooked on two hooks of the cap 32 and on
a spring hook of the first stage 13.
[0063] Movement restricting hole 52a engages loosely with
protrusion 84 on the tip of rod-supporting arm 29 of base member 11
(see FIG. 4). The movement restricting hole 52a is an elongated
hole extended in the direction of movement (X-axis direction) for
determining an amount of movement of the first stage 13, and it
engages with the protrusion in the direction of shorter side
(Y-axis direction) so that the first stage may move only in the
X-axis direction, and its both ends restrict the movement. Further,
it prevents that the vibration transmission rod 28 and the first
stage 13 move (drop off) in the direction of shorter side of the
movement restricting hole (Y-axis direction).
[0064] As shown in FIG. 5, owing to the pressure spring 55 hooked
on pressure spring hooks 27 and 56 provided respectively on the
base member 11 and the first stage 13 in the course of assembling,
the first stage 13 is urged in the direction to approach the base
member 12, and it prevents that the first stage 13 rotates on the
center of the vibration transmission rod 28 of the first stage
13.
[0065] Second stage 12 is casing 40 that is made of conductive
resin and is equipped with opening 41 on its bottom, and it holds
image pickup element 15, radiator plate 16, low pass filter 65 and
second actuator 44. The radiator plate 16 comes in contact with a
back side of the image pickup element 15 to be fixed on the second
stage 12 to cover the opening formed by surrounding wall 40 of the
second stage 12. The low pass filter 65 that is positioned to be
close contact with image pickup element 15 through a space frame
positioned in front of the image pickup element is pressed against
the radiator plate 16 from the front side.
[0066] The second stage 12 holds second actuator 44. The second
actuator 44 is stuck to supporting arm 45 provided on the side of
the casing 40 to be held. Weight 46 is stuck to the second stage 12
under the condition that the tip and the very end (on the
piezoelectric element 55 side) of vibration transmission rod 47 are
subjected to axial fitting with two rod-supporting arms of the
second stage 12, and weight 46 is in contact with positioning
surface 45a (see FIG. 3) provided equally in the second stage. For
adhesion for vibration transmission rod 60, adhesive agents in
which elasticity remains even after hardening, such as silicone
adhesives are preferably used, while, for contact for weight 58,
soft rubber type adhesives or silicone-containing adhesives are
preferably used, in the same way as in adhesion for the aforesaid
first actuator 59.
[0067] The second actuator 44 of the second stage 12 is interposed
between the second rod touching section 54 and cap 48. As a result,
friction combination is carried out under the state that the second
stage 12 is arranged in opening 51 of the first stage 13. Holding
spring 49 is used for fixing the second rod touching section 54 and
cap 48. One end of the cap 48 is hooked by the second rod touching
section 54, the central portion of the cap 48 touches vibration
transmission rod 47, and the other end of the cap 48 is pulled by
the holding spring 49. Contact pressure between the cap 48 and the
vibration transmission rod 47 is about double the force of the
holding spring 49 to be used. The holding spring 49 is a torsion
coil spring that is the same as one used in the first actuator 59.
Both ends of the holding spring 49 are hooked on two hooks of the
cap 48, and the central portion of the straight portion thereof is
hooked on a spring hook of the second rod touching section 54, so
that the holding spring 49 fixes both of the cap 48 and the second
rod touching section 54.
[0068] The second stage 12 has, on a part thereof, direction basis
portion 42 that is made of metal. The direction basis portion 42 is
in contact with base member 11 and first stage 13, through rigid
spheres 43 which are respectively located on both two sides of the
direction basis portion. Pressure spring 55 that is hooked between
the first stage 13 and the base member 11 restrains rotations of
two stages 12 and 13 on a vibration transmission rod being coupled
through friction with each of the stages 12 and 13.
[0069] As shown in FIGS. 3 to 5, first board 17 is provided on a
back surface of radiator plate 16. Image pickup element 15 is
arranged on the first board 17 (movable portion), with terminal
portions of the image pickup element 15 passing through the through
holes formed on the radiator plate 16. For detecting a position of
the image pickup element 15, on the back side of the first board
17, there are mounted holder 70 housing therein two infrared LEDs
82X and 82Y, an image pickup element driver, and a part of image
signal output circuits of the image pickup element such as a
preamplifier for processing photoelectric signals coming from the
image pickup element and a color separation circuit, a white
balance adjusting circuit and an analog processing circuit.
[0070] The two infrared LEDs 82X and 82Y are held on the holder 70
so that the direction of movement to be detected (rod) may be
perpendicular to the direction of a light source. On the holder,
there are provided slits 71X and 71Y to be away from LEDs 82
respectively, and rays of light emitted respectively from LEDs 82
pass through slits 71X and 71Y to be converted into line light
sources.
[0071] Bendable flexible printed board 67 that connects image
pickup element 15 and LEDs 82X and 82Y to second board 18 is
connected to the first board 17.
[0072] The flexible printed board 67 is connected to second board.
18 in a way that the flexible printed board 67 is bent toward the
front side in the optical axis direction once immediately after it
leaves the first board 17 in the horizontal direction, and the
flexible printed board 67 is further turns back to be bent again at
the position of the second board 18 in the horizontal direction to
have a slack (see FIG. 4).
[0073] PSD holder 14 is fixed to base member 11 to surround the
first stage 13 connected to the base member, the second stage 12
and image pickup element 15 (including radiator plate 16 and the
first board 17), and it houses elements (first and second PSD 62X
and PSD 62Y) which detect an amount of movement of the second
stage. A light-receiving surface of each of PSD 62X and 62Y is
perpendicular to a light flux of each of LED 82X and 82Y on the
second stage 13 through a slit extending horizontally on XY plane
provided on arrangement sections 61X and 61Y of the light-receiving
surface.
[0074] The second board 18 is positioned on the back surface of an
image forming surface, and is fixed on the PSD holder 14 so that an
opening on the back surface of the PSD holder 14 may be covered,
and it is wire-connected by the first board 17 and flexible printed
board 67.
[0075] On the second board 18, there are mounted a circuit that
processes signal coming from image pickup element 15 or from first
board 17 and a circuit that controls two linear actuators based on
position signals of the second stage from PSD and on gyro signals.
Two gyro signals whose detection directions are perpendicular to
each other are inputted the second board from gyro board (not
shown). Further, linear actuator control signals and processed
image pickup element signal are outputted from the second
board.
[0076] In the mean time, with respect to the optical system
arranged on the lens barrel 3 side, it is provided with a known
single-focus optical system or a zoom optical system, and a
constituting lens group and an actuator for moving the lens group
in the optical axis direction for zooming and focusing are
provided, though details are omitted.
[0077] Next, operations of an image pickup apparatus according to
the embodiment of the invention will be explained as follows.
[0078] FIG. 6 is a block diagram showing an electrical structure of
a drive control circuit for camera shake correction according to
the present embodiment.
[0079] The control circuit controls totally gyro element 90 that
detects deviation 5 of optical axis L entering lens barrel 3, and
outputs angular velocity signals and PSD 62X and 62Y that detect a
position of the second stage 12 (including image pickup element
15), and it is provided with microcomputer 102 that calculates an
amount of movement and an existing position based on inputted
signals and drive circuit 104 that generates driving pulses with
prescribed frequency based on drive signals coming from the
microcomputer. The driving pulses generated from the drive circuit
104 are outputted to the first and second actuators 30 and 46 to
move to the first and second stages 12 and 13 along actuators.
[0080] The gyro element 90 is fixed on lens barrel 3, and it
detects the angular velocity in each of two axial directions
(X-axis direction and Y-axis direction) and outputs it to
microcomputer 102.
[0081] When angular velocity signals are inputted in microcomputer
102 from the gyro element 90, the microcomputer 102 calculates,
from focal length signals of the optical system, an amount of
movement and a moving speed of the image on the image pickup
element (on the image forming surface) caused by the deviation.
Based on the calculated moving speed and the position of the second
stage 12 (image pickup element 15), supply voltage with prescribed
frequency to be impressed on each of two linear actuators is
determined. Namely, the microcomputer 102 calculates a position
where the image pickup element 15 should exist originally, based on
a position where the second stage 12 (image pickup element 15)
calculated based on signals inputted from PSD 62X and 62Y is
existing presently and on angular velocity signals inputted from
gyro element 90, then, compares a difference from the present
position, and conducts feedback control to move the stage so that
the image pickup element 15 may return to the position where it
should exist originally.
[0082] The drive circuit 104 receives signals from microcomputer
102, and outputs drive pulses with frequency that is about 70% of
resonance frequency of actuators 30 and 46. The drive pulses are
impressed on piezoelectric elements 57 and 55, and move the first
and second stages along vibration transmission rods 28 and 47 under
the following principle.
[0083] Each of FIGS. 7(a), 7(b1), 7(b2) and 7(b3) is a diagram
showing a principle of driving actuators.
[0084] When drive pulses with a serrated wave having a gentle rise
110 and steep fall portion 112 as shown in FIG. 7(a) are impressed
on piezoelectric elements 57 and 55, each of the piezoelectric
elements 57 and 55 extends slowly for displacement in the direction
of its thickness on the gentle rise portion 110 of the drive pulse
as shown in FIG. 7(b2), and each of vibration transmission rods 28
and 47 fixed on piezoelectric elements shows slow displacement in
the axial direction. In this case, stage 12 and stage 13 combined
frictionally respectively with vibration transmission rods 28 and
47 are moved together with the vibration transmission rods 28 and
47 by friction force.
[0085] On the other hand, in the steep fall portion 112 of drive
pulses, piezoelectric elements 57 and 55 shrink rapidly to be
displaced in the direction of its thickness, and vibration
transmission rods 28 and 47 combined respectively with the
piezoelectric elements 57 and 55 also are displaced rapidly in the
axial direction. In this case, stages 12 and 13 combined
frictionally respectively with vibration transmission rods 28 and
47 stay at their positions substantially and do not move, with
their inertial forces overcoming the frictional binding forces. As
a result, the stages move to the position that is on the right side
of what is shown in the initial state shown in FIG. 7(b1). By
impressing drive pulses having a serrated wave of this kind on the
piezoelectric elements 57 and 55, it is possible to move stages 12
and 13 continuously in the axial direction.
[0086] Meanwhile, when the stages 12 and 13 need to be moved
leftward, this can be attained by actions opposite to the foregoing
when impressing drive pulses composed of rapid rise and gentle fall
by changing a serrated waveform to be impressed on the
piezoelectric elements 57 and 55. Incidentally, a rectangular wave
and other waveforms can also be applied for the drive pulses.
[0087] When drive pulses are impressed on piezoelectric element 57
of the first actuator held by the base member, the piezoelectric
element 57 repeats expansion and contraction. The expansion and
contraction of the piezoelectric element 57 are transmitted to
weight 30 and vibration transmission rod 28. Due to a difference of
inertial mass between the weight 30 and the vibration transmission
rod 28, the weight 30 hardly moves, and the expansion and
contraction are transmitted only to the vibration transmission rod
28.
[0088] When the first stage 13 moves in the direction of X-axis,
the second stage 12 connected to the first stage also moves
simultaneously in the direction of X-axis. Owing to pressure spring
55 hooked between the first stage 13 and base member 11 and to
rigid spheres 43 located between the second stage 12 and the base
member 11, the second stage 12 moves smoothly in the direction of
an optical axis with less resistance. In this case, a folded or
bent angle of slack portion 67t where the flexible printed board
turns back is changed, and thereby, flexible printed board 67
connecting the first board 17 and the second board 18 absorbs a
movement of the first stage 13.
[0089] On the other hand, when drive pulses are impressed on
piezoelectric element 58 of the second actuator 44 held by the
second stage 12, the piezoelectric element 58 repeats expansion and
contraction as in the foregoing. The expansion and contraction of
the piezoelectric element 58 are transmitted to weight 46 and
vibration transmission rod 47. Due to a difference of inertial mass
between the weight 46 and the vibration transmission rod 47, the
weight 46 hardly moves, and the expansion and contraction are
transmitted only to the vibration transmission rod 47. Though the
vibration transmission rod 47 is glued on rod supporting arm 45 of
the second stage 12, the expansion and contraction are not
disturbed because adhesives transform elastically. As in the
foregoing, a speed difference of the rod between movements from
side to side causes the second stage 12 to move in the extended
direction of the vibration transmission rod 47 (Y-axis direction),
independently of the first stage 13.
[0090] When drive pulses are impressed on the second actuator 44 as
stated above, the second stage 12 only moves (self-propels) in the
direction of Y-axis independently from the first stage 13. Owing to
pressure spring 55 hooked between the first stage 13 and base
member 11 and to rigid spheres 43 located between the second stage
12 and the first stage, the second stage 12 moves smoothly in the
direction of an optical axis with less resistance. In this case,
slack portion 67t folded at folding section F is twisted, and
flexible printed board 67 connecting the first board 17 and the
second board 18 absorbs a movement of the second stage.
[0091] In the meantime, though the explanation has been given by
using an example wherein slack portion 67t folded to be a U-shape
is formed in the illustration, the folding section F may also be
one that is given a folding line and is in a V-shape.
[0092] Next, a detailed explanation will be given for bendable
flexible printed board 67 having an end portion on one side
connected to the first board 17, and an end portion on the other
side connected to the second board 18 with slack (corresponding to
slack portion 67t in the present example) providing movability to
the image pickup element 15 and the first board 17. Namely, the
image pickup element 15 and the first board 17 correspond to moving
body (movable section), and the second board 18 corresponds to a
fixed body.
[0093] Each of FIGS. 8(a) to 8(c) is a development elevation
showing an example of a flexible printed board 67 shown in FIG.
4.
[0094] FIG. 8(a) shows an example including closed-slits formed
along slack at a slack portion. On the flexible printed board 67
shown in FIG. 8(a), connecting portions 67s for connection with the
first board 17 and that for connection with the second board 18 are
formed on both ends, and plural circuit patterns (wirings) 67c are
formed to connect between connecting portions 67s on opposite
sides. Further, plural closed-slits 100 are formed between each
circuit pattern (wiring) 67c starting from folding section F
(illustrated with broken lines) to both sides of the folding
section F. In this case, the end portion on the other side is
connected with the second board 18 with slack (corresponding to
slack portion 67t in the present example) providing movability to
both image pickup element 15 and the first board 17 have a movable,
whereby, it means that the plural slits 100 are formed along the
slack.
[0095] FIG. 8(b) shows another example including open-slits formed
along slack at a slack section. On the flexible printed board 67
shown in FIG. 8(b), plural open-slits 100 are formed from folding
portion F (illustrated with broken lines) to both sides of the
folding portion F along slack.
[0096] FIG. 8(c) shows another example including open-slits are
formed along a slack at a slack portion. On the flexible printed
board 67 shown in FIG. 8(c), plural open-slits 100 are formed from
folding portion F (illustrated with broken lines) to both sides of
the folding portion F along slack, and a width of the portion where
the open-slits 100 are formed is broader than that of the flexible
printed board 67 shown in FIG. 8(b). By doing this, it is possible
to realize flexible printed board 67 which has less waste and has
an excellent area efficiency for the area needed for an
unillustrated circuit pattern.
[0097] In the specification, "slit" may be formed so that two edge
portions facing each other formed by cutting a part of flexible
printed board 67 do not touch each other, namely, the two edge
portions form a gap between them, as shown in FIGS. 8(h) and 8(c).
"Slit" may also be formed so that the two edge portions touch each
other as shown in FIG. 8(a).
[0098] The slit may extend to form a straight line, S-shaped curve,
and V-shaped line.
[0099] In the specification, "along slack" means the direction from
any one point on one of connecting portion 67s to any one point on
the opposite connecting portion 67s, and may be parallel or provide
angle to the line extends between center points of respective
connecting portions 67s on the flexible printed board.
[0100] Further, both of closed-slits shown in FIG. 8(a) or
open-slits shown in FIGS. 8(b) and 8(c) is formed on the slack
portion, reduces load resistance caused by movement of the first
board in the direction for the flexible printed board 67 to be
twisted, however, open-slit is preferable to form a slit. The
reason for the foregoing is as follows; when strips produced by
forming closed-slits are twisted, load is generated by contact
between respective strips, while, in the case of open-slits, no
contact between respective strips is generated because of air
gaps.
[0101] FIG. 9 is a perspective view for the first board 17, the
second board 18 and the flexible printed board 67.
[0102] As shown in FIG. 9, when the first board 17 housing therein
image pickup element 15 moves in the direction of arrow H, a
bending angle of slack portion 67t of the flexible printed board 67
changes to absorb changes in positional relationship caused by the
movement of the first board 17. Further, when the first board 17
moves in the direction of arrow K, each of strips separated by
closed-slits or open-slits is twisted to absorb changes in
positional relationship caused by the movement of the second board
18.
[0103] FIGS. 10(a) to 10(c) are diagrams showing another example of
the flexible printed board 67. FIGS. 10(a) to 10(c) are diagrams
showing examples of various types of a folding and bending angles
of the slack portion where the printed board is bent.
[0104] FIG. 10(a) shows an example that the flexible printed board
turns back on slack portion 67t with a bent angle of about
180.degree. under the condition that an angle of 0.degree.
represents the state of a plane, and closed-slits or open-slits 100
are formed on the slack portion 67t.
[0105] FIG. 10(b) shows an example that the flexible printed board
turns on slack portion 67t with a bent angle of about 90.degree.,
and closed-slits or open-slits 100 are formed on the slack portion
67t. FIG. 10(c) shows an example that the flexible printed board
turns on slack portion 67t with a bent angle that is less than
90.degree., and closed-slits or open-slits 100 are formed on the
slack portion 67t.
[0106] When any one of the examples shown in FIGS. 10(a) to 10(c)
is applied appropriately corresponding to the total working stroke
of the first board 17 especially in the direction of arrow K and to
the positional relationship between the first board 17 and the
second board representing a fixed body, it is possible to reduce
load resistance that is produced by the flexible printed board 67
when the first board 17 moves in the direction of arrow K.
[0107] The bending or folding angle that is about 90.degree. or
more as in FIGS. 10(a) and 10(b) is more preferable, and it can
reduce efficiently the load resistance that is caused when the
first board 17 moves in the direction (direction of illustration K)
of twisting for the flexible printed board 67. For reducing the
load resistance efficiently while loading in a camera under the
excellent volumetric efficiency, it is preferable that the flexible
printed board is arranged to turn back with an angle of about
180.degree. as shown in FIG. 10(a).
[0108] Incidentally, flexible printed board 67 may turn back plural
times to make the slack portion in W-shaped form.
[0109] Each of FIGS. 16, 17(a) to 17(d) is a diagram showing
another examples of the flexible printed board 67. FIG. 16 is a
perspective view of flexible printed board 67 having the slack
portion formed in W-shape. FIG. 17(a) is an expansion plan of the
flexible printed board 67 shown in FIG. 16, and each of FIGS.
17(b)-17(d) is a side view showing bent shape of the flexible
printed board 67. As shown in FIG. 17(a), by folding positions A,
C, E in mountain fold shape and folding position C and E in valley
fold shape which is folded in opposite direction to the mountain
fold, flexile printed board having a slack portion folded in
W-shape is formed as shown in FIGS. 16 and 17(b). Herein, numeral L
in FIG. 17 represents a length of folded portion of flexible
printed board 67.
[0110] By forming the flexible printed board formed in W-shape, the
positional relationship between flexible printed board 67 and the
second board as a fixed body changes as shown in FIGS. 17(c) and
17(d) when the first board. 17 moves in a direction of arrow H1 and
arrow H2, respectively.
[0111] It shows that the flexible printed board 67 having a slack
portion formed in W-shape reduces load resistance when the first
board 17 moves in the direction of arrow H, and further reduce the
length L of the folded portion.
[0112] FIGS. 11(a) and 11(b) are diagrams showing another examples
of image pickup apparatus 10 to which the bendable printed board
according to the present embodiment is applied. FIG. 11(a) shows a
longitudinal sectional view and FIG. 11(b) is a schematic outline
drawing that is viewed from the front side. In the diagrams, an
image pickup optical system has therein a reflective surface, and a
bendable printed board according to the present embodiment is
applied to the image pickup optical system whose optical axis is
bent.
[0113] As shown in FIG. 11(a), a light flux coming from a
photographic subject passes through lens 101, and after that,
optical axis OA of the light flux is bent by about 90.degree. on
reflective mirror 103 on which a reflective surface is formed.
Then, the light flux from the subject passes through optical block
104 including plural lens groups wherein a prescribed lens group is
movable in the direction of optical axis OB extending in the rear
side of its bent position and through low pass filter 65, to form
an image on an imaging surface of imaging sensor 15. On the back of
the image pickup element 15, there is arranged drive unit 105 for
correcting the camera shake explained earlier. Owing to this, the
image pickup element 15 and the first board 17 connected
electrically with the image pickup element 15 are solidly movable
on the surface perpendicular to the optical axis extending in the
rear side of its bent position.
[0114] FIGS. 18(a) and 18(b) are diagrams showing another examples
of image pickup apparatus 10 to which the bendable printed board
according to the present embodiment is applied. FIG. 18(a) shows an
expansion plan of flexible printed board 67 including slits 100
extending in V shape. FIG. 18(b) shows a longitudinal sectional
view of a part of image pickup apparatus 10 applying the printed
board thereto and a side view of the folded flexible printed board
67.
[0115] Flexible printed board 67 is folded in valley fold shape
along position A and position C and folded in mountain fold shape
along position B and arranged in image pickup apparatus 10 as shown
in the longitudinal sectional view in FIG. 17(b). FIG. 18(b) shows
length L of the folded portion of flexible printed board 67.
[0116] As shown in FIG. 18(a), slits 100 are formed on slack
portion 67t extending to form V-shape. Herein, each slit 100 is
formed between plural printed wirings along the slack.
[0117] Since slit 100 extends in V-shape, slit 100 is formed with
angle .theta. between the perpendicular direction to the folded
positions A, B and C. Therefore, it shortens line L of the folded
portion.
[0118] Bendable printed board 67 according to the present
embodiment is provided with end portion on one side of the printed
board 67 connected to the first board 17, turns back at a folding
angle of about 180.degree. with slack portion 67t, and is provided
with slits 100 formed on the slack portion 67t. An end portion on
the other side is drawn out of the image pickup apparatus 10 to be
connected to an image processing circuit housed in an unillustrated
camera main body.
Example
[0119] There will be explained, as follows, an example of the
flexible printed board relating to the invention on which slit are
formed on a slack portion along the slack.
[0120] Each of FIGS. 12(a) to 12(c) is a diagram showing a form of
the flexible printed board which was used as a test sample. FIG.
12(a) is a side view showing a folded form of the flexible printed
board, FIG. 12(b) is an expansion plan of the flexible printed
board on which two open-slits are formed, and FIG. 12(c) is a
expansion view of the flexible printed board on which three
open-slits are formed.
[0121] Six types of flexible printed boards each being folded to be
in a form of a side view shown in FIG. 12(a) and having an outer
shape of a rectangle and the total width of 10 mm, were-used as
samples.
[0122] The sample on which two slits are formed is one on which two
open-slits each having a width of 1.4 mm are formed as shown in
FIG. 12(b), and pattern sections each being in a form of a 2.4 mm
strip are formed on both sides of the open-slits. The sample on
which three open-slits are formed is one on which three open-slits
each having a width of 0.93 mm are formed as shown in FIG. 12(c),
and pattern sections each being in a form of a 1.8 mm strip are
formed on both sides of the open-slits.
[0123] With respect to the other samples, a sample on which one
slit is formed is one on which a slit with a width of 2.8 mm is
formed on the center of the total width of 10 mm, a sample on which
four slits are formed is one with the total width of 10 mm on which
four slits each having a width of 0.7 mm are formed, and pattern
sections each being in a form of a 1.44 mm strip are formed on both
sides of the slits, and a sample on which five slits are formed is
one with the total width of 10 mm on which five slits each having a
width of 0.56 mm are formed, and pattern sections each being in a
form of a 1.2 mm strip are formed on both sides of the slits.
[0124] As a comparative example, there was used a flexible printed
board with a total width of 10 mm that is folded to be in a form of
a side view shown in FIG. 12(a) and has no slit formed thereon.
[0125] FIG. 13 is a perspective view showing an outer shape of a
flexible printed board folded to be in a form of a side view shown
in FIG. 12(a). FIG. 13 shows a perspective view of a sample on
which three slits are formed.
[0126] FIG. 14 is a diagram showing measurement conditions. In the
measurement conditions, two flat parts 67f after valley fold are
made to be in the state where the two flat parts are deviated each
other by 1 mm relatively on the same plane, and restoring force of
these two flat parts 67f to return to their original state was
measured.
[0127] Under the aforesaid measurement conditions, each restoring
force was measured for flexible printed boards each having slits in
quantity of its own number including the comparative example having
no slit formed thereon, as one having slit in quantity of zero.
[0128] FIG. 15 shows a graph including measurement results of
restoring forces obtained under the aforesaid measurement
conditions.
[0129] FIG. 15 shows that, when the total including the total width
and the sum total of widths of slits is the same to the sum total
of widths of pattern sections, forming slits reduce restoring
force, and increasing the number of slits reduces the restoring
force for twisting of the flexible printed board greatly.
[0130] This restoring force is provided resulting in the load
resistance when the first board 17 shown in FIG. 9 moves in the
direction of arrow K, and closed-slits or open-slits formed on a
slack portion along slack reduce the load resistance.
[0131] For reducing the load resistance, it is equally preferable
that a thickness of the slack portion is within a range of 0.02 mm
to 0.2 mm. In this case, it is also possible to make only the
portion where slits are formed in the slack portion to be thin
partially to form to be in the aforesaid thickness, by a method
such as an etching method.
[0132] For reducing the load resistance further, it is preferable
that circuit pattern (wiring) 67c is formed only one side of
flexible printed board 67, in at least a portion where slits on the
slack portion are formed.
[0133] As explained above, by forming closed-slits or open-slits on
the slack portion of the printed board in the direction of slack,
in the image device which has an image pickup element and a
bendable printed board whose end portion on one side is connected
to a movable portion having the aforesaid image pickup element for
inputting and outputting of information with the image pickup
element, and an end portion on the other side is connected to a
fixed portion in the state having slack, and moves the image pickup
element in the optional direction in a plane perpendicular to an
optical axis of the imaging optical system, it is possible to
reduce load resistance that is caused by the printed board when the
image pickup element moves. Owing to this, an actuator having a
driving power that is smaller than that of a conventional actuator
can be used, which can realize downsizing and power saving for the
image pickup apparatus equipped with a camera shake correcting
function.
[0134] Though the fixed body corresponds to the second board 18 of
the image device in the present embodiment, it is also possible to
make other members constituted integrally with the image pickup
apparatus to be fixed bodies. Further, though the end portion on
the other side is connected to the image pickup element through the
first board 17, the end portion on one side may also be connected
directly to the image pickup element. For example, one of the end
portions may be directly connected to the image pickup element. In
that case, the image pickup element corresponds to the movable
portion.
[0135] Further, when an actuator that is the same as a conventional
one is used, it is possible to reduce an amount of slack of the
bendable printed board which has been secured, and an area of the
bendable printed board can be small. Owing to this, a space needed
for housing therein the bendable printed board can be small, which
can realize downsizing and low cost of the image pickup apparatus
equipped with a camera shake correcting function.
[0136] Meanwhile, an explanation has been given by the use of an
example wherein the bendable printed board according to the
invention is applied to the image pickup apparatus conducting a
camera shake correction by moving the image pickup element on the
predefined plane. However, it the scope of the invention is not
limited to the example, and the bendable printed board according to
the invention may naturally be applied to any embodiment whose end
portion on one side is connected to a moving body movable in an
arbitral direction on a prescribed plane, and an end portion on the
other side is connected to a fixed body with slack providing
movability to the moving body.
* * * * *