JP2007019813A - Fixing structure of imaging device, lens unit, and image pickup device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure for precisely fixing an imaging device to a lens barrel with a simple constitution and to provide a low-cost, high-precision and small-sized lens unit and an image pickup device. <P>SOLUTION: With respect to the structure for fixing an imaging device 17 to a lens barrel 8 together with a wiring board 18 wired on the imaging device and a heat dissipating member 19 dissipating heat of the imaging device, the lens barrel is provided with a contact part 34 to be brought into contact with the imaging device in a direction of an optical axis, and at least one of the lens barrel and the heat dissipating member is provided with positioning means 26 and 27 for positioning the heat dissipating member to the lens barrel in a direction orthogonal to the optical axis, and the wiring board and the imaging device are positioned and fixed to the heat dissipating member, and the heat dissipating member having the imaging device and the wiring board fixed thereto is positioned by the positioning means, and a pressing member 20 having pressing parts 30 and 31 capable of pressing the heat dissipating member to the lens barrel by an elastic force and fixing parts 22 and 25 capable of fixing the heat dissipating member to the lens barrel has the pressing parts elastically deformed so as to press the heat dissipating member to the lens barrel and is fixed to the lens barrel. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fixing structure of an image sensor with respect to a lens barrel, a lens unit in which the image sensor is fixed to the lens barrel, and an imaging device.

  When the imaging element is fitted and fixed to the lens barrel, there is a problem that the imaging element cannot be accurately positioned in a direction perpendicular to the optical axis because of the dimensional accuracy of the imaging element.

Patent Document 1 describes a structure in which an image sensor is fixed to a spacer that fits into a recess of a lens barrel, and the image sensor is pressed by a leaf spring so as to press the spacer against the recess.
JP 2004-15427 A

  In the structure of Patent Document 1, the imaging element has a special shape, which increases costs, and at the same time, requires high positioning accuracy in the optical axis direction and the direction perpendicular to the optical axis, and it is difficult to achieve satisfactory accuracy in both directions. There's a problem.

  In view of the above problems, the present invention provides a structure for accurately fixing an image sensor to a lens barrel with a simple configuration, and a small, particularly thin, highly accurate and inexpensive lens unit and It is an object to provide an imaging device.

  In order to solve the above problems, according to the present invention, a structure in which an image pickup device is fixed to a lens barrel together with a wiring board that is wired to the image pickup device and a heat dissipation member that dissipates heat of the image pickup device, An abutting portion that abuts the imaging element in the optical axis direction is provided on the barrel, and the heat radiating member is positioned in a direction perpendicular to the optical axis with respect to the barrel on at least one of the lens barrel and the heat radiating member. Positioning means for positioning, positioning and fixing the wiring board and the imaging element with respect to the heat radiating member, and fixing the imaging member and the wiring board to the lens barrel by the positioning means. The pressing member includes a pressing part that can press the heat radiating member toward the lens barrel by an elastic force, and a fixing part that can be fixed to the lens barrel. It said pressing portion is elastically deformed wood so as to press toward the barrel, to position the fixing member in the optical axis direction by fixing the lens barrel.

  According to this structure, since the imaging element is positioned in the direction perpendicular to the optical axis by the heat radiating member, the imaging element can be accurately positioned without increasing the number of components.

  In the image sensor fixing structure of the present invention, the pressing member may include the two fixing portions and the pressing portion on a line connecting the two fixing portions. As a result, since the fulcrum for fixing the pressing member to the lens barrel and the action point for the imaging element are arranged in a straight line, a force in the torsional direction does not act on the pressing member and it is stable.

  In the image sensor fixing structure according to the present invention, the pressing portion may be a leaf spring extending on a line connecting the two fixing portions. Thereby, the pressing member can be formed integrally with the pressing portion.

  In the imaging device fixing structure of the present invention, the fixing portion may be provided at a position where a distance traversing the imaging device becomes long. Thereby, the distance between the fulcrum which supports a pressing member becomes long, and a pressing member is stabilized.

  In the imaging element fixing structure of the present invention, the positioning means may further position the pressing member in a direction perpendicular to the optical axis. Thereby, the position where the pressing member presses the heat radiating member becomes constant, and the position of the force acting on the imaging element does not change.

  In the imaging element fixing structure of the present invention, the positioning means includes a positioning pin protruding from the lens barrel in the optical axis direction, and a pin hole provided in the heat dissipation member and engaged with the positioning pin. May be. Thereby, the heat radiating member can be positioned on the lens barrel with a simple structure.

  In addition, the lens unit having the imaging element fixing structure can be provided at a low cost while being small and highly accurate. As a result, it is possible to reduce the size and thickness of the fixing portion of the image sensor, and to provide a thin unit.

  The lens unit of the present invention can constitute a bending optical system having an optical member that bends the optical axis by about 90 °.

  The imaging device according to the present invention includes the lens unit. Thereby, a highly accurate and inexpensive image sensor can be provided.

  As described above, according to the present invention, the imaging element is positioned with respect to the lens barrel by positioning the imaging element with respect to the heat dissipation member and positioning the heat dissipation member with respect to the lens barrel. This makes it possible to position the image pickup device with a small size and high accuracy without increasing the number of components.

Embodiments of the present invention will now be described with reference to the drawings.
FIG. 1 shows a digital camera (imaging device) 1 according to a first embodiment of the present invention. The digital camera 1 is provided with a flash 3, a finder 4, and a lens opening 5 on the front surface of a main body 2, and a lens unit 6 is provided inside the main body 2 so that a subject can be seen from the lens opening 5.

  FIG. 2 is a longitudinal section of the lens unit 6 portion of the digital camera 1. The lens unit 6 constitutes a bending optical system that bends the optical axis x of light incident from the subject by 90 °, and includes a front lens barrel 7 on the subject side (upper side) and an imaging surface side (lower side) in the optical axis x direction. The rear lens barrel 8 is fixed integrally.

  In the front lens barrel 7, a first lens group 9 including an optical member that bends light incident from a subject by 90 °, and a second lens group 10 that is a variable power lens movable up and down along the optical axis x, Is provided. A shutter unit 11 is fixed together with an elastic body 12 in a gap provided at a joint portion between the front lens barrel 7 and the rear lens barrel 8.

  A third lens group 13 into which light that has passed through the shutter unit 11 is incident inside the rear lens barrel 8, a fourth lens group 14 that is movable in the optical axis x direction inside the rear lens barrel 8, Further, on the lower side, the fifth lens group 15, a low-pass filter 16 that blocks high-frequency components of light that has passed through the fifth lens group 15, and an imaging element 17 that has an imaging surface on which light that has passed through the low-pass filter 16 forms an image. And are provided. The imaging device 17 is a CCD that converts an image formed on the imaging surface into an electrical signal. The imaging device 17 removes heat from the flexible substrate 18 that is a wiring board to be wired to the imaging device 17 and the imaging device 17, and in the surrounding air. A heat radiating member 19 that is diffused to the rear is bonded and fixed to the lower end of the rear lens barrel 8 by a pressing member 20.

  3 shows the lower end portion of the rear lens barrel 8 in a state where the image pickup device 17 is fixed, and FIG. 4 shows the image pickup device 17, the flexible substrate 18, the heat radiating member 19 and the presser from the lower end portion of the rear lens barrel 8. A mode that the member 20 was decomposed | disassembled is shown. The holding member 20 is made of a metal plate, and is provided on the opposite side of the first fixing portion 22 with respect to the optical axis x, and a first fixing portion 22 that engages with a fixing protrusion 21 provided on the rear lens barrel 8. A second fixing portion 25 fixed by a screw 24 screwed into the screw hole 23 of the rear lens barrel 8, positioning pins (positioning means) 26 and 27 protruding from the rear lens barrel 8 in the optical axis x direction, respectively. It has pin holes 28 and 29 to be engaged, and pressing portions 30 and 31 which are bent so that opposing protruding portions formed by punching the pressing member 20 into an H shape project obliquely toward the heat radiating member 19 side. The pressing parts 30 and 31 have elasticity and function as leaf springs. The heat dissipating member 19 has pin holes 32 and 33 that engage with the positioning pins 26 and 27, respectively. The rear lens barrel 8 further includes three contact portions 34 (only two are shown in FIG. 4) that contact the image sensor 17.

  FIG. 5 shows the positional relationship between the image sensor 17, the heat radiating member 19, and the pressing member 20. The first fixing portion 22 and the second fixing portion 25 are provided at substantially diagonal positions of the image sensor 17 and have a long distance across the image sensor 17. Further, the pressing portions 30 and 31 of the pressing member 20 are all lines connecting the first fixing portion 22 and the second fixing portion 25 with the opposing free ends 30a and 31a and the fixed ends 30b and 31b serving as the base points of elastic deformation. It is lined up on q.

  Furthermore, FIG. 6 shows an AA cross section of FIG. The image sensor 17 is pressed against the contact portion 34 of the rear lens barrel 8 by the pressing member 20 through the flexible substrate 18 and the heat radiating member 19. The contact portion 34 holds the surface of the image sensor 17 at a predetermined position in the optical axis x direction and at a right angle to the optical axis x. As shown in FIG. 5, the pressing portions 30 and 31 press the substantially center of gravity of a triangle having the three contact portions 34 as apexes toward the rear lens barrel 8.

Next, a procedure for fixing the image sensor 17 having the above configuration will be described.
First, the image sensor 17 and the flexible substrate 18 are fixed so that the circuit is appropriately connected. The terminal configuration of the image sensor 17 is called flat non-lead or end plating. There is no general lead wire, and a flexible board having a width close to the width of the image sensor 17 can be connected and fixed. Then, the position of the image sensor 17 in the plane perpendicular to the optical axis x with respect to the heat radiating member 19 (relative to the pin holes 32 and 33) is accurately determined by a jig (not shown). The flexible substrate 18 is bonded and fixed to the heat radiating member 19. When the image sensor 17 is fixed, the pin holes 32 and 33 of the heat radiating member 19 are fitted to the positioning pins 26 and 27 of the rear lens barrel 8. Then, the first fixing portion 22 of the pressing member 20 is engaged with the fixing protrusion 21 of the rear lens barrel 8, and the pin holes 28 and 29 are engaged with the positioning pins 26 and 27, respectively. At this time, the pressing portions 30 and 31 come into contact with the heat radiating member 19, and the second fixing portion 25 is lifted from the rear lens barrel 8. Further, the screw 24 is screwed into the screw hole 23 through the second fixing portion. By tightening the screw 23, the pressing portions 30 and 31 are elastically deformed and retracted, and the second fixing portion 25 can be brought into close contact with the rear lens barrel 8 as shown in FIG.

Further, the operation of the structure for fixing the image sensor 17 will be described.
In a state where the screw 24 is tightened, the pressing portions 31 and 32 press the imaging element 17 against the contact portion 34 of the rear lens barrel 8 through the heat radiating member 19 and the flexible substrate 18. This ensures the positioning of the image sensor 17 in the optical axis x direction by the contact portion 34. The imaging element 17 is positioned in a direction perpendicular to the optical axis x with respect to the heat radiating member 19, and the heat radiating member 19 is positioned in a direction perpendicular to the optical axis x by the positioning pins 26 and 27. Thereby, the image sensor 17 is accurately positioned in the direction perpendicular to the optical axis x with respect to the rear lens barrel 8.

  As shown in FIG. 5, since the pressing portions 30 and 31 are provided on the line q connecting the first fixing portion 22 and the second fixing portion 25, a reaction for pressing the heat radiating member 19 is applied on the line q. That is, this reaction does not act as a force in the torsional direction on the line q, but is received as a force in the optical axis x direction by the first fixing portion 22 and the second fixing portion 25. In addition, since the pressing member 20 is provided so that the distance across the imaging element 17 is longer between the first fixing portion 22 and the second fixing portion 25, the positions where the reaction of the pressing portions 30, 31 are shifted. However, the force in the twisting direction can be relatively reduced. In addition, since the pressing member 20 has a long distance between the first fixing portion 22 and the second fixing portion 25, the length of the pressing portions 30 and 31 can be increased, and the pressing portions 30 and 31 have sufficient elasticity. Can be given.

  Further, by combining the terminal configuration of the image sensor 17 described above, the bending type optical system, and the fixing structure of the present invention, the entire lens unit 6 can be reduced in thickness, and the thin camera 1 is provided. Is possible.

  In this embodiment, the imaging element 17, the flexible substrate 18, the heat radiating member 19, and the pressing member 20 are arranged in this order. However, the present invention is not limited to this, and the imaging element 17, the heat radiating member 19, the flexible substrate 18, and the pressing member 20 You may arrange in order.

1 is a front view of a digital camera according to a first embodiment of the present invention. Sectional drawing in the optical axis of the digital camera of FIG. The perspective view of the lens barrel lower end part of the digital camera of FIG. FIG. 4 is an exploded perspective view of a lower end portion of the lens barrel in FIG. 3. FIG. 4 is a bottom view showing the positional relationship between the image sensor and the pressing member in FIG. 3. FIG. 6 is a cross-sectional view taken along the line AA in FIG. 5.

Explanation of symbols

1 Digital camera (imaging device)
6 Lens unit 8 Rear lens barrel 17 Image sensor 18 Flexible substrate (wiring substrate)
19 heat radiating member 20 holding member 22 first fixing portion 25 second fixing portion 26, 27 positioning pin (positioning means)
30, 31 Press part 32, 33 Pin hole 34 Contact part

Claims (9)

The image sensor is a structure that is fixed to a lens barrel together with a wiring board that is wired to the image sensor and a heat dissipation member that dissipates heat of the image sensor,
The lens barrel is provided with a contact portion that contacts the image sensor in the optical axis direction,
Positioning means for positioning the heat dissipation member in a direction perpendicular to the optical axis with respect to the lens barrel is provided in at least one of the lens barrel and the heat dissipation member,
Positioning and fixing the wiring board and the image sensor with respect to the heat dissipation member,
The heat radiating member that fixes the imaging element and the wiring board is positioned with respect to the lens barrel by the positioning means,
A pressing member having a pressing part capable of pressing the heat radiating member toward the lens barrel by an elastic force and a fixing part fixed to the lens barrel, the pressing part using the heat radiating member as the lens barrel An image sensor fixing structure, wherein the pressing portion is elastically deformed so as to be pressed toward the lens barrel and positioned by fixing the fixing member to the lens barrel in the optical axis direction.   The imaging element fixing structure according to claim 1, wherein the pressing member includes two fixing parts, and the pressing part is provided on a line connecting the two fixing parts.   The imaging element fixing structure according to claim 2, wherein the pressing portion is a leaf spring extending on a line connecting the two fixing portions.   The imaging device fixing structure according to claim 1, wherein the fixing portion is provided at a position where a distance across the imaging device becomes long.   The imaging device fixing structure according to claim 1, wherein the positioning unit further positions the pressing member in a direction perpendicular to the optical axis.   6. The positioning device according to claim 1, wherein the positioning means includes a positioning pin protruding from the lens barrel in the optical axis direction, and a pin hole provided in the heat dissipation member and engaged with the positioning pin. A fixing structure of the imaging device according to claim 1.   6. A lens unit having the imaging element fixing structure according to claim 1.   The lens unit according to claim 7, further comprising an optical member that bends the optical axis by about 90 °.   An image sensor having the lens unit according to claim 7.

Images