JP2011244162A - Camera module and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera module and a camera in which generation of vignetting by a dust-proof member sandwiched between an optical plate material and an image pickup device is suppressed.SOLUTION: The camera module includes: a barrel having a rear wall part with an opening in which a first step part which is connected to the inside and outside and spreads outward with a level difference at the back in the optical axis direction, and a second step part which extends in the direction for surrounding an optical axis near an outer wall from the first step part are formed; an image-formation optical system stored in the barrel; the optical plate material arranged at the first step part; a substrate which is fixed to the outer wall of the rear wall part at a posture that the image pickup device is put into the opening; a cylinder part which is sandwiched between the optical plate material and the image pickup device, pressed by both of the circumference of the optical plate material and the circumference of the image pickup device to make a circuit around the optical axis along the inner wall of the opening; and the dust-proof member with a flange part which makes a part on the side of the optical plate material from the second step part and a part on the image pickup device from the second step part of the cylinder part share deformation of the cylinder part when the cylinder part is pressed by the optical plate member and the image pickup device.

Description

  The present invention relates to a camera module including an imaging optical system, an optical plate member, and an imaging device, and a camera having the camera module.

  2. Description of the Related Art Conventionally, an imaging optical system such as a photographing lens and an optical plate material such as a near-infrared (InfraRed) cut filter and a low-pass filter are provided in a lens barrel in order from the subject side, and a CCD (Charge Coupled) is provided at the rear end. A camera module to which a substrate on which an image pickup device such as Device) is mounted is attached is known.

  In such a camera module, the peripheral edge of the optical plate and the imaging are avoided so as not to allow the passage of subject light so that dust does not enter between the optical plate inside the lens barrel and the image sensor at the rear end of the lens barrel. There is one in which a cylindrical dustproof member is sandwiched between the periphery of the element (for example, see Patent Documents 1, 2, 3, and 4).

  The camera module equipped with a dustproof member does not want to clearly capture the image of the optical plate material, such as adhering to the surface opposite to the surface facing the image sensor, on the image sensor. Some have a certain distance from the image sensor.

  In a camera module in which the distance between the optical plate and the image sensor is somewhat long, the dust-proof member sandwiched between the optical plate and the image sensor's peripheral edge, which avoids the subject light passage range, is easily bent and dust-proof. There is a problem that so-called vignetting occurs due to the middle part of the member entering the passage range of the subject light.

JP 2002-300441 A JP 2004-53769 A Japanese Patent Laid-Open No. 2006-100088 JP 2008-205911 A

  An object of the present invention is to provide a camera module and a camera in which occurrence of vignetting is suppressed by a dustproof member sandwiched between an optical plate material and an image sensor.

The camera module of the present invention
An imaging optical system;
A first step portion having an internal space for accommodating the imaging optical system, extending inward and outward in the optical axis direction on the imaging plane side, and having a step toward the outside; A lens barrel provided with a rear wall portion having an opening formed with a second step portion extending in a direction surrounding the optical axis closer to the outer wall than the step portion;
An optical plate disposed on the first step, and
An image sensor is mounted, and in a posture in which the image sensor is inserted into the opening, a substrate fixed to the outer wall of the rear wall,
A cylindrical portion sandwiched between the optical plate material and the imaging element and pushed by both the optical plate material peripheral edge and the imaging element peripheral edge to make a round around the optical axis along the inner wall of the opening, and from the cylindrical part The deformation of the cylindrical portion when it extends and enters the second step portion and the cylindrical portion is pushed by the optical plate material and the imaging element is made from the second step portion of the cylindrical portion. And a dust-proof member having a collar portion that is divided into a portion that extends toward the optical plate and a portion that extends toward the imaging element rather than the second step portion.

  In the camera module of the present invention, the deformation of the cylindrical portion when the cylindrical portion is pushed by the optical member peripheral edge and the imaging element peripheral edge causes the flange portion to enter the second step portion, so that the second step portion is more than the second step portion. Since the portion that extends to the optical plate material side and the portion that extends to the imaging element side rather than the second step portion are shared, the deformation does not bias to either one. Thereby, in the camera module of the present invention, the occurrence of vignetting is suppressed.

Here, in the camera module of the present invention,
The second step portion is a step portion that goes around the optical axis around the inner wall of the opening,
It is preferable that the said collar part is an annular collar part extended from the said cylinder part, surrounding this cylinder part over the circumference and having entered into the said 2nd step part.

  Thereby, in the camera module of this invention, generation | occurrence | production of vignetting is suppressed reliably.

In the camera module of the present invention,
The optical plate material may be an infrared cut filter.

Here, in the camera module of the present invention,
The dustproof member is preferably a member made of rubber.

  By doing in this way, high dustproof property is securable at low cost.

In the camera module of the present invention,
It is also a preferable aspect that the imaging optical system has a prism and is a bending optical system that reflects incident light from the subject side by the prism and guides it to the imaging device.

  Since the optical path length that tends to be shortened by thinning can be secured, it contributes to ensuring both functionality and thinning.

The camera of the present invention
The camera module according to any one of claims 1 to 5,
And a camera body incorporating the camera module.

  As a result, the optical path length that tends to be shortened due to the thinning can be secured, so that both the ensuring of functionality and the thinning can be achieved.

  According to the camera module and the camera of the present invention, vignetting due to the dust-proof member sandwiched between the optical plate material and the imaging element is suppressed.

It is the perspective view which showed the internal structure of the camera module. It is a figure which shows the state which looked at the camera module shown in FIG. 1 from the optical axis direction back. It is Q-Q 'sectional drawing shown in FIG. It is an external appearance perspective view of a camera module in the state where a substrate was removed from a back wall part. It is an expanded sectional view of the conventional dustproof rubber. It is sectional drawing of the dustproof rubber of this embodiment. It is a perspective view which shows the camera incorporating the camera module shown in FIG.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a perspective view showing the internal structure of the camera module.

  The camera module 10 employs a bending optical system, reflects the light beam taken into the lens barrel 11 by the objective lens 12 by the prism 13, and further, the first variable power lens 14, the focus lens 15, and the second lens. The light passes through the variable magnification lens 16 and enters a CCD image pickup device 17 disposed in an opening (not shown) communicating with the internal space 111 of the lens barrel 11 and the outside. The CCD image pickup device 17 is mounted on a substrate 18, and the CCD image pickup device 17 is disposed in an opening through which the internal space 111 is viewed. So that it is screwed. A signal transmission flexible substrate 20 extends from the CCD image sensor 17 on the substrate 18. This camera module 10 is an embodiment of the camera module of the present invention.

  The focus lens 15 is held by the focus lens frame 21. The focus lens frame 21 is supported by two guide shafts 22 extending in the optical axis direction so as to be movable in the optical axis direction. When the focus motor 23 rotates, the focus lens frame 21 has two guides. It moves in the optical axis direction while being guided by the shaft 22. Thus, a focused subject image is formed on the CCD image sensor even if the subject distance is different.

  The first and second variable power lenses 14 and 16 are held by first and second variable power lens frames 24 and 25, respectively. The first and second variable power lens frames 24 and 25 are supported by two guide shafts 26 (only one is shown here) extending in the optical axis direction so as to be movable in the optical axis direction. Yes. When the zooming motor 27 rotates, the rotation is transmitted to the cam rod 29 via the reduction gear 28, and the cam rod 29 rotates. The cam rod 29 has a cam groove 291 for the first variable magnification lens frame 24 and a cam groove 292 for the second variable magnification lens frame 25. The first zoom lens frame 24 has a cam pin (not shown) that enters the cam groove 291, and the second zoom lens frame 25 has a cam pin (not shown) that enters the cam groove 292. Is formed. Accordingly, when the cam rod 29 is rotated by the rotation of the zooming motor 27, the first and second zoom lens frames 24 and 25 are moved in the optical axis direction according to the two cam grooves 291 and 292 formed in the cam rod 29. To do. As a result, the focal length of the imaging optical system is changed.

  The rotation commands to the focusing motor 23 and the magnification changing motor 27 are transmitted to the motors 23 and 27 via the flexible substrate 30.

  Here, in the camera module 10, an IR cut filter for cutting near infrared light is provided between the second variable magnification lens 16 and the CCD image sensor 17. As will be described in detail later, in order to prevent dust and the like from entering the space between the IR cut filter and the CCD image sensor 17 between the IR cut filter and the CCD image sensor 17, the periphery of the IR cut filter A dust-proof rubber sandwiched between both the peripheral portion and the peripheral portion of the CCD image sensor 17 is provided.

  FIG. 2 is a diagram illustrating a state where the camera module illustrated in FIG. 1 is viewed from the rear in the optical axis direction.

  As shown in FIG. 2, the substrate 18 on which the CCD image sensor 17 is mounted is screwed to the outer wall of the rear wall portion 112 of the lens barrel 11 with four screws 19.

  3 is a cross-sectional view taken along the line Q-Q 'shown in FIG.

  FIG. 3 is a cross-sectional view of the rear wall 112 of the lens barrel 11 of the camera module 10. Here, both the peripheral edge of the CCD image sensor 17 and the peripheral edge of the IR cut filter 40 are shown. An abutting dust-proof rubber 1 is shown. The dust-proof rubber 1 includes a first contact portion 1a that contacts the peripheral portion of the CCD image sensor 17, a second contact portion 1b that contacts the peripheral portion of the IR cut filter 40, and the first contact portion. A flange portion 1c that protrudes outward at a position between 1a and the second contact portion 1b is provided.

  FIG. 3 shows a range through which the light beam passes in the lens barrel.

  FIG. 4 is an external perspective view of the camera module with the substrate removed from the rear wall.

  In the camera module 10 shown in FIG. 4, the dust-proof rubber 1 is exposed by removing the substrate 18 on which the CCD image pickup device 17 is mounted from the rear wall portion 112 of the lens barrel 11. The dust-proof rubber 1 includes a first contact portion 1a that contacts the peripheral edge of the CCD image pickup device 17 in a rectangular shape, a flange portion 1c that protrudes outward at a position deeper than the first contact portion 1a, A second abutting portion 1b that abuts on the periphery of the IR cut filter 40 in a rectangular shape at a position deeper than the portion 1c. A combination of the first contact portion 1a and the second contact portion 1b corresponds to an example of the cylindrical portion referred to in the present invention. In FIG. 4, the second variable magnification lens 16 described above is viewed from the back side of the IR cut filter 40.

  FIG. 5 is an enlarged cross-sectional view of a conventional dustproof rubber.

  FIG. 5 shows a conventional dustproof rubber 50 sandwiched between the peripheral edge of the CCD image sensor 17 and the peripheral edge of the IR cut filter 40.

  Part (a) of FIG. 5 shows a state before the substrate 18 is fixed to the outer wall of the rear wall portion 112 of the lens barrel 11, and part (b) of FIG. 5 shows the substrate 18. The state after being fixed to the outer wall of the rear wall portion 112 of the lens barrel 11 is shown.

  The conventional dust-proof rubber 50 includes a first contact portion 50a that contacts the peripheral portion of the CCD image sensor 17 in a rectangular shape, and a second contact portion 50b that contacts the peripheral portion of the IR cut filter 40 in a rectangular shape. It is a cylinder. When the dust-proof rubber 50 is sandwiched between the peripheral edge of the CCD image sensor 17 and the peripheral edge of the IR cut filter 40 and compressed in the vertical direction in FIG. 5, as shown in part (b) of FIG. 5. In the meantime, the middle of the second contact portion 50b is bent to reach the light beam passage range indicated by the oblique lines, and so-called vignetting occurs.

  Therefore, in the camera module 10 of the present embodiment, the occurrence of vignetting is prevented as described below.

  FIG. 6 is a cross-sectional view of the dust-proof rubber of this embodiment.

  As described above, the dust-proof rubber 1 shown in FIG. 6 is placed on the first contact portion 1 a that contacts the peripheral portion of the CCD image sensor 17 and the first step portion 116 provided on the inner peripheral surface of the lens barrel 11. The second abutting portion 1b that abuts on the peripheral portion of the IR cut filter 40, and the flange portion 1c projecting outward from between the first abutting portion 1a and the second abutting portion 1b. Yes. Further, as shown in part (b) of FIG. 6, in a state where the dust-proof rubber 1 is sandwiched between the peripheral portion of the CCD image sensor 17 and the peripheral portion of the IR cut filter 40, the second step portion 117 is The distance L2 to the IR cut filter 40 is longer than the distance L1 to the CCD image sensor 17. The first step portion 116 corresponds to an example of the first step portion referred to in the present invention, and the second step portion 117 corresponds to an example of the second step portion referred to in the present invention.

  Here, regarding the length of the first contact portion 1a and the second contact portion 1b in the optical axis direction, the first contact portion 1a is shorter than the second contact portion 1b. Moreover, the thickness of the 1st contact part 1a is thicker than the thickness of the 2nd contact part 1b. For this reason, the 2nd contact part 1b becomes easier to bend than the 1st contact part 1a, and there exists a possibility that vignetting may generate | occur | produce if the 2nd contact part 1b bends to an end extremely.

  However, in the camera module 10 of this embodiment, the occurrence of vignetting is prevented as described below.

  When the dust-proof rubber 1 of the camera module 10 of this embodiment is sandwiched between the peripheral edge of the CCD image sensor 17 and the peripheral edge of the IR cut filter 40 and begins to be compressed in the vertical direction in FIG. The contact pressure of the edge of the second contact portion 1b against the IR cut filter 40 until the flange portion 1c contacts the second stepped portion 117 provided on the inner peripheral surface, and the first contact portion 1a Both the contact pressure with respect to the CCD image pickup device 17 at the edge slightly increase. Thereby, although the 2nd contact part 1b bends slightly, the 1st contact part 1a whose length of an optical axis direction is shorter and thick than the 2nd contact part 1b does not bend. Thereafter, when the flange 1c comes into contact with the second stepped portion 117, the contact pressure against the IR cut filter 40 at the edge of the second contact portion 1b does not increase, and the second contact portion 1b bends further. There is no. On the other hand, the contact pressure with respect to the CCD image sensor 17 at the edge of the first contact portion 1a continues to increase after the flange portion 1c contacts the second stepped portion 117, and the first contact portion 1a And is in close contact with the peripheral edge of the CCD image sensor 17 in a state of being slightly inclined to the light beam side so as not to enter the light beam passage range. As described above, in the camera module 10 of the present embodiment, the flange portion 1c of the dust-proof rubber 1 abuts against the second stepped portion 117, so that the bending due to compression causes the first abutment portion 1a and the second abutment portion 1b to Therefore, the occurrence of vignetting is prevented.

  FIG. 7 is a perspective view showing a camera incorporating the camera module shown in FIG.

  In the camera 200 shown in FIG. 7, the camera module 10 described above is built in the camera body 211, and the objective lens 12 of the camera module 10 is exposed in the front of the camera body 211. The camera body 211 is provided with a shutter button 212 that causes the camera module 10 to perform a photographing operation when pressed. This camera 200 is an embodiment of the camera of the present invention.

  In the above-described camera module 10 built in the camera 200, the subject luminous flux incident in the arrow X direction shown in FIG. 7 through the objective lens 12 is reflected by the prism 13 in the arrow Y direction shown in FIG. Head to 17. By doing so, the height of the camera 200 is longer than the thickness of the camera 200 as compared with the case where there is no prism 13 and the optical path length can be secured only in the thickness direction of the camera 200 (X direction shown in FIG. 7). The direction (Y direction in FIG. 7) can be used as the optical path length, and the camera function can be enhanced even though the outer dimensions of the camera are the same.

  In the above-described embodiment, a bending optical system that bends the optical path using a prism is used. However, the present invention can also be applied to a camera module that is not a bending optical system.

  In the above-described embodiment, an IR cut filter is shown as an example of the optical plate material according to the present invention. However, the optical plate material according to the present invention may be a low-pass filter.

  In the above-described embodiment, a CCD image pickup device is shown as an example of the image pickup device according to the present invention. However, the image pickup device according to the present invention may be a CMOS (Complementary Metal Oxide Semiconductor).

DESCRIPTION OF SYMBOLS 1, 50 Dust-proof rubber 1a, 50a 1st contact part 1b, 50b 2nd contact part 1c ridge part 10 Camera module 11 Lens barrel 111 Internal space 112 Rear wall part 116 1st step part 117 2nd step part 12 Objective lens DESCRIPTION OF SYMBOLS 13 Prism 14 1st variable magnification lens 15 Focus lens 16 2nd variable magnification lens 17 CCD image pick-up element 18 Substrate 19 Screw 20, 30 Flexible substrate 21 Focus lens frame 211 Camera body 212 Shutter button 22, 26 Guide shaft 23 For focus Motor 24 First zoom lens frame 25 Second zoom lens frame 27 Motor for zooming 28 Deceleration gear 29 Cam rod 40 IR cut filter 200 Camera

Claims (6)

An imaging optical system;
A first step portion having an internal space for accommodating the imaging optical system, extending rearwardly in the optical axis direction on the imaging plane side, inward and outward, and having a step toward the outer side; A lens barrel provided with a rear wall portion having an opening formed with a second step portion extending in a direction surrounding the optical axis closer to the outer wall than the step portion;
An optical plate disposed on the first step;
An image sensor is mounted, and a substrate fixed to the outer wall of the rear wall in a posture in which the image sensor is inserted into the opening;
A cylindrical portion sandwiched between the optical plate material and the imaging element and pushed by both the optical plate material peripheral edge and the imaging element peripheral edge to make a round around the optical axis along the inner wall of the opening; and Extending and entering the second step portion, the deformation of the tube portion when the tube portion is pushed by the optical plate material and the imaging element, from the second step portion of the tube portion A camera module comprising: a dustproof member having a collar portion that is divided into a portion that extends toward the optical plate member and a portion that extends toward the imaging element rather than the second step portion. The second step portion is a step portion that goes around the optical axis around the inner wall of the opening,
2. The camera module according to claim 1, wherein the flange portion is an annular flange portion that extends from the tube portion and surrounds the tube portion over one turn and enters the second step portion.   The camera module according to claim 1, wherein the optical plate material is an infrared cut filter.   The camera module according to claim 1, wherein the dustproof member is a member made of rubber.   5. The bending optical system according to claim 1, wherein the imaging optical system includes a prism and is a bending optical system that reflects incident light from an object side by the prism and guides the incident light to the imaging element. Camera module. The camera module according to any one of claims 1 to 5,
A camera comprising a camera body incorporating the camera module.

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