JP2011217291A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat dissipation structure effective for an imaging element in an imaging device having the imaging element which is surface-mounted to a substrate.SOLUTION: The imaging device comprises a lens unit 1 having a built-in lens 13, a metal plate 5 fixed to the lens unit 1, an imaging element 2 fixed in a predetermined position and a posture relative to the metal plate 5, and the imaging element 2 which is surface-mounted to a substrate 3. At a rear side of the substrate 3, a radiator plate 4 is set, and on a surface of the radiator plate 4, a convex portion 41 is formed toward a rear surface of the imaging element 2. The substrate 3 has an opening 31 which the convex portion 41 of the radiator plate 4 penetrates, and a surface of the convex portion 41 of the radiator plate 4 is in direct contact with a rear surface of the imaging element 2.

Description

  The present invention relates to an image pickup apparatus in which light that has passed through a lens is incident on the surface of an image pickup device to pick up an image.

In this type of image pickup apparatus, as shown in FIG. 2, an image pickup device (20) such as a CCD is surface-mounted on a flexible lead substrate (30), and the side surface of the image pickup device (20) is an adhesive (70). Is bonded to the surface of the flexible lead substrate (30).
A metal plate (50) is fixed to the back surface of the image sensor (20) by an adhesive (80), and the metal plate (50) is fastened and fixed to a lens unit (not shown).

In the imaging device, when the metal plate (50) is fixed to the imaging device (20), the imaging surface of the imaging device (20) is in a predetermined position with respect to the surface (reference surface) of the metal plate (50). Position adjustment is performed so that it becomes a posture.
Thereafter, the metal plate (50) is fastened and fixed to the lens unit (not shown), so that the imaging device (20) is accurately positioned with respect to the lens unit.

By the way, when, for example, a CMOS is adopted as the image pickup element (20), the CMOS generates a larger amount of heat than the CCD, and thus some heat dissipation structure is required.
In the case of the imaging apparatus shown in FIG. 2, the metal plate (50) exhibits a slight heat dissipation function, but an adhesive (80) is interposed between the imaging element (20) and the metal plate (50). There is a problem that heat conduction from the image pickup element (20) to the metal plate (50) is poor, and a sufficient heat radiation effect cannot be obtained depending on the metal plate (50).

2. Description of the Related Art Conventionally, a heat dissipation structure for an image pickup apparatus has been proposed in which a heat sink is directly in contact with the back surface of an image sensor (Patent Document 1).
However, since the heat dissipation structure is intended for an image sensor having a plurality of leads projecting from the side surface, a heat sink is brought into contact with and fixed to the back surface of the image sensor. It cannot be employed in an image pickup apparatus having a surface-mount image pickup element covered with a substrate.

JP 2009-147485 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an effective heat dissipation structure for an image pickup device in an image pickup apparatus in which the image pickup device is surface-mounted on a substrate.

The imaging apparatus according to the present invention includes a lens unit (1) having a built-in lens (13), a metal plate (5) fixed to the lens unit (1), and a predetermined amount with respect to the metal plate (5). The image pickup device (2) is fixed in position and orientation, and the image pickup device (2) is surface-mounted on the substrate (3).
Here, a heat radiating plate (4) is installed on the back side of the substrate (3), and a convex portion (41) is formed on the surface of the heat radiating plate (4) toward the back surface of the image sensor (2). In addition, the substrate (3) is formed with an opening (31) through which the convex portion (41) of the heat radiating plate (4) passes, and the surface of the convex portion (41) of the heat radiating plate (4) is imaged. It is in direct contact with the back of the element (2).

According to the imaging apparatus, heat generated from the imaging element (2) is transmitted to the heat radiating plate (4), transmitted from the heat radiating plate (4) to the surrounding air, or in contact with the heat radiating plate (4). The image sensor (2) is prevented from overheating.
Here, since the surface of the convex part (41) of the heat sink (4) is in direct contact with the back surface of the image sensor (2), the heat conduction from the image sensor (2) to the heat sink (4) is It is done efficiently.

In a specific embodiment, the heat radiating plate (4) is provided in a rear surface region of the imaging element (2) exposed from the opening (31) of the substrate (3) in a surface region surrounding the convex portion (41). It is fixed with an adhesive (7).
According to this specific aspect, the surface of the heat sink (4) is firmly bonded and fixed to the back surface of the image sensor (2).

In a more specific embodiment, at least a part of the heat radiating plate (4) is parallel to the metal plate (5) through a space formed between the substrate (3) and the metal plate (5). It has spread to.
According to the specific embodiment, a large area heat radiation surface can be secured on the front and back surfaces of the metal plate (5).

  ADVANTAGE OF THE INVENTION According to this invention, the effective thermal radiation structure with respect to an image pick-up element is obtained in the image pick-up device which mounted the image pick-up element on the board | substrate.

FIG. 1 is a cross-sectional view showing a main part of an imaging apparatus according to the present invention. FIG. 2 is a cross-sectional view of a conventional imaging device. FIG. 3 is an exploded perspective view of the imaging apparatus according to the present invention. 4 is an exploded perspective view of the imaging apparatus viewed from a direction different from that in FIG.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
As shown in FIG. 1, an image pickup apparatus according to the present invention includes a lens unit (1) having a built-in lens (13), and an image pickup element (2) made of CMOS to which light that has passed through the lens (13) should enter. The image pickup device (2) is surface-mounted on the flexible lead substrate (3).
A plurality of bosses (12) project from the lens unit (1), and a metal plate (5) is fastened and fixed to the bosses (12) by screws (6). The metal plate (5) On top of this, the image pickup device (2) is mounted via a heat sink (4) made of Cu.

As shown in FIGS. 3 and 4, the lens unit (1) includes a lens (13) and a plurality of parts (14) and (15) on a frame (11) provided with the plurality of bosses (12). It is configured with an attached.
The heat radiating plate (4) is installed on the back side of the flexible lead substrate (3), and a convex portion (41) is formed on the surface of the heat radiating plate (4) toward the image sensor (2). Yes.
The flexible lead substrate (3) has an opening (31) through which the convex portion (41) of the heat radiating plate (4) passes.
The metal plate (5) has an opening (51).

As shown in FIG. 1, the convex portion (41) of the heat radiating plate (4) passes through the opening (31) of the flexible lead substrate (3), and the surface of the convex portion (41) is the back surface of the imaging device (2). Is in direct contact.
Then, the heat radiating plate (4) is bonded to the back surface region of the imaging element (2) exposed from the opening (31) of the flexible lead substrate (3) in the surface region surrounding the convex portion (41). ).
Thus, an image sensor unit in which the image sensor (2) and the heat sink (4) are integrated is configured.

The heat radiating plate (4) is fixed to the metal plate (5) by filling the back surface of the heat radiating plate (4) with an adhesive (8) from the opening (51).
The central portion of the heat radiating plate (4) extends a flat space formed between the flexible lead substrate (3) and the metal plate (5) in parallel with the metal plate (5). The front and back surfaces are secured as heat dissipation surfaces.

  In assembling the image pickup device, first, the image pickup device (2) and the heat radiating plate (4) mounted on the surface of the flexible lead substrate (3) are integrated with an adhesive (7) to obtain the image pickup device unit. Make it. At this time, high assembly accuracy is not required between the image pickup element (2) and the heat sink (4).

  Next, necessary adjustments (tilt adjustment, etc.) are performed so that the image pickup surface A of the image pickup device (2) is in a predetermined position and posture with respect to the surface (reference surface B) of the metal plate (5). In this position and posture, the adhesive (8) is filled and solidified, and the metal plate (5) is fixed to the heat radiating plate (4).

Thereafter, the metal plate (5) is fastened and fixed to the plurality of bosses (12) of the lens unit (1) using a plurality of screws (6).
As a result, the imaging surface A of the imaging device (2) is accurately positioned with respect to the lens (13) of the lens unit (1).

According to the above imaging device, the heat generated from the imaging element (2) is transmitted to the heat radiating plate (4) by heat conduction, and is dissipated from the heat radiating plate (4) to the surrounding air by heat transfer.
Here, since the surface of the convex part (41) of the heat sink (4) is in direct contact with the back surface of the image sensor (2), the heat conduction from the image sensor (2) to the heat sink (4) is It is done efficiently.
Moreover, the heat radiation plate (4) has a wide heat radiation surface on the front and back surfaces, so that heat can be efficiently dissipated into the air.
As a result, overheating of the image sensor (2) is effectively prevented.

In addition, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim. For example, the imaging device (2) is not limited to a CMOS, and various known imaging devices such as a CCD can be employed.
In addition, by bringing the end of the heat sink (4) into contact with other surrounding members (heat sinks), the heat generated from the image pickup device (2) is guided from the heat sink (4) to the other members. It is also possible to prevent overheating of (2).

(1) Lens unit
(12) Boss
(13) Lens
(2) Image sensor
(3) Flexible lead board
(31) Opening
(4) Heat sink
(41) Convex
(5) Metal plate
(6) Screw
(7) Adhesive
(8) Adhesive

Claims (3)

  A lens unit including a lens, a metal plate fixed to the lens unit, and an image sensor fixed at a predetermined position and posture with respect to the metal plate. The image sensor is surface-mounted on a substrate. In the imaging apparatus in which the light passing through the lens is incident on the surface of the imaging device and imaging is performed, a heat radiating plate is installed on the back side of the substrate, and on the surface of the heat radiating plate, the back surface of the imaging device A convex portion is formed on the substrate, and an opening through which the convex portion of the heat radiating plate passes is formed in the substrate, and the surface of the convex portion of the heat radiating plate is in direct contact with the back surface of the image sensor. An imaging apparatus characterized by the above.   The imaging apparatus according to claim 1, wherein the heat radiating plate is fixed to a back surface region of the imaging element exposed from the opening of the substrate by an adhesive in a surface region surrounding the convex portion.   The imaging device according to claim 1, wherein at least a part of the heat radiating plate extends a space formed between the substrate and the metal plate in parallel with the metal plate.

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