Camera module

Abstract

A camera module 1 comprises: a lens assembly 2; an image sensor 3 that is located on the image formation side of the lens assembly 2 in the optical axis direction and receives light coming in from the lens assembly 2; a first substrate 41 that is located on the image formation side of the image sensor 3 in the optical axis direction and has the image sensor 3 mounted on the front surface thereof; a second substrate 42 that has a processing circuit 420 for processing an output signal of the image sensor 3; a flexible wiring part 43 having flexibility and electrically connecting the first substrate 41 to the second substrate 42; a heat sink 5 mounted on the image formation side of the first substrate 41 in the optical axis direction; and a cover 6 that includes a lower cover 61 connected to the heat sink 5 and serving as a heat radiation part for radiating image sensor 3 heat transmitted through the heat sink 5, and that houses the image sensor 3, the first substrate 41, a second substrate 42, the flexible wiring part 43, and the heat sink 5.

Description

Camera module CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Japanese Patent Application No. 2024-148281 (titled "Camera Module"), filed on August 30, 2024, the contents of which are incorporated herein by reference in their entirety.

[0002] The present invention relates to a camera module, and more particularly to a camera module used as a camera portion of a rearview mirror (side mirror) used in a mobile body such as an automobile.

[0003] For example, Patent Document 1 discloses a rearview imaging device in which a camera body is closely attached to an under-wing cover serving as a heat dissipation member via a highly heat-conductive sheet.

[0004] Japanese Patent Application Laid-Open No. 2022-096881

[0005] However, in the rearview camera described in Patent Document 1, heat generated by the camera is transferred from the camera body to the under-wing cover via the highly thermally conductive sheet. In other words, the camera body is interposed between the heat source in the camera and the under-wing cover, which is a heat dissipation member. As a result, the rearview camera cannot achieve sufficient heat dissipation.

[0006] The present invention has been made in view of the above points, and has an object to provide a camera module that can further improve heat dissipation.

[0007] Such an object can be achieved by the present invention (1) below.

[0008] (1) A camera module comprising: a lens assembly; an image sensor located on the imaging side of the lens assembly in the optical axis direction and receiving light entering from the lens assembly; a first substrate located on the imaging side of the image sensor in the optical axis direction and having the image sensor mounted on its front surface; a second substrate having a processing circuit for processing an output signal from the image sensor; a flexible wiring section electrically connecting the first substrate and the second substrate and having flexibility; a heat sink mounted on the imaging side of the first substrate in the optical axis direction; and a cover that houses the image sensor, the first substrate, the second substrate, the flexible wiring section, and the heat sink and that is connected to the heat sink and has a heat dissipation section that dissipates heat from the image sensor transmitted through the heat sink.

[0009] According to the camera module of the present invention, heat from the image sensor is transferred to the cover via the first substrate and the heat sink, and is then dissipated from the cover. In this way, the cover itself functions as a heat dissipation section, so the distance that heat travels from the image sensor (the heat source) to the heat dissipation section can be kept short. This results in a camera module that can demonstrate high heat dissipation performance.

[0010] FIG. 1 is a perspective view of a camera module according to a first embodiment. FIG. 2 is an exploded perspective view of the camera module shown in FIG. 1. FIG. 3 is a cross-sectional view of the camera module shown in FIG. 1. FIG. 4 is a cross-sectional view of a modified example of the camera module shown in FIG. 1. FIG. 5 is a cross-sectional view of a camera module according to a second embodiment. FIG. 6 is a cross-sectional view of a camera module according to a third embodiment. FIG. 7 is a cross-sectional view of a camera module according to a fourth embodiment. FIG. 8 is an exploded perspective view of a camera-type side mirror according to a fifth embodiment. FIG. 9 is a cross-sectional view of the camera-type side mirror shown in FIG. 8.

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A camera module according to the present invention will now be described in detail with reference to preferred embodiments shown in the accompanying drawings.

[0012] For ease of explanation, the three mutually perpendicular axes will be referred to as the X-axis, Y-axis, and Z-axis, and the direction along the X-axis will be referred to as the "X-axis direction," the direction along the Y-axis as the "Y-axis direction," and the direction along the Z-axis as the "Z-axis direction." The X-axis coincides with the optical axis O of the camera module 1. The arrow in the X-axis direction will be referred to as the "front side," and the opposite side as the "rear side." The term "orthogonal" used in this specification not only refers to the case where the two objects are orthogonal to each other, but also includes cases where the two objects are deviated from the orthogonal orientation within a range that can be considered equivalent to orthogonal from a technically common sense perspective. Similarly, the term "parallel" used in this specification not only refers to the case where the two objects are parallel to each other, but also includes cases where the two objects are deviated from the parallel orientation within a range that can be considered equivalent to orthogonal from a technically common sense perspective.

[0013] <First embodiment> Fig. 1 is a perspective view of a camera module according to a first embodiment. Fig. 2 is an exploded perspective view of the camera module shown in Fig. 1. Fig. 3 is a cross-sectional view of the camera module shown in Fig. 1. Fig. 4 is a cross-sectional view of a modified example of the camera module shown in Fig. 1.

[0014] In recent years, camera-type side mirrors (door mirrors) have become popular as side mirrors for automobiles. The camera module 1 shown in Fig. 1 can be suitably used as a camera for such camera-type side mirrors. However, the use of the camera module 1 is not particularly limited.

[0015] 2, such a camera module 1 includes a lens assembly 2 that focuses light, an image sensor 3 that receives light that has entered through the lens assembly 2, a first substrate 41 having the image sensor 3 mounted on its front surface 41a, a second substrate 42 that has a processing circuit 420 that processes an output signal from the image sensor 3, a flexible wiring portion 43 that electrically connects the first substrate 41 and the second substrate 42, a heat sink 5 mounted on the rear surface 41b of the first substrate 41, a cover 6 that covers each of these components, and a thermally conductive member 7 that connects the heat sink 5 and the cover 6. Each of these components will be described in detail below.

[0016] <Cover 6> As shown in FIG. 3 , the cover 6 houses the above-mentioned components (image sensor 3, first substrate 41, second substrate 42, flexible wiring 43, heat sink 5, and thermally conductive member 7) except for the lens assembly 2. This allows the above-mentioned components to be appropriately protected from dust, moisture, and the like. The cover 6 has a shape with a cutout at the rear (negative side in the X-axis direction) and upper part (positive side in the Z-axis direction). The cover 6 has a high-back portion 6A and a low-back portion 6B located behind (negative side in the X-axis direction) the high-back portion 6A and shorter than the high-back portion 6A. The first substrate 41 is housed in an upright position within the high-back portion 6A, and the second substrate 42 is housed in a reclining position within the low-back portion 6B. By shaping the cover 6 in this way, unnecessary space within the cover 6 can be eliminated, allowing the camera module 1 to be made smaller and lighter.

[0017] The cover 6 also has a lower cover 61 as a first cover constituting the lower portion, and an upper cover 62 as a second cover constituting the upper portion. As shown in FIG. 2 , the lower cover 61 and the upper cover 62 are fixed together with four bolts B1. By configuring the cover 6 from multiple members in this way, the ease of assembly and maintenance of the camera module 1 is improved. The upper cover 62 also has a lens assembly insertion hole 621 for inserting and fixing the lens assembly 2.

[0018] Furthermore, of the lower cover 61 and the upper cover 62, at least the lower cover 61 functions as a heat dissipation section for dissipating heat from the image sensor 3. In other words, the cover 6 has a heat dissipation section for dissipating heat from the image sensor 3. By using the cover 6 as a heat dissipation section in this way, the distance that heat travels from the image sensor 3, which is the heat source, to the heat dissipation section can be kept short, and therefore the heat from the image sensor 3 can be dissipated efficiently.

[0019] The lower cover 61 and the upper cover 62 are made of a metal material such as aluminum or stainless steel, which results in a highly rigid cover 6. The lower cover 61 also has high heat dissipation properties, allowing for efficient heat dissipation from the image sensor 3. Furthermore, not only the lower cover 61 but also the upper cover 62 can be effectively used as a heat dissipation section with high heat dissipation properties, allowing heat from the image sensor 3 to be dissipated from the entire cover 6.

[0020] The cover 6 has been described above, but the configuration of the cover 6 is not particularly limited. For example, in the cover 6 of this embodiment, the lower cover 61 and the upper cover 62 are fixed to each other by the bolt B1. However, the method for fixing them is not particularly limited, and they may be fixed to each other by, for example, an adhesive. Furthermore, for example, a sealing member (packing) may be interposed between the lower cover 61 and the upper cover 62 to improve waterproofing and dustproofing. Furthermore, the lower cover 61 and the upper cover 62 may be made of different materials.

[0021] <Lens Assembly 2> The lens assembly 2 focuses incident light toward the image sensor 3. As shown in Fig. 3 , the lens assembly 2 is inserted into a lens assembly insertion hole 621 of the cover 6. The lens assembly 2 is fixed to the cover 6 (upper cover 62) at the lens assembly insertion hole 621. The lens assembly 2 also has a cylindrical sleeve 21 extending along the optical axis O, a lens group 22 provided inside the sleeve 21, and an aperture stop and the like (not shown).

[0022] Furthermore, the lens assembly 2 of this embodiment is a single-focus (fixed-focus) lens assembly. By using a single-focus lens assembly 2, the number of lenses can be reduced compared to a lens assembly with a zoom function. This allows the lens assembly 2 to be made smaller and less expensive. Furthermore, it is easier to obtain a brighter image than a lens assembly 2 with a zoom function.

[0023] The lens assembly 2 has been described above, but there are no particular limitations on the configuration of the lens assembly 2. For example, although the lens assembly 2 in this embodiment is fixed to the cover 6, there are no particular limitations as long as the relative position with respect to the image sensor 3 is fixed, and the lens assembly 2 may be fixed to the first substrate 41 (sensor base 411, described later), for example. Furthermore, the lens assembly 2 may be a lens assembly having a zoom function.

[0024] <Image Sensor 3> As shown in FIG. 3 , the image sensor 3 is located on the imaging side (negative side in the X-axis direction) of the lens assembly 2 in the optical axis direction, and is arranged alongside the lens assembly 2 along the optical axis O. The light-receiving surface of the image sensor 3 is perpendicular to the optical axis O. The image sensor 3 receives light entering through the lens assembly 2 and outputs a photoelectric conversion signal corresponding to the received light. The image sensor 3 is not particularly limited, and a CCD image sensor, a CMOS image sensor, or the like can be used. The various specifications of the image sensor 3, such as the element size and resolution, can be set appropriately according to the specifications required for the camera module 1. In particular, when used as a camera for an automobile side mirror, the image sensor 3 is required to have high resolution, which tends to increase the amount of heat generated.

[0025] <First substrate 41> The first substrate 41 is a hard printed circuit board (rigid substrate). As shown in Fig. 3, the first substrate 41 is disposed in an upright position within the tall portion 6A of the cover 6, that is, with its main surface perpendicular to the optical axis O. The first substrate 41 is positioned directly opposite the image sensor 3 on the imaging side in the optical axis direction (the negative side in the X-axis direction). The image sensor 3 is mounted on a front surface 41a of the first substrate 41.

[0026] As shown in FIG. 2 , a frame-shaped sensor base 411 that surrounds the image sensor 3 is mounted on the front surface 41a of the first substrate 41. The sensor base 411 has a frame-shaped base 411a that surrounds the image sensor 3 and a pair of protrusions 411b that protrude forward from the base 411a. The pair of protrusions 411b are arranged side by side in the Y-axis direction, on both sides of the image sensor 3. As shown in FIGS. 2 and 3 , the sensor base 411 is fixed (co-fastened) to the first substrate 41 at the base 411a together with the heat sink 5 by bolts B2. The upper cover 62 is fixed to the pair of protrusions 411b by bolts B3. This fixes the first substrate 41 to the cover 6 via the sensor base 411.

[0027] Although the first substrate 41 has been described above, the configuration of the first substrate 41 is not particularly limited. For example, in the present embodiment, the sensor base 411 and the heat sink 5 are fastened together to the first substrate 41, but this is not limited thereto, and the sensor base 411 and the heat sink 5 may each be separately fixed to the first substrate 41. Furthermore, in the present embodiment, the first substrate 41 is fixed to the upper cover 62 via the sensor base 411, but this is not limited thereto, and for example, the sensor base 411 may be omitted and the first substrate 41 may be fixed directly to the upper cover 62.

[0028] <Second Substrate 42> Like the first substrate 41 described above, the second substrate 42 is a hard printed circuit board (rigid substrate). As shown in FIG. 3 , the second substrate 42 is located on the imaging side (negative side in the X-axis direction) of the first substrate 41 in the optical axis direction and is disposed in a lying position within the low-back portion 6B of the cover 6, i.e., with its main surface aligned with the optical axis O. In other words, the second substrate 42 is disposed in an inclined position relative to the first substrate 41. By disposing the first substrate 41 and the second substrate 42 in different positions in this manner, the degree of freedom in disposing the first substrate 41 and the second substrate 42 is increased. This makes it easier to manufacture a camera module 1 having an external shape and component arrangement suited to the installation environment.

[0029] The second substrate 42 is fixed to the upper cover 62 by a bolt B4. That is, in this embodiment, the first substrate 41 and the second substrate 42 are both fixed to the upper cover 62. This configuration improves the ease of assembly and maintenance of the camera module 1.

[0030] Furthermore, a plurality of chip components are mounted on both main surfaces of the second substrate 42. These chip components are electrically connected by wiring (not shown) provided on the second substrate 42, thereby forming a processing circuit 420. The processing circuit 420 has, for example, a function of controlling the driving of each part of the camera module 1 and a function of processing the output signal of the image sensor 3 and transferring the results (image data) to the outside.

[0031] The processing circuit 420 may be, for example, an integrated circuit (IC) such as a field-programmable gate array (FPGA), a microcontroller, or an application-specific integrated circuit (ASIC). In particular, in this embodiment, an FPGA is used as the processing circuit 420. The use of an FPGA enables arithmetic processing specialized for the camera module 1, and can increase, for example, the speed at which the output signal from the image sensor 3 is processed and the speed at which image data obtained by processing is transferred.

[0032] As described above, the second substrate 42 is located on the imaging side of the first substrate 41 in the optical axis direction (the negative side in the X-axis direction) and is spaced apart from the first substrate 41, making it difficult for heat from the image sensor 3 to be transmitted. This makes it easier to keep the processing circuit 420 within the operating temperature range, enabling stable arithmetic processing and effectively suppressing a reduction in the lifespan of the processing circuit 420 due to high temperatures. In particular, as will be described later, a heat sink 5 for transmitting heat from the image sensor 3 to the lower cover 61 is disposed between the first substrate 41 and the second substrate 42. This makes it difficult for heat from the image sensor 3 to be transmitted by the second substrate 42, making the above-described effect more pronounced.

[0033] 3 , a cable 422 is drawn from an external connection connector 421 on the second board 42 to the outside of the cover 6. Although not shown, the camera module 1 and an external device are electrically connected via the cable 422. Here, by configuring the second board 42 as a separate body from the first board 41, the degree of freedom in the placement of the second board 42 within the device is increased. Therefore, for example, the location from which the cable 422 is drawn can be set relatively freely depending on the position of the external device relative to the camera module 1. This improves the usability of the camera module 1.

[0034] The second substrate 42 has been described above, but the configuration of the second substrate 42 is not particularly limited. For example, in the present embodiment, the second substrate 42 is disposed in a position perpendicular to the first substrate 41. However, this is not limited thereto, and the second substrate 42 may be disposed in a position inclined at an angle other than perpendicular to the first substrate 41. Furthermore, for example, the second substrate 42 may be disposed in an upright position, that is, in a position parallel to the first substrate 41. Furthermore, for example, in the present embodiment, the second substrate 42 is fixed to the upper cover 62. However, this is not limited thereto, and the second substrate 42 may be fixed to the lower cover 61. Furthermore, the method of fixing the second substrate 42 to the upper cover 62 is not particularly limited.

[0035] In addition, in this embodiment, the cable 422 is drawn out from the back surface of the cover 6, but the location from which the cable 422 is drawn out is not particularly limited, and may be, for example, the side surface, top surface, or bottom surface of the low-back portion 6B. In addition, in this embodiment, the cable 422 extends from the connector 421, but this is not limited thereto, and for example, the connector 421 may be exposed to the outside of the device, and a cable on the external device side may be connected to the connector 421.

[0036] <Heat sink 5> The heat sink 5 is a heat transfer path for efficiently transferring heat from the image sensor 3 to the lower cover 61, which is a heat dissipation section. Therefore, the heat sink 5 is made of a material with high thermal conductivity, specifically, a metal material such as aluminum or stainless steel. This allows the heat from the image sensor 3 to be efficiently transferred to the lower cover 61 via the heat sink 5.

[0037] 3, the heat sink 5 is plate-shaped and is disposed in an upright position within the high back portion 6A of the cover 6, i.e., with its main surface perpendicular to the optical axis O. The heat sink 5 is mounted on the rear surface 41b of the first substrate 41, which is on the image side in the optical axis direction, and is fixed (co-fastened) to the first substrate 41 together with the sensor base 411 by bolts B2. The heat sink 5 is longer in the Z-axis direction than the first substrate 41, and its lower end extends below the first substrate 41. The lower surface of the heat sink 5 is disposed adjacent to the inner bottom surface of the lower cover 61.

[0038] Although not shown, a thermally conductive member is provided between the first substrate 41 and the heat sink 5. The thermally conductive member brings the first substrate 41 and the heat sink 5 into close contact with each other, allowing efficient heat transfer between them. This allows efficient transfer of heat from the image sensor 3 from the first substrate 41 to the heat sink 5.

[0039] The thermally conductive member is not particularly limited, but examples thereof include a thermally conductive sheet, thermally conductive grease, etc., which have high thermal conductivity. A thermally conductive sheet is, for example, a flexible resin sheet whose main component is acrylic resin, silicone resin, etc., which contains a highly thermally conductive filler such as metal or ceramic. On the other hand, a thermally conductive grease is, for example, a grease whose main component is acrylic resin, silicone resin, etc., which contains a highly thermally conductive filler such as metal or ceramic.

[0040] Although the heat sink 5 has been described above, the configuration of the heat sink 5 is not particularly limited. For example, the heat sink 5 may be in a sheet shape. Furthermore, for example, the thermally conductive member interposed between the first substrate 41 and the heat sink 5 may be omitted.

[0041] <Heat Conduction Member 7> As shown in Figure 3, the heat conduction member 7 is provided between the lower end of the heat sink 5 and the inner bottom surface of the lower cover 61, connecting them. With this configuration, heat from the image sensor 3 is conducted from the first substrate 41 to the heat sink 5 and then via the heat conduction member 7 to the lower cover 61, which serves as a heat dissipation unit. The heat is then dissipated from the lower cover 61. In this way, because the cover 6 itself functions as a heat dissipation unit, the distance that heat travels from the heat source (image sensor 3) to the heat dissipation unit (lower cover 61) can be kept short. Therefore, the camera module 1 can exhibit high heat dissipation properties.

[0042] In particular, since the heat sink 5 and the lower cover 61 are tightly attached by the heat conductive member 7, the heat from the image sensor 3 is transferred to the lower cover 61 more efficiently. This makes the heat dissipation effect described above even more pronounced. Furthermore, the heat conductive member 7 is elastic. Therefore, even if the relative positions of the heat sink 5 and the lower cover 61 change due to deformation of various parts caused by thermal expansion or the like, the elastic deformation of the heat conductive member 7 ensures that the connection between the heat sink 5 and the lower cover 61 is maintained in an optimal state. This allows the device to continuously exhibit excellent heat dissipation performance.

[0043] The thermal conductive member 7 is not particularly limited as long as it has sufficiently high thermal conductivity, and examples thereof include a thermal conductive sheet, thermal conductive grease, etc., which have high thermal conductivity. A thermal conductive sheet is, for example, a flexible resin sheet whose main component is acrylic resin, silicone resin, etc., which contains a highly thermally conductive filler such as metal or ceramic. On the other hand, a thermal conductive grease is, for example, a grease whose main component is acrylic resin, silicone resin, etc., which contains a highly thermally conductive filler such as metal or ceramic.

[0044] Although the thermal conductive member 7 has been described above, there are no particular limitations on the configuration of the thermal conductive member 7. For example, as shown in Fig. 4, the thermal conductive member 7 may be omitted and the heat sink 5 may be brought into contact with the lower cover 61 to thermally connect them.

[0045] 3 , the flexible wiring portion 43 electrically connects the first substrate 41 and the second substrate 42. This electrically connects the image sensor 3 and the processing circuit 420, allowing the processing circuit 420 to perform the functions described above. Furthermore, by connecting the first substrate 41 and the second substrate 42 with the flexible wiring portion 43, the orientation of the second substrate 42 can be changed relative to the first substrate 41. This increases the degree of freedom in the arrangement of the second substrate 42, and allows the position and orientation of the second substrate 42 to be set relatively freely to match the shape of the cover 6.

[0046] The flexible wiring section 43 is made of a flexible printed circuit board (flexible board), which simplifies the configuration of the flexible wiring section 43 and allows the first substrate 41 and the second substrate 42 to be easily connected.

[0047] As described above, the lower end of the heat sink 5 is connected to the lower cover 61 via the thermally conductive member 7. Therefore, the flexible wiring portion 43 is arranged so as to wrap around from above (the positive side in the Z-axis direction) to the rear (the negative side in the X-axis direction) of the heat sink 5. This arrangement can suppress interference between the flexible wiring portion 43 and the heat sink 5. Furthermore, partway along its length, the flexible wiring portion 43 extends along the surface of the heat sink 5, that is, along the rear surface. This configuration can reduce the space required to arrange the flexible wiring portion 43, thereby enabling the camera module 1 to be made more compact.

[0048] Although the flexible wiring unit 43 has been described above, the configuration of the flexible wiring unit 43 is not particularly limited. For example, the flexible wiring unit 43 does not have to be a flexible substrate, but may be configured as a cable group in which multiple cables are bundled together. Furthermore, the flexible wiring unit 43 may wrap around from the side (positive or negative side in the Y-axis direction) of the heat sink 5 to the rear (negative side in the X-axis direction). However, in this case, twisting may occur in the flexible wiring unit 43, and it may be necessary to shift the second substrate 42 further rearward (negative side in the X-axis direction) to accommodate this twisting. In this respect, the present embodiment is preferable, and the camera module 1 can be made smaller.

[0049] The above has described the configuration of camera module 1. As described above, camera module 1 includes lens assembly 2, image sensor 3 located on the image forming side of lens assembly 2 in the optical axis direction and receiving light entering from lens assembly 2, first substrate 41 located on the image forming side of image sensor 3 in the optical axis direction and having image sensor 3 mounted on its front surface 41 a, second substrate 42 having processing circuit 420 that processes output signals from image sensor 3, flexible wiring portion 43 that electrically connects first substrate 41 and second substrate 42, heat sink 5 mounted on rear surface 41 b of first substrate 41 that is on the image forming side in the optical axis direction, and cover 6 that houses image sensor 3, first substrate 41, second substrate 42, flexible wiring portion 43, and heat sink 5 and that includes lower cover 61 connected to heat sink 5 and serving as a heat dissipation portion that dissipates heat from image sensor 3 transmitted via heat sink 5. With this configuration, heat from the image sensor 3 is transferred to the lower cover 61, which serves as a heat dissipation section, via the first substrate 41 and the heat sink 5, and is dissipated from the lower cover 61. In this way, the cover 6 itself functions as a heat dissipation section, so the distance that heat travels from the heat source (image sensor 3) to the heat dissipation section (lower cover 61) can be kept short. Therefore, the camera module 1 can exhibit high heat dissipation properties.

[0050] Furthermore, as described above, the camera module 1 has the thermally conductive member 7 connecting the heat sink 5 and the lower cover 61. With this configuration, the heat sink 5 and the lower cover 61 are tightly attached by the thermally conductive member 7, and the heat of the image sensor 3 is more efficiently transferred to the lower cover 61. This further improves the heat dissipation performance of the camera module 1.

[0051] Furthermore, as described above, the thermally conductive member 7 has elasticity. With this configuration, even if the relative position between the heat sink 5 and the lower cover 61 changes due to deformation of various parts caused by thermal expansion or the like, the elastic deformation of the thermally conductive member 7 ensures that the connection between the heat sink 5 and the lower cover 61 is maintained in an appropriate state. Therefore, the camera module 1 can continuously exhibit excellent heat dissipation properties.

[0052] As described above, the second substrate 42 is disposed in an orientation in which the respective surfaces are inclined relative to the first substrate 41. By disposing the first substrate 41 and the second substrate 42 in different orientations in this way, the degree of freedom in the arrangement of the first substrate 41 and the second substrate 42 increases. This makes it easier to manufacture a camera module 1 having an outer shape and an arrangement of each part that are suited to the environment in which it will be installed.

[0053] As described above, the second substrate 42 is located on the imaging side of the first substrate 41 in the optical axis direction, and the heat sink 5 is located between the first substrate 41 and the second substrate 42. With this configuration, heat from the image sensor 3 is less likely to be transmitted to the second substrate 42. This makes it easier to keep the processing circuit 420 within the operating temperature range, enabling stable arithmetic processing and effectively suppressing a reduction in the lifespan of the processing circuit 420 due to high temperatures.

[0054] As described above, the flexible wiring portion 43 extends along the surface of the heat sink 5 on the image side in the optical axis direction of the heat sink 5. With this configuration, the space required for arranging the flexible wiring portion 43 can be kept small, and the camera module 1 can be made smaller.

[0055] As described above, the flexible wiring section 43 is a flexible printed circuit board, and this configuration allows the flexible wiring section 43 to have a simple configuration.

[0056] As described above, the cover 6 has the lower cover 61 as a first cover that is a heat dissipation section, and the upper cover 62 as a second cover that houses the image sensor 3, the first board 41, the second board 42, the flexible wiring section 43, and the heat sink 5 between the lower cover 61, and the first board 41 and the second board 42 are fixed to the upper cover 62. By fixing the first board 41 and the second board 42 to the upper cover 62 in this way, the ease of assembly, maintenance, etc. of the camera module 1 is improved.

[0057] Second Embodiment FIG. 5 is a cross-sectional view of a camera module according to a second embodiment.

[0058] The camera module 1 of this embodiment is similar to the camera module 1 of the first embodiment described above, except that a fin 611 is provided on the lower cover 61. Therefore, in the following description, differences between this embodiment and the first embodiment will be mainly described, and descriptions of similar points will be omitted. Furthermore, in the drawings of this embodiment, the same reference numerals are used to designate the same components as those in the previously described embodiment.

[0059] 5, in the camera module 1 of this embodiment, a plurality of fins 611 are provided on the lower cover 61, which is a heat dissipation section. With this configuration, the surface area of ​​the lower cover 61 is increased, and the heat dissipation ability of the lower cover 61 is improved accordingly. Therefore, heat from the image sensor 3 can be dissipated more efficiently.

[0060] The second embodiment can also achieve the same effects as the first embodiment.

[0061] Third Embodiment FIG. 6 is a cross-sectional view of a camera module according to a third embodiment.

[0062] The camera module 1 of this embodiment is similar to the camera module 1 of the first embodiment described above, except that the heat sink 5 is connected to a different destination. Therefore, in the following description, differences between this embodiment and the first embodiment will be mainly described, and descriptions of similar points will be omitted. Furthermore, in the drawings of this embodiment, the same reference numerals are used to designate the same components as those in the previously described embodiment.

[0063] 6, in the camera module 1 of this embodiment, the upper end of the heat sink 5 is connected to the upper cover 62 via the thermally conductive member 7. In this configuration, of the lower cover 61 and the upper cover 62 that constitute the cover 6, at least the upper cover 62 functions as a heat dissipation part.

[0064] In this way, because the upper end of the heat sink 5 is connected to the upper cover 62 via the thermally conductive member 7, the flexible wiring portion 43 is arranged to wrap around from below (the negative Z-axis direction) to the rear (the negative X-axis direction) of the heat sink 5. With this arrangement, interference between the flexible wiring portion 43 and the heat sink 5 can be suppressed.

[0065] The third embodiment can also achieve the same effects as the first embodiment.

[0066] Fourth Embodiment FIG. 7 is a cross-sectional view of a camera module according to a fourth embodiment.

[0067] The camera module 1 of this embodiment is similar to the camera module 1 of the first embodiment described above, except for the configuration of the connection portion between the heat sink 5 and the lower cover 61. Therefore, in the following description, the differences between this embodiment and the first embodiment will be mainly described, and a description of similar points will be omitted. Furthermore, in the drawings of this embodiment, the same reference numerals are used to designate similar components to those in the previously described embodiment.

[0068] 7 , in the camera module 1 of this embodiment, a recess 612 is provided on the inner surface of the lower cover 61. The lower end of the heat sink 5 is inserted into this recess 612. Furthermore, the recess 612 is filled with a thermally conductive member 7, which contacts not only the lower surface of the heat sink 5 but also the entire periphery of the base end (the lower surface, front surface, rear surface, and both side surfaces). With this configuration, the contact area between the heat sink 5 and the lower cover 61 and the thermally conductive member 7 is increased compared to the first embodiment described above, and heat from the image sensor 3 can be transferred to the lower cover 61 more efficiently.

[0069] The fourth embodiment can also achieve the same effects as the first embodiment.

[0070] <Fifth embodiment> Fig. 8 is an exploded perspective view of a camera-type side mirror according to a fifth embodiment, and Fig. 9 is a cross-sectional view of the camera-type side mirror shown in Fig. 8 .

[0071] The camera module 1 of this embodiment is similar to the camera module 1 of the first embodiment described above, except for the configuration of the cover 6. Therefore, in the following description, differences between this embodiment and the first embodiment will be mainly described, and descriptions of similar points will be omitted. Furthermore, in each drawing of this embodiment, the same reference numerals are used to designate similar components to those of the above-described embodiment.

[0072] As shown in Fig. 8, the camera module 1 of this embodiment is used as a camera for a camera-type side mirror 91 of a vehicle 9. Also, as shown in Fig. 9, the lower cover 61 also serves as a frame 911 that is attached to the vehicle 9. In this way, the lower cover 61 also serves as the frame 911, thereby enabling the camera-type side mirror 91 to be made smaller. Furthermore, the lower cover 61 is more susceptible to wind when the vehicle is traveling. This improves the heat dissipation properties of the lower cover 61.

[0073] The camera-type side mirror 91 further has a lower frame cover 912 and an upper frame cover 913 that cover the frame 911 from above and below. With this configuration, the camera module 1 can be covered and hidden, improving the aesthetic appeal of the camera-type side mirror 91.

[0074] The fifth embodiment as described above can also achieve the same effects as the first embodiment.

[0075] While the camera module of the present invention has been described above based on the illustrated embodiments, the present invention is not limited thereto, and the configuration of each part can be replaced with any configuration having a similar function. Furthermore, any other configuration may be added to the present invention. Furthermore, the above-described embodiments may be combined as appropriate.

[0076] According to the camera module of the present invention, heat from the image sensor is transferred to the cover via the first substrate and the heat sink, and is then dissipated from the cover. Because the cover itself functions as a heat dissipation section, the distance that heat travels from the image sensor, which is the heat source, to the heat dissipation section can be kept short. This results in a camera module that can exhibit high heat dissipation performance. Therefore, the present invention has industrial applicability.

Claims

1. A camera module comprising: a lens assembly; an image sensor located on the imaging side of the lens assembly in the optical axis direction and receiving light entering from the lens assembly; a first board located on the imaging side of the image sensor in the optical axis direction and having the image sensor mounted on its front surface; a second board having a processing circuit for processing an output signal from the image sensor; a flexible wiring section that electrically connects the first board and the second board and has flexibility; a heat sink mounted on the imaging side of the first board in the optical axis direction; and a cover that is connected to the heat sink and has a heat dissipation section that dissipates heat from the image sensor that is transmitted via the heat sink, and that houses the image sensor, the first board, the second board, the flexible wiring section and the heat sink.

2. The camera module according to claim 1, further comprising a thermally conductive member connecting said heat sink and said heat dissipation portion.

3. The camera module according to claim 2, wherein the heat conducting member has elasticity.

4. The camera module according to claim 1, wherein the second substrate is disposed with its respective surfaces tilted relative to the first substrate.

5. A camera module as described in claim 1, wherein the second substrate is located on the imaging side of the first substrate in the optical axis direction, and the heat sink is located between the first substrate and the second substrate.

6. The camera module according to claim 1, wherein the flexible wiring section extends along the surface of the heat sink on the image side of the heat sink in the optical axis direction.

7. The camera module according to claim 1, wherein the flexible wiring section is a flexible printed circuit board.

8. The camera module according to claim 1, wherein the cover comprises a first cover having the heat dissipation portion and a second cover accommodating the image sensor, the first substrate, the second substrate, the flexible wiring portion and the heat sink between the first cover and the second cover, and the first substrate and the second substrate are fixed to the second cover.

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