Imaging device

Abstract

Provided is an imaging device which is more compact and has improved heat dissipation efficiency. n imaging device according to the present invention comprises: a first substrate (19) which has a first mounting surface (19b) on which an imaging element (19a) is mounted; a second substrate (20) which has a second mounting surface (20d) on which a processing module (20a) for processing imaging element output signals is mounted; a lens unit (14) which guides light to the imaging element; and a housing (5) which accommodates the first substrate, the second substrate and the lens unit, wherein the first substrate is positioned such that the first mounting surface intersects the optical axis direction, and the second substrate is positioned such that the second mounting surface intersects the optical axis direction, and a gap (22) is formed with the first substrate along the optical axis direction.

Description

Imaging device

[0001] The present invention relates to an imaging device.

[0002] 2. Description of the Related Art In an imaging device in which light collected by a lens is focused on an imaging element to form an image, there are known techniques for dissipating heat from the imaging device (see, for example, Patent Documents 1 and 2).

[0003] JP 2020-065958 A JP 2017-040723 A

[0004] In the imaging device of Patent Document 1, the board on which the heat-sensitive imaging element is mounted and the board on which components that generate a large amount of heat are mounted are separated, but from the viewpoint of miniaturizing the imaging device, there is room for improvement in the arrangement of each board.Similarly, in order to miniaturize the imaging device of Patent Document 2, it is necessary to devise an arrangement of the board on which the heat-sensitive imaging element is mounted and the board on which components that generate a large amount of heat are mounted.

[0005] The present invention has been made in view of the above-mentioned circumstances, and has an object to provide an imaging device that achieves both improved heat dissipation efficiency and miniaturization.

[0006] (Invention 1) In order to solve the above problem, the imaging device of the present invention comprises a first substrate having a first mounting surface on which an imaging element is mounted, a second substrate having a second mounting surface on which a processing module that processes an output signal of the imaging element is mounted, a lens unit that guides light to the imaging element, and a housing that houses the first substrate, the second substrate, and the lens unit, wherein the first substrate is arranged so that the first mounting surface intersects with the optical axis direction, and the second substrate is arranged so that the second mounting surface intersects with the optical axis direction, with a gap between it and the first substrate along the optical axis direction.

[0007] Furthermore, the following configurations can be exemplified as preferred embodiments of the present invention.

[0008] (Invention 2) The imaging device according to (Invention 1), wherein the first substrate has a heat transfer pattern that dissipates heat generated on the first mounting surface.

[0009] (Invention 3) The imaging device according to (Invention 2), wherein the heat transfer pattern is provided around the imaging element on the first mounting surface.

[0010] (Invention 4) The imaging device according to (Invention 1), wherein the housing includes a lens unit case that holds the lens unit, and the lens unit case is in thermal contact with the first mounting surface.

[0011] (Invention 5) The imaging device according to (Invention 1), further comprising a flexible conductive member connecting the first substrate and the second substrate.

[0012] (Invention 6) The imaging device according to (Invention 1), wherein the amount of heat generated by the second substrate is greater than the amount of heat generated by the first substrate.

[0013] (Invention 7) The imaging device according to (Invention 1), wherein the processing module has a function of converting a parallel signal from the imaging element into a serial signal and transmitting the serial signal.

[0014] (Invention 8) The imaging device described in (Invention 1) above, further comprising a cable for outputting a signal to an external device, the cable being connected to the second substrate, and heat from the second substrate being released to the outside via the cable.

[0015] (Invention 9) The imaging device described in (Invention 8) above, wherein the second mounting surface has a connection port for the cable and a heat transfer pattern provided around the connection port for dissipating heat generated on the second mounting surface.

[0016] (Invention 10) The imaging device according to (Invention 1), further comprising a spacer member for maintaining the gap.

[0017] (Invention 11) The imaging device according to (Invention 10), wherein the first substrate and the second substrate are disk-shaped.

[0018] (Invention 12) The imaging device according to (Invention 11), wherein one end of the spacer member engages with a first notch provided on the periphery of the first substrate, and the other end abuts against the second substrate.

[0019] (Invention 13) An imaging device as described in (Invention 12) above, which has a positioning member that positions the second substrate circumferentially relative to the first substrate, and the positioning member engages with a second notch portion provided on the peripheral edge of the first substrate and a third notch portion provided on the peripheral edge of the second substrate.

[0020] (Invention 14) The imaging device according to (Invention 1), further comprising a bracket for holding the housing, the bracket being in thermal contact with the housing.

[0021] (Invention 15) The imaging device described in (Invention 1) above, wherein the first substrate and the second substrate are arranged so that the surface of the first substrate opposite the first mounting surface faces the surface of the second substrate opposite the second mounting surface.

[0022] According to the present invention, it is possible to provide an imaging device that achieves both improved heat dissipation efficiency and miniaturization. Note that problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments.

[0023] 1 is an explanatory diagram showing the configuration of a head-detached camera. FIG. 1 is an exploded perspective view of a camera head. FIG. 2 is a longitudinal cross-sectional view of a camera head. FIG. 3 is an exploded perspective view of an imaging unit. FIG. 4 is an exploded perspective view of an imaging unit. FIG. 5 is an external perspective view of an imaging unit. FIG. 6 is an external perspective view of an imaging unit. FIG. 7 is a side view of a board unit. FIG. 8 is an exploded perspective view of a tip of a camera head. FIG. 9 is an explanatory diagram of an air layer in a front case. FIG. 10 is a front view of an LED board. FIG. 11 is a perspective view showing a longitudinal cross-section of a camera head. FIG. 12 is an explanatory diagram showing a heat source of a head-detached camera. FIG. 13 is an explanatory diagram showing heat transfer in a camera head. FIG. 14 is a longitudinal cross-sectional view of a camera head according to embodiment 2. FIG. 15 is an explanatory diagram showing heat transfer in a camera head according to embodiment 2. FIG. 16 is a longitudinal cross-sectional view of a camera head according to embodiment 3. FIG. 17 is an explanatory diagram showing heat transfer in a camera head according to embodiment 3. FIG. 18 is an explanatory diagram showing a sensor board and a signal transmission board according to a modified example.

[0024] Hereinafter, an embodiment of the invention will be described with reference to the drawings. This embodiment realizes an imaging device that achieves both improved heat dissipation efficiency and compactness, thereby contributing to "9. Build resilient infrastructure, promote inclusive and sustainable industrialization, foster innovation and promote resilience" of the Sustainable Development Goals (SDGs) advocated by the United Nations.

[0025] [Embodiment 1] Fig. 1 is an explanatory diagram showing the configuration of a head-detachable camera 1, Fig. 2 is an exploded perspective view of a camera head 2, and Fig. 3 is a vertical cross-sectional view of the camera head 2. In Figs. 1 to 3, the symbol L indicates the optical axis. As shown in Figs. 1 to 3, the head-detachable camera 1 has a camera head 2, a camera control unit 3, and a cable 4. The cable 4 connects the camera head 2 and the camera control unit 3. The camera control unit 3 controls the camera head 2. The camera head 2 is an example of an imaging device.

[0026] For ease of explanation, in this specification, the upstream direction in the traveling direction of light incident on the camera head 2 is defined as the front, and the downstream direction as the rear. That is, the left direction in Fig. 3 is the front, and the right direction in Fig. 3 is the rear. Therefore, of both ends of the camera head 2, the end closest to the subject is the front end of the camera head 2, and the other end farther from the subject is the rear end of the camera head 2.

[0027] In addition, in this specification, the term "thermal contact" is used to mean a state in which heat from one member can be transferred to the other member. For example, if metal members are in physical contact with each other and heat from one metal member can be transferred to the other metal member, this state is considered to be thermal contact. If members are in contact with each other via a heat transfer member and heat can be transferred from one member to the other member via the heat transfer member, this state is also considered to be thermal contact. Furthermore, if heat can be transferred between members, they are in thermal contact even if they are not in physical contact with each other. For example, if members are arranged with a small gap between them and heat from one member can be transferred to the other member through the gap, the two members are in thermal contact. On the other hand, if heat cannot be transferred between members even when they are in physical contact with each other, this state is not considered to be thermal contact.

[0028] The camera head 2 has a housing 5. The housing 5 is a casing that houses optical components and electrical components of the camera head 2, which will be described later. The housing 5 can be attached to a bracket 6. The bracket 6 holds the housing 5.

[0029] The bracket 6 has a cylindrical tube portion 6a and a flange 6b. The housing 5 is inserted into the tube portion 6a. With the housing 5 inserted into the tube portion 6a, the housing 5 is fixed in a predetermined position on the bracket 6 by inserting screws (not shown) into screw holes provided in the tube portion 6a. The tube portion 6a of the bracket 6 and the housing 5 are made of metal and are in thermal contact with each other. Therefore, heat from the housing 5 can be released to the outside of the camera head 2 (e.g., the atmosphere) via the bracket 6.

[0030] The camera head 2 has an LED cover 7, an LED board 8, a front case 9, a heat insulating ring 10, an imaging unit 11, and a rear case 12. The LED cover 7, the LED board 8, the front case 9, the heat insulating ring 10, the imaging unit 11, and the rear case 12 are arranged side by side on the optical axis L.

[0031] The imaging unit 11 has a lens unit 14 and a lens unit case 15 that houses the lens unit 14. The housing 5 is cylindrical overall and includes a front case 9, a lens unit case 15, and a rear case 12. The front case 9, the lens unit case 15, and the rear case 12 are made of a non-ferrous metal material with good thermal conductivity, such as aluminum.

[0032] The front case 9 is cylindrical and is screwed onto the lens unit case 15 via a heat insulating ring 10 (see FIG. 9). This allows the lens unit case 15 to be easily connected to the front case 9 and also suppresses heat transfer between the front case 9 and the lens unit case 15. Of course, the front case 9 and the lens unit case 15 may be connected by a connection means other than screwing (for example, fitting). A waterproof packing (not shown) is provided at the connection portion between the front case 9 and the lens unit case 15.

[0033] The LED board 8 has an annular shape and is disposed forward of the front case 9 (closer to the subject) in the direction of the optical axis of light incident on the lens unit 14.

[0034] The LED cover 7 is a transparent member. The LED cover 7 is attached to the front case 9 by welding, for example, and covers the LED board 8. Of course, the LED cover 7 may be attached to the front case 9 by other connecting means.

[0035] The rear case 12 is cylindrical. The rear case 12 is screwed into the lens unit case 15. This allows the rear case 12 and the lens unit case 15 to be easily connected and also suppresses heat transfer between the rear case 12 and the lens unit case 15. Of course, the rear case 12 and the lens unit case 15 may be connected by a connection means other than screwing (for example, a connection using a cam mechanism or a slide mechanism, or by directly fitting the two together). Note that a waterproof packing (not shown) is provided at the connection portion between the rear case 12 and the lens unit case 15.

[0036] Next, details of the imaging unit 11 will be described. Figures 4 and 5 are exploded perspective views of the imaging unit 11, and Figures 6 and 7 are external perspective views of the imaging unit 11. As shown in Figures 4 to 7, the imaging unit 11 has a lens unit 14, a lens unit case 15, and a board unit 16. The lens unit 14, the lens unit case 15, and the board unit 16 are arranged side by side on the optical axis L.

[0037] The lens unit 14 includes a lens barrel 17 and a lens 18. The lens barrel 17 is cylindrical. The lens barrel 17 houses the lens 18.

[0038] The lens unit case 15 is generally cylindrical overall. The lens unit case 15 has a female thread portion 15a on its inner periphery. The lens barrel 17 has a male thread portion 17a on its outer periphery. The lens unit case 15 is connected to the lens barrel 17 by threading the female thread portion 15a into the male thread portion 17a. As a result, the lens unit case 15 accommodates the lens unit 14 therein and restricts movement of the lens unit 14 in the optical axis direction, holding it in a predetermined position.

[0039] The board unit 16 has a sensor board 19, a signal transmission board 20, and an LED driver board 21. The board unit 16 is housed in the rear case 12 (see FIGS. 2 and 3).

[0040] The sensor substrate 19 is a disk-shaped single-layer substrate. The sensor substrate 19 has a sensor mounting surface 19b (first mounting surface) on which an image sensor 19a is mounted. The image sensor 19a is, for example, a complementary metal-oxide-semiconductor (CMOS) or a charge-coupled device (CCD).

[0041] The sensor mounting surface 19b has a copper pattern 19e made of copper foil around the imaging element 19a. Therefore, heat from the sensor board 19 is efficiently dissipated via the copper pattern 19e. The copper pattern 19e is an example of a heat transfer pattern.

[0042] The lens unit case 15 has a surface 15b at its rear end that contacts the copper pattern 19e on the sensor mounting surface 19b. Surface 15b contacts the copper pattern 19e around the imaging element 19a without touching it. In other words, surface 15b of the lens unit case 15 contacts the sensor board 19 (copper pattern 19e) while avoiding the imaging element 19a. By contacting surface 15b with copper pattern 19e, heat generated on the sensor board 19 (mainly the imaging element 19a) moves from the copper pattern 19e to surface 15b and is released from the lens unit case 15 to the outside of the camera head 2 (e.g., the atmosphere). This prevents the temperature of the sensor board 19 from rising and reduces the impact of heat on the imaging element 19a.

[0043] The signal transmission board 20 is a disk-shaped single-layer board. The signal transmission board 20 has a module mounting surface 20d (second mounting surface) on which a Ser (Serializer) 20a, a DC / DC converter 20b (see FIG. 14), and an LDO (Low Dropout) regulator 20c (see FIG. 14) are mounted. The sensor board 19 and the signal transmission board 20 are arranged so that the surface of the sensor board 19 opposite the sensor mounting surface 19b faces the surface of the signal transmission board 20 opposite the module mounting surface 20d. That is, the sensor board 19 and the signal transmission board 20 are erected so that the back surfaces of the sensor board 19 and the signal transmission board 20 face each other. This arrangement prevents heat generated by the Ser 20a (high heat generation) mounted on the module mounting surface 20d from transferring to the sensor board 19.

[0044] The LED driver board 21 has a drive section (drive unit) that drives the LEDs. The LED driver board 21 is a single-layer board. The LED driver board 21 is connected to the LED board 8 via lead wires (not shown). The LED driver board 21 is an example of a drive board.

[0045] The signal transmission board 20 is connected to the camera control unit 3 via the cable 4 (see FIGS. 3 and 12). The signal transmission board 20 converts the parallel signal output by the image sensor 19a into a serial signal (processes the output signal) and transmits the serial signal to the camera control unit 3 via the cable 4.

[0046] The sensor mounting surface 19b of the sensor board 19, the module mounting surface 20d of the signal transmission board 20, and the mounting surface of the LED driver board 21 are all arranged perpendicular to the optical axis L. In other words, the in-plane directions of the sensor board 19, the signal transmission board 20, and the LED driver board 21 are each perpendicular to the optical axis L. The sensor board 19, the signal transmission board 20, and the LED driver board 21 are arranged in this order from upstream to downstream in the propagation direction (incident direction) of light entering the lens unit 14. The sensor board 19, the signal transmission board 20, and the LED driver board 21 are also spaced apart (i.e., spaced apart) from one another in the optical axis direction. Note that the mounting surfaces of the sensor board 19, the signal transmission board 20, and the LED driver board 21 do not necessarily have to be perpendicular to the optical axis direction; they may simply intersect the optical axis direction to a degree that they are substantially perpendicular.

[0047] The sensor substrate 19 is an example of a first substrate, and the signal transmission substrate 20 is an example of a second substrate. The signal transmission substrate 20 is an example of a processing module.

[0048] The lens unit case 15 has a spacer member 15c and a positioning member 15d. The spacer member 15c and the positioning member 15d are rod-shaped members that extend downstream, i.e., rearward, in the traveling direction of light that enters the lens 18 from the lens unit case 15. The positioning member 15d is a member that is longer in the axial direction than the spacer member 15c.

[0049] The sensor substrate 19 has cutouts 19c and 19d on its periphery. The signal transmission substrate 20 has a cutout 20e on its periphery. The cutout 19c is a recess shaped to fit the spacer member 15c. The cutouts 19d and 20e are recesses shaped to fit the positioning member 15d.

[0050] 6 , for example, the spacer member 15c engages with the notch 19c and abuts against the back surface of the module mounting surface 20d of the signal transmission board 20 (i.e., the surface of the signal transmission board 20 facing the sensor board 19). In this way, the spacer member 15c is fixed to the sensor board 19. Note that the spacer member 15c may also be fixed to the sensor board 19 via an adhesive filled between the spacer member 15c and the notch 19c. The spacer member 15c abuts against the signal transmission board 20 while maintaining a constant distance between the sensor board 19 and the signal transmission board 20 in the optical axis direction, thereby positioning the signal transmission board 20 relative to the lens unit case 15 in the optical axis direction.

[0051] 7 , the positioning member 15d extends to the rear of the signal transmission board 20 and is longer in the axial direction than the spacer member 15c. The positioning member 15d engages with the notch 19d of the sensor board 19 and also engages with the notch 20e of the signal transmission board 20. In this manner, the positioning member 15d is fixed to the sensor board 19 and the signal transmission board 20. The positioning member 15d may also be fixed to the sensor board 19 and the signal transmission board 20 by adhesive filled between the positioning member 15d and the notch 19d and the notch 20e. The positioning member 15d positions the sensor board 19 and the signal transmission board 20 in the circumferential direction of the housing 5 by engaging with the notch 19d and the notch 20e.

[0052] The notch 19c is an example of a first notch provided in the first substrate, the notch 19d is an example of a second notch provided in the first substrate, and the notch 20e is an example of a third notch provided in the second substrate.

[0053] Here, the signal transmission board 20 is indirectly in contact with the lens unit case 15 via the spacer member 15c and the positioning member 15d. That is, the signal transmission board 20 is not in physical contact with the lens unit case 15. Furthermore, the signal transmission board 20 is not in physical contact with the rear case 12. This prevents heat from the signal transmission board 20 from transferring to the lens unit case 15 or the rear case 12. Furthermore, the heat from the signal transmission board 20 can be reliably released to the outside of the camera head 2, for example, into the atmosphere, via the cable 4. That is, in the first embodiment, the heat from the signal transmission board 20 can be released into the atmosphere from the cable 4 without transferring to the housing 5.

[0054] The signal transmission board 20 also has copper patterns 20f made of copper foil on both sides. In particular, the copper pattern 20f is formed on the module mounting surface 20d around the connection port for the cable 4. This can improve the heat dissipation effect of the signal transmission board 20. More specifically, heat generated on the module mounting surface 20d is released by convection or radiation via the copper patterns 20f, improving the heat dissipation effect of the signal transmission board 20.

[0055] Next, the details of the substrate unit 16 will be described. FIG. 8 is a side view of the substrate unit 16. As shown in FIG. 8, the sensor substrate 19 is connected to the signal transmission substrate 20 via FPC (Flexible Printed Circuits) 13, which is a heat insulating member. The FPC 13 is an example of a flexible conductive member. As described above, a constant distance is maintained between the sensor substrate 19 and the signal transmission substrate 20 in the optical axis direction via the spacer member 15c. Therefore, there is a gap 22 between the sensor substrate 19 and the signal transmission substrate 20.

[0056] Because air has a lower thermal conductivity than the copper pattern, the gap 22 functions as a heat insulating member. In other words, the gap 22 is a heat insulating layer that prevents heat from the signal transmission board 20 from transferring to the image sensor 19a or the lens unit 14. Heat generated in the signal transmission board 20 is released into the atmosphere mainly via the cable 4. On the other hand, heat generated in the sensor board 19 is released to the outside of the camera head 2 (e.g., the atmosphere) mainly via the lens unit case 15 (and further via the bracket 6). In this way, in embodiment 1, the heat from the sensor board 19 and the signal transmission board 20 is efficiently released without heat transfer between them.

[0057] For example, the gap 22 is 5 mm, the length of the FPC 13 is 13 mm, and the diameters of the sensor board 19 and the signal transmitting board 20 are each 20 mm.

[0058] In the first embodiment, the sensor board 19 and the signal transmission board 20 are separated and are not configured as a single integrated board. The sensor board 19 is arranged coaxially with the signal transmission board 20 in the optical axis direction with a gap 22 between them. The in-plane directions of the sensor board 19 and the signal transmission board 20 are perpendicular to the optical axis direction. This allows for both improved heat dissipation efficiency and miniaturization of the camera head 2. Furthermore, the projection size of the camera head 2 from the shooting direction can be reduced.

[0059] Furthermore, the camera head 2 has the sensor board 19 and the signal transmission board 20 as separate boards arranged in the optical axis direction. This allows the diameter of the camera head 2 to be smaller when viewed in the optical axis direction than in a configuration where the boards are integrated into one. For example, the length of the camera head 2 in the optical axis direction is approximately 60 mm to 70 mm.

[0060] Next, details of the tip of the camera head 2 will be described. Fig. 9 is an exploded perspective view of the tip of the camera head 2. As shown in Fig. 9, the front case 9 has a cylindrical body 9c and a contact surface 9a with which the LED board 8 comes into contact. The contact surface 9a is provided at the front end of the body 9c in the optical axis direction.

[0061] The front case 9 has a heat sink 9b. The heat sink 9b has a plurality of fins 9d (fin portions) and a plurality of slits 9e (hole portions). The fins 9d and the slits 9e are provided intermittently on the circumferential surface of the body 9c. The fins 9d and the slits 9e each extend along the circumferential direction. The fins 9d and the slits 9e are each provided at four locations along the circumferential direction.

[0062] With this configuration, heat generated by the LED substrate 8 moves to the front case 9 via the contact surface 9a and is released via the heat sink 9b. Furthermore, the air inside the front case 9 is exchanged (ventilated) with air outside the front case 9 via the multiple slits 9e, preventing the lens unit 14 housed in the front case 9 from becoming too hot. Furthermore, because the front case 9 is connected to the lens unit case 15 via the heat insulating ring 10, heat from the LED substrate 8 is prevented from moving to the lens unit case 15. Furthermore, with this configuration, the axial length of the front case 9 can be shortened compared to a heat sink having fins extending along the optical axis direction.

[0063] Note that mesh or punched holes may be used instead of the slits 9e. That is, the heat sink 9b only needs to have holes, and slits, mesh, or punched holes may be used as appropriate as the holes. Furthermore, the slits, mesh, and punched holes may be used alone or in combination. The shapes of the slits, mesh, and punched holes are arbitrary. Furthermore, the heat sink 9b may be configured only with a plurality of slits 9e (holes) without providing a plurality of fins 9d as the fin portion.

[0064] The front case 9 houses a portion of the front of the lens unit case 15 and physically protects the lens unit 14. The lens unit case 15 has a thin-walled, cylindrical partition wall 15e that is disposed on the outer periphery of the lens unit 14 and completely surrounds the lens unit 14. The partition wall 15e is made of a metal material. The partition wall 15e is unpainted. This minimizes radiant heat transfer from the heat sink 9b. In other words, it is possible to suppress the transfer of heat from the heat sink 9b to the lens unit 14.

[0065] The partition wall 15e extends forward from the front end of the lens unit case 15. Specifically, the partition wall 15e extends from the front end of the lens unit case 15 to a position close enough to the front end of the lens unit case 15 but not to the inside of the contact surface 9a of the front case 9. This allows the air flow inside the front case 9 to be unimpeded and maintains a good heat dissipation effect. Furthermore, it is possible to prevent heat from the LED board 8 from transferring to the partition wall 15e. When the front case 9 is attached to the lens unit case 15, the partition wall 15e divides the annular space between the front case 9 and the lens unit 14 in the radial direction (a direction perpendicular to the optical axis direction), forming two air layers 15f and 15g, which will be described below.

[0066] FIG. 10 is an explanatory diagram of the air layers 15f and 15g in the front case 9, showing a portion of a vertical cross section of the tip of the camera head 2. As shown in FIG. 10 , when the lens unit 14 is housed in the lens unit case 15 and the front case 9 is attached to the lens unit case 15, an air layer 15f separated by a partition wall 15e is formed around the lens unit 14. Additionally, an air layer 15g separated by a heat sink 9b is formed around the partition wall 15e. In this way, two air layers 15g and 15f are interposed between the inner circumferential surface of the front case 9 and the lens unit 14, with the partition wall 15e interposed therebetween. Therefore, the insulating effect of the air layers 15g and 15f prevents heat from transferring from the heat sink 9b to the lens unit 14.

[0067] More specifically, heat generated by the LED board 8 transfers to the heat sink 9b via the contact surface 9a, but the air layers 15g and 15f prevent the heat from the LED board 8 from transferring to the lens unit 14. This suppresses temperature rise in the lens 18, preventing deterioration of the lens 18 (e.g., thermal deformation and focus shift due to thermal expansion). Furthermore, the thin-walled cylindrical partition 15e alone provides sufficient thermal insulation, preventing the diameter of the camera head 2 from increasing. In this way, the front case 9 dissipates heat generated by the LED board 8 into the surrounding atmosphere, preventing thermal damage to the lens unit 14 and the image sensor 19a. Furthermore, the front case 9 holds the LED board 8 in a position that prevents unwanted illumination light from leaking into the lens unit 14. In other words, the front case 9 of this embodiment achieves both suppression of lens 18 deterioration and miniaturization of the camera head 2.

[0068] Next, the LED board 8 will be described in detail. Fig. 11 is a front view of the LED board 8. As shown in Fig. 11, the LED board 8 has a plurality of light-emitting members, for example, four LEDs 8a. The LEDs 8a irradiate light to the outside through the LED cover 7. The size of the LEDs 8a is, for example, 1.6 mm x 2.0 mm.

[0069] A copper pattern 8c, which is a thin copper film, is provided on the mounting surface of the LED substrate 8 on which the LEDs 8a are mounted. The LED substrate 8 is a multi-layer substrate, each having a copper pattern 8c.

[0070] Heat from the LEDs 8a is released into the air inside the LED cover 7 via the copper pattern 8c, and is also transferred to the heat sink 9b via the contact surface 9a of the front case 9. The heat is then released to the outside of the camera head 2 (e.g., the atmosphere) via the heat sink 9b. With this configuration, the heat from the LEDs 8a is efficiently released to the outside of the camera head 2.

[0071] The LED substrate 8 has a connector mounting portion 8b that protrudes radially outward from the peripheral edge (for example, by 1.25 mm). The connector mounted on the connector mounting portion 8b is connected to a connector mounted on the LED driver substrate 21 via a lead wire (not shown).

[0072] The diameter of the LED board 8 is, for example, 24 mm. The width of the LED board 8 including the connector mounting portion 8b is, for example, 25.3 mm.

[0073] The four LEDs 8a are spaced apart from one another at positions that overlap (correspond to) the fins 9d and slits 9e of the heat sink 9b in the circumferential direction of the front case 9 when viewed from the optical axis direction. This allows the camera head 2 to efficiently release heat generated by the LEDs 8a from the heat sink 9b into the atmosphere. This allows the camera head 2 to prevent heat from the LED board 8 from transferring to the lens unit 14 and the image sensor 19a.

[0074] Next, the rear case 12 will be described in detail. FIG. 12 is a perspective view showing a vertical cross section of the camera head 2. As shown in FIG. 12, the rear case 12 is cylindrical. The rear case 12 has a heat sink 12a at the rear end of the outer circumferential surface of the rear case 12. The heat sink 12a has multiple fins 12f parallel to the optical axis direction. The fins 12f are arranged at equal intervals along the circumferential direction on the outer circumferential surface of the rear case 12. By forming the fins 12f parallel to the optical axis direction, heat from the rear case 12 can be efficiently dissipated. Note that the fins 12f do not protrude from the outer circumferential surface of the rear case 12 when viewed from the optical axis direction. In other words, when viewed from the optical axis direction, the diameter of a circle centered on the optical axis L and tangent to each apex of the multiple fins 12f is approximately the same as the diameter of the rear case 12.

[0075] Here, the orientation of the fins 12f does not have to be parallel to the optical axis direction. For example, the orientation of the fins 12f may be the circumferential direction of the rear case 12 or a direction intersecting the optical axis direction. Furthermore, the shape of the fins 12f is arbitrary. For example, the fins 12f may have a shape (pillar shape) that protrudes from the outer circumferential surface of the rear case 12.

[0076] The rear case 12 has a protrusion 12b on its inner circumferential surface extending toward the optical axis L. The protrusion 12b is a thick, annular stepped portion formed on the inner circumferential surface of the rear case 12. The protrusion 12b is provided at the rear end of the rear case 12. The protrusion 12b and the heat sink 12a are at approximately the same position in the optical axis direction, and the protrusion 12b is located on the inner circumferential side of the heat sink 12a. Therefore, heat transferred to the protrusion 12b can be released from the protrusion 12b via the heat sink 12a to the outside of the camera head 2 (e.g., the atmosphere). The heat sink 12a and the protrusion 12b are an example of a heat dissipation unit. The heat sink 12a has a shape that does not protrude from the outer periphery of the rear case 12, and the protrusion 12b is provided on the inner circumferential surface of the rear case 12. Therefore, the camera head 2 can release heat transferred to the rear case 12 to the atmosphere via the protrusion 12b and the heat sink 12a, thereby improving heat dissipation efficiency. Furthermore, by configuring the camera head 2 so that heat can be dissipated from the rear case 12, it is possible to reduce the overall size of the camera head 2. That is, the camera head 2 according to the first embodiment can achieve both improved heat dissipation efficiency and miniaturization.

[0077] The rear case 12 has a heat transfer section 26 therein that contacts the signal transmission board 20 and the protrusion 12b. The heat transfer section 26 has a shaft 23a, a metal member 24, and a heat transfer sheet 25, which will be described below.

[0078] A second spacer member 23 is provided between the signal transmission board 20 and the LED driver board 21 (see also FIGS. 4 to 7). The second spacer member 23 is made of an arc-shaped resin block, and is attached to the module mounting surface 20d of the signal transmission board 20. The second spacer member 23 contacts the LED driver board 21, maintaining the distance between the signal transmission board 20 and the LED driver board 21.

[0079] One end (front end) of a shaft 23a extending along the optical axis direction is attached to the second spacer member 23. A metal member 24 is attached to the other end (rear end) of the shaft 23a. Thus, the metal member 24 is fixed to a predetermined position in contact with the end surface 12e of the protrusion 12b via the second spacer member 23 and the shaft 23a from the signal transmission board 20. The metal member 24 is an L-shaped block. The metal member 24 is preferably made of a metal material with high thermal conductivity, and is made of aluminum in the first embodiment, for example.

[0080] The metal member 24 is in thermal contact with the components mounted on the LED driver board 21 via the heat transfer sheet 25 (see FIG. 8 ). The heat transfer sheet 25 is an insulating heat transfer member that is flexible and adhesive. Therefore, the heat transfer sheet 25 adheres to the metal member 24 and the components mounted on the LED driver board 21. Heat generated by the components mounted on the LED driver board 21 is efficiently transferred to the metal member 24 via the heat transfer sheet 25 and ultimately released to the outside of the camera head 2 (e.g., the atmosphere) via the protrusion 12b and the heat sink 12a. Therefore, the camera head 2 can efficiently dissipate heat via the rear case 12.

[0081] In this way, by providing the heat transfer section 26 inside the rear case 12, it is possible to improve the heat dissipation efficiency of the camera head 2. Furthermore, since the fins 12f do not protrude from the outer peripheral surface of the rear case 12 and no auxiliary heat transfer section such as a fan needs to be provided on the outer periphery of the rear case 12, the camera head 2 can be made smaller.

[0082] The second spacer member 23 has a positioning member 23b extending rearward in the optical axis direction (see FIG. 7). The positioning member 23b engages with the notch 21a of the LED driver board 21, and the positioning member 23b is fixed to the LED driver board 21. The positioning member 23b may be fixed to the LED driver board 21 by fixing the positioning member 23b to the notch 21a with an adhesive. This positions the LED driver board 21.

[0083] The rear case 12 has a female thread portion 12d (see FIG. 2) on the inner peripheral surface of its front portion. The lens unit case 15 has a male thread portion 15h (see FIG. 9). The rear case 12 is connected to the lens unit case 15 by threading the female thread portion 12d into the male thread portion 15h. Note that the method of connecting the rear case 12 and the lens unit case 15 is not limited to threading. Other connecting means, such as a cam mechanism or a slide mechanism, or a means of connecting the two by direct fitting may also be used.

[0084] When the rear case 12 is rotated (attached) relative to the lens unit case 15 while fitted into the lens unit case 15, the metal member 24 slides circumferentially while contacting the end surface 12e of the protrusion 12b. When the rear case 12 is completely attached to the lens unit case 15 until it no longer rotates relative to the lens unit case 15, the metal member 24 and the protrusion 12b are in thermal contact. In this way, the metal member 24 is configured to slide on the end surface 12e of the protrusion 12b, making it easier to assemble the camera head 2.

[0085] A waterproof cap 12c is attached to the rear end of the rear case 12. Waterproof rubber is provided inside the waterproof cap 12c. The cable 4 is inserted through this rubber. The rubber fixes the position of the cable 4 at the rear end of the rear case 12.

[0086] Next, the heat sources of the head-separated camera 1 will be described. FIG. 13 is an explanatory diagram showing the heat sources of the head-separated camera 1. As shown in FIG. 13, the lens unit 14 in the camera head 2 does not generate heat. The LED board 8 generates heat from the LEDs 8a, which are the main heat source. The LED board 8 generates a large amount of heat (heat generation: large). The sensor board 19 generates heat from the imaging element 19a, which is the main heat source. The sensor board 19 generates less heat than the LED board 8 (heat generation: medium). The LED driver board 21 generates heat from the power driver, which is the main heat source. The LED driver board 21 generates less heat than the LED board 8 (heat generation: medium). The signal transmission board 20 generates heat from the signal conversion circuit, which is the main heat source. The signal transmission board 20 generates less heat than the LED board 8 (heat generation: medium). The imaging element 19a is significantly affected by heat (e.g., noise). Therefore, the chip that serves as the heat source is mounted on the signal transmission board 20. The heat generation of the LEDs 8a varies depending on the illuminance of the LEDs 8a. Therefore, the magnitude relationship between the amount of heat generated by the imaging element 19a and the amount of heat generated by the LED 8a may be reversed.

[0087] In the camera control unit 3, the signal receiving board 31 generates heat from the signal conversion circuit, which is the main heat source. The amount of heat generated by the signal receiving board 31 is smaller than that of the LED board 8 (heat generation: medium). The control board 32, which performs image processing, generates heat from the SoC (System on a Chip), which is the main heat source. The amount of heat generated by the control board 32 is smaller than that of the LED board 8 (heat generation: medium). Note that the amount of heat generated by the LED 8a varies depending on the illuminance of the LED 8a. Therefore, the magnitude relationship between the amount of heat generated by the SoC and the amount of heat generated by the LED 8a may be reversed.

[0088] Next, heat transfer in the camera head 2 will be described. FIG. 14 is an explanatory diagram showing heat transfer in the camera head 2. As shown in FIG. 14, in the camera head 2, the heat source of the LED board 8 is the LED 8a. Heat from the LED board 8 is released into the air inside the LED cover 7 from the copper pattern 8c by convection and radiation. The heat from the LED board 8 then moves to the front case 9 and is released to the outside of the camera head 2 from the heat sink 9b (A in the figure). The heat from the LED board 8 is also reflected by the partition 15e via the air layer 15g. The heat reflected by the partition 15e is released from the heat sink 9b to the outside of the camera head 2 (the atmosphere) (B in the figure). The heat source of the sensor board 19 is the image sensor 19a. Heat from the sensor board 19 is released into the air inside the lens unit case 15 by convection and radiation from the copper pattern 19e. Furthermore, the heat of the sensor board 19 moves from the lens unit case 15 to the bracket 6 and is released to the outside of the camera head 2 (the atmosphere) (C in the figure).

[0089] The heat sources of the signal transmission board 20 are the Ser 20a, the DC / DC converter 20b, and the LDO regulator 20c. The heat of the signal transmission board 20 is released into the air inside the rear case 12 by convection and radiation from the copper pattern 20f, and is then released from the heat sink 12a to the outside (atmosphere) of the camera head 2 (D in the figure). Furthermore, the heat of the signal transmission board 20 moves via the cable 4 to the camera control unit 3, which is an external device, and is released from the camera control unit 3 to the atmosphere.

[0090] The power supply driver 21b is the heat source of the LED driver board 21. The heat of the LED driver board 21 is transferred to the protrusion 12b via the heat transfer sheet 25 and the metal member 24, and is then released to the outside (atmosphere) of the camera head 2 from the heat sink 12a by convection and radiation (point E in the figure).

[0091] In the camera control unit 3, the heat source of the signal receiving board 31 is a Des (Deserializer) 31a, and the heat source of the control board 32 is a Soc 32a. The heat of the signal receiving board 31 and the control board 32 is released into the atmosphere from the camera control unit 3 (F and G in the figure).

[0092] As described above, according to the first embodiment, it is possible to improve the heat dissipation effect and reduce the size of the camera head 2 at the same time.

[0093] [Embodiment 2] The present invention is not limited to the camera head 2 described in the above-mentioned embodiment 1, but can also be applied to a camera head 100 that does not have an LED board 8. The camera head 100 according to embodiment 2 is characterized in that it has a single housing 101 that houses the lens unit 14, sensor board 19, and signal transmission board 20, and in that it does not have an LED board 8 or LED cover 7. Therefore, the main features of the camera head 100 will be described below, and parts that are the same as those in embodiment 1 will be assigned the same reference numerals and will not be described again.

[0094] Fig. 15 is a longitudinal cross-sectional view of the camera head 100 according to embodiment 2. As shown in Fig. 15, the camera head 100 according to embodiment 2 has a cylindrical housing 101. The housing 101 houses the lens unit 14, the sensor board 19, and the signal transmission board 20. The housing 101 has a heat sink 112a at its rear end.

[0095] As in FIGS. 4 to 7 , the sensor board 19 and the signal transmission board 20 are held at a predetermined distance by the spacer member 15c and the positioning member 15d. The sensor mounting surface 19b of the sensor board 19 is in thermal contact with the housing 101. Specifically, the copper pattern 19e on the sensor mounting surface 19b is in physical contact with the housing 101. Meanwhile, the signal transmission board 20 is separated from the housing 101. As shown in FIG. 15 , the sensor board 19 is disposed approximately in the center of the housing 101 and divides the space within the housing 101 in the optical axis direction. Therefore, almost no air circulates within the housing 101 between the space within the housing 101 formed in front of the sensor board 19 and the space within the housing 101 formed behind the sensor board 19. In other words, the camera head 100 is configured such that heat generated behind the sensor board 19 is unlikely to move forward of the sensor board 19.

[0096] Next, heat transfer in the camera head 100 will be described. FIG. 16 is an explanatory diagram showing heat transfer in the camera head 100 according to the second embodiment. As shown in FIG. 16, heat from the sensor board 19 transfers to the housing 101 and is released from the housing 101 to the outside (atmosphere) of the camera head 100 (A in the figure). Heat is also released from the housing 101 to the outside (atmosphere) of the camera head 100 via the bracket 6. Heat from the signal transmission board 20 is released by radiation to the outside (atmosphere) of the camera head 100 via the heat sink 112a (B in the figure). Heat from the signal transmission board 20 transfers to the camera control unit 3, which is an external device, via the cable 4 and is released from the camera control unit 3 to the outside (atmosphere). Note that because the sensor board 19 divides the space within the housing 101 in the optical axis direction (see FIG. 15), almost no heat from the signal transmission board 20 transfers to the lens unit 14 or the image sensor 19a.

[0097] The heat generated by the signal receiving board 31 and the control board 32 is released into the atmosphere from the camera control unit 3 (F, G in the figure), as in the first embodiment.

[0098] In the second embodiment, the sensor board 19 and the signal transmission board 20 are not integrated into a single integrated board. The sensor board 19 and the signal transmission board 20 are aligned along the optical axis L. The in-plane direction of the sensor board 19 and the in-plane direction of the signal transmission board 20 are perpendicular to the optical axis direction. This configuration allows the camera head 100 to be miniaturized. The sensor board 19 and the signal transmission board 20 are arranged with a gap between them. This improves heat dissipation efficiency. Therefore, the camera head 100 according to the second embodiment can achieve both miniaturization and improved heat dissipation efficiency.

[0099] [Embodiment 3] Next, a camera head 200 according to embodiment 3 will be described. Like the camera head 100, the camera head 200 does not have the LED board 8 or the LED cover 7. However, the camera head 200 has a different housing structure from the camera head 100. Note that the same parts as those in embodiments 1 and 2 are denoted by the same reference numerals, and descriptions thereof will be omitted.

[0100] 17 is a longitudinal cross-sectional view of a camera head 200 according to the third embodiment. As shown in FIG. 17 , the camera head 200 includes an imaging unit 202, a front case 203 provided in front of the imaging unit 202, and a rear case 204 provided behind the imaging unit 202. The imaging unit 202 holds the rear portion of the lens unit 14 by screwing. The front case 203 is connected to the imaging unit 202 and houses the front portion of the lens unit 14, i.e., the portion exposed forward of the imaging unit 202. The rear case 204 houses the sensor board 19 and the signal transmission board 20. The housing 201 includes the front case 203, the imaging unit 202, and the rear case 204. The housing 201 is cylindrical overall.

[0101] The front case 203 is connected to the imaging unit 202 by a connection method that has high thermal resistance. The rear case 204 is connected to the imaging unit 202 by a connection method that has high thermal resistance. Connection methods that have high thermal resistance include, for example, a screw connection with a small contact area, a connection via a member with low thermal conductivity (e.g., resin), or a connection via an adhesive.

[0102] Either or both of the front case 203 and the rear case 204 are connected to an external member (for example, bracket 6). In other words, the camera head 200 is configured to allow heat to be transferred from the front case 203 and the rear case 204 to members external to the camera head 200. In addition, either or both of the front case 203 and the rear case 204 are provided with heat dissipation means (for example, heat sink 209b or heat sink 212a) for dissipating heat to the outside of the camera head 200 (for example, the atmosphere).

[0103] The sensor board 19 is held at a position spaced a predetermined distance from the signal transmitting board 20 by the spacer member 15c and the positioning member 15d, as in the cases of FIGS.

[0104] The sensor mounting surface 19b of the sensor board 19 is in contact with the housing 201 (specifically, the imaging unit 202) and is in thermal contact with it. On the other hand, the signal transmission board 20 is spaced apart from the housing 201.

[0105] Next, heat transfer in the camera head 200 will be described. FIG. 18 is an explanatory diagram showing heat transfer in the camera head 200 according to the third embodiment. As shown in FIG. 18, heat from the sensor board 19 is released to the outside (atmosphere) of the camera head 200 via the front case 203 (A in the figure). Heat from the signal transmission board 20 is released to the outside (atmosphere) of the camera head 200 via the rear case 204 (B in the figure). Heat from the signal transmission board 20 also moves via the cable 4 to the camera control unit 3, which is an external device, and is released to the outside (atmosphere) from the camera control unit 3. Heat from the signal receiving board 31 and the control board 32 is released to the atmosphere from the camera control unit 3, as in the first and second embodiments (F and G in the figure).

[0106] According to the third embodiment, in the camera head 200, similar to the first or second embodiment, it is possible to achieve both an improvement in the heat dissipation effect and a miniaturization of the camera.

[0107] [Variations] In the above embodiment, examples have been described in which the sensor substrate 19, the signal transmission substrate 20, and the LED driver substrate 21 are single-layer substrates, but any one or all of the sensor substrate 19, the signal transmission substrate 20, and the LED driver substrate 21 may be multi-layer substrates.

[0108] Fig. 19 shows a sensor substrate and a signal transmission substrate according to a modified example. For example, as shown in Fig. 19, a multi-layered sensor substrate 40 has a sensor mounting surface 40a. The substrate also has a heat dissipation layer 40b formed of a copper pattern made of copper foil. This increases thermal conductivity and enables efficient heat dissipation.

[0109] The multi-layered signal transmission board 41 has a module mounting surface 41a and a heat dissipation layer 41b formed of a copper pattern made of copper foil, which increases the thermal conductivity and allows for efficient heat dissipation.

[0110] Although various embodiments have been described above with reference to the drawings, it goes without saying that the present disclosure is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications, alterations, substitutions, additions, deletions, and equivalents within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present disclosure. Furthermore, the components of the various embodiments described above may be combined in any manner without departing from the spirit of the invention.

[0111] The present disclosure includes the following inventions:

[0112] (Invention 1A) An imaging device comprising: an imaging element; a lens unit that guides light to the imaging element; a front case that houses the lens unit; and a partition wall that extends along an optical axis direction in a space between the lens unit and the front case and radially divides the space.

[0113] (Invention 1B) The imaging device according to Invention 1A, further comprising a heat dissipation section provided on an outer peripheral surface of the front case, the heat dissipation section having at least one of fins and holes.

[0114] (Invention 1C) The imaging device according to Invention 1B, wherein the heat dissipation section has at least the hole portion, and the hole portion has at least one of a slit shape, a mesh shape, and a punch hole shape, and air inside the front case is ventilated through the hole portion.

[0115] (Invention 1D) The imaging device according to Invention 1A, further comprising a light source that illuminates a front side of the lens unit, the light source being in thermal contact with the front case.

[0116] (Invention 1E) The imaging device according to Invention 1D, wherein the light source includes a plurality of light-emitting elements, an element substrate on which the plurality of light-emitting elements are mounted, and a heat transfer pattern provided on the element substrate on a mounting surface of the plurality of light-emitting elements, the heat transfer pattern dissipating heat from the element substrate.

[0117] (Invention 1F) An imaging device as described in Invention 1E above, which has a heat dissipation section provided on the outer peripheral surface of the front case, and the front case has a contact surface with the heat transfer pattern at the end on the side where light is incident in the optical axis direction, and heat from the element substrate moves from the heat transfer pattern to the heat dissipation section via the contact surface.

[0118] (Invention 1G) The imaging device according to Invention 1F, further comprising a lens unit case that holds the lens unit, the front case and the lens unit case being connected via a heat insulating member.

[0119] (Invention 1H) The imaging device according to Invention 1C, wherein all of the holes have the slit shape, and the slit shape extends in the circumferential direction of the front case.

[0120] (Invention 1I) An imaging device as described in Invention 1A above, comprising a heat dissipation section provided on the outer peripheral surface of the front case and a light source that illuminates the area in front of the lens unit, the light source being in thermal contact with the front case, the heat dissipation section having a hole provided in the circumferential direction of the front case, and the light source having a light emitting section provided in a position that overlaps with the hole when the front case is viewed from the optical axis direction.

[0121] (Invention 1J) The imaging device according to Invention 1E, further comprising a drive substrate having a drive unit that drives the plurality of light-emitting elements, the drive substrate being provided downstream of the element substrate in the light traveling direction in the optical axis direction.

[0122] (Invention 1K) The imaging device according to Invention 1A, wherein the partition is a cylinder made of a metal material, and the surface of the partition is unpainted.

[0123] (Invention 2A) An imaging device comprising: an imaging element; a lens unit that guides light to the imaging element; a processing module that processes an output signal of the imaging element; and a housing that houses the imaging element, the lens unit, and the processing module, wherein the housing has a heat dissipation section that is provided downstream of the lens unit in the direction of travel of light from the lens unit toward the imaging element, the heat dissipation section including a plurality of fins provided on the outer peripheral surface of the housing and a protrusion provided on the inner peripheral surface of the housing, and the processing module is in thermal contact with the protrusion.

[0124] (Invention 2B) The imaging device according to Invention 2A, wherein the processing module is disposed downstream of the imaging element in the traveling direction of the light.

[0125] (Invention 2C) The imaging device according to Invention 2B, wherein the processing module is in thermal contact with the protrusion via a heat transfer part.

[0126] (Invention 2D) The imaging device according to Invention 2C, wherein the housing includes a lens unit case that houses the lens unit, and a rear case that houses the imaging element and the processing module, and the heat transfer part is slidable along the protrusion when the rear case is attached to the lens unit case.

[0127] (Invention 2E) The imaging device according to Invention 2D, wherein the lens unit case is screwed to the rear case, and the heat transfer portion is slidable in a circumferential direction with respect to the protrusion when the lens unit rotates relative to the rear case.

[0128] (Invention 2F) The imaging device according to Invention 2E, wherein the heat transfer section includes a metal member that slides on the protrusion, and an insulating heat transfer member that contacts the processing module.

[0129] (Invention 2G) The imaging device according to Invention 2A, wherein the processing module is connected to an external device via a cable.

[0130] (Invention 2H) The imaging device according to Invention 2A, wherein the housing is cylindrical overall, and the plurality of fins are shaped so as not to protrude from the outer circumferential surface of the housing when viewed in the optical axis direction.

[0131] (Invention 2I) The imaging device according to Invention 2A, wherein the plurality of fins each have at least one of a shape extending parallel to the optical axis direction and a shape extending in a direction intersecting the optical axis direction.

[0132] The present disclosure is useful as an imaging device that achieves both improved heat dissipation efficiency and miniaturization.

[0133] DESCRIPTION OF SYMBOLS 2 Camera head (imaging device) 3 Camera control unit (external device) 4 Cable 5 Housing 6 Bracket 7 LED cover 8 LED board (element board) 8a LED (light-emitting element) 8c Copper pattern (heat transfer pattern) 9 Front case (housing) 9a Contact surface 9b Heat sink 10 Heat insulating ring (heat insulating member) 11 Imaging unit 12 Rear case (housing) 12a Heat sink (heat dissipation section) 12b Protrusion 12d Fin 13 FPC (flexible conductive member) 14 Lens unit 15 Lens unit case (housing) 15c Spacer member 15d Positioning member 15e Partition 15g, 15g Air layer 19 Sensor board (first board) 19a Imaging element 19b Sensor mounting surface (first mounting surface) 19c Notch (first notch section) 19d Notch (second notch portion) 19e Copper pattern (heat transfer pattern) 20 Signal output board (second board) 20a Ser (processing module) 20b DC / DC converter (processing module) 20c LDO regulator (processing module) 20d Module mounting surface (second mounting surface) 20e Notch (third notch portion) 20f Copper pattern (heat transfer pattern) 21 LED drive board (drive board) 23 Second spacer member 23a Shaft portion 24 Metal member 25 Heat transfer sheet (heat transfer member) L Optical axis

Claims

1. a first substrate having a first mounting surface on which an imaging element is mounted; a second substrate having a second mounting surface on which a processing module for processing an output signal from the imaging element is mounted; a lens unit that guides light to the imaging element; a housing that houses the first substrate, the second substrate, and the lens unit, the first substrate is disposed so that the first mounting surface intersects with the optical axis direction, the second substrate is disposed so that the second mounting surface intersects with the optical axis direction and so that a gap is formed between the second substrate and the first substrate along the optical axis direction; The gap is maintained by a spacer member. Imaging device.

2. the first substrate has a heat transfer pattern that dissipates heat generated on the first mounting surface; The imaging device according to claim 1 .

3. the heat transfer pattern is provided around the imaging element on the first mounting surface; The imaging device according to claim 2 .

4. the housing includes a lens unit case that holds the lens unit; the lens unit case is in thermal contact with the first mounting surface; The imaging device according to claim 1 .

5. a flexible conductive member connecting the first substrate and the second substrate; The imaging device according to claim 1 .

6. The amount of heat generated by the second substrate is greater than the amount of heat generated by the first substrate. The imaging device according to claim 1 .

7. the processing module has a function of converting a parallel signal from the image sensor into a serial signal and transmitting the serial signal; The imaging device according to claim 1 .

8. A cable is provided for outputting a signal to an external device, the cable is connected to the second board; The heat of the second substrate is dissipated to the outside through the cable. The imaging device according to claim 1 .

9. the second mounting surface has a connection port for the cable and a heat transfer pattern provided around the connection port for dissipating heat generated on the second mounting surface. The imaging device according to claim 8 .

10. The spacer member maintains the gap by abutting against a surface of the second substrate opposite to the second mounting surface. The imaging device according to claim 1 .

11. The first substrate and the second substrate are disk-shaped. The imaging device according to claim 10.

12. one end of the spacer member engages with a first notch provided in a peripheral edge portion of the first substrate, and the other end abuts against the second substrate; The imaging device according to claim 11.

13. a positioning member for positioning the second substrate relative to the first substrate in a circumferential direction, the positioning member engages with a second notch provided in a peripheral edge portion of the first substrate and a third notch provided in a peripheral edge portion of the second substrate; The imaging device according to claim 12.

14. a bracket for holding the housing; The bracket is in thermal contact with the housing. The imaging device according to claim 1 .

15. The first substrate and the second substrate are arranged such that a surface of the first substrate opposite to the first mounting surface faces a surface of the second substrate opposite to the second mounting surface. The imaging device according to claim 1 .

16. The spacer member engages with the first substrate to restrict rotation of the first substrate around the optical axis direction. The imaging device according to claim 1 .