Optical unit and imaging device

Abstract

To provide an imaging apparatus which can discharge heat from a heat generation source to the outside by a simple and inexpensive structure.SOLUTION: An imaging apparatus 1 includes: an imaging element 16; an LED 10; a circuit board 20 with the imaging element 16 and the LED 10 equipped thereto; a heat discharge shield member 30 thermally in contact with the circuit board 20; and a housing for containing the circuit board 20 and the heat discharge shield member 30 in a container storage formed inside. The housing 2 has an opening 51 leading to the outside from the container space. The heat discharge shield member 30 includes a plate-like part 71 extending to close the opening 50 of the housing 20 and being exposed from the opening 50.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an optical unit and an imaging device, and particularly to an imaging device including an image pickup element.

Background Art

[0002] Generally, an optical unit constituting an imaging device or the like includes a heat source, and it is required to efficiently release the heat generated by this heat source to the outside. For this reason, for example, it is also conceivable to integrally mold a heat transfer member on the inner wall of the housing of the imaging device, and transmit the heat generated by the heat source through this heat transfer member to a terminal for image signal transmission to dissipate heat (see, for example, Patent Document 1). However, in such a conventional structure, since it is necessary to integrally mold a heat transfer member on the inner wall of the housing, the structure tends to become complicated, and its manufacturing cost also tends to increase.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention has been made in view of such problems of the prior art, and an object thereof is to provide an optical unit and an imaging device that can release heat from a heat source to the outside with a simple and inexpensive configuration.

Means for Solving the Problems

[0005] According to a first aspect of the present invention, there is provided an optical unit that can release heat from a heat source to the outside with a simple and inexpensive configuration. This optical unit includes at least one optical component including a heat source, a circuit board on which the at least one optical component is mounted, and configured to be in thermal contact with the circuit board Heat dissipation shielding memberAnd, in the housing space formed inside, the above-mentioned at least one optical component, the circuit board, and the Heat dissipation shielding member The housing comprises a housing for accommodating the above. The housing has at least one opening that communicates with the outside from the accommodating space. Heat dissipation shielding member It includes a plate-like portion that extends to close the at least one opening of the housing and is exposed to the outside through the at least one opening. The heat dissipation shield member is made of a conductive material and is configured to be electrically connected to the ground portion of the circuit board. The entire heat dissipation shield member is housed inside the housing.

[0006] According to a second aspect of the present invention, an imaging device comprising the optical unit described above is provided. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a front perspective view showing an imaging device as an optical unit in one embodiment of the present invention. [Figure 2] Figure 2 is a rear perspective view of the imaging device shown in Figure 1. [Figure 3] Figure 3 is an exploded perspective view of the imaging device shown in Figure 1. [Figure 4] Figure 4 is an exploded perspective view of the imaging device shown in Figure 2. [Figure 5] Figure 5 is an exploded perspective view of a part of the imaging device shown in Figure 4. [Figure 6] Figure 6 is a longitudinal cross-sectional view of the imaging device shown in Figure 1. [Modes for carrying out the invention]

[0008] Hereinafter, embodiments of the imaging device as an optical unit according to the present invention will be described in detail with reference to Figures 1 to 6. In Figures 1 to 6, identical or corresponding components are denoted by the same reference numerals, and redundant descriptions are omitted. Also, in Figures 1 to 6, the scale and dimensions of each component may be exaggerated, or some components may be omitted. In the following description, unless otherwise specified, terms such as "first" and "second" are used only to distinguish components from one another and do not represent a specific rank or order.

[0009] Figure 1 is a front perspective view showing an imaging device 1 as an optical unit in one embodiment of the present invention, and Figure 2 is a rear perspective view. In this embodiment, the imaging device 1 is described as an imaging device used in a driver monitoring system (DMS) that monitors the condition of a car driver (such as decreased attention or signs of drowsiness), but it goes without saying that the imaging device according to the present invention can be used for other purposes as well.

[0010] As shown in Figures 1 and 2, the imaging device 1 includes a rectangular housing 2 and a cover member 3 attached to the front of the housing 2. In Figure 1, the cover member 3 is omitted for ease of understanding. Inside the housing 2 are, for example, two LEDs (light-emitting diodes) 10 as light sources that emit near-infrared light, and a lens barrel 14 that holds at least one lens 12 inside. The housing 2 also has a mounting portion 7 for attaching the imaging device 1 to, for example, the body of an automobile. In this embodiment, for convenience, the +Z direction in Figure 1 is referred to as "front" or "forward," and the -Z direction is referred to as "rear" or "backward."

[0011] Figures 3 and 4 are exploded perspective views of the imaging device 1. As shown in Figures 3 and 4, the cover member 3 has a plurality of engaging pieces 31 that extend in the -Z direction and are elastically deformable in the Y direction, and each engaging piece 31 has a rectangular engaging hole 32 formed therein. The housing 2 has a plurality of claw portions 5 formed therein corresponding to the engaging pieces 31 of the cover member 3, and the cover member 3 is attached to the housing 2 by engaging these claw portions 5 with the engaging holes 32 of the engaging pieces 31 of the cover member 3.

[0012] The housing space formed inside the housing 2 houses a circuit board 20 on which the LED 10 and image sensor 16 are mounted, and a heat dissipation shield member 30 formed by bending a plate-shaped member. The circuit board 20 extends in the X direction as a whole, and a connector 21 is attached to the rear surface of the circuit board 20. The circuit board 20 has through holes 24 through which screws 42 are inserted, and the circuit board 20 is fixed to the housing 2 by inserting the screws 42 through these through holes 24 and screwing them into screw holes 6 formed in the housing 2.

[0013] The image sensor 16 is positioned on the plane through which light passing through the lens 12 of the lens barrel 14 forms an image, and is configured to receive light that has passed through the lens 12. The circuit board 20 has an insertion hole 22 through which a screw 41 is inserted, and a positioning hole 23 into which a positioning projection 15 formed on the lens barrel 14 is inserted. By inserting the positioning projection 15 of the lens barrel 14 into the positioning hole 23 of the circuit board 20, the lens barrel 14 is positioned relative to the circuit board 20, and by inserting the screw 41 into the insertion hole 22 of the circuit board 20 and screwing this screw 41 into a screw hole 17 formed on the lens barrel 14, the lens barrel 14 is fixed to the circuit board 20.

[0014] The cover member 3 is formed from a material that transmits light emitted from the LED 10. In this embodiment, since the LED 10 emits near-infrared light and the image sensor 16 acquires an image of near-infrared light, a visible light cut filter that cuts out light in the visible light wavelength range can be used as the cover member 3 to reduce the influence of visible light on the image obtained by the image sensor 16.

[0015] Multiple openings (circular openings in this embodiment) 51 are formed on the rear surface of the housing 2. The housing 2 also has a cylindrical connector connection portion 4 that extends rearward (-Z direction). The connector 21 of the circuit board 20 described above is inserted into and housed inside this connector connection portion 4. A mating connector (not shown) can be connected to this connector connection portion 4 from the rear of the housing 2. When the connector 21 and the mating connector are connected in this connector connection portion 4, the signal obtained by the image sensor 16 is output to the outside, and a control signal is input to the LED 10 from the outside. With this configuration, the LED 10 emits light (illumination light) to illuminate the object to be photographed (e.g., the driver), and the object illuminated by this light can be photographed by the image sensor 16.

[0016] The heat dissipation shield member 30 has a plate-shaped portion 71 extending along the XY plane and a side piece 72 extending in the +Z direction from the peripheral edge of the plate-shaped portion 71. The plate-shaped portion 71 has an insertion hole 73 for inserting the connector 21 extending from the circuit board 20 described above. The plate-shaped portion 71 extends to cover the opening 51 of the housing 2, and its size is approximately the same as the size of the circuit board 20. Preferably, the heat dissipation shield member 30 is made of a material with high thermal conductivity and electrical conductivity (for example, a metal such as copper, aluminum, or nickel).

[0017] Here, as shown in Figure 5, a pattern portion 25 made of copper foil or the like is formed on the back surface of the circuit board 20, and an elastically deformable spring member 60 (elastic connector) is attached to this pattern portion 25. The pattern portion 25 of the circuit board 20 is electrically connected to the electrical components mounted on the circuit board 20 and the ground portion of the connector 21. The spring member 60 is preferably made of a material with high thermal conductivity and conductivity (for example, a metal such as copper, aluminum, or nickel), similar to the heat shield member 30. The spring member 60 is fixed to the pattern portion 25 of the circuit board 20, for example, with solder.

[0018] FIG. 6 is a longitudinal sectional view of the imaging device 1. As shown in FIGS. 5 and 6, the spring member 60 includes a top portion 61 that contacts the plate-like portion 71 of the heat radiation shield member 30, a fixing portion 62 that is connected and fixed to the pattern portion 25 of the circuit board 20, an intermediate portion 63 that extends parallel to the top portion 61 and the fixing portion 62 between the top portion 61 and the fixing portion 62, and curved portions 64 that connect between the top portion 61 and the intermediate portion 63 and between the intermediate portion 63 and the fixing portion 62, respectively, and has a cross-section curved in a substantially S shape. With such a configuration, the spring member 60 can be elastically deformed in the Z direction, and the top portion 61 of the spring member 60 elastically contacts the plate-like portion 71 of the heat radiation shield member 30. With such a spring member 60, the pattern portion 25 of the circuit board 20 and the plate-like portion 71 of the heat radiation shield member 30 are thermally and electrically connected to each other. Thus, in the present embodiment, the spring member 60 and the heat radiation shield member 30 serve as contact portions that are in thermal contact with the circuit board 20.

[0019] In this imaging device 1, the imaging element 16 and the LED 10 housed in the housing space within the housing 2 can be heat sources. For example, if the imaging element 16 exceeds the junction temperature due to the heat generated by the LED 10 or the heat generated by the imaging element 16, the imaging element 16 will not operate properly. According to the present embodiment, the heat generated by the LED 10 and the imaging element 16 on the circuit board 20 is transmitted to the plate-like portion 71 of the heat radiation shield member 30 via the spring member 60, and this heat is released to the outside through the portion exposed from the opening 51 of the housing 2. Since the heat from the heat source on the circuit board 20 is efficiently released to the outside in this way, it is possible to suppress the optical components such as the imaging element 16 from becoming hot and causing malfunction.

[0020] Further, since the plate-like portion 71 of the heat radiation shield member 30 extends so as to close the opening 51 of the housing 2, the entry of external light into the housing 2 from the opening 51 of the housing 2 is suppressed. Therefore, the influence of the external light of the imaging device 1 on the imaging element 16 within the housing 2 can be reduced.

[0021] Furthermore, by forming the spring member 60 and heat shield member 30 constituting the contact portion described above from a conductive material, and by electrically connecting the spring member 60 to the pattern portion 25 of the circuit board 20, the spring member 60 and heat shield member 30 can be brought to the same potential as the ground portion of the circuit board 20. As a result, an electromagnetic shielding effect is generated in the spring member 60 and heat shield member 30, which can effectively protect the image sensor 16, LED 10, and other electronic components on the circuit board 20 housed in the housing space inside the housing 2 from electromagnetic noise.

[0022] In this embodiment, the heat dissipation shield member 30 has side pieces 72 that extend from the peripheral edge of the plate-shaped portion 71 toward the circuit board 20 (in the +Z direction), so that the area surrounded by these side pieces 72 can also be protected from electromagnetic noise.

[0023] Furthermore, in this embodiment, since the circuit board 20 and the plate-shaped portion 71 of the heat shield member 30 are connected by an elastically deformable spring member 60, even if the distance between the circuit board 20 and the plate-shaped portion 71 of the heat shield member 30 changes slightly due to manufacturing tolerances, the spring member 60 will elastically deform, thereby ensuring a more reliable connection between the circuit board 20 and the plate-shaped portion 71 of the heat shield member 30.

[0024] In this embodiment, an imaging device 1 in which an image sensor 16 and an LED 10 are mounted on a circuit board 20 was described as an example. However, the present invention is not limited to imaging devices and can be applied to any optical unit that has at least one optical component including a heat source. Furthermore, not only the image sensor 16 and LED 10 mentioned above, but also the power control unit and serializer can be heat sources.

[0025] Furthermore, while the number of openings 51 formed in the housing 2 is not particularly limited as long as there is one or more, in order to maximize heat dissipation from the heat source on the circuit board 20, it is preferable to form one or more openings 51 such that the opening area is as large as possible while maintaining the strength of the housing 2.

[0026] As described above, according to a first aspect of the present invention, an optical unit is provided that can dissipate heat from a heat source to the outside with a simple and inexpensive configuration. This optical unit comprises at least one optical component including a heat source, a circuit board on which the at least one optical component is mounted, a contact portion configured to thermally contact the circuit board, and a housing that houses the at least one optical component, the circuit board, and the contact portion in a housing space formed inside. The housing has at least one opening that communicates with the outside from the housing space. The contact portion includes a plate-like portion that extends to close the at least one opening of the housing and is exposed to the outside from the at least one opening.

[0027] With this configuration, the plate-shaped portion of the contact area is exposed to the outside through the opening of the housing, allowing heat generated by the heat source mounted on the circuit board to be transferred to the contact area and released to the outside through the exposed portion of the plate-shaped portion of the contact area. This prevents optical components from overheating and causing malfunctions. Furthermore, since the plate-shaped portion of the contact area extends to cover the opening of the housing, external light entering the housing through the opening is suppressed. This reduces the impact of external light on the optical components inside the housing.

[0028] Preferably, the contact portion is formed of a conductive material and configured to be electrically connected to the ground portion of the circuit board. In this case, since the contact portion is at the same potential as the ground portion of the circuit board, the electronic components on the circuit board housed in the housing space inside the housing can be effectively protected from electromagnetic noise.

[0029] Preferably, the contact portion further includes a side piece extending from the peripheral edge of the plate-like portion toward the circuit board. By forming such a side piece, the area surrounded by the side piece can also be protected from electromagnetic noise, thereby expanding the area protected from electromagnetic noise.

[0030] The contact portion may further include an elastically deformable elastic connecting portion that connects the circuit board and the plate-shaped portion. By using such an elastic connecting portion, even if the distance between the circuit board and the plate-shaped portion of the contact portion changes slightly due to manufacturing tolerances, the elastic connecting portion of the contact portion will elastically deform, thereby ensuring a more reliable connection between the circuit board and the plate-shaped portion of the contact portion.

[0031] The above-mentioned at least one optical component may include at least one of an image sensor, a light-emitting diode, a power supply control unit, and a serializer.

[0032] According to a second aspect of the present invention, an imaging device comprising the optical unit described above is provided.

[0033] Although preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to the embodiments described above and may be implemented in various different forms within the scope of its technical concept. [Explanation of symbols]

[0034] 1. Imaging device (optical unit) 2 Housing 3 Cover component 4. Connector connection section 10 LED 12 lenses 14 Lens barrel 16 Image sensor 20 Circuit boards 21 Connectors 25 Pattern section 30 Heat dissipation shield member (contact part) 31 Engaging piece 51 Aperture 60 Spring component (elastic connecting part) 61 Top 62 Fixed part 63 Middle section 64 Curved section 71 Plate-like part 72 side piece

Claims

1. At least one optical component including a heat source, A circuit board on which at least one optical component is mounted, A heat dissipation shield member configured to be in thermal contact with the circuit board, A housing that houses the at least one optical component, the circuit board, and the heat dissipation shield member in a housing space formed inside, wherein the housing has at least one opening that communicates with the outside from the housing space. Equipped with, The heat dissipation shield member includes a plate-like portion that extends to close the at least one opening of the housing and is exposed to the outside through the at least one opening. The heat dissipation shield member is formed of a conductive material and is configured to be electrically connected to the ground portion of the circuit board. The entire heat dissipation shield member is housed inside the housing. Optical unit.

2. The optical unit according to claim 1, wherein the heat dissipation shielding member further includes a side piece extending from the peripheral edge of the plate-shaped portion toward the circuit board.

3. The optical unit according to claim 1 or 2, further comprising an elastically deformable elastic connecting portion that thermally connects the circuit board and the plate-shaped portion.

4. The optical unit according to any one of claims 1 to 3, wherein the at least one optical component includes at least one of a light-emitting diode and a power supply control unit.

5. The optical unit according to any one of claims 1 to 4, wherein the at least one optical component includes an image sensor.

6. An imaging device comprising the optical unit described in claim 5.

Images