JP7503926B2 - Imaging device - Google Patents

Description

The present invention relates to an imaging device.

In recent years, with the improvement in the performance of image sensors, imaging devices are being used in a variety of fields. In particular, high-performance imaging devices are being used in vehicles not only to acquire images inside and outside the vehicle for safety and security measures (such as drive recorders), but also as cameras for digital mirrors and authentication cameras.

Imaging devices that use high-performance image sensors with a large number of pixels inevitably consume more power and generate more heat from their electronic components, but as imaging devices become more compact, the heat dissipation area becomes smaller, so heat dissipation measures for the driving electronic components are essential to maintain the performance of the image sensor. In particular, imaging devices for vehicles are in high demand for miniaturization and are forced to be used in high-temperature environments, so the heat dissipation measures mentioned above are particularly important.

To prevent heat dissipation from electronic components in imaging devices, the board on which the image sensor is mounted and the board on which electronic components that generate a large amount of heat during operation (such as a field-programmable gate array (FPGA)) are fixed) are mounted on separate boards, and the boards are arranged facing each other while being spatially separated.

The prior art described in Patent Document 1 below shows that in an imaging device, an FPGA board to which an FPGA is fixed, a connector board to which a connector that electrically connects to an external device is fixed, and a sensor board to which an image sensor is mounted are arranged face-to-face within the housing of the imaging device, the FPGA board and the connector board are connected by a first flexible board, and the connector board and the sensor board are connected by a second flexible board, and the FPGA, which is a heat source, is abutted against the inner wall of the housing to dissipate heat.

JP 2010-74665 A

In the conventional technology described above, a flexible board is used to connect the opposing boards, so the connection between the flexible board and the rigid board arranged opposite it must be performed separately from the assembly process, which creates a problem of complicating the work associated with assembly. In addition, space is required within the housing to handle the flexible board, and a relatively large space must be provided between the boards arranged opposite each other due to the flexible board, so the space required inside the housing increases, making it difficult to accommodate the miniaturization of the imaging device.

One solution to this problem is to use a board-to-board (B to B) connector to connect boards placed face-to-face. However, the board on which the image sensor is mounted has the image sensor located in the center of the board, and in consideration of the connection with the image sensor, electronic components that occupy a large area are also located in the center on the back side of the board on which the image sensor is mounted, so it becomes necessary to place the board-to-board connector near the periphery of the board.

When a board-to-board connector is placed near the edge of a board, if force is applied away from where the connector is located, the board will tilt and the connector will easily become dislodged. To avoid this, it is necessary to place a spacer between the opposing boards to prevent dislodgment, but providing a spacer reduces the mounting space for electronic components on the board surface and creates the problem of increased costs due to the addition of components.

When using board-to-board connectors, it is possible to save space compared to using flexible boards as in the conventional technology mentioned above, but the distance between the facing boards will be shorter, so effective heat dissipation measures will be necessary.

The present invention has been proposed to address these problems. In other words, the objective of the present invention is to use a board-to-board connector in the circuit board configuration of an imaging device to save space inside the housing and reduce the size of the device, and to provide more effective heat dissipation measures while preventing detachment without providing a spacer between boards arranged facing each other.

To solve these problems, the present invention has the following features:

a housing in which the lens unit is supported;
an imaging device comprising: a first substrate supported within the housing and having an image sensor mounted thereon, the image sensor having a light receiving surface that is the imaging surface of a lens unit; a second substrate connected to the first substrate by a substrate-to-substrate connector provided within the housing near a peripheral portion thereof; and a metal plate arranged within the housing so as to surround at least the second substrate, the metal plate having a support piece formed by bending a portion of the metal plate inward at a position away from the substrate-to-substrate connector so as to support the surface of the second substrate facing the first substrate.

FIG. 1 is an external perspective view of an imaging apparatus. FIG. FIG. FIG. 5 is a cross-sectional view taken along line AA in FIG. 4 . 5 is a cross-sectional view taken along the line B-B in FIG. 4 . FIG. 1 is an explanatory diagram of a metal plate ((a) is a plan view, and (b) is a side view). FIG. 4 is an explanatory diagram showing a metal plate contact piece. FIG. 1 is an explanatory diagram (plan view) of a vehicle equipped with an imaging device.

Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same reference numerals in different drawings indicate parts with the same function, and duplicate descriptions in each drawing will be omitted as appropriate.

As shown in Figures 1 to 6, the imaging device 1 includes at least a lens unit 2, a housing 3, a first substrate 11, a second substrate 12, and a metal plate 5.

The lens unit 2 is an imaging optical system that forms an image on the light receiving surface of the image sensor 10 mounted on the first substrate 11. The housing 3 supports the lens unit 2 and houses the first substrate 11, the second substrate 12, and the metal plate 5 inside. The lens unit 2 is attached to the housing 3 via a seal ring 8, and the rear housing 4 is connected to the rear of the housing 3 via the seal ring 8.

The first board 11 supported within the housing 3 has an image sensor 10 mounted on the surface facing the lens unit 2. The image sensor 10 is attached to the center of the first board 11, and uses the imaging surface of the lens unit 2 as its light receiving surface. Various electronic components connected to the image sensor 10 are attached to the back side of the first board.

The second board 12 arranged in the housing 3 has electronic components that constitute the drive circuit of the image sensor 10 attached thereto, and is disposed opposite the first board 11. The second board 12 is connected to the first board 11 by a board-to-board connector 20. Note that the "board-to-board connector" is sometimes simply called a "connector."

The board-to-board connector 20 has its female terminals attached near the periphery of the second board 12, and its male connector terminals 21 that connect to it are attached near the periphery of the first board 11. Various electronic components are attached to the front side of the second board 12 that faces the first board 11, and various electronic components are also attached to the back side of the second board 12.

Inside the housing 3, a metal plate 5 is arranged along the inner wall so as to surround at least the periphery of the second substrate 12. In the illustrated example, the metal plate 5 is arranged so as to surround both the first substrate 11 and the second substrate 12, and is configured to function as a shield plate.

In the illustrated example, the first substrate 11 and the second substrate 12 both have a polygonal shape (octagonal shape) in a planar view, and the metal plate 5 arranged around them is a band-shaped refracting plate having refracting portions 5B corresponding to the peripheral corners of the first substrate 11 or the second substrate 12, as shown in FIG. 7, and has multiple sides 5C between the refracting portions 5B.

In such an imaging device 1, the first board 11 on which the image sensor 10 is mounted is positioned and supported by the housing 3 so that the light receiving surface of the image sensor 10 becomes the imaging surface of the lens unit 2. In contrast, the second board 12 connected to the first board 11 via the board-to-board connector 20 is supported by a support piece 5A of the metal plate 5 so that the portion away from the board-to-board connector 20 does not approach the first board 11. The metal plate 5 is formed into a polygonal shape in a plan view by bending a single plate. However, in other embodiments, the metal plate 5 may be formed by forming a cylinder that is polygonal in a plan view and slicing it into rings.

The support piece 5A is formed by bending a part of the metal plate 5 inward at a position away from the board-to-board connector 20 so as to support the surface of the second board 12 facing the first board 11. In the example shown in FIG. 7, the support piece 5A is formed on three sides 5C, and the board-to-board connector 20 is located near the side 5C that does not have the support piece 5A.

More specifically, in the example shown in FIG. 7, one support piece 5A is provided on the side 5C facing the side 5C near the board-to-board connector 20, and a pair of support pieces 5A are provided on the sides 5C facing each other in a different direction.

By providing such a support piece 5A, the second board 12 connected to the first board 11 by the board-to-board connector 20 is prevented from tilting toward the first board 11, so that the board-to-board connector 20 can be prevented from coming off without providing a spacer to prevent it from coming off between the first board 11 and the second board 12. Furthermore, since the above-mentioned spacer to prevent it from coming off is not provided, the area of the back side of the first board 11 and the front side of the second board 12 can be effectively used to arrange electronic components. Moreover, instead of providing a spacer, the support piece 5A is formed by processing the metal plate 5 that functions as a shield plate, so that the board-to-board connector 20 can be prevented from coming off inexpensively without increasing the number of parts.

The imaging device 1 has a heat dissipation sheet 6 between the first substrate 11 and the second substrate 12 as a heat dissipation measure. The heat dissipation sheet 6 is an elastic member with high heat dissipation properties (such as a silicon resin plate), and is arranged so that the electronic components on the back side of the first substrate 11 and the electronic components on the front side of the second substrate 12 come into contact with each other by connecting the first substrate 11 and the second substrate 12 with a substrate-to-substrate connector 20. As shown in FIG. 5, the end of the heat dissipation sheet 6 is supported by being sandwiched between the support piece 5A of the metal plate 5 and the second substrate 12.

When such a heat dissipation sheet 6 is placed between the first board 11 and the second board 12, even if the first board 11 and the second board 12 are in close proximity, the heat generated by the electronic components can be transferred to the metal plate 5 via the heat dissipation sheet 6, and can be dissipated to the surroundings of the housing 3 via the metal plate 5.

At this time, the metal plate 5 is provided with contact pieces 5D that protrude elastically around the periphery, and as shown in FIG. 8, these contact pieces 5D come into contact with the inner wall of the housing 3 around the metal plate 5 while being elastically pressed against it. This allows the heat transferred to the metal plate 5 to be efficiently dissipated to the surroundings.

In this type of imaging device 1, the circuit board configuration first includes a first board 11 and a second board 12 connected via a board-to-board connector 20, which allows the imaging device 1 to be made smaller by narrowing the space between the boards to save space. In this case, the metal plate 5, which functions as a shield plate, is used to support the second board 12, preventing the board-to-board connector 20 from coming loose, allowing for a highly reliable electrical connection without increasing the number of parts. Furthermore, by not using a spacer, the board surfaces of the first board 11 and the second board 12 can be effectively used to arrange electronic components.

The heat dissipation sheet 6 is placed between the first board 11 and the second board 12, and its end is in contact with the support piece 5A of the metal plate 5. This makes it possible to obtain an effective heat dissipation effect even when the space between the boards is narrow. Furthermore, this heat dissipation sheet 6 essentially functions as a spacer between the boards, so in addition to improving the heat dissipation effect, it is also possible to improve the reliability of the connection of the board-to-board connector 20.

As a result, the imaging device 1 according to the embodiment of the present invention can achieve space saving inside the housing 3 and miniaturization of the device by using the board-to-board connector 20, and furthermore, can achieve more effective heat dissipation measures while improving the reliability of the connection in the board-to-board connector 20.

Figure 9 shows a vehicle 100 that uses the imaging device 1 described above as a side camera 101 and a rear camera 102. Such a vehicle 100 can acquire images of the surroundings of the vehicle 100 using the imaging device 1 that is high-performance and has effective heat dissipation measures. By using the imaging device 1, the vehicle 100 can ensure high safety and good driving operability.

Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configuration is not limited to these embodiments, and the present invention includes design changes and the like that do not deviate from the gist of the present invention. In addition, the above-mentioned embodiments can be combined by reusing each other's technologies, as long as there are no particular contradictions or problems in the purpose, configuration, etc.

1: imaging device, 2: lens unit, 3: housing, 4: rear housing,
5: Metal plate (shield plate), 5A: Support piece,
5B: bent portion, 5C: side, 5D: contact piece,
6: heat dissipation sheet, 7: connecting member, 8: seal ring,
10: image sensor, 11: first substrate, 12: second substrate,
20: board-to-board connector, 21: connector terminal,
100: vehicle, 101: side camera, 102: rear camera

Claims (5)

a housing in which the lens unit is supported;
a first substrate supported within the housing and having an image sensor mounted thereon, the image sensor having a light receiving surface corresponding to an image forming surface of the lens unit;
a second substrate connected to the first substrate by a substrate-to-substrate connector disposed in the housing near a peripheral portion thereof;
a metal plate disposed within the housing so as to surround at least the second substrate;
an imaging device characterized in that the metal plate has a support piece bent inwardly at a position away from the board-to-board connector so as to support the surface of the second substrate that faces the first substrate. a heat dissipation sheet is provided between the first substrate and the second substrate, and the heat dissipation sheet is in contact with electronic components attached to the first substrate and the second substrate;
2. The imaging device according to claim 1, wherein an end of the heat dissipation sheet is supported by being sandwiched between the support piece and the second substrate. the second substrate has a polygonal shape in a plan view,
the metal plate has a plurality of sides having bent portions corresponding to peripheral corners of the second substrate,
3. The imaging device according to claim 1, wherein the support pieces are provided in pairs on opposing sides. An imaging device according to any one of claims 1 to 3, characterized in that the metal plate has a contact piece that elastically contacts the surrounding housing. A vehicle equipped with the imaging device according to any one of claims 1 to 4.

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