Sensor device

Abstract

The sensor position may shift due to the expansion and contraction of the hardening paste. [Solution] A sensor device comprising a housing, a sensor component, a sensor substrate on which the sensor component is mounted, a curable paste installed on the housing side of the sensor substrate, and a sheet member installed between the curable paste and the housing, wherein the sensor substrate, the curable paste, the sheet member, and the housing are installed in contact with each other in that order, and heat is conducted from the sensor substrate to the housing side via the curable paste and the sheet member.

Description

Technical Field

[0001] The present invention relates to a sensor device provided with a curable thermal conductive paste.

Background Art

[0002] In an imaging device, there are an imaging element which is a sensor that receives light of a subject, and an imaging element substrate on which the imaging element is mounted. Since the imaging element generates a large amount of driving power and heat, there are problems such as deterioration of image quality and reduction of lifespan due to heat.

[0003] Therefore, as a method for efficiently dissipating the heat of the imaging element, a heat conductive member is attached between the imaging element substrate and the housing, and a heat dissipation structure by heat conduction is often used. Since the imaging element is positionally adjusted and mounted in units of several μm with respect to the focus position of an optical system composed of a lens or the like, if mechanical stress is applied to the imaging element substrate, the focus position will fluctuate. Particularly in an imaging device that measures distance using the principle of triangulation, since the distance is calculated from the focus position, the fluctuation of the focus position also affects the measurement of the distance. Therefore, a film-like member such as a graphite sheet rich in curvature that has little influence on the variation of the fixed position of the imaging element is used as the heat conductive member. Since the film-like heat conductive member is in a thin film shape and has excellent flexibility, even when the imaging element substrate and the housing are connected, mechanical stress due to thermal expansion and thermal contraction can be reduced. (For example, Patent Document 1)

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, sheet-type thermal conductive materials, being thin films, suffer from insufficient thermal conductivity even when using graphite sheets with very high thermal conductivity, resulting in inadequate heat dissipation. Furthermore, they impose mechanical stress when attached to the image sensor substrate, can only be attached to flat surfaces due to their sheet shape, and heat transfer occurs in the longitudinal direction, preventing uniform heat distribution across the substrate. Therefore, curable thermal conductive paste is used as a material to address these issues. When curable thermal conductive paste is placed between the image sensor substrate and the housing, its paste-like nature reduces mechanical stress during assembly. Additionally, its hardening after assembly allows for direct connection of the two components, which is advantageous for heat transfer over short distances. However, curable thermal conductive paste can impose mechanical stress on the image sensor substrate due to thermal expansion and contraction, potentially causing the sensor, which is sensitive to positional accuracy, to shift.

[0006] The present invention aims to provide a sensor device that improves measurement accuracy by reducing the influence of sensor position shifts due to thermal expansion and contraction of the curable thermal conductive paste, while maintaining a structure that allows for efficient heat dissipation by connecting the image sensor substrate and housing with a curable thermal conductive paste. [Means for solving the problem]

[0007] To achieve the above objectives, the present invention A sensor device comprising a housing, a sensor component, a sensor substrate on which the sensor component is mounted, a curable paste installed on the housing side of the sensor substrate, and a sheet member installed between the curable paste and the housing, characterized in that the sensor substrate, the curable paste, the sheet member, and the housing are installed in contact with each other in that order, and heat is conducted from the sensor substrate to the housing side via the curable paste and the sheet member. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a sensor device with improved measurement accuracy by reducing the influence of thermal expansion and contraction of the curable heat conductive paste due to temperature changes on the fixing position of the sensor substrate. [Brief explanation of the drawing]

[0009] [Figure 1] This is a diagram showing the arrangement of the imaging device of the present invention when mounted on a vehicle. [Figure 2] This is a block diagram showing the configuration of the imaging device of the present invention. [Figure 3] (a) An external view of the imaging device according to the first embodiment. (b) An exploded perspective view of the imaging device according to the first embodiment. [Figure 4] This is a cross-sectional view of the imaging device according to the first embodiment. [Figure 5] This figure shows the area around the heat conduction member 13 of the imaging device according to the first embodiment. [Figure 6] This is a conceptual diagram illustrating the principle of obtaining distance according to the first embodiment. [Figure 7] This figure shows the area around the heat conduction member 13 of the imaging device according to the second embodiment. [Figure 8] This figure shows the area around the heat conduction member 13 of the imaging device in a modified example of the second embodiment. [Figure 9] This figure shows variations in the cuts of the sheet member 7 of the imaging device in a modified example of the second embodiment. [Figure 10] This figure shows the area around the heat conduction member 13 of the imaging device according to the third embodiment. [Figure 11] This figure shows the area around the heat conductive member 13 of the imaging device in a modified example 1 of the third embodiment. [Figure 12] This is a diagram showing the area around the heat conductive member 13 of the imaging device, which is a modified example of the third embodiment. [Figure 13] This is a cross-sectional view of a sensor device according to a modified example 3 of the third embodiment. [Modes for carrying out the invention]

[0010] <First Embodiment> Embodiments of the present invention will be described below. Note that the figures used in the following description are simplified schematics. Dimensions and proportions shown in the drawings do not necessarily correspond to actual dimensions.

[0011] The imaging device 1 of the present invention can be mounted on a vehicle 100, which is a moving object. Figure 1(a) is a diagram showing the mounting position of the imaging device 1 on the vehicle 100. The imaging device 1 mounted on the vehicle 100 is an on-board camera. The imaging device 1 is an imaging device that monitors the front and sides of the vehicle 100 as it is moving, and can be positioned near the top of the front windshield or near the top of the A-pillar inside the passenger compartment of the vehicle 100. The imaging device 1 in Figure 1(b) is an imaging device that monitors the front and sides of the vehicle 100 as it is moving, and can be positioned near the grille, bumper, or headlights at the front of the vehicle. The imaging device 1 in Figure 1(c) can be installed at the rear of the vehicle 100 for monitoring the rear and sides of the vehicle 100. The imaging device 1 in Figure 1(d) can be installed on the side mirrors of the vehicle 100 for monitoring the left and right sides of the vehicle's surroundings, both in front of and behind the vehicle 100. Furthermore, the on-board camera is not limited to these, and includes imaging devices installed in various positions that can capture images of the sides, front, and rear.

[0012] <In-vehicle imaging device and vehicle control functions> Next, the imaging device 1 and vehicle 100, which are the imaging devices of the embodiment, will be described. Figure 2 is a functional block diagram of the imaging device 1 and vehicle 100 according to the embodiment. Note that some of the functional blocks shown in Figure 2 are realized by having a computer (not shown) included in the imaging device 1 and vehicle 100 execute a computer program stored in a memory (not shown) which is a storage medium.

[0013] However, some or all of these may be implemented in hardware. Hardware options include dedicated circuits (ASICs) and processors (reconfigurable processors, DSPs). Furthermore, each functional block shown in Figure 2 does not necessarily have to be housed in the same enclosure; they may be composed of separate devices connected to each other via signal paths.

[0014] The imaging device 1 includes an imaging element 9 (sensor component), an imaging optical system 8, an image processing unit 200, a recognition unit 201, a camera control unit 202, a memory unit 203, a communication unit 204, etc. The imaging element 9 (sensor component) is a semiconductor image sensor element such as a CMOS (Complementary Metal Oxide Semiconductor) sensor.

[0015] The imaging device 1 of the embodiment is mounted on a vehicle 100, and the camera unit 900 composed of the imaging optical system 8 and the imaging element 9 is configured to photograph at least one direction in front of, behind, or on the side of the vehicle 例如100. Note that a plurality of camera units 900 may be provided on the vehicle 100.

[0016] The image processing unit 200 performs image processing such as black level correction, gamma curve adjustment, noise reduction, digital gain adjustment, demosaicing processing, data compression, etc. on the image signal acquired by the imaging element 9, and generates a final image signal.

[0017] In addition, the output of the image processing unit 200 is supplied to the recognition unit 201, the ECU 101 (Electric Control Unit) of the vehicle 100, and the camera control unit 202.

[0018] The recognition unit 201 performs a process of recognizing objects such as surrounding people and vehicles by performing image recognition based on the image signal. Deep learning is used for this recognition process. For example, as deep learning, it is preferable to use YOLO (You Only Look Once) which is easy to learn and fast to detect. Also, as other deep learning, SSD (Single Shot MultiBox Detector), Faster R-CNN (Regional Convolution Neural Network) may be used. Or, Fast R-CNN, R-CNN, etc. may be used.

[0019] In this embodiment, the recognition unit 201 also calculates the distance to the recognized object. One method for calculating the distance is to estimate the distance using deep learning. For example, one method is to calculate the distance value by analyzing information such as the blur of the image of the detected object using deep learning. Another method is to calculate the distance using the principle of triangulation with the imaging device. This recognition process, including distance estimation, is performed on the image input from the image processing unit 200, and the recognition result is output to the subsequent ECU 101.

[0020] In this embodiment, the imaging device 1 is described using an example of an automobile, but it can be any mobile device such as an aircraft, train, ship, drone, AGV, or robot.

[0021] The camera control unit 202 has a built-in CPU and memory that stores computer programs, and the CPU controls each part of the imaging device 1 by executing the computer programs stored in the memory.

[0022] Furthermore, the camera control unit 202 functions as a control means, for example, controlling the length of the exposure period for each frame of the image sensor 9 and the timing of the control signals.

[0023] The storage unit 203 includes, for example, a recording medium such as a memory card or hard disk, and can store and read image signals. The communication unit 204 is equipped with wireless and wired interfaces and outputs the generated image signals to the outside of the imaging device 1 and receives various signals from the outside.

[0024] The ECU101 has a built-in CPU and memory that stores computer programs, and the CPU executes the computer programs stored in the memory to control various parts of the vehicle 100.

[0025] The output of the ECU 101 is supplied to the vehicle control unit 102 and the display unit 103. The vehicle control unit 102 functions as a movement control means that controls the driving, stopping, and direction of the vehicle as a moving object based on the output of the ECU 101. The display unit 103 functions as a display means and includes a display element such as a liquid crystal device or an organic EL, and is mounted on the vehicle 100.

[0026] In this embodiment, the ECU 101 receives recognition result information from the recognition unit 201 and can perform vehicle stopping control (such as automatic braking) according to the content of the recognition result. The ECU 101 also receives an image from the image processing unit 200 and transmits it to the display unit 103 along with the recognition result.

[0027] Based on the output of the ECU 101, the display unit 103 displays various information to the driver of the vehicle 100, such as images acquired by the image sensor 9, recognition results from the recognition unit 201, and the vehicle's driving status, for example using a GUI.

[0028] Furthermore, the image processing unit 200, recognition unit 201, etc. shown in Figure 2 do not necessarily have to be mounted on the vehicle 100. For example, the vehicle 100 may be mounted on an external terminal provided separately for remotely controlling the vehicle 100 or for monitoring the movement of a moving object.

[0029] Figure 3 shows an imaging device 1 according to an embodiment of the present invention. Figure 3(a) shows an external view of the imaging device 1. Figure 3(b) shows an exploded perspective view of the imaging device 1. Figure 4 shows a cross-sectional view of the imaging device 1 according to an embodiment of the present invention.

[0030] As shown in Figure 3, the imaging device 1 of this embodiment mainly consists of an upper housing 2, a lower housing 3, and a rear housing 4, within which the image sensor unit 5, the main circuit board 6, and the like are housed.

[0031] The upper housing 2 is made of a metal such as aluminum or resin and forms the outer shell of the imaging device 1 in the X+ direction. The upper housing 2 comprises a front wall portion 21, an upper wall portion 22, a right side wall portion 23, a left side wall portion 24, a front side wall portion 25, and an upper side wall portion 26. The front wall portion 21 is a flat plate shape and is arranged approximately parallel to the image sensor 9, which will be described later. A hole for inserting the image sensor unit 5 is provided in the front wall portion 21. The upper wall portion 22 intersects with the front wall portion 21. The upper wall portion 22 extends from the end face of the front wall portion 21 slightly towards the Z- direction on the X+ direction side and is a flat plate shape. A hole is provided in the upper wall portion 22 so as not to interfere with the image sensor unit 5, and it is connected to the hole in the front wall portion 21. Heat dissipation fins (not shown) may be arranged on the Z+ direction side of the upper wall portion 22. The main circuit board 6, on which electronic components described later are mounted, is attached to the Z- direction side of the upper wall portion 22. The front wall portion 21 of the upper housing 2 is positioned to face the outside of the vehicle directly, and although not shown in Figure 3, the upper housing 2 mainly serves as the mounting portion to the vehicle.

[0032] The lower housing 3 is made of a metal such as aluminum or resin, and forms the outer shell of the imaging device 1 on the Z-direction side. The planar portion 31 is parallel to the upper wall portion 22 and has a flat plate shape. The lower housing 3 is installed so as to close the Z-direction side of the upper housing 2.

[0033] The rear housing 4 is made of a metal such as aluminum or resin, and forms the outer shell of the imaging device 1 on the X-direction side. The front wall portion 41 of the rear housing 4 is positioned approximately parallel to the image sensor substrate 10 and is joined to the upper housing 2 by fastening components such as screws (not shown). Heat dissipation fins (not shown) may be attached to the rear wall portion 42 of the rear housing 4.

[0034] The image sensor unit 5 mainly consists of an imaging optical system 8, an image sensor 9 (sensor component), and an image sensor substrate 10.

[0035] The imaging optical system 8 houses multiple lenses 82 and multiple spacers 83 inside a cylindrical lens barrel 81 made of metal such as aluminum or resin. A wide-angle lens 84 is housed in the first lens at the end facing the object being imaged and is held in place by a retaining ring 85.

[0036] The lens 82 and wide-angle lens 84 are made of transparent materials such as glass or resin. The spacer 83 and retaining ring 85 are made of metal such as aluminum or resin.

[0037] In Figure 4, multiple lenses 82 and spacers 83 are arranged alternately, with the same shape and quantity; however, they may be of different shapes and in different quantities. The order in which they are arranged does not matter.

[0038] The ends of the imaging optical system 8 are attached to the image sensor substrate 10 at approximately a right angle via adhesive or the like (not shown).

[0039] The imaging optical system 8 does not necessarily have to be directly attached to the image sensor substrate 10. For example, it may be attached indirectly via the upper housing 2 or other components.

[0040] The image sensor 9 (sensor component) is mounted on the image sensor substrate 10 on the imaging optical system 8 side and is housed in the cylindrical part of the imaging optical system 8. The image sensor 9 is the main heat source of the image sensor unit 5.

[0041] The image sensor substrate 10 has a flat plate shape extending in the Y and Z directions. A temperature sensor 51 is attached to the side of the image sensor substrate 10 opposite to the imaging optical system 8. The temperature sensor 51 is used to acquire the temperature of the image sensor 9 and the imaging optical system 8.

[0042] The image sensor unit 5 is inserted into a hole in the upper housing 2 and joined by screws, adhesive, etc. (not shown). A heat conductive member 13 is laminated on the X-direction side of the image sensor unit 5. The heat conductive member 13 is made of a material such as silicone and has the appearance of a thin, rubbery film. The heat conductive member 13 is a material also known as a hardening paste or gap filler. When applied, it is soft like a cream, and there is little mechanical stress when assembling and bonding the parts. After application, it hardens to a low-hardness rubber-like consistency through a chemical reaction, and is a material that has the characteristic of fixing to the parts it is bonding with.

[0043] A sheet member 7 is laminated on the X-direction side of the heat conductive member 13. The sheet member 7 is also in contact with the front wall portion 41 of the rear housing 4, and conducts heat generated from the image sensor 9 and other components to the rear housing 4. The sheet member 7 is made of a material such as metal or resin and is in the form of a film or sheet. The heat conductive member 13 may also be in partial contact with the front wall portion 41 of the rear housing 4. The heat received by the front wall portion 41 of the rear housing 4 is mainly dissipated from the rear wall portion 42. It is desirable that the sheet member 7 has a thermal conductivity of 50 W / m·k or more in the planar direction.

[0044] The main circuit board 6 has a flat plate shape extending in the X and Y directions. The main circuit board 6 is joined to the boss portion of the upper wall portion 22 of the upper housing 2 by fastening components such as screws 52. The main circuit board 6 may also be joined to the lower housing 3. The main circuit board 6 and the image sensor board 10 are electrically connected via wiring 12. The main circuit board 6 has multiple electronic components on both the Z+ side and the Z- side. The multiple electronic components mounted on the main circuit board 6 include a camera control IC 11.

[0045] The camera control IC 11 provides integrated control of the entire imaging device 1. A heat conductive member 14 is laminated on the Z+ side of the camera control IC 11. The heat conductive member 14 is laminated in contact with at least some of the multiple electrical components, including the camera control IC 11. The heat conductive member 14 is in contact with the Z- side of the upper wall portion 22 of the upper housing 2 and conducts heat from the electronic components. The heat received on the Z- side of the upper wall portion 22 of the upper housing 2 is dissipated from the Z+ side of the upper wall portion 22. In addition, the heat conductive member 14 may also be installed on the Z- side of the main circuit board 6 to enhance the heat dissipation effect.

[0046] Next, the operation and effects of the imaging device 1 of this embodiment will be described.

[0047] Figure 5 shows the area around the heat conductive member 13 in an embodiment of the present invention. Figure 5(a) is an exploded perspective view of the area around the heat conductive member 13. Figure 5(b) is a cross-sectional view of the area around the heat conductive member 13 at room temperature and low temperature. In Figure 5(b), the low temperature indicates that the imaging device 1 is at a lower temperature than at room temperature due to fluctuations in ambient temperature. In the room temperature view of Figure 5(b), the heat conductive member 13 and the sheet member 7 (shaded area in Figure 5(b)) are stacked in that order on the image sensor substrate 10 on which the image sensor 9 is mounted, and the sheet member 7 is installed so as to be in contact with the rear housing 4. Although not shown in Figure 5, the image sensor substrate 10 and the rear housing 4 are fixed to other components such as the upper housing 2. The heat conductive member 13 is fixed to the image sensor substrate 10 and the sheet member 7 by adhesive, but the rear housing 4 side of the sheet member 7 is only press-fitted.

[0048] In other words, the heat conductive member 13 is bonded to the image sensor substrate 10 at one end and to the sheet member 7 at the other end. The sheet member 7 is bonded to the heat conductive member 13 at one end and not to the rear housing 4 at the other end.

[0049] Therefore, if the heat conduction member 13 is assembled at room temperature, in a temperature environment above room temperature, the heat conduction member 13 expands, and the sheet member 7 remains in contact with the rear housing 4. Conversely, in a temperature environment below room temperature (low temperature), the heat conduction member 13 contracts, and as shown in Figure 5(b) at low temperature, the sheet member 7 moves in the direction of the arrow and can move away from the rear housing 4.

[0050] In the low-temperature conditions shown in Figure 5(b), if the sheet member 7 is absent, the heat conductive member 13 is bonded to both the image sensor substrate 10 and the rear housing 4. Therefore, when the heat conductive member 13 contracts, a load is applied that pulls the image sensor substrate 10 and the rear housing 4 toward the heat conductive member 13.

[0051] Therefore, the position of the image sensor substrate 10 and the image sensor 9 mounted on the image sensor substrate 10 shifts due to the load, causing the focus position to change.

[0052] However, as mentioned above, by attaching the sheet member 7, the heat conductive member 13 can separate from the rear housing 4 together with the sheet member 7 without pulling the image sensor substrate 10 towards the heat conductive member 13. This prevents movement of the image sensor 9 and prevents fluctuations in the focus position. For improved assembly, the sheet member 7 may be made slightly adhesive and attached to the rear housing 4.

[0053] Figure 6 is a conceptual diagram illustrating the principle of distance acquisition in the first embodiment. Figure 6(a) shows a state where the focus position is not changing, and Figure 6(b) shows a state where the focus position has changed compared to Figure 6(a).

[0054] According to the imaging device 1 of this embodiment, distance measurement information can be obtained. The image sensor 9 mounted on the imaging device 1 receives light from the object to be imaged (dotted line in Figure 6) via the imaging optical system 8 and uses the principle of triangulation to acquire a phase difference 91, which is the shift in the image signal, for each pixel. The image sensor 9 has the function of measuring the phase difference by dividing one pixel into multiple photodiodes, and has the function of calculating the distance to the object to be imaged from the phase difference. The phase difference 91 can be multiplied by a coefficient set for each imaging device to obtain a defocus amount 92. The defocus amount 92 can be converted into the distance 93 to the object to be imaged using the lens design value (focal length, focus distance) and the lens formula. Figure 6(b) shows the state in which the image sensor 9 has moved due to the contraction of the heat conductive member 13 (not shown in Figure 6) compared to Figure 6(a). The actual amount of movement is in the order of several microns. It can be seen that the values ​​of the phase difference 91 and the defocus amount 92 change due to the movement of the image sensor 9. The distance 93 to the target being imaged is calculated by first determining the defocus amount 92 from the phase difference 91, and then calculating the distance 93 based on the defocus amount 92, in order to determine the accurate distance to the target being imaged. Therefore, if the position of the image sensor 9 moves, the position to the target being imaged changes (shaded area in Figure 6(b)), and a distance measurement error occurs.

[0055] Therefore, in order to prevent the image sensor 9 from moving, the sheet member 7 described in Figure 5(b) is used to reduce the load on the image sensor substrate 10. As a result, as shown in Figure 6(a), the image sensor 9 is held in the position as designed, and the distance 93 to the object to be imaged can be calculated accurately.

[0056] Based on the above, the imaging device 1 of the present invention reduces the load on the main substrate 6 when the heat conductive member 13 contracts due to a decrease in temperature, by laminating the sheet member 7 on the heat conductive member 13, thereby suppressing the movement of the image sensor 9. This makes it possible to easily reduce the effect of fluctuations in the focus position and improve the distance measurement accuracy.

[0057] <Second Embodiment> An imaging device 1 according to the second embodiment of this disclosure will be described with reference to Figure 7.

[0058] In the first embodiment, a method for reducing the shrinkage load of the heat conduction member 13 using a sheet member 7 was described. In the second embodiment, variations in the shape of the sheet member 7 and the effect of reducing the shrinkage load will be described. The imaging device in the second embodiment is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be described, and similar parts will be omitted from the description. Also, parts corresponding to those in the first embodiment will be denoted by the same reference numerals.

[0059] Figure 7 is an exploded perspective view showing the area around the heat conductive member 13 in the second embodiment. The sheet member 7 in Figure 7(a) is given spring properties by bending.

[0060] The bending process involves bending the rectangular sheet member 7 at two predetermined positions on each of its longitudinal sides (a total of four bending positions). The first bending position and the second bending position, both on the side closest to the sheet member, are performed in different directions. As shown in Figure 7(a), the sheet member 7 has a surface that contacts the rear housing 4 from each longitudinal side of the rectangular sheet member 7 up to the first bending position, and is bonded to the rear housing 4 (bonding surface in Figure 7). Bonding fixes the sheet in place and improves ease of assembly. Furthermore, using a sheet with high thermal conductivity, such as a graphite sheet, improves thermal conductivity through bonding. Bonding methods include adhesive, double-sided tape, and screws. When bonding the bonding surface to the rear housing 4, creating a Z-shape in the bent section allows for some leeway, enabling springiness that allows movement in the direction of the dashed line in Figure 7(a) after bonding. Therefore, even if the heat conduction member 13 contracts, the springiness of the sheet member 7 can reduce the contraction load.

[0061] Figure 7(b) shows that the sheet member 7 is given spring properties by bending it, similar to Figure 7(a). The difference from Figure 7(a) is that there is one bonding surface and two bending processes, and it is fixed in a cantilevered manner. In Figure 7(b), similar to Figure 7(a), when bonding the bonding surface to the rear housing 4, the bent part is made with a margin such as a Z shape, so that after bonding, spring properties that allow movement in the direction of the dashed line in Figure 7(a) can be obtained. Therefore, even if the heat conductive member 13 contracts, the contraction load can be reduced by the spring properties of the sheet member 7.

[0062] Figure 7(c) shows that the sheet member 7 is made flexible by bonding it in only one place. Figure 7(c) is fixed in a cantilevered manner, similar to Figure 7(b), but differs in that there is no bending process. As shown in Figure 7(c), the sheet member 7 has a rectangular shape and is bonded to the rear housing 4 from one of its longitudinal sides to a predetermined position. If the sheet member 7 is made of a flexible material, it can bend in a rotational direction with the bonded end (dotted line in Figure 7) as the central axis. Therefore, even if the heat conductive member 13 contracts, the springiness of the sheet member 7 can reduce the contraction load.

[0063] Figure 7(d) shows how the heat conduction member 13 and the rear housing 4 are bonded together by providing holes in the sheet member 7. By providing holes in a portion of the surface of the sheet member 7 that contacts the heat conduction member 13, the heat conduction member 13 can be bonded and fixed to the rear housing 4 through the holes in the sheet member 7. By bonding the heat conduction member 13 to the rear housing 4, the thermal resistance can be reduced, and heat from the main substrate 6 can be efficiently transferred to the rear housing 4. In addition, the load on the surface of the heat conduction member 13 that is in contact with the sheet member 7 can be reduced. However, when the heat conduction member 13 contracts within the area of ​​the bonded surface with the rear housing 4, it will put a load on the image sensor substrate 10. The amount of load generated can be adjusted by adjusting the position, number, and size of the holes in the sheet member 7, so it is effective to adjust the holes in the sheet member 7 appropriately in order to minimize the impact on the movement of the image sensor 9.

[0064] Figure 7(e) shows how the sheet member 7 is made smaller than the bonding area of ​​the heat conduction member 13, thereby bonding and fixing the heat conduction member 13 to the rear housing 4. Because the sheet member 7 is smaller than the heat conduction member 13, it is covered by the heat conduction member 13. In Figure 7(e), the round sheet member 7 is placed in the center of the round heat conduction member 13, so the bonding surface between the heat conduction member 13 and the rear housing 4 is donut-shaped. The central part of the heat conduction member 13 can be reduced by the sheet member 7. A load is generated at the bonding surface between the heat conduction member 13 and the rear housing 4, but the bonding of the heat conduction member 13 and the rear housing 4 leads to a reduction in thermal resistance, so that the heat from the main substrate 6 can be efficiently transferred to the rear housing 4. In Figure 7(e), the sheet member 7 is round and placed in the center of the heat conduction member 13, but the shape of the sheet member 7 does not have to be round, and the installation position does not have to be in the center.

[0065] Figure 7(f) shows a method for fixing the position of the sheet member 7. In Figure 7(f), two bosses are installed on the rear housing 4, and two holes are drilled in the sheet member 7. By passing the two holes in the sheet member 7 through the two bosses on the rear housing 4, the sheet member 7 can be fixed during and after assembly. The sheet member 7 can move in the direction of the dashed line in Figure 7(f), so this does not affect the load reduction effect due to contraction. Fixing the sheet member 7 makes positioning during assembly easy and prevents misalignment between the heat conductive member 13 and the sheet member 7 after assembly. In Figure 7(f), the sheet member 7 is fixed using bosses and holes, but it may also be fixed using the outer shape of the sheet member 7.

[0066] <Modified form of the second embodiment> An imaging device 1 according to a modified example of the second embodiment of this disclosure will be described with reference to Figure 8.

[0067] In the first embodiment, a method for reducing the shrinkage load of the heat conduction member 13 using a sheet member 7 was described. In the modified version of the second embodiment, the effect of reducing the shrinkage load by adding cuts to the sheet member 7 will be described. The imaging device in the modified version of the second embodiment is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be the focus of the explanation, and similar parts will be omitted. Also, parts corresponding to those in the first embodiment will be denoted by the same reference numerals.

[0068] Figure 8 shows the area around the heat conduction member 13 in a modified example of the second embodiment. Figure 8(a) is an exploded perspective view of the area around the heat conduction member 13. Figure 8(b) is a cross-sectional view of the area around the heat conduction member 13 at room temperature and low temperature. The configuration is the same as in Figure 5 of the first embodiment. The difference is that a notch has been added to the center of the sheet member 7. It is desirable that this notch be located at the part in contact with the heat conduction member 13. As shown in Figure 8(a), a cross-shaped notch is made in the center of the sheet member 7. Because of the notch, even if a part of the sheet member 7 is bonded to the rear housing 4 (not shown in Figure 8), the notched portion can bend in the direction of the arrow, as shown in Figure 8(b) at low temperature. In other words, the structure allows the notched portion to be displaced in accordance with the contraction of the heat conduction member 13. Therefore, even if the heat conduction member 13 contracts, the contraction load can be reduced by the bending of the notched portion of the sheet member 7.

[0069] Figure 9 shows variations in the cuts of the sheet member 7 in a modified example of the second embodiment. In the modified example of the second embodiment, a cross-shaped cut was made in the center of the sheet member 7, but the same effect can be obtained with various shapes of cuts, not just a cross shape.

[0070] Figure 9(a) shows a shape in which an X-shaped cut is added to the cross-shaped cut. In the cross-shaped cut, the center of the sheet member 7 was divided into four sections, but by adding the X-shaped cut, it is divided into eight sections, resulting in a shape that is more flexible.

[0071] Figure 9(b) shows the shape with an added H-shaped cut. Since only the central part of the sheet member 7 is divided into two, the effect does not change much even if the assembly position of the heat conductive member 13 is slightly shifted in the longitudinal direction.

[0072] Figure 9(c) shows a shape with a round hole in the center of a cross-shaped cut. As explained in Figure 7(d), by adding a hole, the curing thermal conductive paste and the housing are directly bonded, which can reduce thermal resistance.

[0073] The variations shown in Figure 9 are just examples; various cut shapes, such as U-shapes or star shapes, can be used depending on the situation.

[0074] <Third Embodiment> An imaging device 1 according to the third embodiment of this disclosure will be described with reference to Figure 10.

[0075] In the first embodiment, a method for reducing the contraction load of the heat conduction member 13 using a sheet member 7 will be described, and in the third embodiment, a method for reducing the expansion load of the heat conduction member 13 will be described using a shape in which a groove is added to the rear housing 4. The imaging device in the third embodiment is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be explained, and the explanation of similar parts will be omitted. Also, parts corresponding to those in the first embodiment will be denoted by the same reference numerals.

[0076] Figure 10 shows the area around the heat conduction member 13 in the third embodiment. Figure 10(a) is an exploded perspective view of the area around the heat conduction member 13. Figure 10(b) is a cross-sectional view of the area around the heat conduction member 13 at room temperature and at high temperature. In Figure 10(b), "high temperature" indicates that the imaging device 1 is at a higher temperature than at room temperature due to fluctuations in ambient temperature. The configuration in Figure 10 is the same as in Figure 7 in the first embodiment. The difference is that a groove has been added to the rear housing 4.

[0077] The first and second embodiments described a method for reducing the load when the heat conductive member 13 contracts due to a decrease in ambient temperature. The third embodiment describes a method for reducing the load when the heat conductive member 13 expands due to a rise in ambient temperature. In the third embodiment, an expansion load occurs in the opposite direction to the load direction described in the first and second embodiments. As a result, the image sensor substrate 10 on which the image sensor 9 is mounted is pushed by the expansion load, causing the image sensor 9 to move in the opposite direction to the movement direction of the image sensor 9 described in Figure 6(b). Although the direction of movement is different, a distance measurement error occurs, similar to Figure 6(b). Therefore, in Figure 10, a groove is provided in the rear housing 4 to secure space when the heat conductive member 13 expands. In Figure 9(b), the sheet member 7 at room temperature maintains a flat shape, and there is space in the groove of the rear housing 4. In Figure 10(b), the heat conductive member 13 expands at high temperatures and bulges in the direction of the arrow. When the expanded portion of the heat conductive member 13 comes into contact with the rear housing 4, the thermal resistance is reduced and heat dissipation is improved. In addition, when the expanded portion of the heat conductive member 13 fits into the groove of the rear housing 4, the expansion load is reduced.

[0078] As described above, by providing grooves in the rear housing 4, the image sensor substrate 10 can reduce the load in the direction of pressure from the heat conductive member 13, thereby preventing movement of the image sensor 9 and preventing fluctuations in the focus position.

[0079] <Modification 1 of the third embodiment> An imaging device 1 according to Modification 1 of the Third Embodiment of this Disclosure will be described with reference to Figure 11.

[0080] In the first embodiment, a method for reducing the shrinkage load of the heat conduction member 13 using a sheet member 7 was described. In the third embodiment, modification 1, the effect of reducing the shrinkage load when the sheet member 7 is installed on the image sensor substrate 10 side (sensor substrate side) and the heat conduction member 13 is installed on the housing side will be described. The imaging device in the third embodiment, modification 1 is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be described, and similar parts will be omitted from the description. Also, parts corresponding to those in the first embodiment will be denoted by the same reference numerals.

[0081] Figure 11 shows the area around the heat conduction member 13 in Modification 1 of the third embodiment. Figure 11(a) is an exploded perspective view of the area around the heat conduction member 13. Figure 11(b) is a cross-sectional view of the area around the heat conduction member 13 at room temperature and low temperature. The components are the same as in Figure 5 of the first embodiment. The difference is that the sheet member 7 is located on the image sensor substrate 10 side (sensor substrate side). As shown in Figures 11(a) and 11(b), the components are stacked in the order of image sensor substrate 10, sheet member 7, heat conduction member 13, and rear housing 4. At low temperature in Figure 11(b), the heat conduction member 13 contracts, and the sheet member 7 moves in the opposite direction to the first embodiment, towards the rear housing 4 side (direction of the arrow in Figure 11), and can move away from the image sensor substrate 10. Therefore, even if the heat conduction member 13 contracts, the movement of the sheet member 7 can reduce the contraction load and prevent the image sensor 9 from moving.

[0082] <Modified example 2 of the third embodiment> An imaging device 1 according to a modified example 2 of the third embodiment of this disclosure will be described with reference to Figure 12.

[0083] In the first embodiment, a method for reducing the shrinkage load of the heat conduction member 13 using a sheet member 7 was described. In the third embodiment, modification 2, the effect of reducing the shrinkage load of a configuration in which a substrate 15 and a heat conduction member 16 are added will be described. The imaging device in the third embodiment, modification 2 is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be described, and the same parts will be omitted from the description. Also, parts corresponding to those in the first embodiment will be denoted by the same reference numerals.

[0084] Figure 12 shows the area around the heat conduction member 13 in a modified example 2 of the third embodiment. Figure 12(a) is an exploded perspective view of the area around the heat conduction member 13. Figure 12(b) is a cross-sectional view of the area around the heat conduction member 13 at room temperature and low temperature. The basic configuration of Figure 12 is the same as that of Figure 5 in the first embodiment, except that the components of the substrate 15 and the heat conduction member 16 have been added. The substrate 15 is fixed to components such as the image sensor substrate 10 and the rear housing 4 (not shown in Figure 12), and the heat conduction member 16 is adhesively fixed to the substrate 15 and the rear housing 4. As shown in Figure 12(b) at room temperature, the heat conduction member 13, sheet member 7, substrate 15, heat conduction member 16, and rear housing 4 are stacked in that order on the image sensor substrate 10 on which the image sensor 9 is mounted, and each component is in contact with the others. Therefore, in Figure 12, heat from the image sensor substrate 10 can be transferred to the rear housing 4. Furthermore, as shown in Figure 12(b) at low temperatures, even if the heat conductive member 13 shrinks, the sheet member 7 can move in the direction of the arrow and separate from the substrate 15. Therefore, by reducing the shrinkage load, it is possible to prevent the image sensor 9 from moving.

[0085] <Modification 3 of the third embodiment> A sensor device relating to a modified example 3 of the third embodiment of this disclosure will be described with reference to Figure 13.

[0086] In the first embodiment, a method was described for reducing the shrinkage load of the heat conductive member 13 and suppressing the movement of the image sensor 9 by using a sheet member 7 in the imaging device 1. In the third embodiment, modification 3, the effect of suppressing the amount of movement by using a sheet member and a hardening type heat conductive paste is described not only for imaging devices but also for other devices that use sensors. Note that the effect in the sensor device of the third embodiment, modification 3 is basically the same as in the first embodiment. Therefore, in the following, the differences between the two will be explained, and similar parts will be omitted from the explanation.

[0087] Figure 13 is a cross-sectional view of a sensor device according to a third modified example of the third embodiment. The sensor device in Figure 13 is a distance measuring device equipped with a light-emitting unit and a light-receiving sensor unit, and partially shows the configuration around the sensor unit necessary for measurement.

[0088] The light-emitting substrate 301 is equipped with a light-emitting unit 302 and emits light for distance measurement (irradiated light indicated by arrow (1) in Figure 13). When the emitted light reaches the light-emitting unit of the object, it becomes reflected light (reflected light indicated by arrow (2) in Figure 13) and reaches the light-receiving sensor unit 303 mounted on the light-receiving sensor substrate 304. Distance can be measured using this emitted light and reflected light. For example, there is the TOF (Time Of Flight) method, which converts the time from the time the emitted light is emitted to the time the reflected light is received into distance, and the phase difference detection method, which measures the phase difference between the emitted light and the reflected light, calculates the time, and converts it into distance. The light-receiving sensor substrate 304 has a curable thermal conductive paste 305 and a sheet member 306 laminated on it to dissipate the heat generated from the light-receiving sensor unit 303 and other components. The sheet member 306 is in contact with the housing 307, and the heat from the light-receiving sensor substrate 304 can be transferred to the housing 307 by heat conduction. As explained in Figure 5, when the temperature of the sensor device decreases, the sheet member 306 separates from the housing 307 when the curing heat conductive paste 305 shrinks, reducing the shrinkage load of the curing heat conductive paste 305 and preventing the position of the light receiving sensor unit 303 from shifting.

[0089] <Other> The embodiments of the imaging apparatus of the present invention have been described above. However, the embodiments are not particularly limited to the above forms. It is also possible to implement the apparatus in various modified and improved forms that can be carried out by those skilled in the art.

[0090] In the above embodiment, a CMOS image sensor was used as the image sensor 9 (sensor component), but a sensor such as a SPAD (SINGLE PHOTON AVALANCHE DIODE) image sensor may also be used.

[0091] The material of the curing paste for the heat conductive members 13 and 14 is not limited to a silicone-based material. For example, urethane, modified silicone, etc. may be used. In addition, a type that hardens by mixing two or more materials, or a type that hardens with only one material, may be used.

[0092] The material of the sheet member 7 can be made of a material with high thermal conductivity, which will lower the thermal resistance and improve heat dissipation efficiency. For example, graphite sheets, copper foil, or aluminum foil may be used. The material may also be in the form of fibers or foam. [Explanation of symbols]

[0093] 1. Imaging device 2 Upper enclosure 3. Lower enclosure 4 Rear enclosure 5 Image sensor unit 6 Main circuit board 7 Sheet material 8. Imaging Optical System 9 Image sensor 10 Image sensor substrate 11 Camera control IC 12 Wiring 13 Heat Conducting Members 14 Heat Conducting Members 15 circuit boards 16 Heat conductive material 21 Front wall 22 Upper wall 23 Right side wall 24 Left side wall 25 Front wall 26 Upper wall 27 Top lid 41 Front wall 42 Rear wall 81 Telescope Tube 82 lenses 83 Spacer 84 Wide-angle lens 85 Retainer ring 51 Temperature sensor 52 screws 91 Phase difference 92 Defocus Amount 93 distance 100 vehicles 101 ECU 102 Vehicle Control Unit 103 Display section 200 Image Processing Unit 201 Recognition part 202 Camera Control Unit 203 Storage section 204 Communications Department 301 Light-emitting substrate 302 Light-emitting part 303 Light receiving sensor unit 304 Light-receiving sensor board 305 Curing-type heat-conducting paste 306 Sheet material 307 cabinets

Claims

1. A sensor device comprising a housing, a sensor component, a sensor substrate on which the sensor component is mounted, a curable paste installed on the housing side of the sensor substrate, and a sheet member installed between the curable paste and the housing, The sensor substrate, the curing paste, the sheet member, and the housing are arranged in that order so as to be in contact with each other, and the structure allows heat to be conducted from the sensor substrate to the housing side via the curing paste and the sheet member. A sensor device characterized by the following.

2. The sensor substrate is bonded to the curing paste, The curing paste is bonded to the sensor substrate at one end and to the sheet member at the other end. The sheet member has a structure in which one end is bonded to the curing paste, and the other end is not bonded to the housing. The sensor device according to claim 1, characterized by the following:

3. The aforementioned sheet member is At least one side is bent at a predetermined position, with two bends per side, and the section from one side to the first bend is bonded to the housing. The sensor device according to claim 2, characterized by the following:

4. The aforementioned sheet member is At least one side is bonded to the housing at a predetermined position. The sensor device according to claim 2, characterized by the following:

5. The curing paste is installed so as to be in contact with the housing. The sensor device according to claim 2, characterized by the following:

6. A sensor device comprising a housing, a sensor component, a sensor substrate on which the sensor component is mounted, a curable paste installed on the sensor substrate side of the housing, and a sheet member installed between the curable paste and the sensor substrate, The sensor substrate, the sheet member, the curing paste, and the housing are arranged in that order so as to be in contact with each other, and the structure allows heat to be conducted from the sensor substrate to the housing side via the sheet member and the curing paste. A sensor device characterized by the following.

7. The curing paste is installed so as to be in contact with the sensor substrate. The sensor device according to claim 6, characterized by the following:

8. The sheet member has a notch in the part that is in contact with the curing paste, and the notch is structured to be able to displace in accordance with the contraction and expansion of the curing paste. A sensor device according to claim 2 or claim 7, characterized by the above.

9. A sensor device comprising: a housing; a sensor component; a sensor substrate on which the sensor component is mounted; a second substrate different from the sensor substrate; a curable paste installed on the housing side of the sensor substrate; a second curable paste installed on the housing side of the second substrate; and a sheet member installed between the curable paste and the second substrate, The sensor substrate, the curing paste, the sheet member, the second substrate, the second curing paste, and the housing are arranged in contact with each other in that order, and heat is conducted from the sensor substrate to the housing side via the curing paste, the sheet member, the second substrate, and the second curing paste. A sensor device characterized by the following.

10. The aforementioned sensor is an image sensor that has the function of measuring phase difference by dividing one pixel into multiple photodiodes, and has the function of calculating the distance to the object being imaged from the phase difference. A sensor device according to any one of claim 2, claim 7, or claim 9, characterized by the following:

11. The sheet member has a thermal conductivity of 50 W / m·k or more in the planar direction. A sensor device according to any one of claim 2, claim 7, or claim 9, characterized by the following:

Images