Imaging apparatus

Abstract

To provide an imaging apparatus excellent in mountability, designability and ranging accuracy of a camera.SOLUTION: The imaging device includes a first camera having a first lens, a second camera having a second lens, a third camera having a third lens, and a case that houses the first camera, the second camera, and the third camera and is attached to the vehicle, in which the second lens is disposed at a position farther from the vehicle than the first lens and the third lens, a part of an imaging range of the first camera and a part of an imaging range of the second camera overlap each other, and a part of an imaging range of the second camera and a part of an imaging range of the third camera overlap each other.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an imaging device that is mounted on a vehicle and captures images of the surroundings of the vehicle. [Background technology]

[0002] In autonomous driving, it is necessary to sense the surroundings of the vehicle using a camera mounted on the vehicle and obtain highly accurate and high-density distance information.

[0003] In this regard, Patent Document 1 proposes a configuration as follows, with the aim of providing an imaging device and an in-vehicle camera system that can simultaneously perform wide-angle and telephoto shooting while having a simple configuration: "an imaging device comprising a camera having a telephoto lens, a wide-angle means, and at least one mirror that reflects light emitted from the wide-angle means and makes it incident on a part of the imaging surface of the camera." [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-181634 Summary of the Invention [Problem to be solved by the invention]

[0005] The imaging device in Patent Document 1 is a camera module whose optical system is composed of lenses with different angles of view (fisheye and narrow angle) and reflecting surfaces (prisms), and which forms images with different angles of view and optical axes on a single imaging element. As a result, it has problems such as no common imaging area and the short distance between the cameras making it impossible to achieve stereoscopic vision, reduced resolution due to forming multiple images on a single imaging element, and high manufacturing costs due to the complex optical structure that uses reflections from a prism.

[0006] In contrast, autonomous driving systems require technology that can measure distances and recognize the entire perimeter of the vehicle with high precision using multiple cameras. In particular, cameras for the side areas of the vehicle are expected to be mounted outside the passenger compartment, so ease of installation and design are also important.

[0007] To summarize these issues more specifically, autonomous driving requires imaging devices that are easy to install, have good design, and have good distance measurement accuracy.

[0008] Among these, ease of installation is an important factor in improving distance measurement performance, and the use of multiple cameras to obtain stereo information for distance measurement makes installation unstable (variable), which in turn affects distance measurement / recognition performance, necessitating improvements in the performance of the imaging device. Furthermore, in relation to installation, when designing and manufacturing an imaging device, it is necessary to consider where to install the cameras, assuming that it will be installed in a variety of vehicle models, and also aim for simplification of manufacturing when installing multiple cameras (simplification of manufacturing).

[0009] In terms of design, cameras for the side areas of the vehicle are expected to be mounted outside the vehicle cabin, so it is desirable that they contribute to ensuring safety from contact with pedestrians, vehicle performance such as aerodynamic characteristics, and distance measurement performance.

[0010] These requirements for ease of installation and design ultimately focus on good ranging accuracy, but to achieve good ranging accuracy, it is necessary to consider that variations in the mounting positions of multiple cameras can make ranging / recognition performance unstable, necessitating the need for improved accuracy. This means that it is necessary to achieve both ease of installation (mountability) of multiple cameras and improved recognition performance.

[0011] SUMMARY OF THE INVENTION In view of the above, an object of the present invention is to provide an imaging device that is easy to mount, has good design, and has good distance measurement accuracy. [Means for solving the problem]

[0012] In the present invention, the imaging device is configured as follows: "An imaging device to be installed in a vehicle, comprising a first camera having a first lens, a second camera having a second lens, a third camera having a third lens, and a case that houses the first camera, the second camera, and the third camera and is attached to the vehicle, wherein the second lens is positioned farther away from the vehicle than the first lens and the third lens, and wherein a portion of the imaging range of the first camera overlaps with a portion of the imaging range of the second camera, and a portion of the imaging range of the second camera overlaps with a portion of the imaging range of the third camera." [Effects of the Invention]

[0013] According to the present invention, it is possible to provide an imaging device that has good camera attachment properties, design, and distance measurement accuracy.

[0014] In particular, the embodiments of the present invention improve the ease of installation on a vehicle, the design, and the accuracy of the relative position of the camera installation. Furthermore, by performing stereoscopic vision in the overlapping area, distance measurement can be performed, and the area in which stereoscopic vision is possible can be widened. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a top view showing an example of the placement of vehicle-mounted cameras that enable 360-degree distance measurement of an autonomous vehicle. [Figure 2] FIG. 1 is a side view showing an example of the placement of a vehicle-mounted camera that enables 360-degree distance measurement of an autonomous vehicle. [Figure 3] FIG. 2 is a diagram showing an imaging range indicating a stereo viewing area. [Figure 4] 1A and 1B are diagrams illustrating an example of installation of an imaging device according to a first embodiment of the present invention. [Figure 5] 1 is a diagram showing the relationship between the camera placement positions, the imaging ranges of each camera, and overlapping areas when viewed from above the vehicle. [Figure 6A] FIG. 10 is a diagram showing a case where all camera lenses are arranged on the same plane on the sides of the vehicle in the longitudinal direction. [Figure 6B] FIG. 10 is a diagram showing the imaging range and overlapping area when the second camera is placed farther from the vehicle than the first and third cameras. [Figure 7] FIG. 10 is a diagram showing the relationship between the imaging range and overlap area between the first and third wide-field cameras. [Figure 8] FIG. 2 is a diagram showing the imaging device as seen from the front side of the vehicle. [Figure 9] FIG. 2 is a diagram showing the imaging device as seen from the rear side of the vehicle. [Figure 10] FIG. 2 is a diagram showing the imaging device as seen from above the vehicle. [Figure 11] FIG. 2 is a diagram showing the imaging device as seen from below the vehicle. [Figure 12] FIG. 10 is a side view showing the positional relationship between the imaging device and the physical mirror in the retracted state. [Figure 13] FIG. 10 is a top view showing the positional relationship with the imaging device in the physical mirror retracted state. [Figure 14] FIG. 10 is a front view showing the positional relationship with the imaging device in the physical mirror retracted state. [Figure 15] FIG. 10 is a diagram showing the exterior of a vehicle when an electronic mirror system is used. [Figure 16] FIG. 1 is a diagram showing an electronic mirror type imaging device as seen from the front of a vehicle. [Figure 17] FIG. 2 is a view of the electronic mirror type imaging device as seen from the rear of the vehicle. [Figure 18] FIG. 2 is a diagram showing an electronic mirror type imaging device as seen from above the vehicle. [Figure 19] FIG. 2 is a view of the electronic mirror type imaging device as seen from the underside of the vehicle. [Figure 20] FIG. 10 is a front view of an imaging device having a lighting function in its case. [Figure 21] FIG. 10 is a rear oblique view of the case of the imaging device when the case is provided with a lighting function. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Example]

[0017] Figures 1 and 2 are top and side views of a vehicle showing an example of the placement of on-board cameras that enable omnidirectional ranging (360-degree stereo vision area) in an autonomous vehicle. Figure 3 shows the imaging range in this example.

[0018] In the example arrangements shown in Figures 1 and 2, four sets of cameras are installed on an autonomous vehicle 1 (hereinafter simply referred to as the vehicle) for distance measurement in four directions: forward, backward, left, and right. The first set of cameras is a front camera group. As shown in the top view of Figure 1, the front camera group is made up of three cameras for forward distance measurement: a first front camera 5 (e.g., an 8MP (megapixel) camera with a narrow angle of view of 60 degrees), a second front camera 6 (e.g., an 8MP camera with a wide angle of view of 120 degrees), and a third front camera 7 (e.g., a 3MP camera with a wide angle of view of 200 degrees). The overlapping field of view of these three cameras provides a distance measurement range of 200 meters in front of the vehicle and a distance measurement range of 100 meters to the front and side of the vehicle, as shown as imaging range 10 in Figure 3.

[0019] The second camera group is a rear camera group. As shown in the top view of Figure 1, the rear camera group is made up of two cameras for rear ranging: a first rear camera 8 (e.g., an 8MP, 120-degree wide-angle camera) and a second rear camera 9 (e.g., a 3MP, 200-degree wide-angle camera). The overlapping field of view of these two cameras provides a ranging range of 50 meters behind the vehicle and 100 meters to the rear and sides, as shown in Figure 3 as imaging range 10.

[0020] The third and fourth camera groups are left and right side camera groups of the vehicle. As shown in the top view of FIG. 1, the left and right side camera groups are formed by three cameras for side ranging: a first side camera 2 (e.g., an 8MP, 120-degree wide-angle camera), a second side camera 3 (e.g., a 3MP, 200-degree fisheye camera), and a third side camera 4 (e.g., a 3MP, 120-degree wide-angle camera). The overlapping viewing areas of these three cameras provide a ranging range of 30 meters on the left and right sides of the vehicle 1, as shown in FIG. 3 as imaging range 10.

[0021] Figure 2 shows an example of the right side camera arrangement, in which, from the rear of the vehicle, a first side camera 2 (e.g., an 8MP, 120-degree wide-angle camera), a second side camera 3 (e.g., a 3MP, 200-degree fisheye camera), and a third side camera 4 (e.g., a 3MP, 120-degree wide-angle camera) are arranged.

[0022] Figure 3 shows the imaging range 10 indicated by the dotted line, which indicates the stereo field of view obtained by combining the above camera arrangement, more specifically, the "front camera group and left and right side camera group" and the "rear camera group and left and right side camera group." It shows that an appropriate distance measurement range is secured in each direction. This makes it possible to achieve all-around ranging (360-degree stereo field of view).

[0023] The imaging device according to the first embodiment of the present invention is particularly suitable for application to left and right side cameras, but this concept can also be applied to front and rear cameras. As will be described in detail below, in configuring the imaging device according to the first embodiment of the present invention, it is aimed to provide good camera installation and design, and to minimize the number of cameras. Regarding camera installation, cameras are concentrated on the side mirrors, installed in inconspicuous positions, and cameras for electronic mirrors are also used, thereby minimizing the number of cameras.

[0024] 4 is a diagram showing an example of installation of an imaging device according to the first embodiment of the present invention. The imaging device 13 is configured integrally with the physical mirror support parts 12 that attach the physical mirrors 11 on both sides of the vehicle 1 to the vehicle 1, or can be configured to be fixable to the physical mirror support parts 12. Furthermore, as will be described later in a third embodiment, in the case of a vehicle that does not have a physical mirror 11, the imaging device 13 can be fixed directly to the door of the vehicle 1.

[0025] 4 shows an example in which imaging device 13 is fixed to physical mirror support part 12 by first, second, and third screw mounting parts 17, 18, and 19. By mounting it to physical mirror support part 12, the modularized imaging device can be easily mounted to a vehicle. Furthermore, because it is fixed to physical mirror support part 12 by screw mounting parts 17, 18, and 19, rattle can be suppressed, and the effects of rattle on imaging and sensing can be suppressed.

[0026] However, no matter how the imaging device 13 is fixed, the imaging device 13 is manufactured as a so-called unit configuration in which the first side camera 2, the second side camera 3, and the third side camera 4 are arranged in this order from the rear of the vehicle, and these cameras are configured as an integrated unit. In the following description, unless otherwise necessary, the first side camera 2, the second side camera 3, and the third side camera 4 may be referred to simply as cameras 2, 3, and 4. The surfaces of these cameras 2, 3, and 4 are covered with lenses (first lens 14, second lens 15, and third lens 16), respectively.

[0027] Three lenses 14, 15, and 16 are arranged on the surface of imaging device 13, and three cameras 2, 3, and 4 are formed inside imaging device 13 by an optical system that handles light from these lenses. These cameras are fixed at predetermined positions within imaging device 3 while maintaining predetermined angles and predetermined dimensional differences, thereby ensuring predetermined imaging performance. In this way, imaging device 13 is formed as a module with lenses on the surface of the case and cameras inside the case.

[0028] By configuring the imaging device 13 as a module of multiple cameras 2, 3, and 4, or by further fixing the imaging device 13 to the vehicle 1 via the physical mirror support part 12, the problem of instability in distance measurement / recognition performance due to variations in the positions at which multiple cameras are mounted and the need for improved accuracy is eliminated.

[0029] According to the camera arrangement in Figure 4, two wide-field cameras, a first camera 2 and a third camera 4 (wide-angle cameras), are arranged at the ends in the front-to-back direction, and a fisheye-field second camera 3 (fisheye camera) is arranged sequentially between these wide-field cameras.

[0030] Furthermore, in the imaging device 13 according to Example 1 of the present invention, when the physical mirror support part 12 including the imaging device 13 is fixed to the vehicle 1, the distance between the vehicle 1 and the lens 15 of the second camera 3 is greater than the distance between the vehicle 1 and the lens 14 of the first camera 2 or the distance between the vehicle 1 and the lens 16 of the third camera 4.

[0031] In the installation example of Example 1 of the present invention, the position of lens 15 of second camera 3 may be about 1 cm higher from the side of vehicle 1 than the position of lens 14 of first camera 2, and this device is effective in improving distance measurement accuracy. How such an effect can be obtained will be explained below with reference to Figures 5, 6A, and 6B.

[0032] 5 is a diagram showing the camera arrangement as viewed from above the vehicle, the imaging range of each camera, and the relationship between the overlapping areas. As shown in this figure, lens 15 at the tip of second camera 3 is positioned farther from vehicle 1 than lenses 14, 16 at the tips of first camera 2 and third camera 4. In other words, the distance from the vehicle to the tip of second camera 3 is greater than the distance from the vehicle to the tips of the first camera and third camera.

[0033] In this figure, 20, 21, and 22 indicate the imaging ranges of the first camera 2, the second camera 3, and the third camera 4, respectively, 23 indicates the overlapping area between the first camera imaging range 20 and the second camera imaging range 21, and 24 indicates the overlapping area between the second camera imaging range 21 and the third camera imaging range 22.

[0034] With the imaging range and overlap area defined as above, Figure 6A shows a case where the lenses of all cameras 2, 3, and 4 are arranged on the side of vehicle 1, on the same plane in the longitudinal direction of the vehicle. In this figure, 25 indicates the baseline direction when the lenses of second camera 3 and third camera 4 are arranged on the same plane (same height from the side of vehicle 1). Also in this figure, 26 indicates the normal direction when the lenses of second camera 3 and third camera 4 are arranged on the same plane. Note that baseline direction 25 also shows the case where first camera 2 is arranged on the same plane, but because they are symmetrical, the imaging ranges and overlap areas of second camera 3 and third camera 4 will be described here as representatives.

[0035] In this figure, 27 is a non-stereo viewing area, and 28 is a stereo viewing area when the lenses of the second camera 3 and the third camera 4 are arranged on the same plane. In the following explanation using Figure 6A, we will explain that when all cameras 2, 3, and 4 are arranged on the same plane, non-stereo viewing area 27 is formed.

[0036] Below we will explain the operating principles of the imaging device, but first, when measuring the distance to an object using the stereo camera principle, the process of transforming the input images so that the objects in the two images are lined up on the same line is called rectification processing. Rectification processing requires image distortion correction and image rotation / projection transformation. The stereo camera principle involves determining where the same object is captured in the left and right images, and estimating a 3D point cloud from the parallax.

[0037] When measuring a 3D point cloud based on parallax, there is a problem that the 3D point cloud cannot be estimated around the base line direction 25 connecting the cameras. In reality, the cameras are occluded from each other, so the base line direction 25 is not included in the calculation of the 3D point cloud, but the calculation accuracy of the 3D point cloud deteriorates around the base line (dashed line area 27a in FIG. 6A).

[0038] 6A, the base line direction 25 of the second camera 3 and the third camera 4 becomes as shown in the figure, and the angle of view at the time of projection transformation faces the lateral direction of the vehicle. In other words, in the area close to the base line direction 25 (the area in front of the vehicle), the base line length with respect to the projection surface becomes short, making it difficult to obtain parallax, and therefore it does not become a substantial stereoscopic viewing area.

[0039] In contrast, in a stereoscopic viewing area 28 where the lenses of the second camera 3 and the third camera 4 are positioned on the same plane, the angle of view during projection transformation becomes a substantial stereoscopic viewing area, thereby improving distance measurement performance.

[0040] With respect to the normal direction 26 when the lenses of the second camera 3 and the third camera 4 are arranged on the same plane, the image of the second camera and the image of the third camera are projected and transformed in the normal direction 26 relative to the base line direction 25 of the second camera 3 and the third camera 4. This projection maximizes the parallax between the two cameras, which has the effect of improving distance measurement accuracy.

[0041] 6B shows the imaging range and overlap area when the lens of second camera 3 is positioned farther from vehicle 1 than the lenses of first camera 2 and third camera 4. Reference numeral 29 denotes the baseline direction of first camera 2 and second camera 3 when second camera 3 is positioned farther from the vehicle side, and reference numeral 30 denotes the baseline direction of second camera 3 and third camera 4 when second camera 3 is positioned farther from the vehicle side. The normals at this time are first normal 31 to baseline 29 and second normal 32 to baseline 30. As a result, a first stereo viewing area 33 and a second stereo viewing area 34 are obtained as stereo viewing areas.

[0042] 6B is clear from comparing FIG. 6A, no non-stereo viewing area 27 is formed according to the first embodiment of the present invention. Furthermore, for stereo viewing area 34 (or 33), by positioning the lens of second camera 3 outside the lens of third camera 4, the baseline direction of second camera 3 and third camera 4 becomes as shown in 30 (or 29) in the figure, and the angle of view during projection transformation faces forward of the vehicle, thereby making it possible to ensure a wide effective stereo viewing area.

[0043] In this case, with respect to normal direction 32 (or 31), the image from second camera 3 and the image from third camera 4 are projected and transformed in the normal direction relative to the baseline direction of second camera 3 and third camera 4. This projection maximizes the parallax between the two cameras, which has the effect of improving distance measurement accuracy.

[0044] Above, using Figures 6A and 6B, we have explained the effect of placing the second camera 3 in the center farther from the vehicle 1 than the first and third cameras 2 and 4 at both ends (more precisely, the position of the lens in front of the camera).

[0045] In Figures 6A and 6B, we have explained that the overlapping area between the first camera 2 and third camera 4 with a wide field of view and the second camera 3 with a fisheye field of view is the stereo viewing area, but the overlapping area between the first camera 3 and third camera 4 with a wide field of view can also be the stereo viewing area.

[0046] 7 is a diagram showing the relationship between the imaging range and overlapping area in this case, and overlapping area 35 can be obtained as the overlapping area between imaging range 20 of first camera 2 and imaging range 22 of third camera 4. The fact that overlapping area 35 can be obtained means that it can be treated as a stereo image area by subsequent signal processing and can be used as distance measurement information.

[0047] Returning to Figure 4, the first camera 2 and the third camera 4 at both ends of this imaging device 13 have their lenses 14, 16 facing almost horizontally, while the lens 15 of the second camera 3 in the center is not only positioned at a height away from the side of the vehicle 1 but also facing slightly downward (towards the ground). This makes it possible to capture images of the lower side of the vehicle. In addition, the range of stereo vision can be widened, making it possible to apply stereo vision to both the rear and front.

[0048] In addition, in Figure 4, the third camera 4, the second camera 3, and the first camera 2 are arranged in this order from the front of the vehicle in the direction of travel, with the central axis of the third lens 16 facing forward in the direction of travel relative to the vehicle, and the central axis of the first lens 14 facing backward in the direction of travel relative to the vehicle 1. By identifying the position of each camera in this way, 3D sensing of the side of the vehicle is possible.

[0049] The first embodiment of the present invention described above is a camera device that is "an imaging device 13 provided on a vehicle 1, comprising a first camera 2 having a first lens 14, a second camera 3 having a second lens 15, a third camera 4 having a third lens 16, and a case 12 that houses the first camera 2, the second camera 3, and the third camera 4 and is attached to the vehicle 1, wherein the second lens 3 is positioned further away from the vehicle than the first lens 14 and the third lens 16, and wherein a portion of the imaging range of the first camera 2 overlaps with a portion of the imaging range of the second camera 3, and a portion of the imaging range of the second camera 3 overlaps with a portion of the imaging range of the third camera 4."

[0050] By adopting this configuration, the cameras can be stored in a single case and the second camera 3 (fisheye) is positioned away from the vehicle, which increases the distance between the "baselines" of the first camera 2 (rear side) / third camera 4 (front side) and the second camera 3 (fisheye). This makes it possible to achieve both ease of installation (mountability) of multiple cameras and improved recognition performance (expansion of the parallax generation range). [Example]

[0051] In the second embodiment, a configuration example of the imaging device 13 fixed to the physical mirror 11 will be described.

[0052] First, the external configuration of the imaging device 13 fixed to the physical mirror 11 is as shown in FIG. 8 to 11 show examples of the external appearance of FIG. 4 when viewed from the front, back, top and bottom.

[0053] First, Fig. 8 shows the imaging device 13 as seen from the front side of the vehicle, and illustrates the configuration of the imaging device 13 as seen from the left side of Fig. 4. Fig. 9 shows the imaging device 13 as seen from the rear side of the vehicle, and illustrates the configuration of the imaging device 13 as seen from the right side of Fig. 4. Fig. 10 shows the imaging device 13 as seen from above the vehicle, and illustrates the configuration of the imaging device 13 as seen from the upper side of Fig. 4. Fig. 11 shows the imaging device 13 as seen from the lower side of the vehicle, and illustrates the configuration of the imaging device 13 as seen from the lower side of Fig. 4.

[0054] 8, which shows the image capture device 13 viewed from the front of the vehicle, the third lens 16 of the third camera 4 is in the foreground, and the lens 15 of the second camera 3 is visible through the cover portion 39. On the opposite side of the cover portion 39, the image capture device 13 and the physical mirror support portion 12 are in contact with each other via a plurality of contact surfaces 36, 37. The cover portion 39 covers the protruding second camera 3.

[0055] 9, which shows the image capture device 13 viewed from the rear of the vehicle, the first lens 16 of the first camera 2 is in the foreground, and the lens 15 of the second camera 3 is visible through the cover portion 39. On the opposite side of the cover portion 39, the image capture device 13 and the physical mirror support portion 12 are in contact with each other via the contact surface 38.

[0056] 10, which shows imaging device 13 viewed from above the vehicle, there is a physical mirror (here, physical mirror support part 12) at the top, and below that, arranged in this order from the rear of the vehicle, are third camera 4, second camera 3, and first camera 2. Here, when the case of imaging device 13 is viewed from above in the vertical direction of vehicle 1, second camera 3 is positioned so as to overlap with support part 12 of the physical mirror.

[0057] 11, which shows the imaging device 13 from the underside of the vehicle, there is a physical mirror (here, physical mirror support part 12) at the bottom, and above that, arranged in this order from the rear of the vehicle, are the third camera 4, the second camera 3, and the first camera 2. In particular, Figure 11 shows that the second camera, which is a fisheye lens, is installed protruding (installed away from the vehicle).

[0058] 4, the imaging device 13 is fixed to the physical mirror 11 via the physical mirror support part 12, and these integrated components are fixed to the vehicle 1 for use. For this reason, the physical mirror 11 is always disposed above the imaging device 13. The physical mirror 11 is in an open state during normal driving, or in a folded state (stored state) when the vehicle is stopped, but in either case, the distance between the tip of the physical mirror 11 and the vehicle is set to be greater than the distance between the tip of the imaging device 13 and the vehicle.

[0059] 8 to 11 mainly show the connection relationship between the imaging device 13 and the physical mirror support part 12, but in reality, the physical mirror 11 itself is installed above the physical mirror support part 12. 12 to 14 are side views, top views, and front views showing the positional relationship between the physical mirror 11 and the image capture device 13 when the physical mirror 11 is in the stored state. According to these positional and dimensional relationships, when the physical mirror 11 is in the stored state and the case of the image capture device 13 is viewed from above in the vertical direction of the vehicle, the case is positioned closer to the vehicle body than the position of the physical mirror farthest from the vehicle body, so that the electronic mirror (image capture device 13) is protected from physical impact even if the vehicle 1 scrapes against a wall or the like.

[0060] 4 and 8 to 11, the case of the imaging device 13 is integrally molded with the support portion 12 of the physical mirror 11, and the integrally molded case of the imaging device 13 is fixed facing multiple surfaces (first abutment surface 36, second abutment surface 37, third abutment surface 38) at different angles relative to the vehicle body 1 and the support portion 12 of the physical mirror 11. Generally, misalignment of the camera directly affects detection accuracy, but in this case, because it is fixed on multiple surfaces, misalignment is less likely to occur, resulting in the effect of higher detection accuracy.

[0061] 10, the second fisheye camera 3 in the middle is positioned so that it overlaps with the physical mirror support part 12. This has the effect of increasing the likelihood that the second fisheye camera 3 will be protected from physical impact even if one or both of the two wide-angle cameras 2 and 4 are hit hard enough to be destroyed. This allows image detection from the second fisheye camera 3 to continue.

[0062] 11, the second fisheye camera 4 is covered by a cover 39, which itself protrudes. This protrusion acts like a rain gutter to avoid water droplets bouncing off the vehicle body and to prevent dripping water droplets from moving toward the lens. [Example]

[0063] In the first and second embodiments, it is assumed that the imaging device 13 is installed below the physical mirror 11 and fixed to the vehicle 1.

[0064] In contrast, in Example 3, a physical mirror 11 is not installed, and only an imaging device 13 is installed outside the vehicle 1, and the stereo images obtained from this are used to display on a display device inside the vehicle, thereby adopting an electronic mirror system.

[0065] 15 is a diagram showing the appearance of a vehicle when an electronic mirror system is used, as seen from above. In this case, the physical mirror 11 is not installed in the door area, and only the image capture device 13 is installed near the installation position of the physical mirror.

[0066] The external configuration of imaging device 13 when viewed from the side of the vehicle is shown in the lower part of Fig. 15, with first camera 2, second camera 3, and third camera 4 arranged in this order from the rear of the vehicle. Fig. 16 to Fig. 19 show examples of the configuration when the external appearance of Fig. 15 is viewed from the front, back, top, and bottom.

[0067] First, Fig. 16 shows the imaging device 13 as seen from the front side of the vehicle, and illustrates the configuration as seen from arrow A in Fig. 4. Fig. 16 shows the imaging device 13 (electronic mirror) as seen from the rear side of the vehicle, Fig. 17 shows the imaging device 13 (electronic mirror) as seen from the rear side of the vehicle, Fig. 18 shows the imaging device 13 as seen from above the vehicle, and Fig. 19 shows the imaging device 13 as seen from below the vehicle.

[0068] One of the features of the configuration of this electronic mirror 13 is that, as shown particularly in Figure 18, the angle of the first camera 14 relative to the side of the vehicle is smaller than the angle of the third camera 4 relative to the side of the vehicle (part of the vehicle body is included in the field of view), and the first camera 2 can also be used as a camera for the electronic side mirror.

[0069] One of the features of the configuration of this electronic mirror 13, as shown particularly in Figures 18 and 19, is that the case of the imaging device 13 has an outer surface with multiple curvatures, and the curvature of the outer surface of the case on which the first camera 2 and the third camera 4 are located is greater than the curvature of the outer surface of the case on which the second camera 3 is located, which reduces air resistance and may also have another effect of reducing lethality in the event of a collision. [Example]

[0070] In the fourth embodiment, the imaging device is provided with a lighting function.

[0071] Fig. 20 is a view from diagonally front when the case of the imaging device is equipped with a lighting function, and Fig. 21 is a view from diagonally rear when the case of the imaging device is equipped with a lighting function. A first lighting unit 41 and a third lighting unit 43 are provided on the side of the case of the imaging device, and a second lighting unit 42 is provided on the front of the case of the imaging device.

[0072] In this way, the case has lighting units 41, 42, and 43 that illuminate the area near the case, thereby improving image quality in dark places through illumination. In addition, the lighting units can also be used as turn signals, and the lighting light from the lighting units can be near-infrared, thereby improving sensing accuracy. [Explanation of symbols]

[0073] 1: Self-driving vehicles 2: Side camera No. 1 (first camera) 3: Second side camera (second camera) 4: Third camera for side view (third camera) 5: Front camera No. 1 6: Second front camera 7: Third front camera 8: Rear camera No. 1 9: Second rear camera 10: Image capture range 11: Physical mirror 12: Physical mirror support 13: Imaging device 14: First lens 15: Second lens 16: Third lens 17, 18, 19: Mounting parts 36: First contact surface 37:Second contact surface 38: Third contact surface 41: First lighting section 42: Second lighting section 43: Third Lighting Section

Claims

1. An imaging device provided in a vehicle, a first camera having a first lens, a second camera having a second lens, a third camera having a third lens, and a case that houses the first camera, the second camera, and the third camera and is attached to the vehicle; the second lens is disposed at a position farther from the vehicle than the first lens and the third lens, an imaging device in which a portion of the imaging range of the first camera overlaps a portion of the imaging range of the second camera, and a portion of the imaging range of the second camera overlaps a portion of the imaging range of the third camera;

2. The imaging device according to claim 1 , wherein a part of the imaging range of the first camera and a part of the imaging range of the third camera overlap each other.

3. The third camera, the second camera, and the first camera are arranged in this order from the front side in the traveling direction of the vehicle, The imaging device according to claim 1 , wherein a central axis of the third lens faces forward relative to the vehicle in the traveling direction, and a central axis of the first lens faces backward relative to the vehicle in the traveling direction.

4. The imaging device according to claim 3 , wherein an angle of the first camera with respect to the side surface of the vehicle is smaller than an angle of the third camera with respect to the side surface of the vehicle.

5. 2. The imaging device of claim 1, wherein the case has an outer surface having a shape with multiple curvatures, and the curvature of the outer surface of the case on which the first camera and the third camera are arranged is greater than the curvature of the outer surface of the case on which the third camera is arranged.

6. The imaging device according to claim 1 , wherein the case has an illumination unit that illuminates the vicinity of the case.

7. The imaging device according to claim 1 , wherein the case has a mounting portion for mounting the imaging device to a support portion of a physical mirror provided on the vehicle.

8. The imaging device according to claim 7 , wherein the mounting portion has a first screw portion, a second screw portion, and a third screw portion.

9. The imaging device according to claim 7 , wherein the case is fixed to a plurality of surfaces that face the support portion of the physical mirror at different angles.

10. The imaging device according to claim 7 , wherein the second camera is disposed at a position overlapping a support portion of the physical mirror when the case is viewed from above in the vertical direction of the vehicle.

11. The imaging device according to claim 1 , wherein a cover portion of the case that covers the second camera protrudes further than cover portions that cover the first camera and the third camera.

12. 11. The imaging device according to claim 10, wherein when the physical mirror is in a retracted state, the case is positioned closer to the vehicle body than the farthest position of the physical mirror from the vehicle body when viewed from above in the vertical direction of the vehicle.

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