Imaging device and movable body

Abstract

To provide an imaging device suitable for an electric side mirror or the like.SOLUTION: An imaging device that can be installed on the lateral side of a movable body includes: an imaging unit capable of imaging a first region on the rear side of the movable body and a second region in a different direction from the rear side of the movable body; a half mirror installed at a position allowing an occupant of the movable body to visually recognize the rear side of the movable body; and a translucent member. The first region is imaged via the half mirror, and the second region is imaged via the translucent member.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to an imaging device, a moving object, and the like. [Background technology]

[0002] Conventionally, vehicles such as automobiles are equipped with side mirrors (door mirrors) for checking the left, right and rear. In recent years, however, it has become known to provide electronic side mirrors that capture images of the surroundings of the vehicle using an imaging device instead of conventional side mirrors, in order to improve visibility in bad weather and reduce blind spots, and to display images generated by the imaging device on a liquid crystal monitor or the like.

[0003] On the other hand, some drivers feel that it is difficult to grasp the angle of view and sense distance in the image of an electronic side mirror compared to a side mirror, so some side mirrors house an imaging device as an object detection means inside the side mirror, as described in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3867385 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional technology disclosed in the above-mentioned patent document, the imaging device can only capture a rearward image, i.e., it cannot capture a downward image for creating an overhead image for parking assistance or a forward image for driving assistance such as detecting an object approaching from the front of the vehicle.

[0006] Therefore, if an additional imaging device is installed to capture the above-mentioned images, the installation space becomes an issue. For example, if an additional imaging device is installed on the side of the door or on the bonnet, it will have various adverse effects on safety, design, and performance such as aerodynamic resistance.

[0007] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an imaging device suitable for an electronic side mirror or the like. [Means for solving the problem]

[0008] In order to achieve the above object, one aspect of the present invention is An imaging device that can be installed on the side of a moving object, an imaging unit capable of imaging a first area behind the moving object and a second area in a direction different from the direction behind the moving object; a half mirror arranged at a position where a passenger of the moving body can see behind the moving body; A light-transmitting member, the first area is imaged via the half mirror; The second region is imaged through the light-transmitting member. It is characterized by: Effect of the Invention

[0009] According to the present invention, an imaging device suitable for an electronic side mirror or the like can be provided. [Brief description of the drawings]

[0010] [Figure 1] 1 is a diagram showing an example of a positional relationship between a vehicle 1000 and electronic side mirrors 1R and 1L according to the first embodiment. [Diagram 2] 1 is a functional block diagram illustrating an example of the configuration of an electronic side mirror 1L according to a first embodiment. [Diagram 3] 1 is a cross-sectional view of an electronic side mirror 1L according to a first embodiment, viewed from the top surface direction. [Figure 4] 1A and 1B are diagrams illustrating an example of angle adjustment of the electronic side mirror 1 according to the first embodiment. [Diagram 5] 5 is a flowchart showing an example of a flow for adjusting the angle of the electronic side mirror 1 according to the first embodiment. [Figure 6]1 is a cross-sectional view of an electronic side mirror 1 according to a first embodiment, as viewed from the rear. [Figure 7] FIG. 11 is a functional block diagram illustrating an example of the configuration of an electronic side mirror 101 according to a second embodiment. [Figure 8] 13A and 13B are diagrams illustrating the optical characteristics of the optical system 103 according to the second embodiment. [Figure 9] 11(A) to 11(C) are diagrams showing an example of the positional relationship between a vehicle 2000 and an electronic side mirror 101L according to a second embodiment. [Figure 10] 11 is a cross-sectional view of an electronic side mirror 101L according to a second embodiment, as viewed from the top. FIG. [Figure 11] 11 is a cross-sectional view of an electronic side mirror 101L according to a second embodiment, as viewed from the rear. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment. In each drawing, the same members or elements are given the same reference numerals, and duplicated descriptions are omitted or simplified.

[0012] (Embodiment 1) An electronic side mirror 1 according to a first embodiment of the present invention will be described below with reference to Fig. 1 to Fig. 6. Fig. 1 is a diagram showing an example of the positional relationship between a vehicle 1000 and electronic side mirrors 1R and 1L according to the first embodiment.

[0013] As shown in Fig. 1, two electronic side mirrors 1R and 1L as imaging devices can be installed on the sides of a vehicle 1000 as a moving body according to this embodiment. Note that the moving body is not limited to a vehicle such as an automobile, and may be anything that is movable.

[0014] These two electronic side mirrors 1R, 1L are symmetrical and have the same functions. Therefore, the following description will be given using the electronic side mirror 1L on the left side in the traveling direction of the vehicle 1000 as an example, but unless otherwise specified, the electronic side mirror 1R on the right side will be treated as the same.

[0015] In this embodiment, the traveling direction of the vehicle 1000 (upper side in FIG. 1) is referred to as the front, and the opposite direction to the traveling direction (lower side in FIG. 1) is referred to as the rear. In addition, the right side of the electronic side mirror 1L when viewed from the front or the left side of the electronic side mirror 1R when viewed from the front is referred to as the side, the upper surface when viewed from the front (the front side of the paper) is referred to as the top direction, and the lower surface when viewed from the front (the rear side of the paper) is referred to as the bottom direction.

[0016] Fig. 2 is a functional block diagram showing a configuration example of the electronic side-mirror 1L according to embodiment 1. Note that some of the functional blocks shown in Fig. 2 are realized by causing a CPU or the like serving as a computer (not shown) included in the electronic side-mirror 1L to execute a computer program stored in a memory serving as a storage medium (not shown).

[0017] However, a part or all of these may be realized by hardware, which may be a dedicated circuit (ASIC) or a processor (a reconfigurable processor, DSP), etc.

[0018] In addition, the functional blocks shown in Fig. 2 do not have to be built in the same housing, and may be configured by separate devices connected to each other via signal paths. The above explanation regarding Fig. 2 also applies to Fig. 7.

[0019] The electronic side mirror 1L incorporates an imaging unit 2 as an object detection means. The imaging unit 2 has an optical system 3, an imaging element 4, and a processing unit 5. Since the electronic side mirror 1R has the same configuration as the electronic side mirror 1L, a description of the configuration of the electronic side mirror 1R will be omitted.

[0020] The optical system 3 has at least one lens, and forms an image of light incident from a subject on a light receiving surface (not shown) of the image sensor 4. The image sensor 4 converts the optical subject image formed by the optical system 3 into an electrical signal, and transmits it to the processing unit 5.

[0021] The processing unit 5 is, for example, a system on chip (SOC) / field programmable gate array (FPGA) or the like, and has a CPU as a computer and a memory as a storage medium.

[0022] The CPU executes computer programs stored in the memory to perform various controls of the entire system. The processing unit 5 develops the video signal acquired from the imaging element 4 and performs various image processing such as WDR (Wide Dynamic Range) correction, gamma correction, LUT (Lookup Table) processing, distortion correction, and cropping. The processing unit 5 may be provided in an information processing device located away from the vehicle 1000.

[0023] Furthermore, the electronic side-mirror 1L has an angle detection unit 6 that detects that the angle of the electronic side-mirror 1L has been adjusted. The angle detection unit 6 is, for example, an encoder provided in the angle adjustment unit of the electronic side-mirror 1L. The encoder detects the mechanical angle change of the angle adjustment mechanism with a sensor and transmits the detection information. The angle detection unit 6 transmits the detection information to the processing unit 5.

[0024] The processing unit 5 stores in advance, in an internal memory (not shown), information on the combination of the angle of the electronic side-mirror 1L and the shooting range that can be shot by the imaging unit 2 at that angle. Therefore, the processing unit 5 can calculate the necessary cropping range from the captured image based on the detection information on the angle of the electronic side-mirror 1L transmitted from the angle detection unit 6, and can perform various image processing such as cropping based on the calculation results.

[0025] The cut-out image and the like are supplied to the display unit 300 and displayed as an image. This allows the driver of the moving object to visually recognize the captured image and the cut-out image therefrom. The display unit 300 may be provided in the moving object, or in a terminal or the like for remotely controlling the moving object from the outside. The electronic side mirror 1L as the imaging device in this embodiment may be a system including the display unit 300 shown in FIG. 2.

[0026] The angle detection unit 6 may be a means other than an encoder. For example, the angle detection unit 6 may be configured to receive information on a change in the position of a part of the vehicle 1000 captured by the imaging unit 2 from the processing unit 5, calculate an angle change of the electronic side mirror 1L based on the information, and send the calculated angle change to the processing unit 5 again.

[0027] Fig. 3 is a cross-sectional view of the electronic side mirror 1L according to the first embodiment as seen from the top. Shapes that are not relevant to the description, such as screws, holes for fixing parts, electrical wiring, etc., are omitted in Fig. 3. As in Fig. 1, the upper side of Fig. 3 is the front.

[0028] As shown in FIG. 3, the electronic side mirror 1L has an optical mirror member 14 that reflects the environment behind the vehicle 1000, and a housing member 11 that has an opening at the rear for accommodating the mirror member 14.

[0029] The electronic side-mirror 1L has a plurality of imaging units 2a-2d and a holding member 12 for holding the plurality of imaging units 2a-2d. However, since the imaging unit 2d is disposed on the lower side of the electronic side-mirror 1L, it is not shown in Fig. 3. However, it is shown in Fig. 6, which will be described later. The imaging ranges 8a-8d correspond to the horizontal angles of view of the imaging units 2a-2d, respectively.

[0030] Each of the imaging units 2a to 2d has the configuration of the imaging unit 2 shown in Fig. 2. In the example shown in Fig. 3, four imaging units are provided, but the imaging unit may have an imaging unit 2a (first imaging unit) for imaging the rear (first area) of the moving body, and a second imaging unit for imaging the area other than the rear (second area). In other words, the imaging unit may be capable of imaging the first area behind the moving body and the second area in a direction other than the rear of the moving body.

[0031] The second imaging unit may include at least one of the imaging units 2b to 2d. That is, the second region may include at least one of a region in front of the moving body, a region to the side of the moving body, and a region in the direction of the road surface relative to the moving body.

[0032] Of the multiple imaging units 2a to 2c, the imaging unit 2a is disposed so that its imaging range 8a faces the rear of the electronic side mirror 1L. Furthermore, the portion of the mirror member 14 that overlaps with the imaging range 8a or the entire surface of the mirror member 14 is formed of a half mirror as a translucent member, so that the imaging unit 2a can capture an image of the rear of the vehicle 1000 by transmitting through the mirror member 14.

[0033] The imaging unit 2b is disposed so that its imaging range 8b faces forward of the electronic side mirror 1L. Furthermore, the electronic side mirror 1L has a light-transmitting member 15 disposed in a position overlapping with the imaging range 8b. The half mirror is disposed at a position to the side of the moving body where a passenger in the moving body can view the rear of the moving body, and functions as an optical side mirror.

[0034] That is, the first area is imaged through the half mirror, and the second area is imaged through the light-transmitting member. This allows the imaging unit 2b to capture an image of the area ahead of the vehicle 1000 through the light-transmitting member 15, and allows the imaging unit 2b to capture an image to be used for driving assistance such as object detection ahead of the vehicle.

[0035] The light-transmitting member 15 may be a half mirror like the mirror member 14, or may be made of other light-transmitting members, such as transparent or semi-transparent resin. When the light-transmitting member 16 is made of a half mirror, the presence of the imaging unit 2b can be hidden from the outside, which is also effective for crime prevention purposes such as parking monitoring.

[0036] The imaging unit 2c is disposed so that its imaging range 8c faces the side of the electronic side mirror 1L. Furthermore, the electronic side mirror 1L has a light-transmitting member 16 disposed at a position overlapping with the imaging range 8c.

[0037] This allows the imaging unit 2c to transmit light through the light-transmitting member 16 and capture an image of the side of the vehicle 1000, making it possible to use the imaging unit 2c as a side monitoring or proximity sensor. The light-transmitting member 16 may be made of a half mirror like the mirror member 14, or may be made of other light-transmitting members, such as transparent or semi-transparent resins. By making the light-transmitting member 16 of a half mirror, the presence of the imaging unit 2c can be hidden from the outside, making the imaging unit 2c effective for crime prevention purposes such as parking monitoring.

[0038] The electronic side-mirror 1L also has an angle adjustment mechanism 7. The angle adjustment mechanism 7 is composed of, for example, a vertical rotation shaft and a drive motor (not shown), and allows the driver of the vehicle to adjust the angle to an optimal angle when checking behind the vehicle using the mirror member 14 of the electronic side-mirror 1L.

[0039] Furthermore, when parking, the electronic side mirror can be rotated 90 degrees counterclockwise from the state shown in Fig. 3 to a stored state. However, when the angle of the electronic side mirror 1L is adjusted by the angle adjustment mechanism 7, there is a possibility that the imaging range 8 of the imaging unit 2 will change in conjunction with the angle change.

[0040] Hereinafter, a case where the angle of the electronic side mirror 1L is adjusted by the angle adjustment mechanism 7 will be described with reference to Fig. 4 and Fig. 5. Fig. 4(A) and (B) are diagrams for explaining an example of angle adjustment of the electronic side mirror 1L according to the first embodiment, and illustrate changes that occur when the electronic side mirror 1L is horizontally rotated using the angle adjustment mechanism 7.

[0041] Figure 4(A) shows, for example, the initial state of the electronic side mirror 1L, and Figure 4(B) shows a state in which the mirror member 14 has been rotated, for example, 10 degrees counterclockwise around the rotation axis of the angle adjustment mechanism 7 from the initial state, and the imaging ranges 8a to 8c have been rotated 10 degrees counterclockwise.

[0042] Meanwhile, the horizontal angle of view cut out by the processing unit 5 is shown as a schematic representation of cut-out ranges 9a to 9c. In this embodiment, when the electronic side mirror 1L is rotated counterclockwise as shown in Fig. 4(B), the cut-out range 9a for the imaging range 8a does not change, but the cut-out ranges 9b and 9c for the imaging ranges 8b and 8c change.

[0043] Fig. 5 is a flowchart showing an example of a flow when adjusting the angle of the electronic side mirror 1L according to the embodiment 1, and Fig. 5 shows an operation flow of the processing unit 5 when the angle is changed from Fig. 4(A) to Fig. 4(B). Note that the operation of each step of the flowchart in Fig. 5 is performed sequentially by the CPU as a computer in the processing unit 5 executing a computer program stored in the memory.

[0044] First, in the initial state of Fig. 4(A), cut-out ranges 9a to 9c are cut out from the imaging ranges 8a to 8c, respectively. These cut-out ranges 9 are adjusted in advance to be optimal for each application (for example, forward monitoring, side monitoring, rear monitoring). In addition, the cut-out ranges 9 are linked to the initial angle of the electronic side mirror 1L and stored in a memory (not shown) in the processing unit 5 in advance.

[0045] 4(A), the driver operates an operation unit (not shown) to adjust the mirror member 114 of the electronic side-mirror 1L to an optimal angle for checking behind depending on changes in the external environment, etc. As a result, the electronic side-mirror 1L is rotated counterclockwise by, for example, 10 degrees. When the electronic side-mirror 1L is rotated, in step S1, the CPU in the processing unit 5 receives detection information related to the rotation angle detected by the sensor from the angle detection unit 6.

[0046] Next, in step S2, the CPU of the processing unit 5 calls up from the internal memory information on the combination of the angle of the electronic side mirror 1L and the imaging range that can be captured by the imaging unit 2 at that angle. Then, based on the information read from the memory and the detection information received in step S1, it is determined whether the imaging range 8 has changed with respect to the vehicle body before and after the rotation.

[0047] As shown in Fig. 4, the imaging ranges 8a to 8c change in conjunction with the change in the angle of the entire electronic side mirror 1L. If NO in step S2, the flow in Fig. 5 ends.

[0048] Next, in step S3, the CPU of the processing unit 5 determines whether the changes in each of the imaging ranges 8a to 8c that occurred in S2 are acceptable. This determination is made based on whether the changes in the imaging ranges 8 match the purpose of using the image.

[0049] For example, the cut-out range 9a cut out from the image captured in the imaging range 8a is used for rearward confirmation. Therefore, when the driver adjusts the angle for the purpose of rearward confirmation, it is desirable that the imaging range 8a and the cut-out range 9a also change in conjunction with each other. In other words, it is determined that the change in the imaging range 8a is acceptable. In that case, the flow of FIG. 5 ends without changing the cut-out range.

[0050] On the other hand, it is not desirable for the cut-out range 9b cut out from the imaging range 8b and the cut-out range 9c cut out from the imaging range 8c to change in conjunction with the change in angle for the purpose of rearward confirmation, since the purpose of using the image is not rearward confirmation. Therefore, the result of the determination in step S3 is NO, and the process proceeds to step S4.

[0051] In step S4, the CPU of the processing unit 5 determines how much the imaging ranges 8b and 8c have changed based on the combination information of the angle of the electronic side mirror 1L and the imaging ranges of the imaging units 2b and 2c and the detection information received in step S1. Then, in step S5, the CPU of the processing unit 5 reduces the effect of the angle change by moving the clipping ranges 9b and 9c in a direction that cancels the changes in the imaging ranges 8b and 8c.

[0052] In this manner, this embodiment has an angle adjustment mechanism that rotates relative to the moving body, and the processing unit 5 cuts out a partial area from the image captured by the imaging device according to the amount of rotation of the imaging device.

[0053] That is, in the example shown in Fig. 4(B), the entire electronic side mirror 1L rotates 10 degrees counterclockwise, and the imaging ranges 8b and 8c also rotate about 10 degrees. Therefore, by moving the cut-out ranges 9b and 9c so that they rotate about 10 degrees clockwise, the effect of the angle change is reduced and the display angle of view is maintained. However, "maintaining the display angle of view" as used here is not limited to maintaining the display angle of view to be exactly the same. It is acceptable for the display angle of view to have an error.

[0054] Incidentally, the electronic side mirror 1L may have a mechanism for tilt rotation, for example, in addition to the horizontal rotation (pan rotation) as illustrated in FIG. 4, and in the case of tilt rotation, the same processing as in FIG. 5 may be performed.

[0055] Furthermore, if the angle adjustment mechanism of the electronic side-mirror 1L does not rotate the entire electronic side-mirror 1L, but is a mechanism that independently drives only the mirror member 14, there is no effect on the imaging range 8. Therefore, in step S2, it is determined that there is no change in the imaging range 8 before and after the rotation, and the above-mentioned change in the cropping range is not performed.

[0056] However, if the imaging unit 2 is configured to be fixed to the mirror member 14, rotating only the mirror member 14, rather than rotating the entire electronic side mirror 1L, may affect the imaging range 8. In that case, it is desirable for the processing unit 5 to change the cropping range as necessary.

[0057] FIG. 6 is a cross-sectional view of the electronic side mirror 1L according to the first embodiment as seen from the rear, with the lower side referred to as the bottom direction and the left side referred to as the side direction.

[0058] As shown in FIG. 6, the imaging range 8d of the imaging unit 2d of the electronic side mirror 1L is disposed so as to include the bottom surface direction of the electronic side mirror 1L, in particular the tire periphery including the front wheels (not shown) of the vehicle 1000 and the road surface.

[0059] Furthermore, the electronic side mirror 1L has a light-transmitting member 17 at a position overlapping with the imaging range 8d. This allows the imaging unit 2d to transmit the light-transmitting member 17 and capture an image of the bottom surface of the vehicle 1000, which can be used to create an overhead image for parking assistance or the like.

[0060] The light-transmitting member 17 may be made of a half mirror like the mirror member 14, or may be made of other light-transmitting members, such as transparent or semi-transparent resin. Furthermore, by making the light-transmitting member 17 of a half mirror, the presence of the imaging unit 2d can be hidden from the outside, which is also effective for crime prevention purposes such as parking monitoring.

[0061] Like the imaging ranges 8a to 8c, the imaging range 8d may also change in conjunction with the angle change when the angle of the electronic side mirror 1L is adjusted by the angle adjustment mechanism 7. For this reason, it is desirable for the processing unit 5 to change the cut-out range as necessary.

[0062] (Embodiment 2) In the first embodiment, a configuration has been described in which a plurality of imaging units 2 are arranged in the electronic side mirror 1L to reduce blind spots. In the second embodiment, a configuration example in which one wide-angle imaging unit 102 is arranged in the electronic side mirror 101L will be described.

[0063] Note that the description of the same points as in the first embodiment will be omitted or simplified. In the following, the description will be given taking as an example the electronic side mirror 101L on the left side in the traveling direction of the vehicle 2000. However, the right side electronic mirror 101R has a similar configuration to the electronic side mirror 101L and is symmetrical to the electronic side mirror 101L, and therefore the description will be omitted.

[0064] An electronic side mirror 101L according to embodiment 2 of the present invention will be described below with reference to Fig. 7 to Fig. 11. Fig. 7 is a functional block diagram showing an example of the configuration of the electronic side mirror 101L according to embodiment 2. The electronic side mirror 101L has a built-in imaging unit 102 as an object detection means, and the imaging unit 102 has an optical system 103, an imaging element 104, and a processing unit 105.

[0065] The optical system 103 has at least one lens, and forms an optical image by making light incident from a subject incident on a light receiving surface (not shown) of the image sensor 104. The image sensor 104 converts the optical subject image formed by the optical system 103 into an electrical signal and transmits it to the processing unit 105.

[0066] Furthermore, the electronic side-mirror 101L also has an angle detection unit 106 that detects the angle when the angle of the electronic side-mirror 101L is adjusted. The angle detection unit 106 is, like the angle detection unit 6 in the first embodiment, for example, an encoder or the like provided in an angle adjustment unit of the electronic side-mirror 101L, and details of the angle adjustment are the same as in the first embodiment, so they will not be described. The display unit 300 is also the same as in the first embodiment, so a description thereof will be omitted.

[0067] Next, a detailed description will be given of the optical characteristics of the optical system 103 of the imaging unit 102. Figures 8A and 8B are diagrams for explaining the optical characteristics of the optical system 103 according to the second embodiment, and Figure 8A is a diagram showing the image height y of the optical system 103 at each half angle of view on the light receiving surface of the imaging element in the form of contour lines.

[0068] 8B is a diagram showing projection characteristics indicating the relationship between image height y, which is the imaging height, and half angle of view θ of the optical system 103. In Fig. 8B, the horizontal axis indicates half angle of view (angle between the optical axis and the incident light) θ, and the vertical axis indicates imaging height (image height) y on the light receiving surface (image plane) of the imaging unit 102.

[0069] 8B, the optical characteristic of the optical system 103 is that its projection characteristic y(θ) differs between a region where the half angle of view θ is small (near the optical axis) and a region where the half angle of view θ is large (region away from the optical axis). In other words, when the increase in image height y per unit half angle of view θ (i.e., the number of pixels per unit angle) is called resolution, the resolution differs depending on the region.

[0070] This local resolution can be expressed as the differential value dy(θ) / dθ of the projection characteristic y(θ) at the half angle of view θ. In other words, the greater the gradient of the projection characteristic y(θ) in Fig. 8(B), the higher the resolution. Also, the greater the interval between the image heights y at each half angle of view on the contour lines in Fig. 8(A), the higher the resolution.

[0071] In this embodiment, when the half angle of view θ is less than a predetermined half angle of view θa, the area near the center (where the half angle of view θ is less than the predetermined half angle of view θa) formed on the light receiving surface of the sensor is called the low-resolution area 20c, and the outer area where the half angle of view θ is equal to or greater than the predetermined half angle of view θa is called the high-resolution area 20b.

[0072] Also, 20a indicates the entire imaging range (full angle of view). The low-resolution area 20c is a high distortion area, and the high-resolution area 20b is a low distortion area. In the embodiment, the low-resolution area 20c and the high-resolution area 20b of the optical system 103 are configured concentrically, but they do not have to be concentrically. For example, each area may have a distorted shape.

[0073] In addition, the center of gravity of the low-resolution region 20c and the center of gravity of the high-resolution region 20b do not have to coincide with each other, and furthermore, they may be offset from the center of the light receiving surface. In the optical system of this embodiment, it is sufficient that the low-resolution region 20c is formed on the central side of the light receiving surface of the image sensor, and the high-resolution region 20b is formed on the peripheral side of the light receiving surface.

[0074] In this way, the optical system in the second embodiment forms an optical image with a first resolution in the central region of the light receiving surface of the image sensor, and forms an optical image with a second resolution higher than the first resolution in the peripheral region around the central region. Also, the optical system forms an optical image of at least the first region in the peripheral region.

[0075] The optical system 103 of this embodiment is configured to satisfy the following formula 1, where f is the focal length, θ is the half angle of view, y is the image height on the image plane, y(θ) is a projection characteristic that represents the relationship between the image height y and the half angle of view θ, and θmax is the maximum half angle of view of the optical system.

[0076] 0.2<2×f×tan(θmax / 2) / y(θmax)<0.92 (Formula 1) In an optical system having such optical characteristics, the magnification in the radial direction with respect to the optical axis can be adjusted by adjusting the projection characteristic y(θ).

[0077] This makes it possible to control the aspect ratio in the radial and circumferential directions relative to the optical axis, making it possible to obtain a high-resolution image with little distortion in the peripheral areas despite a wide angle of view, unlike conventional fisheye lenses.

[0078] 9(A) to 9(C) are diagrams showing an example of the positional relationship between a vehicle 2000 and an electronic side mirror 101L according to the second embodiment, and FIG. 9(A) is a perspective view showing the vehicle 2000 according to this embodiment.

[0079] Also, Fig. 9(B) is an enlarged view of the periphery of the electronic side mirror 101L in Fig. 9(A), and Fig. 9(C) is an exploded perspective view of the electronic side mirror 101L in Fig. 9(B). Note that shapes that are not relevant to the description, such as screws, holes for fixing parts, and electrical wiring, are omitted in Figs. 9(A) to (C).

[0080] 9(A) to 9(C), the electronic side mirror 101L has an optical mirror member 114 that reflects the environment behind the vehicle 2000, and a base member 111 that is rotatably attached to the vehicle 2000 by a shaft portion 107 for an angle adjustment mechanism. The electronic side mirror 101L also has a cover 112 made of a light-transmitting member, an imaging unit 102, a holding member 116 for holding the imaging unit 102, and the like.

[0081] 10 is a cross-sectional view of the electronic side mirror 101L according to embodiment 2, as viewed from the top. The entire imaging range 30a diagrammatically shows the horizontal angle of view of the imaging unit 102. The high-resolution imaging range 30b is the range imaged by the high-resolution region 20b of the imaging unit 102, and the low-resolution imaging range 30c is the range imaged by the low-resolution region 20c of the imaging unit 102.

[0082] Moreover, the entire imaging range 30a corresponds to the entire imaging range (full angle of view) 20a of the imaging unit 102. Also in Fig. 10, like Fig. 1, the upper side is the front.

[0083] The imaging unit 102 is disposed so that the mirror member 114 formed as a half mirror overlaps with the rear high-resolution imaging range 30b. Therefore, the imaging unit 102 is configured to be able to capture an image of the rear of the vehicle 2000 through the mirror member 114 in the rear high-resolution imaging range 30b.

[0084] Furthermore, the electronic side mirror 101L has a cover 112 made of a light-transmitting member arranged in an area overlapping with the forward high-resolution imaging range 30b. This allows the imaging unit 102 to transmit light through the cover 112 and capture an image of the area in front of the vehicle 2000 in the forward high-resolution imaging range 30b. In other words, the second area includes an area in front of the moving object, and the optical system forms an optical image of at least the area in front of the moving object in the second area in the peripheral area.

[0085] Therefore, the imaging unit 102 can use the high-resolution imaging range 30b in front for driving assistance such as detecting an object approaching from the front. The cover 112 may be made of a half mirror like the mirror member 114, or may be made of other light-transmitting members such as transparent or semi-transparent resins.

[0086] Furthermore, by configuring the cover 112 with a half mirror, the presence of the imaging unit 102 can be hidden from the outside, which is also effective for crime prevention purposes such as parking surveillance.

[0087] The entire imaging range 30a of the imaging unit 102 also includes the sides of the electronic side mirror 101L. Furthermore, the cover 112 made of a translucent member is disposed so as to include the range of the entire imaging range 30a of the imaging unit 102 that overlaps with the areas to the sides of the electronic side mirror 101L.

[0088] That is, the second region includes a region on the side of the moving object, and the optical system forms an optical image of at least the region on the side of the moving object in the second region in the central region. This allows the imaging unit 102 to capture an image of the side of the vehicle 2000 through the cover 112, and can be used for side monitoring or as a proximity sensor.

[0089] FIG. 11 is a cross-sectional view of the electronic side mirror 101L according to the second embodiment as seen from behind, and like FIG. 6, the lower side is the bottom direction and the left side is the side direction.

[0090] The imaging unit 102 is disposed in the bottom direction such that the high-resolution imaging range 30b includes the tire periphery including the front wheels and the road surface of the vehicle 2000 (not shown). Furthermore, as shown in Fig. 11, the electronic side mirror 101L has a cover 112 formed of a light-transmitting member disposed in an area overlapping with the high-resolution imaging range 30b in the bottom direction.

[0091] That is, the second region includes a region in the direction of the road surface relative to the moving object, and the optical system forms an optical image of at least the region in the direction of the road surface in the second region in the peripheral region. Also, the optical system forms an optical image of at least one of the front wheels or the rear wheels of the moving object and the road surface, which are included in the second region, in the peripheral region.

[0092] This allows the imaging unit 102 to transmit through the cover 112 and capture an image of the bottom surface of the vehicle 2000, which can be used to create an overhead image for parking assistance, etc. Furthermore, the imaging unit 102 can transmit through the cover 112 and capture an image of the top surface of the vehicle 2000.

[0093] 10 and 11, in the second embodiment, one light-transmitting member (cover 112) is arranged in an area that overlaps at least the front, side, and bottom directions of the entire imaging range 30a of the imaging unit 102. However, similar to the first embodiment, a configuration in which separate windows of a light-transmitting member are arranged in each direction may also be used.

[0094] The present invention has been described above in detail based on its preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications and combinations of the above embodiments are possible based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0095] The moving object in the embodiment may be any moving device that moves, such as an automobile, a train, a ship, or an airplane. The present invention can also be applied to a case where a moving object is remotely controlled. The above embodiment includes the following combinations.

[0096] (Configuration 1) An imaging device that can be installed on the side of a moving body, comprising: an imaging unit capable of imaging a first area behind the moving body and a second area in a direction different from the rear of the moving body; a half mirror positioned at a position where a passenger on the moving body can view the rear of the moving body; and a translucent member, wherein the first area is imaged through the half mirror and the second area is imaged through the translucent member.

[0097] (Configuration 2) The imaging device described in Configuration 1, characterized in that the imaging unit has a first imaging unit that images the first area and at least one second imaging unit that images the second area, and the second area includes at least one of an area in front of the moving body, an area to the side of the moving body, and an area in the direction of the road surface relative to the moving body.

[0098] (Configuration 3) The imaging device described in configuration 1 or 2, wherein the imaging unit has an imaging element and an optical system that forms an optical image on the light receiving surface of the imaging element, the optical system forms an optical image of a first resolution in a central region of the light receiving surface of the imaging element, and forms an optical image of a second resolution higher than the first resolution in a peripheral region around the central region, and the optical system forms an optical image of at least the first region in the peripheral region.

[0099] (Configuration 4) The imaging device described in Configuration 3, characterized in that the second region includes a region in front of the moving body, and the optical system forms an optical image of at least the region in front of the moving body in the second region in the peripheral region.

[0100] (Configuration 5) The imaging device described in Configuration 4, characterized in that the second region includes a lateral region of the moving body, and the optical system forms an optical image of at least the lateral region of the moving body in the second region in the central region.

[0101] (Configuration 6) The second area includes an area in a direction of a road surface relative to the moving body, The imaging device according to any one of configurations 3 to 5, wherein the optical system forms an optical image of at least an area of ​​the second area in a direction toward the road surface in the peripheral area.

[0102] (Configuration 7) The imaging device described in Configuration 6, characterized in that the optical system forms an optical image of at least one of the front wheels or rear wheels of the moving body and the road surface, which are included in the second area, in the surrounding area.

[0103] (Configuration 8) The imaging device described in any one of configurations 1 to 7, further comprising: a processing unit having an angle adjustment mechanism that rotates relative to the moving body and that cuts out a portion of an area from an image captured by the imaging device according to the amount of rotation.

[0104] (Configuration 9) A moving body comprising: the imaging device according to any one of configurations 1 to 8; and a display unit that displays an image captured by the imaging device.

[0105] In order to realize a part or all of the control in the above-mentioned embodiment, a computer program that realizes the functions of the above-mentioned embodiment may be supplied to an imaging device or the like via a network or various storage media. Then, a computer (or a CPU, MPU, or the like) in the imaging device or the like may read and execute the program. In this case, the program and the storage medium storing the program constitute the present invention. [Explanation of symbols]

[0106] 1: Electronic side mirror 2: Imaging unit 3:Optical system 4: Image sensor 5: Processing section 6: Detection methods 7: Angle adjustment mechanism

Claims

1. An imaging device that can be installed on the side of a moving object, an imaging unit capable of imaging a first area behind the moving object and a second area in a direction different from the rear of the moving object; a half mirror arranged at a position where a passenger of the moving body can see behind the moving body; A light-transmitting member, the first area is imaged via the half mirror, The second region is imaged through the light-transmitting member.

1. An imaging device comprising:

2. the imaging unit includes a first imaging unit that images the first region and at least one second imaging unit that images the second region; The second region includes at least one of a region in front of the moving body, a region to the side of the moving body, and a region in a direction of a road surface relative to the moving body.

2. The imaging device according to claim 1 .

3. the imaging unit includes an imaging element and an optical system that forms an optical image on a light receiving surface of the imaging element; the optical system forms an optical image having a first resolution in a central region of the light receiving surface of the image sensor, and forms an optical image having a second resolution higher than the first resolution in a peripheral region around the central region; The optical system forms an optical image of at least the first area in the peripheral area.

2. The imaging device according to claim 1 .

4. the second area includes an area in front of the moving object, 4. The imaging device according to claim 3, wherein the optical system forms an optical image of at least a region in front of the moving object in the second region in the peripheral region.

5. the second region includes a region on a side of the moving object, 5. The imaging device according to claim 4, wherein the optical system forms an optical image of at least a lateral area of ​​the moving object in the second area in the central area.

6. the second region includes a region in a direction of a road surface relative to the moving object, 4. The imaging device according to claim 3, wherein the optical system forms an optical image of at least a region of the second region in a direction toward the road surface in the peripheral region.

7. 7. The imaging device according to claim 6, wherein the optical system forms an optical image of at least one of the front wheels or rear wheels of the moving object and a road surface, which are included in the second area, in the peripheral area.

8. An angle adjustment mechanism that rotates relative to the moving body, 2. The imaging device according to claim 1, further comprising a processing unit that cuts out a partial area from the image captured by the imaging device in accordance with the amount of rotation.

9. An imaging device according to any one of claims 1 to 8, and a display unit that displays an image captured by the imaging device.

Images