Imaging System for Non-Positive-Direction Photography and Method for Setting Imaging System

Abstract

The present invention discloses an imaging system for non-forward shooting and a method for setting the imaging system. The imaging system includes a camera body, an image collection unit, and an imaging lens. The image collection unit and the imaging lens are respectively attached to the front end and the rear end of the camera body. The camera body has a first angle θ that is inclined in a first direction with respect to a reference direction. The image collection unit and the imaging lens respectively have a second angle α and a third angle β that are inclined in a direction opposite to the inclination direction of the camera body with respect to the main axis of the camera body. The second angle α and the third angle β are different from each other. The present invention can clearly capture a scene within a wider depth of field range on the side or below of a target without perspective distortion, and can provide a better viewing range for people.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims priority based on Chinese Patent Application No. 202210732008.1, titled "Imaging System for Non - forward Shooting and Method for Setting an Imaging System", filed on June 26, 2022.

[0002] The present invention relates to the field of imaging, and in particular, to a high - resolution imaging system with a deeper depth of field and no perspective distortion.

Background Art

[0003] When taking pictures, in the normal shooting method, the camera faces the shooting area directly, and both the focal plane and the object plane are parallel to the image plane. This shooting method is called "forward shooting". However, in some specific application scenarios, this "forward shooting" cannot bring the optimal shooting and application effects. For example, in the shooting process of imaging systems in squares, stations, and vehicles, when this forward shooting is adopted, the perspective distortion is serious, so the effect is not ideal.

[0004] For example, in the case of in - vehicle imaging systems, with the development of electronic imaging technology, more and more vehicle rear - view mirrors are equipped with auxiliary imaging devices. Through the rear camera or other cameras, the scene captured by the camera is displayed to the driver through the screen, thereby improving the field of view range and the sharpness of the field of view observed by the driver.

[0005] The focusing method of the imaging device based on optics determines its limited depth - of - field range, and the sum of the front depth of field and the rear depth of field cannot meet the needs of the deep depth of field of in - vehicle electronic rear - view mirrors. When the depth of field is insufficient, the distribution of the sharpness of the image becomes non - uniform, local image blurring occurs, and the gap between the sharpness of the reflected image of the glass mirror becomes very large.

[0006] In addition, all conventional in-vehicle rearview imaging systems adopt a design in which the optical axis of the lens and the center of the photosensitive image plane are coaxial, and the focal plane and the image plane are parallel. This design can ensure that the object plane behind the vehicle can form a clear image on the image collection unit. However, the most distinct position of this image must be located at the center position of the image. That is, in the lens design of conventional in-vehicle rearview systems, the image quality at the center is excellent, and it is inevitable that the image quality at the edge is relatively poor. In fact, during vehicle driving, the area that the driver needs to pay the most attention to on the glass rearview mirror (electronic display) is not the center position, but 60-80% above the center point of the glass rearview mirror (electronic display) and adjacent to the vehicle body side. The technology of conventional imaging systems has not yet solved this problem.

[0007] As shown in FIG. 1, the video camera lens images in a circular shape, and the distortion caused by the wide-angle lens is barrel distortion. In order to make the distortion directions of the imaging distortion of the electronic video camera and the distortion caused by the glass mirror coincide, the image must be corrected by software. In FIG. 1, the left side is the imaging principle of the glass mirror, and the right side is the imaging principle of the electronic video camera.

[0008] In actual installation, if the position of the video camera is downward and outward, the perspective distortion is too large, and if there is too much correction by software, pixels will be lost, thereby reducing the resolution of the image. As shown in FIG. 2, in FIG. 2, the left side is the imaging result of the shooting method with the image collection unit in the center, and the right side is the imaging result of the shooting method with the image collection unit offset.

[0009] The reflection imaging of a normal glass rearview mirror has almost no perspective distortion and only affects the observation range in relation to the eye point observation. In contrast, the imaging of an electronic video camera is affected by the installation position, so perspective distortion appears, and during application, the perspective distortion must be corrected by software, but this will cause a change in the magnification of the object.

[0010] For example, in order to maintain the highest sharpness and clarity on the vehicle body side within the display screen, the Skyline is imaged in the 60 - 80% region in the vertical direction of the display. Therefore, the optical axis of the video camera lens must be maintained parallel to the central axis of the vehicle, and the video camera must be mounted so as to tilt towards the ground. In this way, since half of the images collected by the video camera are blocked by the vehicle body and wasted, the effective screen pixels collected by the video camera cannot be effectively utilized. When the video camera tilts outside the vehicle body, it causes perspective distortion of horizontal convergence of the image. When the video camera tilts downward, it causes perspective distortion of vertical convergence. In the current mounting and use, since both of these tilting mounting methods must exist, in the images collected by the video camera, these two perspective distortions are intertwined and significantly appear. The images must be trimmed and corrected by software in the later stage. Therefore, the huge amount of software coding and the computing power of the chip greatly increase the comprehensive cost, cause serious pixel loss, and reduce the observation field of view, thus affecting the image quality. As shown in Figure 3, it shows the comparison of the images before and after correction by the software of the prior art. Since the image quality is lost by about 40% after correction, the conventional imaging system has not yet solved this problem. Summary of the Invention Problems to be Solved by the Invention

[0011] In view of the above problems, an object of the present invention is to provide an imaging system with a deep depth of field, a wide clear range, and solved perspective distortion. Also, when applying it to an in - vehicle rear - view system, it can capture the position near the boundary line between the ground and the sky more clearly. Means for Solving the Problems

[0012] Specifically, the present invention provides an imaging system for non-forward shooting. The imaging system includes a camera body, an image collection unit, and an imaging lens. The front end of the camera body is a camera barrel. The imaging lens is mounted within the camera barrel. The image collection unit is mounted at the rear end of the camera body. The camera barrel has a first angle θ that inclines in a first direction with respect to a reference direction. The imaging lens and the image collection unit respectively have a second angle α and a third angle β that incline in a direction opposite to the inclination direction of the camera barrel with respect to the main axis of the camera barrel.

[0013] Preferably, the second angle α and the third angle β are different from each other.

[0014] Preferably, the third angle β is larger than the second angle α such that the plane where the image collection unit and the imaging lens are located intersects on one side of the inclination direction of the camera barrel to form an acute angle.

[0015] Preferably, the imaging lens has a horizontal translation or offset in a second direction with respect to the main axis of the camera barrel, or the image collection unit has a horizontal translation or offset in a direction opposite to the second direction with respect to the main axis of the camera barrel. The second direction is perpendicular to the first direction and the main axis of the camera barrel, faces the subject, and the image collection unit and the imaging lens have a deflection angle γ in the second direction.

[0016] Preferably, the first angle θ is 6 to 14 degrees, the second angle α is 6 to 14 degrees, and the third angle β is 8 to 17 degrees.

[0017] Preferably, the imaging system is an in-vehicle imaging system for attachment to a target vehicle. The imaging system is mounted on the side of the target vehicle. The first direction is a vertically downward direction, and the second direction is a direction away from the vehicle body.

[0018] Preferably, the imaging system includes a plurality of imaging structures including an image collection unit, an imaging lens, and a camera body, and is respectively mounted on both sides of the vehicle.

[0019] Preferably, the imaging system is mounted at a position higher than the target imaging area.

[0020] Preferably, the object-side focus of the imaging lens is located behind the side of the target vehicle, and the plane passing through the object-side focus intersects with the intersection line of the plane where both the image collection unit and the imaging lens are located to form an object-side focal plane S. Here, the third angle β and the second angle α satisfy the relationship of arctan(β - α) = f / (H - h), where H is the height of the center of the imaging lens from the ground, f is the focal length of the imaging lens, and h is the preset height of the object-side focal plane S from the ground.

[0021] On the other hand, the present invention provides a method for setting the structure of an imaging system. The imaging system includes a camera body, an image collection unit, and an imaging lens. The front end of the camera body is a camera barrel. The method includes the following steps. The step of mounting the imaging lens in the camera barrel, The step of mounting the image collection unit at the rear end of the camera body, The step of mounting the imaging system so that the main axis of the camera barrel is inclined at a first angle θ with respect to a reference direction, and The step of setting the image collection unit and the imaging lens so that they respectively have different second angles α and third angles β that are inclined in directions opposite to the inclination direction of the main axis of the camera barrel with respect to the main axis of the camera barrel.

[0022] Preferably, the third angle β is larger than the second angle α such that the plane where the image collection unit and the imaging lens are located intersects to form an acute angle.

[0023] Preferably, the image acquisition unit has a horizontal offset in a second direction with respect to the main axis of the camera barrel, the second direction is perpendicular to the first direction and the main axis of the camera barrel, and the image acquisition unit and the imaging lens have a deflection angle in a third direction, and the third direction is opposite to the second direction.

[0024] Preferably, the first angle θ is 6 to 14 degrees, the second angle α is 6 to 14 degrees, and the third angle β is 8 to 17 degrees.

[0025] Preferably, the first angle θ may be 7, 8, 9, 10, 11, 12, 13 degrees, the second angle α may be 7, 8, 9, 10, 11, 12, 13 degrees, and the third angle β may be 8, 9, 10, 11, 12, 13, 14, 15, 16 degrees.

[0026] In addition, the "non - forward - direction shooting" referred to in the present invention means inclined shooting, that is, the case where the target shooting area is not parallel to the image plane of the image sensor. For example, when shooting downward from above a square, the target shooting area is as wide as possible on the plane of the entire square. However, in order to maintain "forward - direction shooting", it is necessary to shoot vertically downward from above, which requires an ultra - wide - angle camera and has very high requirements for the height of the camera, so it is difficult to achieve. Therefore, only the method of shooting downward at an inclination can be adopted.

[0027] When the video camera is inclined downward, the plane (COMS) of the image acquisition device and the focal plane of the imaging lens are in a parallel state, the people (the subject plane) in the square are in a vertical state, and the image plane and the focal plane formed by the image acquisition device are not parallel. At this time, since the head and feet are not in the same focal plane, the sharpness has a difference, the person has a perspective distortion, and the width of the head is distorted proportionally to the forward - direction shooting.

[0028] When the technology of the present invention is adopted, the image plane and the focal plane of the image acquisition device are tilted backward simultaneously, and together with the person (subject plane), by calculating the mounting height, the image plane, the focal plane, and the subject plane are adjusted to intersect in a straight line, so that the sharpness of the head and feet is consistent, and it is possible to realize that no perspective distortion of the person's head occurs.

[0029] The "reference direction" referred to in the present invention can be set according to the shooting needs. For example, in the case of the above-described downward-tilt shooting, the reference direction is the horizontal direction. However, when shooting toward the upper side part, the reference direction may be the vertical direction. In the in-vehicle camera scenario, the horizontal rearward direction is selected as the reference direction.

[0030] The "first direction" referred to in the present invention refers to the direction in which there are more subjects on one side of the reference direction. In the in-vehicle camera scenario, the first direction is the vertical direction, particularly the vertically downward direction.

[0031] The "second direction" referred to in the present invention refers to the direction that is substantially perpendicular to the first direction and the main axis direction of the camera barrel and is directed toward the direction in which there are more subjects. In the in-vehicle camera scenario, the second direction is the direction that is substantially horizontal and directed outward from the vehicle body, away from the vehicle body.

[0032] Note that the second angle may be 0, and the third angle is not 0.

[0033] When the imaging system of the present invention is applied to an in-vehicle imaging system, the imaging system may be divided into two on the left and right and installed on both sides of the vehicle in an axially symmetric manner. Moreover, regarding the positional relationship of the camera barrel, the image acquisition unit, and the imaging lens referred to in the present invention, they may be fixed by fixing them to the imaging system, or may be attached to the imaging system by an adjustable attachment method. The "downward tilt" in the in-vehicle imaging system means that the shooting direction of the camera with respect to the horizontal direction is tilted downward. The "away from" direction from the vehicle body means that, standing at the viewpoint of the camera, in order to shoot less of the vehicle body and more rearward subjects, the camera is tilted and rotated outward with respect to the vehicle cabin side wall of the vehicle body.

Advantages of the Invention

[0034] The imaging system of the present invention can provide a clearer image with a deeper depth of field and no perspective distortion in a wider range. This camera can be used in any scene with an installation height, such as a station, a square, a wharf, a ship, etc., where a deep depth of field is required and there is no requirement for perspective distortion.

[0035] The "deflection" of the angle in the imaging system of the present invention is the rotation angle of the imaging lens and the image collection unit (sensor) with respect to their mounting main axes. The present invention sets the image collection unit and the imaging lens so as to have a second angle α and a third angle β that are inclined in the direction opposite to the inclination direction of the camera lens barrel with respect to the main axis of the camera lens barrel in the reference direction, and makes the second angle α and the third angle β different from each other, so that the two form an angle, and the intersection line of the two is below and intersects the plane passing through the object-side focal point, and substantially satisfies the principle of shine-proof, whereby clear images can be formed in both the regions before and after the plane passing through the object-side focal point. The "translation" in the imaging system of the present invention is the translation of the center of the lens and the center of the sensor with respect to the mounting main axis of the camera lens barrel, and its main purpose is to realize the relative position offset between the center of the lens optical axis and the center of the sensor. In the use of the solution of the present invention, it can be adaptively adjusted according to different application scenarios, the mounting height of the video camera, the required field of view range required by regulations, etc.

[0036] In short, the present invention inclines the imaging angle downward from the horizontal line, cooperates with the reverse inclination of the image collection unit and the imaging lens, and adopts different inclination angles for the two, so that the object plane, the image collection unit and the imaging lens satisfy the principle of shine-proof. By the translation of the imaging lens and the rotation of the imaging lens and the image collection unit, not only can the depth of field be widened and the clear field of view range be expanded, but also perspective distortion can be avoided.

[0037] In addition, when the present invention is used as an in-vehicle imaging system, it is possible to make the image of a distant position behind the vehicle, which is more important for the driver, clearer, and thus it is possible to provide better driving safety protection.

Brief Description of the Drawings

[0038]

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Embodiments for Carrying Out the Invention

[0039] Hereinafter, the present invention will be described in more detail with reference to embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0040] FIG. 4 is a real - life picture of a shooting scene in each embodiment and comparative example of the present invention. The images in each embodiment and comparative example of the present invention are all taken in this scene, and these examples will be described by taking the in - vehicle scene as an example. Note that in the following embodiments and comparative examples, the in - vehicle imaging is taken as an example to explain the solutions, but the solutions of the present invention are not limited to the application to in - vehicle imaging systems, and can also be applied to various scenes that require inclined shooting, such as stations, squares, shopping malls, highways, etc.

[0041] FIG. 5 is a schematic diagram showing the transition of the inclination settings of each part of the camera in the imaging system of this embodiment. First, FIGS. 5A and 5B show the setting method of an ordinary camera, and FIGS. 5C - 5E show the setting method of Embodiment 1 of the present invention. In each figure, the left - hand part is the imaging lens (or front - focus structure) 100, and the right - hand part is the image collection unit (or rear - focus structure) 200. Both are installed in the camera body 300 (including the lens barrel 301 and the collection chamber 302). The imaging lens 100 is installed in the camera lens barrel at the front end of the camera body 300, and the image collection unit 200 is installed at the rear end of the camera body 300.

[0042] Comparative Example 1 When the imaging device of FIG. 5A is attached to a vehicle, it directly photographs towards the rear of the vehicle, and the imaging lens 100 is set parallel to the image collection unit 200. When the imaging device of FIG. 5B is attached to a vehicle, it photographs while tilting downward towards the rear of the vehicle, and the imaging lens 100 is set parallel to the image collection unit 200.

[0043] The image taken by the shooting method of FIG. 5A is as shown in FIG. 8. In the figure, the left side is the overall view taken, the central part is the enlarged view of the front checkerboard calibration target within the overall view, and the right side is the enlarged view of the black sedan and the rear resolution calibration plate within the overall view respectively. As is clear from the figure, the shape of the figure on the resolution calibration plate is significantly distorted. The left side of the checkerboard is larger than the right side, and the grid in the figure is no longer a standard grid. Also, in this figure, half of the vehicle body is blocked, the horizon line is in the center of the image, the field of view in front of the vehicle is insufficient, and the field of view outside the vehicle body does not meet the regulatory requirements.

[0044] Comparative Example 2 According to the camera setting of FIG. 5B, the camera is tilted downward by about 10 degrees, and also tilted about 10 degrees outside the vehicle body to reduce the proportion of the vehicle body occupied in the image. The image taken is as shown in FIG. 9. In the figure, the left side is the overall view taken, the central part is the enlarged view of the front checkerboard calibration target within the overall view, and the right side is the enlarged view of the black sedan and the rear resolution calibration plate within the overall image respectively. Since all the following shooting figures are set in this way, they will not be repeated later. As can be seen from the figure, when the camera is tilted both downward and outside the vehicle body, more serious perspective distortion occurs, and obvious tilts occur in the lines on both the front resolution calibration plate and the rear checkerboard calibration target, and the grid has serious distortion.

[0045] Example C to E in FIG. 5 are the shooting setting methods of the embodiments of the present invention. Here, C is a side view schematic diagram, and D and E are top view schematic diagrams (no change in the member size seen from other directions due to rotation or deflection is depicted in each figure, and the figures are only used to show two-directional deflection and translation). In this embodiment, as shown in FIG. 6, when the imaging device is attached to the vehicle, it shoots while tilting downward toward the rear of the vehicle. That is, the main axis of the camera body is tilted downward at a first angle θ with respect to the horizontal direction. Here, the vertically downward direction is called the first direction. 10 in FIG. 6 represents the horizontal line as the "reference direction" of this embodiment. Both the imaging lens 100 and the image collection unit 200 are tilted in the opposite direction with respect to the main axis of the camera lens barrel (the central axis of the lens barrel), that is, they form an angle with the main axis in the clockwise direction with respect to the main axis of the camera. The tilting directions of the imaging lens 100 and the image collection unit 200 (or the normal directions of both) with respect to the main axis of the camera lens barrel are opposite to the tilting direction of the main axis of the camera lens barrel with respect to the horizontal direction, and the tilting angles are the second angle α and the third angle β respectively. 10 represents the horizontal direction (the "reference direction" in this embodiment), and 20 and 30 represent the normals of the imaging lens 100 and the image collection unit 200 respectively. Preferably, the third angle β at which the image collection unit 200 tilts is larger than the second angle α at which the imaging lens 100 tilts, and the second angle α and the third angle β are different.

[0046] Preferably, the object-side focus of the imaging lens is located behind the side of the target vehicle. The plane passing through the object-side focus intersects with the intersection line of the planes where both the image collection unit and the imaging lens are located to form the object-side focal plane S. Moreover, the third angle β and the second angle α satisfy the relationship arctan(β - α) = f / (H - h), where H is the height of the center of the imaging lens from the ground, f is the focal length of the imaging lens, and h is the preset height of the object-side focal plane S from the ground. In this way, the camera can satisfy the principle of anti-glare during imaging, and further, clear images can be formed in the areas before and after the plane passing through the object-side focus.

[0047] Preferably, as shown in the plan views of D and E in FIG. 5, the imaging lens 100 is offset (translated) with respect to the main axis of the camera barrel, and the offset distance is d. This offset distance is the value obtained by multiplying the distance L between the imaging lens 100 and the image acquisition unit 200 by tan8° to tan15°, that is, with respect to the center of the image acquisition unit, it is approximately equal to the distance corresponding to an offset of about 8 to 15 degrees of the center of the imaging lens with respect to the camera main axis. The offset direction is the direction away from the vehicle body (such an offset can also be realized by the image acquisition unit 200 translating toward the vehicle body direction with respect to the main axis of the camera barrel). At the same time, both the imaging lens 100 and the image acquisition unit 200 rotate with respect to their vertical center lines, and the rotation direction is the direction away from the vehicle body (those skilled in the art should understand that in other scenarios, the vehicle body can be replaced with the side wall of a building, the roadside of a highway, etc.). More specifically, as shown in FIG. 7, since the camera is shooting toward the rear of the vehicle body, both the imaging lens 100 and the image acquisition unit 200 rotate by a certain angle γ toward the outside of the vehicle tail around their respective numerical direction center axes. Preferably, this angle is between 8 and 16 degrees. More preferably, this angle γ has a positive correlation with the distance by which the imaging lens 100 is offset with respect to the main axis of the camera barrel. Preferably, the rotation angles of the imaging lens 100 and the image acquisition unit 200 are the same as each other, but a slight difference in their rotation angles is not excluded.

[0048] As can be seen from FIG. 10, when the setting method in the embodiment of the present invention is adopted, (1) the vehicle body size in the captured image meets the design requirements, and the proportion occupied by the vehicle body is relatively small; (2) the horizon line is located in the central and upper parts of the screen, meets the design requirements, and is helpful for the driver's observation. Therefore, the driver can clearly see the situation of the road behind and the vehicle related to the current vehicle, and the forward view of the vehicle meets the design requirements; (3) the view outside the vehicle body becomes richer. More importantly, (4) in the image formed by the checkerboard calibration target, the perspective distortion of the checkerboard is effectively corrected, and (5) the image within the depth of field range of 4 to 30 meters required by Chinese road traffic regulations is enhanced.

[0049] Without adding any hardware costs, the present invention can greatly improve the image quality of the subject within the depth of field range of 4 to 30 meters only by setting and adjusting the relative positional relationship and shooting direction among the focal plane of the imaging lens, the CMOS sensor, and the subject plane (by changing the main axis direction of the camera barrel). Therefore, the problem of perspective distortion of the subject can be effectively solved, and the imaging sharpness of the object near the horizon line can be effectively improved. As a result, the auxiliary effect of the rearview camera device on the driver can be further improved, thereby having significant economic and social benefits and broad market prospects.

[0050] In another implementation, the imaging system of the present invention is applied to photographing on a road outside a building, and the imaging device is attached to one or more corners of the building. Here, only one of them will be taken as an example. The imaging device has a certain mounting height and photographs towards a road substantially parallel to the building outside the outer wall of the building. The camera lens barrel of the imaging device is inclined downward and is inclined downward at a first angle with respect to the horizontal direction. Both the imaging lens and the image collection unit are inclined in the opposite direction with respect to the main axis of the camera lens barrel, and the inclination direction of the imaging lens and the image collection unit with respect to the main axis of the camera lens barrel and the inclination direction of the main axis of the camera lens barrel with respect to the horizontal direction are opposite, and the inclination angles are the second angle and the third angle respectively.

[0051] At the same time, the imaging lens is offset (translated) with respect to the main axis of the camera lens barrel, and the offset direction is the direction away from the wall of the building. This offset distance is approximately equal to the value obtained by multiplying the distance L between the imaging lens and the image collection unit by tan8° to tan15°. At the same time, both the imaging lens and the image collection unit rotate with respect to their respective substantially vertical centerlines, and the rotation direction is the direction away from the wall of the building.

[0052] As above, the principle of the present invention has been described in detail in conjunction with the preferred embodiments of the present invention. However, those skilled in the art should understand that the above embodiments are only explanations of the general implementation method of the present invention and do not limit the scope of the present invention. The details in the embodiments do not limit the scope of the present invention. Any obvious changes such as equivalent conversions and simple substitutions based on the technical solution of the present invention without departing from the spirit and scope of the present invention should be included within the protection scope of the present invention.

Claims

1. Comprising a camera body, an image collection unit, and an imaging lens, The front end of the camera body is a camera barrel, The imaging lens is mounted within the camera barrel, The image collection unit is mounted at the rear end of the camera body, and The camera barrel has a first angle θ that inclines in a first direction with respect to a reference direction, The imaging lens and the image collection unit respectively have a second angle α and a third angle β that incline in a direction opposite to the inclination direction of the camera barrel with respect to the principal axis of the camera barrel, characterized in that it is an imaging system for non-normal direction shooting.

2. The imaging system according to claim 1, characterized in that the second angle α and the third angle β are different from each other.

3. The imaging system according to claim 2, characterized in that the third angle β is greater than the second angle α such that the plane in which the image collection unit and the imaging lens are located intersects on one side of the direction in which the camera barrel inclines and forms an acute angle.

4. The imaging lens has a horizontal translation or offset in a second direction with respect to the principal axis of the camera barrel, or the image collection unit has a horizontal translation or offset in a direction opposite to the second direction with respect to the principal axis of the camera barrel. The second direction is perpendicular to the first direction and the principal axis of the camera barrel and faces the subject. The image collection unit and the imaging lens have a deflection angle γ in the second direction, characterized in that it is the imaging system according to claim 2.

5. The imaging system according to claim 3, characterized in that the first angle θ is 6 to 14 degrees, the second angle α is 6 to 14 degrees, and the third angle β is 8 to 17 degrees.

6. The imaging system is an in-vehicle imaging system for attachment to a target vehicle. The imaging system is attached to the side portion of the target vehicle. The first direction is a vertically downward direction, and the second direction is a direction away from the vehicle body, characterized in that it is the imaging system according to any one of claims 1 to 3.

7. The imaging system according to claim 1, characterized in that it includes a plurality of imaging structures composed of an image collection unit, an imaging lens, and a camera body, which are respectively attached to both sides of the vehicle.

8. The imaging system according to claim 1, characterized in that it is mounted at a position higher than the target imaging area.

9. The object-side focus of the imaging lens is located behind the side of the target vehicle, and the plane passing through the object-side focus intersects the intersection line of the plane in which both the image collection unit and the imaging lens are located, forming an object-side focal plane S. Here, the third angle β and the second angle α satisfy the relationship arctan(β - α) = f / (H - h), where H is the height of the center of the imaging lens from the ground, f is the focal length of the imaging lens, and h is the preset height of the object-side focal plane S from the ground. The imaging system according to claim 1, characterized in that.

10. A method for setting the structure of an imaging system including a camera body, an image collection unit, and an imaging lens, Attaching the image collection unit and the imaging lens to the front end and the rear end of the camera body respectively; Attaching the imaging system such that the camera body is inclined at a first angle θ with respect to the reference direction; Setting the image collection unit and the imaging lens to have different second angles α and third angles β that are inclined in directions opposite to the inclination direction of the camera body with respect to the main axis of the camera body, respectively. A method for setting the structure of an imaging system, characterized by including.

11. The method for setting the structure of the imaging system according to claim 9, characterized in that the third angle β is larger than the second angle α such that the plane in which the image collection unit and the imaging lens are located intersects to form an acute angle.

12. The image collection unit has a horizontal offset in a second direction with respect to the main axis of the camera body, the second direction is perpendicular to the first direction and the main axis of the camera body, and the image collection unit and the imaging lens have a deflection angle in a third direction, the third direction being opposite to the second direction. The method for setting the structure of the imaging system according to claim 9, characterized in that.

13. The first angle θ is 6 to 14 degrees, the second angle α is 6 to 14 degrees, and the third angle β is 8 to 17 degrees. A method for setting the structure of the imaging system according to claim 9, characterized in that.

Images