JP6584870B2 - In-vehicle image recognition apparatus and manufacturing method thereof - Google Patents

Description

  The present invention relates to an in-vehicle image recognition apparatus and a manufacturing method thereof.

2. Description of the Related Art In recent years, a technique for detecting a line (lane) indicating a travel route on a road using an in-vehicle camera has been used in a lane maintenance support system for improving the traveling safety of a vehicle.
For example, there is a recognition device capable of capturing a travel route (lane or lane) on a road with a camera provided in the vehicle and recognizing the travel route division line or the road structure based on the image processing result of the captured image. It has been proposed (see, for example, Patent Document 1).
There is also provided a lane recognition device that can detect the left and right lane positions of an own vehicle in an image captured by an in-vehicle camera (see, for example, Patent Document 2).
Each of these devices uses a vehicle-mounted camera with the focus adjusted.

JP-A-8-315125 JP 2007-264714 A

  However, even if the focus is adjusted, sufficient resolving power is not always obtained. Due to the lack of resolving power, an error may occur in the recognition of a line such as a white line indicating the boundary of the lane drawn on the road surface. In order to reduce the occurrence of errors, it was necessary to use an expensive lens such as an aspherical lens that has high resolving power.

  In view of the above circumstances, an object of the present invention is to provide an in-vehicle image recognition apparatus capable of improving the recognition accuracy of a line indicating a traveling lane without using an expensive lens, and a method for manufacturing the same.

The image formed by the lens differs in the sharpness of the image in the circumferential direction and the radial direction except for the center of the image. Further, by changing the focus position, an image with sharp edges extending in the circumferential direction can be obtained, or an image with sharp edges extending in the radial direction can be obtained. In a normal camera, a focus position that balances both the circumferential and radial sharpness is selected.
However, the inventors of the present invention have found that the focus position where the radial edge is sharp is more suitable for the in-vehicle image recognition apparatus. In-vehicle image recognition devices often have a function of recognizing a line representing a lane on a road surface. The sharp edge in the radial direction can improve the recognition accuracy at the time of lane recognition.
Originally, if an image having both sharp edges in the radial direction and edges in the circumferential direction is obtained, it is more preferable. However, such a lens is very expensive and is not practical for use in an in-vehicle image recognition apparatus that is desired to be widely mounted in a vehicle. If it is the structure of this invention, the vehicle-mounted image recognition apparatus can be provided at low cost.
In order to obtain an image with sharp edges in the radial direction, the focus position may be selected as such at the time of manufacturing the on-vehicle image recognition device, but even if a lens having such characteristics is selected. good. In any case, the effect of the present invention can be obtained if an image having sharp edges in the radial direction is obtained as a result.

  Hereinafter, it will be described more precisely. In order to solve the above-described problem, an in-vehicle image recognition apparatus according to an exemplary embodiment of the present invention includes a fixed-focus imaging optical system that forms an image of a front scene in the optical axis direction on the rear side. An image sensor that is arranged on the rear side in the optical axis direction and the optical axis of the imaging optical system passes through an imaging surface, and an integrated circuit that captures an image of the scene photographed by the image sensor and performs image recognition processing The position where the resolving power in the radial direction of the light passing through the imaging optical system converges when the projection surface is moved in the optical axis direction is called a radial focus, and the converged light The position at which the resolving power in the circumferential direction shows a maximum when moving the projection plane in the optical axis direction is called a circumferential focus, and the lower half of the scene in the vertical direction is projected below the part of the imaging plane. Half of the diagonal length of the imaging surface When the intersection between the optical axis and the imaging surface is called the optical axis center, which is called the image height, the distance from the optical axis center of the image projected by the imaging optical system onto the imaging element is 70% of the image height. In this position, at least the lower half of the imaging surface is located closer to the circumferential focus than an intermediate position between the radial focus and the circumferential focus, and the distance between the circumferential focus and the imaging surface is The image recognition processing performed by the integrated circuit is smaller than the distance between the circumferential focus and the radial focus, and includes processing for recognizing a line representing a travel lane drawn on the road surface.

  According to the present invention, in an in-vehicle image recognition apparatus, it is possible to improve the recognition accuracy of a line indicating a travel lane without using an expensive lens.

It is a schematic diagram which shows an example of a vehicle provided with the vehicle-mounted image recognition apparatus of 1st Embodiment. It is a schematic diagram which shows the example of attachment to the vehicle interior of the vehicle-mounted image recognition apparatus of 1st Embodiment. It is a figure which shows an example of a function structure of the vehicle-mounted image recognition apparatus of 1st Embodiment. It is a schematic diagram which shows an example of the image which a vehicle-mounted image recognition apparatus images with an imaging part. It is a schematic diagram which shows the structure of the imaging part of the vehicle-mounted image recognition apparatus of 1st Embodiment. It is a graph which shows an example of the MTF curve of the imaging optical system in the vehicle-mounted image recognition apparatus of 1st Embodiment. It is a disassembled perspective view of the imaging part of the vehicle-mounted image recognition apparatus which concerns on 1st Embodiment. It is a fragmentary sectional view of the image pick-up part with which the in-vehicle image recognition device concerning a 1st embodiment is provided. It is a flowchart of the manufacturing method of the vehicle-mounted image recognition apparatus which concerns on 1st Embodiment. It is a flowchart of the manufacturing method of the modification of 1st Embodiment. It is a graph which shows an example of the MTF curve of the imaging optical system in 2nd Embodiment. It is a fragmentary sectional view of the image pick-up part with which the in-vehicle image recognition device concerning a 3rd embodiment is provided. It is a fragmentary sectional view of the image pick-up part with which the in-vehicle image recognition device concerning a 4th embodiment is provided. It is a flowchart of the manufacturing method of the vehicle-mounted image recognition apparatus which concerns on 4th Embodiment.

Hereinafter, embodiments will be described with reference to the drawings.
In the drawings used in the following description, for the purpose of emphasizing the feature portion, the feature portion may be shown in an enlarged manner for convenience, and the dimensional ratios of the respective constituent elements are not always the same as in practice. Absent. In addition, for the same purpose, portions that are not characteristic may be omitted from illustration.
In the following description, an XYZ orthogonal coordinate system and an lxlylz orthogonal coordinate system are used as necessary. Here, the XYZ orthogonal coordinate system is an orthogonal coordinate system based on the traveling direction of the vehicle 2. The lxllyz orthogonal coordinate system is an orthogonal coordinate system based on the optical axis direction of the vehicle-mounted image recognition apparatus 1.

<First Embodiment>
A vehicle-mounted image recognition device 1 according to the first embodiment will be described. Drawing 1 is a mimetic diagram showing an example of vehicles 2 provided with in-vehicle image recognition device 1 of a 1st embodiment. The forward direction of the vehicle 2 is defined as a positive direction of the Z axis, and orthogonal directions on a plane perpendicular to the Z axis direction are defined as an X axis direction and a Y axis direction, respectively. Here, the X-axis direction is the horizontal left direction of the vehicle 2, and the Y-axis direction is the vertical upward direction of the vehicle 2.
The in-vehicle image recognition apparatus 1 captures an image of the front of the vehicle 2 and detects information related to the surroundings (obstacles, road surface, etc.) of the vehicle 2. For example, the in-vehicle image recognition apparatus 1 captures, for example, a scene in front of the vehicle as a lane keeping support system, and recognizes a line indicating a travel lane on the road. The line indicating the traveling lane on the road is a display object such as a white line drawn on the road.
The in-vehicle image recognition device 1 may be disposed in the passenger compartment of the vehicle 2 or may be disposed on the front grill of the vehicle 2. Here, the case where the vehicle-mounted image recognition device 1 is disposed in the vehicle interior of the vehicle 2 will be described as an example.
Note that the in-vehicle image recognition apparatus 1 may capture information behind the vehicle 2 and detect information about the surroundings of the vehicle 2 (obstacles, road surfaces, etc.).

  The in-vehicle image recognition apparatus 1 includes an imaging unit 10 and a control unit 20. The imaging unit 10 captures a scene in front of the vehicle 2. The control unit 20 performs image acquisition and image processing of the image captured by the imaging unit 10.

  FIG. 2 is a schematic diagram illustrating an example of mounting the vehicle-mounted image recognition device 1 according to the first embodiment in a vehicle interior. In this embodiment, the vehicle-mounted image recognition device 1 is attached to the vehicle with the field of view of the imaging unit 10 capturing the front of the vehicle. In this specification, the direction in which the field of view of the imaging unit 10 faces when viewed from the vehicle-mounted image recognition device 1 is described as being in front of the vehicle-mounted image recognition device 1. Note that the in-vehicle image recognition device 1 can be attached and used in a state where the side and rear of the vehicle are captured in the field of view of the imaging unit 10. In that case, the front of the vehicle-mounted image recognition device 1 faces the side or the rear of the vehicle. The front direction of the in-vehicle image recognition apparatus 1 is defined as a positive direction of the lz axis, and orthogonal directions on a plane perpendicular to the lz axis direction are defined as an lx axis direction and a ly axis direction, respectively. Here, the lx-axis direction is the horizontal left direction of the vehicle 2 and coincides with the X-axis direction. The configuration of the in-vehicle image recognition apparatus 1 shown here is an example, and for example, the room mirror RVM may share a part with the casing of the in-vehicle image recognition apparatus.

  FIG. 3 is a diagram illustrating an example of a functional configuration of the vehicle-mounted image recognition device 1 according to the first embodiment. The imaging unit 10 included in the in-vehicle image recognition apparatus 1 includes an imaging optical system 11 and an imaging element 12. The “imaging optical system” as used herein means an optical system that includes a lens disposed on the optical axis and projects a scene on one side of the optical axis.

The imaging optical system 11 is a fixed focus type imaging optical system that forms an image on one side in the direction of the optical axis AX1. The optical axis AX1 of the imaging optical system 11 extends in the front-rear direction of the in-vehicle image recognition apparatus 1. One side of the optical axis AX1 is located on the front side of the in-vehicle image recognition apparatus 1, and the other side of the optical axis AX1 is located on the rear side of the in-vehicle image recognition apparatus 1. In this specification, the front side in the optical axis AX1 direction may be expressed as the positive direction side of the lz axis. Similarly, the rear side in the direction of the optical axis AX1 may be expressed as the negative direction side of the lz axis.
The imaging device 12 is a solid-state imaging device such as a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor, and captures an image of a scene imaged on an imaging surface through the imaging optical system 11. .

The control unit 20 included in the in-vehicle image recognition apparatus 1 includes integrated circuits such as a CPU (Central Processing Unit), a memory, and an auxiliary storage device connected to each other via a bus. The control unit 20 functions as an image acquisition unit 21 and an image processing unit 22 when the CPU executes a program.
The image acquisition unit 21 acquires an image captured by the image sensor 12 from the image sensor 12. The image acquisition unit 21 outputs the acquired image to the image processing unit 22.
The image processing unit 22 performs image recognition processing on the image output from the image acquisition unit 21. The image processing unit 22 extracts and recognizes a line indicating a traveling lane on the road surface included in the input captured image.

FIG. 4 is a schematic diagram illustrating an example of an image IMG captured by the imaging unit 10 by the in-vehicle image recognition device 1. In FIG. 4, radial lines LR <b> 1 to LR <b> 8 and concentric circles CC <b> 1 to CC <b> 8 are drawn in order to describe the radial direction and the circumferential direction on the image, but such lines are included in the actual image. Absent. The concentric circles CC1 to CC8 are centered on the point Pv. Point Pv is the center of the image, and is the point where the optical axis AX1 of the imaging optical system 11 intersects with the imaging surface of the imaging element 12. As indicated by an arrow AR1 in FIG. 4, in the present invention, a direction along the radial lines LR1 to LR8 is referred to as a radial direction. Further, as indicated by the arrow AR2, the tangential direction of the concentric circles CC1 to CC8 is referred to as a circumferential direction. Note that the concentric circles CC1 to CC8 and the radial lines LR1 to LR8 in FIG. 4 are examples of these lines. The concentric circles in FIG. The directions are also circumferential directions and radial directions.
In the specific example of the image shown in FIG. 4, the center white line CL, the right line WLr, and the left line WLl are lines (that is, lanes) indicating a driving lane drawn on the road surface RD of the road. . These lanes extend in the radial direction from the vicinity of the center point Pv of the screen. As shown in FIG. 4, in the sight image in front of the vehicle, the line indicating the road lane is located on the outer side.

FIG. 5 is a schematic diagram illustrating a configuration of the imaging unit 10 of the vehicle-mounted image recognition device 1 according to the first embodiment.
The light emitted from the point A on the subject surface is collected by the imaging optical system 11 at a point A ′ on the imaging surface C of the imaging element 12. Light emitted from other points on the surface of the subject is also condensed at other points on the imaging surface by the imaging optical system 11. In this way, the light emitted from the subject is imaged on the imaging surface. The imaging surface C of the imaging device 12 is located at a distance f from the imaging optical system 11.

  FIG. 6 is a graph showing an example of the MTF curve of the imaging optical system 11 in the in-vehicle image recognition device 1 of the first embodiment. Here, MTF is an abbreviation for Modulation Transfer Function. The vertical axis of the graph representing the MTF curve shown in FIG. 6 indicates the resolving power of the imaging optical system 11. The horizontal axis indicates the position of the projection plane in the optical axis direction. In this example, the position is displayed as a relative position from the reference position.

  In FIG. 6, the resolving power is an index representing the quality of the image. The larger the value, the more details of the image can be read. In general, an image of black lines drawn on a white background and arranged in parallel at equal intervals is represented by the contrast ratio of the white and black portions in the projected image when projected onto the projection surface using an optical system. The The contrast ratio is expressed with 1 (100%) as the maximum. In order to explain the resolving power by such a method, it is necessary to specify the interval between the black lines which is generally assumed. FIG. 6 shows the contrast ratio of the white background portion with respect to the black line image to be arranged at an interval of 42 lp / mm. In addition, the MTF curve of FIG. 6 was measured with the image of visible light using ImageMaster HR by Trioptics. Lp / mm means line pairs per mm.

  A curve 37 in the graph of FIG. 6 represents the circumferential resolution measured at a position separated by 70% of the image height from the point Pv which is the center of the image. Similarly, the curve 36 represents the radial resolving power measured at a position separated from the point Pv by 70% of the image height. As is apparent from the graph, the position of the imaging surface where the resolving power is highest differs between the circumferential direction and the radial direction. The curve 35 represents the MTF curve at the center of the image, that is, the point Pv in FIG. Since there is no distinction between the circumferential direction and the radial direction at the center of the image, there is only one curve representing the resolving power.

  In general, since the imaging optical system is accompanied by aberrations, the radial focus Pm and the circumferential focus Ps do not coincide with each other at a place other than the center of the image. In the conventional on-vehicle image recognition apparatus, the imaging surface of the imaging element is positioned near the middle between the circumferential focal point and the radial focal point of the optical system to balance the resolution in both the circumferential direction and the radial direction. On the other hand, in the on-vehicle image recognition apparatus according to the present embodiment, the imaging surface C is located closer to the radial focus. The image height is half of the length of the diagonal line of the imaging surface C of the image sensor 12. The circumferential focus is a position at which the resolving power in the circumferential direction of the image projected by the imaging optical system shows a maximum when moving the projection surface in the optical axis direction. The radial focus is a position where the resolving power in the radial direction of the image projected by the imaging optical system shows a maximum when moving the projection surface in the optical axis direction.

As is apparent from FIG. 4, the line WLr and the line WLl displaying the road surface lane extend in the radial direction in the image IMG. And in order to ensure the recognition accuracy of these lines which display a lane, it is preferable that the edge of a line is clear on the image IMG. The edge of the line extending in the radial direction becomes clearer as the circumferential resolution is higher. On the other hand, radial resolution has little effect on the clarity of the line edges.
Since the imaging surface C is located closer to the radial focus, the vehicle-mounted image recognition apparatus according to the present embodiment recognizes the line that displays the lane without replacing the imaging optical system with a higher imaging performance. Can be increased.

  In FIG. 6, when the imaging surface C is located at the circumferential focus represented by Ps, the resolution in the circumferential direction is the highest. However, it is not necessary to make it completely coincide. For example, a relatively good resolving power can be obtained even at a relative position represented by point P11 in FIG. The value of MTF is 0.55 in this case. This position is closer to the circumferential focus Ps than the middle between the circumferential focus Ps and the radial focus Pm. In addition, a relatively good resolving power can be obtained even at a relative position represented by point P12 in FIG. In this case, the MTF value is 0.55. In the case where the imaging surface C is located at any of the points P11 and P12 in FIG. 6, the circumferential resolution is greater than the radial resolution. In the case of the position of the relative position −0.036 mm represented by the point P12, the radial resolution is inferior to the previous point P11 because it is on the opposite side of the radial focus Pm with respect to the circumferential focus Ps. However, as long as the circumferential direction resolving power is regarded as important, the effect of the present invention can be obtained even with such an arrangement.

  When the position of the imaging surface C is located further to the left than the circumferential focus Ps in FIG. 6, the radial resolution is further reduced and the circumferential resolution is also reduced. However, the state where the circumferential resolution exceeds the radial resolution does not change. Therefore, the resolution of the entire lane is reduced, but the lane boundary is kept relatively clear. When mass-producing an in-vehicle image recognition apparatus, it is difficult to maintain the assembly accuracy completely, and therefore the image pickup surface C may be mixed at the position described here. However, even when such a situation occurs, the vehicle-mounted image recognition apparatus of the present invention originally has a configuration in which priority is given to the circumferential resolution, so that a significant decrease in the recognition accuracy of the line displaying the lane can be avoided. However, since it is not preferable to deviate excessively to the left side of FIG. 6, it is necessary to avoid that the imaging plane C is located on the left side of the circumferential focus beyond the distance Dsm between the circumferential focus and the radial focus. There is. More preferably, the distance Dsm is less than half of the distance Dsm.

  Note that the MTF curve in FIG. 6 is measured for images of black lines on a white background arranged at intervals of 42 lp / mm, but the interval of black lines used when measuring the MTF function in the present invention is 42 lp. It is not limited to / mm. Measurements may be made on lines that are wider than this. However, if a line with an interval that is too wide compared to the pixel interval of the image sensor is selected, only an MTF curve that does not match the resolution of the image on the image sensor can be obtained. On the other hand, selecting an interval that is too narrow is not preferable because it requires excessive quality for the imaging optical system.

  A color filter array having a unit of 3 pixels × 3 pixels is usually used for the image sensor, and a color image is created by this filter. An example of such a color filter array is a Bayer filter. While taking a moving average in an area of 3 pixels × 3 pixels, it is assigned to each pixel, and red, green, and blue values are determined. For this reason, even if a line arranged at twice the pixel interval is imaged by such an image sensor, the obtained image has almost no contrast. Therefore, when measuring the MTF curve for the purpose of obtaining the in-vehicle image recognition device of the present invention, images of black lines arranged at intervals larger than twice the pixel interval should be used. On the other hand, the image of black lines arranged at 9 times the pixel interval shows sufficient contrast. Therefore, the interval of black lines when measuring the MTF curve is selected with this interval as the upper limit. What is necessary is just to select the imaging optical system which shows a characteristic.

  The pixel interval d of the light receiving elements in the image sensor 12 used in the first embodiment is 4.2 μm. Therefore, the value of 1 / (9d) is 26.4 lp / mm. In FIG. 6, the measurement is performed at 42 lp / mm where the interval is narrower than this. However, it is smaller than 1 / (2d), that is, 119 lp / mm, which is a value corresponding to twice the pixel interval. And when the position of an imaging surface is the point P11 in FIG. 6, and the point P12, the MTF value of circumferential direction resolving power shows 0.55. If the MTF value at the same position is measured at 26.4 lp / mm, a value larger than 0.55 is obtained.

  In FIG. 6, only one MTF curve at a position where the image height is 70% is shown in the circumferential direction resolution and the radial direction resolution. In general, the MTF curve at a position away from the center of the image varies depending on the position in the circumferential direction, but FIG. 6 represents this by a pair of MTF curves. In the in-vehicle image recognition apparatus according to the present embodiment, the imaging surface C is located closer to the circumferential focus than the intermediate position between the circumferential focus and the radial focus. Of C, only the half C_low on the lower side in the vertical direction in the image than the point Pv which is the center of the image is sufficient. The resolving power in the circumferential direction is important in the process of recognizing a line representing a traveling lane drawn on the road surface, because the road surface appears only in the lower half of the image. Since the imaging optical system 11 in this embodiment forms an inverted image, the lower half C_low in the vertical direction in the image corresponds to the upper half in the vertical direction in real space as shown in FIG.

  In the in-vehicle image recognition apparatus according to the present invention, a structure that does not use a part of the effective light receiving element of the imaging element can be employed. For example, an image sensor that can output an image in which one frame is composed of 1280 pixels horizontally and 800 pixels vertically is employed, but only an image in the range of 1200 pixels horizontally and 720 pixels vertically is used. In such a case, the imaging surface C in the present invention indicates an area composed of the horizontal 1200 pixels and the vertical 720 pixels. In this case, the image height also corresponds to half the length of the diagonal line of the area of the image sensor used to capture the image.

Next, the structure of the imaging unit 10 of the vehicle-mounted image recognition device 1 according to the first embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is an exploded perspective view of the imaging unit 10 of the in-vehicle image recognition device 1 according to the first embodiment. FIG. 8 is a partial cross-sectional view of the imaging unit 10 included in the in-vehicle image recognition device 1 according to the first embodiment.
The imaging unit 10 includes an imaging optical system 11, an imaging element 12, an optical system holding member 41, an element holding member 42, three flexible members 43, and three head-attached screws 44. In FIG. 8, one of the three flexible members 43 and the three head-attached screws 44 is not shown.

  The imaging optical system 11 is a fixed-focus optical system that forms an image of the front side scene in the direction of the optical axis AX1 on the rear side. In the specific example shown in FIG. 7, the imaging optical system 11 is a lens barrel having a lens fixed inside. The imaging optical system 11 includes a plurality of lenses. The F value of the imaging optical system 11 is 2, but it may be less than this.

  The imaging element 12 is disposed on the rear side of the imaging optical system 11 in the direction of the optical axis AX1. The optical axis AX1 of the imaging optical system 11 passes through the imaging surface C of the imaging element 12. The imaging device 12 converts the subject image formed through the lens of the imaging optical system 11 into an electronic signal and images it.

As shown in FIGS. 7 and 8, the optical system holding member 41 is a block having a rectangular shape when viewed along the optical axis AX1. The optical system holding member 41 is made of an aluminum alloy, but the material is not limited to the aluminum alloy. Ferritic or austenitic stainless steel or copper alloy may be used as the material. The imaging optical system 11 is fitted into an opening formed near the center of the main body 411 of the optical system holding member 41 and fixed to the optical system holding member 41.
A screw hole 51 is cut in the surface of the main body 411 of the optical system holding member 41 that faces the imaging element 12 side (the negative direction side of the lz axis). The screw hole 51 is one specific example of a fastening portion that fastens the head-attached screw 44 to the optical system holding member 41.

The element holding member 42 holds the image sensor 12. The imaging surface C of the imaging element 12 fixed (held) to the element holding member 42 faces the positive direction of the lz axis.
The element holding member 42 includes a main body 421 that is a plate made of an aluminum alloy. The element holding member 42 includes a through hole 52 penetrating in the lz-axis direction in the main body 421. The shaft portion of the head-attached screw 44 is passed through the through hole 52. The element holding member 42 includes a flexible printed circuit board PF on which the image pickup element 12 is mounted. The image pickup element 12 is fixed to the element holding member 42 through the flexible print board PF.
In FIG. 7, the number of the flexible member 43, the head-attached screw 44, the screw hole 51, and the through hole 52 is illustrated as three as an example, but is not limited thereto. Moreover, in FIG. 8, the number of the flexible member 43, the screw 44 with a head, the screw hole 51, and the through-hole 52 is shown as an example, respectively, and one illustration is abbreviate | omitted, respectively.

Next, specific configurations of the flexible member 43 and the head-attached screw 44 will be described.
The head-attached screw 44 passes through the through hole 52 of the element holding member 42 and is screwed into the screw hole 51 of the optical system holding member 41.
The flexible member 43 is an elastic member such as a spring or rubber formed of a material such as aluminum or phosphor bronze. FIG. 7 shows a case where the flexible member 43 is a coil spring as an example. The flexible member 43 is disposed coaxially with the head-attached screw 44 between the optical system holding member 41 and the element holding member 42. The flexible member 43 comes into contact with the surface fc3 of the optical system holding member 41 and the surface fc1 of the element holding member 42 by screwing the head-attached screw 44 into the screw hole 51, respectively. The flexible member 43 applies a force in a direction in which the optical system holding member 41 and the element holding member 42 are separated from each other. The surface fc3 is a surface facing the negative direction of the lz axis, and the surface fc1 is a surface facing the positive direction of the lz axis.

Specifically, the flexible member 43 presses the surface fc1 of the element holding member 42 with the force F2. The head-attached screw 44 presses the surface fc2 of the element holding member 42 facing the negative direction of the lz axis with the force F1. The head-attached screw 44 is screwed into the screw hole 51 while the head is pressed against the surface fc2 of the element holding member 42 by the flexible member 43. The distance D between the lens in the imaging optical system 11 and the imaging surface C of the imaging element 12 is adjusted by adjusting the amount of screwing the tip of the head-attached screw 44 into the screw hole 51. That is, the flexible member 43 and the head-attached screw 44 fix the relative positions of the optical system holding member 41 and the element holding member 42.
The flexible member 43 may be plastically deformed when a force is applied. This is because a member that has undergone plastic deformation also has elastic deformation at the same time, and can produce an action similar to that of an elastic member.

[Manufacturing method of in-vehicle image recognition device]
Next, the manufacturing method of the vehicle-mounted image recognition device 1 according to the first embodiment will be described.
FIG. 9 is a flowchart of the manufacturing method of the vehicle-mounted image recognition device 1 according to the first embodiment.
As shown in FIG. 9, the on-vehicle image recognition apparatus 1 according to the first embodiment includes an optical axis alignment step (step S101), a focus measurement step (step S102), an imaging surface position adjustment step (step S103), and a fixing. It is manufactured through the process (step S104). Hereinafter, each step will be specifically described.

First, in the optical axis alignment step, the azimuth of the optical axis AX1 of the imaging optical system 11 fixed to the optical system holding member 41 is measured and adjusted to a desired azimuth (step S101). This desirable azimuth is a state in which the optical axis AX1 intersects the imaging plane C perpendicularly. By adjusting the amount of screwing the tip of the head-attached screw 44 into the screw hole 51 of the optical system holding member 41, the position of the image sensor 12 is moved relative to the imaging optical system 11. Adjust the direction.
In addition, said optical axis alignment process (step S101) may be abbreviate | omitted.

Next, in the focus measurement step, the focus of the imaging optical system 11 is measured (step S102). More specifically, the distance from the optical axis center in the image projected on the projection plane is the circumferential focus of the image at a position 70% of the image height, and the distance from the optical axis center in the image projected on the projection plane. A location at 70% of the image height is selected as the focus measurement position, and the radial focus at that position is measured. When the optical axis AX1 passes through the point Pv which is the center of the imaging surface C, these focal points are almost constant regardless of the circumferential position. When the optical axis AX1 passes through a position different from the point Pv that is the center of the imaging surface C, the focal point differs depending on the circumferential position. In this case, it is necessary to select at least two positions on the lower half side of the imaging surface C as the focus measurement positions, measure the focal points, and determine the position of the imaging surface C with reference to the measurement results.
In the following description, the “circumferential focal point of an image at which the distance from the optical axis center in the image projected onto the projection plane is 70% of the image height” is also referred to as “70% circumferential focal point of the image height”. The “radial focus at a position where the distance from the optical axis center in the image projected onto the projection plane is 70% of the image height” is also referred to as “70% radial focus at the image height”.

Next, in the imaging surface position adjustment step, the imaging surface C of the imaging element 12 is moved relative to the imaging optical system 11 to adjust the position of the imaging surface C (step S103). More specifically, the position of the image pickup device 12 is set relative to the imaging optical system 11 by adjusting the amount by which the tip of the head-attached screw 44 is screwed into the screw hole 51 of the optical system holding member 41. Move to.
Here, the position of the image pickup surface 12 of the image pickup element 12 in the optical axis AX1 direction is closer to the image height 70% circumferential focus than the intermediate position between the image height 70% circumferential focus and the image height 70% radial focus. Adjusted to In FIG. 6, this position is closer to Ps than an intermediate position between the image height 70% radial direction focal point Pm and the image height 70% circumferential direction focal point Ps. Further, the imaging surface C of the imaging device 12 may be positioned on the right side of the point Ps in FIG. However, the distance between the image height 70% circumferential focus Ps and the imaging surface C must be adjusted to a position smaller than the distance between the image height 70% circumferential focus Ps and the image height 70% radial focus Pm.
In the optical axis alignment step described above, it is more preferable to align the optical axis AX1 with the position where the optical axis AX1 intersects the imaging surface C at the point Pv that is the center of the imaging surface C. In order to enable such adjustment, an adjustment mechanism for moving the image sensor in a direction perpendicular to the optical axis direction needs to be added to the imaging unit 10.
In the focus measurement step, the focus measurement position is not limited to a place where the distance from the optical axis center is 70% of the image height. For example, it may be a place separated from the center of the optical axis by a half distance between the center of the optical axis and the edge of the imaging surface C or a distance larger than that. As a result, if the position of the imaging surface C at a position away from the optical axis center by 70% of the image height is within the range required by the present invention, a manufacturing method for producing such a product is claimed in this application. This is a manufacturing method related to the item. The focus measurement position may be 70% or more away from the image height, but it is not preferable to select a position exceeding 100%.

  Next, in the fixing step, the image sensor 12 is relatively fixed to the imaging optical system 11 (step S104). Specifically, the jig that has adjusted the head screw 44 is removed from the head screw 44. The relative positions of the optical system holding member 41 and the element holding member 42 are fixed by the repulsive force accompanying the elastic deformation of the flexible member 43 or the repulsive force resulting from the residual stress accompanying the plastic deformation.

<Modification>
Next, a modified example of the manufacturing method of the first embodiment will be described. FIG. 10 is a flowchart of a manufacturing method according to a modification of the first embodiment.
As shown in FIG. 10, in the manufacturing method of the modification of the first embodiment, after the focus measurement step (step S102), the determination is made based on the measured focus (step S301) as shown in FIG. It differs from the manufacturing method of the vehicle-mounted image recognition apparatus 1 which concerns on 1st Embodiment. In the manufacturing method of the modified example of the first embodiment, the description of the same procedure as the manufacturing method of the in-vehicle image recognition device 1 according to the first embodiment is omitted.

After the focus measurement step (step S102), the difference between the 70% circumferential focus and the 70% radial focus measured in step S102 is compared with a predetermined value (step S301). In the following description, “difference between 70% circumferential focus and 70% radial focus measured in step S102” is referred to as “difference between circumferential focus and radial focus” or simply “difference in focus”. Is also referred to.
In this example, in step S301, it is determined whether or not the focus difference is greater than or equal to a predetermined value. If the difference in focus is greater than or equal to the predetermined value (step S301—YES), the process proceeds to step S103. If the difference in focus is not greater than or equal to the predetermined value (step S301—NO), the process proceeds to step S104.

  As described above, in the manufacturing method according to the modified example of the first embodiment, the imaging surface position adjustment step is executed when the difference between the circumferential focus and the radial focus of the imaging optical system 11 is equal to or greater than a predetermined value. . Further, in the manufacturing method of this modification, the imaging surface position adjustment step is not executed when the difference between the circumferential focus and the radial focus of the imaging optical system 11 is less than a predetermined value.

As described above, in the manufacturing method according to the modification of the first embodiment, among the products to be manufactured, the imaging surface position is determined for a product in which the difference between the circumferential focus and the radial focus of the imaging optical system 11 is a predetermined value or more. The adjustment process is executed. Therefore, according to the manufacturing method of the modified example of the first embodiment, the imaging surface position adjustment step can be omitted for products whose focus difference is less than a predetermined value.
Further, in the manufacturing method according to the modified example of the first embodiment, the imaging surface position adjustment process is executed for products that belong to a range of a predetermined ratio counted from the one with the larger focus difference among the products to be manufactured. Good.

Second Embodiment
FIG. 11 is a graph illustrating an example of the MTF curve of the imaging optical system 11-2 according to the second embodiment of the present disclosure. The measurement conditions are the same as in FIG. The difference between the MTF curve of FIG. 11 and the MTF curve of FIG. 6 is that the circumferential resolution is higher than the radial resolution at the radial focal point Pm2. Such an imaging optical system showing an MTF curve is not usually treated as a high-quality imaging optical system in that the MTF curve is greatly different in the circumferential direction and the radial direction, and the focal position is also different. However, when applied to the in-vehicle image recognition apparatus according to the present disclosure, such an imaging optical system is effective because the outline of a line representing a traveling lane can be clearly displayed.

  When the imaging optical system 11-2 in the present embodiment is used, the circumferential resolution is higher than the radial resolution even if the imaging surface C is positioned on the radial focus. It is also possible to use the in-vehicle image recognition device in this state. However, as in the case of the first embodiment, it is more preferable that the imaging surface C is located in the vicinity of the focal point in the circumferential direction. This is because the circumferential resolution is further increased. A more preferable range of the position of the imaging surface C is the position closer to the circumferential focus Ps2 than the point P1 that is intermediate between the circumferential focus Ps2 and the radial focus Pm2, as in the case of the first embodiment. For example, a preferable position is the point P2. Another preferable position may be a point P3 which is a position on the opposite side of the radial focus Pm2 with respect to the circumferential focus Ps2.

  In the following description, when the imaging optical system 11 and the imaging optical system 11-2 are not distinguished from each other, the imaging optical system 11 and the imaging optical system 11-2 are collectively referred to simply as imaging. It is described as an optical system 11.

<Third Embodiment>
Next, a third embodiment will be described with reference to FIG.
FIG. 12 is a partial cross-sectional view of the imaging unit 10a included in the in-vehicle image recognition device according to the third embodiment.

  The in-vehicle image recognition device according to the third embodiment is the first in that the ends of the flexible member 43a are fixed to the optical system holding member 41a and the element holding member 42a, respectively, and are in an extended state. It is different from the vehicle-mounted image recognition device 1 according to the embodiment. Of the components of the imaging unit 10a shown in FIG. 12, the same components as those of the imaging unit 10 shown in FIG. 8 are denoted by the same reference numerals as those in FIG.

The optical system holding member 41a includes a screw hole 51a penetrating in the lz-axis direction. The element holding member 42a does not have a through hole, and is pushed upward by the tip of the head-attached screw 44a screwed from below the screw hole 51a.
In this example, the flexible member 43a is a coil spring. The flexible member 43a is disposed between the optical system holding member 41a and the element holding member 42a, and both ends thereof are fixed to the optical system holding member 41a and the element holding member 42a, respectively. The head-attached screw 44a applies a force in a direction to separate the optical system holding member 41a and the element holding member 42a to these members, whereas the flexible member 43a applies a force in a direction to bring these members closer. By adjusting the amount screwed into the screw hole 51a of the head-attached screw 44a, the distance D and direction between the lens inside the imaging optical system 11 and the imaging surface C of the imaging element 12 are adjusted. That is, the flexible member 43a and the head-attached screw 44a fix the relative positions of the optical system holding member 41a and the element holding member 42a.

  In FIG. 12, the number of the flexible member 43a, the head-attached screw 44a, and the screw hole 51a is two as an example, and one illustration is omitted.

<Fourth embodiment>
Next, a fourth embodiment will be described. The in-vehicle image recognition apparatus according to the fourth embodiment is for in-vehicle use according to the first embodiment in that the positional relationship between the imaging surface C of the imaging element 12 and the imaging optical system 11 is fixed by an adhesive instead of a screw. Different from the image recognition apparatus 1.
FIG. 13 is a partial cross-sectional view of the imaging unit 10b included in the in-vehicle image recognition device according to the fourth embodiment. Of the components of the imaging unit 10b shown in FIG. 13, the same components as those of the imaging unit 10 shown in FIG. 8 are denoted by the same reference numerals as those in FIG.

  The imaging unit 10b includes an optical system holding member 41b and an element holding member 42b. The optical system holding member 41 b and the element holding member 42 b are bonded by an adhesive 60.

  The element holding member 42b holds the imaging element 12. The element holding member 42b includes a main body portion 421b having a plate shape and a pair of arm portions 422b extending in the optical axis direction. The main body portion 421b extends across the optical axis AX1, and the arm portions 422b are connected to both ends thereof. The arm portion 422b has a groove 52b that opens toward the optical system holding member 41b at the tip.

  The adhesive 60 is applied in the groove 52b as shown in FIG. The width of the groove 52b in the lz-axis direction is wider than the width of the optical system holding member 41b in the lz-axis direction. Further, there is a gap between the edge 412b of the optical system holding member 41b and the bottom of the groove 52b. Therefore, the optical system holding member 41b can move in the lx, ly, and lz directions with the edge portion 412b accommodated in the groove 52b before the adhesive 60 is applied and before it is cured. , Ly, and lz axes.

  The adhesive 60 is, for example, an ultraviolet curable resin that is cured by irradiation with ultraviolet rays. The adhesive 60 is not cured after being applied to the grooves 52b and before being irradiated with ultraviolet rays. With the distance D and orientation relationship between the imaging optical system 11 and the imaging surface C of the imaging element 12 adjusted, the adhesive 60 applied to the groove 52b is irradiated with ultraviolet rays. The adhesive 60 is cured by the ultraviolet irradiation, and the relative positional relationship between the optical system holding member 41b and the element holding member 42b is fixed while the distance D and the orientation are adjusted.

Next, the manufacturing method of the vehicle-mounted image recognition device 1b according to the fourth embodiment will be described.
FIG. 14 is a flowchart of the manufacturing method of the vehicle-mounted image recognition device 1b according to the fourth embodiment.
The manufacturing method of the on-vehicle image recognition device 1b according to the fourth embodiment is different from the optical axis alignment step (step S101), the imaging surface position adjustment step (step S103), and the fixing step (step S104). In the point provided with an alignment process (step S101a), an imaging surface position adjustment process (step S103a), a filling process for filling the adhesive 60 (step S201), and a curing process for curing the adhesive 60 (step S202). It differs from the manufacturing method of the vehicle-mounted image recognition apparatus 1 which concerns on 1 embodiment. Therefore, about the manufacturing method of the vehicle-mounted image recognition apparatus 1b, the description is abbreviate | omitted about the component same as the manufacturing method of the vehicle-mounted image recognition apparatus 1b which concerns on 1st Embodiment.

First, the edge 412b of the optical system holding member 41b is inserted into the groove 52b of the element holding member 42b. At this time, the element holding member 42b and the optical system holding member 41b are each held by a jig not shown. These jigs can change the relative orientation and positional relationship between the element holding member 42b and the optical system holding member 41b. The edge 412b is not in contact with the inner surface of the groove 52b.
Next, in the optical axis alignment step, the azimuth of the optical axis AX1 of the imaging optical system 11 fixed to the optical system holding member 41b is measured and adjusted to a desired azimuth (step S101a). This desirable azimuth is a state in which the optical axis AX1 intersects the imaging surface C perpendicularly and passes through the center of the imaging surface C. Since the edge 412b of the optical system holding member 41b is not in contact with the inside of the groove 52b of the element holding member 42b, the optical system holding member 41b is moved from the element holding member 42b to lx, It can be moved in the ly and lz directions, and can be rotated around the lx, ly, and lz axes.

After the focus measurement step (step S102), the position of the image pickup surface C of the image pickup device 12 is adjusted in the image pickup surface position adjustment step (step S103a). More specifically, the jig is operated to move the optical system holding member 41b in the direction of the optical axis AX1 with respect to the element holding member 42b.
In this manner, the position of the image pickup surface 12 of the image pickup element 12 in the direction of the optical axis AX1 is closer to the image height 70% circumferential focus than the intermediate position between the image height 70% circumferential focus and the image height 70% radial focus. It is adjusted to a close position.

  Next, in the filling step, the adhesive 60 is provided between the side surface of the optical system holding member 41b and the groove 52b of the element holding member 42b (step S201). More specifically, in a state where the side surface of the optical system holding member 41b and the groove 52b of the arm portion of the element holding member 42b face each other without contact (with a predetermined gap), the optical system holding member 41b At least part of the gap between the side surface and the groove 52 b is filled with the adhesive 60.

  The filling process of the adhesive 60 may be performed either before, after, or at the same time as the imaging surface position adjustment process (step S103a). When the adhesive 60 is provided before the imaging surface position adjustment step (step S103a), the adhesive 60 may be applied in advance to the side surface of the optical system holding member 41b or the groove 52b of the element holding member 42b.

  Next, in the curing process, the adhesive 60 is cured (step S202). For example, the adhesive 60 is cured by being irradiated with ultraviolet rays. As the adhesive 60 is cured, the relative position and orientation of the optical system holding member 41b and the element holding member 42b are fixed. Accordingly, the relative position and orientation between the image sensor 12 and the imaging optical system 11 are fixed.

  The adhesive 60 may be partially cured. In other words, the relative position and orientation between the image sensor 12 and the imaging optical system 11 may be fixed in two or more stages. For example, in the case where the curing of the adhesive 60 is performed in two or more stages, if the strength that does not break the state in which the orientation of the imaging optical system 11 is adjusted is obtained in the first curing, the imaging optical The relative orientation relationship between the system 11 and the image sensor 12 can be easily maintained thereafter.

  By doing in this way, it is possible to fix the relative positions and orientations of the imaging optical system 11 and the image pickup device 12 without losing the state after fine adjustment.

DESCRIPTION OF SYMBOLS 1 ... Vehicle-mounted image recognition apparatus, 2 ... Vehicle, 10 ... Imaging part, 11 ... Imaging optical system, 12 ... Imaging element, 20 ... Control part, 21 ... Image acquisition part, 22 ... Image processing part, 30 ... Main ray , 41, 41a, 41b ... optical system holding member, 42, 42a42b ... element holding member, 43, 43a ... flexible member, 44, 44a ... screw with head, 50 ... flexible printed wiring board

Claims (16)

A fixed focus type imaging optical system that forms an image of the front side in the optical axis direction on the rear side; and
An imaging element disposed on the rear side in the optical axis direction and having an optical axis of the imaging optical system passing through an imaging surface;
An integrated circuit that captures an image of the scene photographed by the image sensor and performs image recognition processing,
The position where the resolving power in the radial direction of the light that passes through the imaging optical system is maximum when moving the projection plane in the optical axis direction is called a radial focal point, and in the circumferential direction of the converged light. The position where the resolving power shows a maximum when moving the projection surface in the optical axis direction is called a circumferential focus, and the part of the imaging surface where the lower half of the scene in the vertical direction is projected is called the lower half. When the half of the diagonal length of the imaging surface is called an image height and the intersection of the optical axis and the imaging surface is called an optical axis center,
At a position where the distance from the optical axis center of the image projected by the imaging optical system onto the image sensor is 70% of the image height, at least the lower half of the imaging surface has a radial focus and a circumferential focus. Located closer to the circumferential focus than the middle position,
The distance between the circumferential focus and the imaging surface is smaller than the distance between the circumferential focus and the radial focus.
The on-vehicle image recognition apparatus, wherein the image recognition processing performed in the integrated circuit includes processing for recognizing a line representing a traveling lane drawn on a road surface.   The distance between the imaging surface and the circumferential focal point when the distance from the optical axis center is 70% of the image height is less than half of the distance between the imaging surface and the radial focal point. A vehicle-mounted image recognition apparatus. At a position where the distance from the optical axis center on the imaging surface of the imaging element is 70% of the image height, the circumferential resolution of an image projected on the imaging surface through the imaging optical system is radial. Higher than resolving power,
The pixel interval of the image sensor is d (mm),
3. The circumferential resolving power is defined as an MTF value for a plurality of black straight line images arranged in the circumferential direction and extending in the radial direction at 1 / (9d) lp / mm intervals on the imaging surface. Vehicle-mounted image recognition device. The imaging device has a color filter array on the surface of the imaging surface,

The in-vehicle image recognition apparatus according to claim 3, wherein the circumferential resolution has a value of 50% or more.   The in-vehicle image recognition apparatus according to claim 1, wherein an F value of the imaging optical system is 2 or less.   The in-vehicle image recognition apparatus according to any one of claims 1 to 5, wherein the image sensor is capable of outputting an image having a size of 1280 pixels horizontally and 720 pixels vertically per frame. An optical system holding member for holding the imaging optical system;
An element holding member for holding the imaging element;
A flexible member interposed between the optical system holding member and the element holding member;
An adjustment member that contacts one or both of the element holding member and the flexible member on the contact surface and is fastened to the optical system holding member at a fastening portion;
At least a part of the flexible member has undergone elastic deformation or plastic deformation,
The repulsive force resulting from the elastic deformation or the repulsive force resulting from the residual stress accompanying the plastic deformation acts in a direction in which the element holding member is pushed toward the contact surface. The on-vehicle image recognition device according to claim 1. An optical system holding member for holding the imaging optical system;
An element holding member for holding the imaging element,
The surface of the element holding member and the surface of the optical system holding member are not in contact with each other through a gap,
The in-vehicle image recognition device according to any one of claims 1 to 6, wherein the cured adhesive fills at least a part of the gap between the element holding member and the optical system holding member. A method for manufacturing an in-vehicle image recognition device according to any one of claims 1 to 8,
A focus measurement step of measuring a circumferential focus and a radial focus at a focus measurement position;
The imaging element is moved relative to the imaging optical system, and is closer to the circumferential focus than an intermediate position between the circumferential focus and the radial focus, and the circumferential focus and the imaging. An imaging surface position adjustment step of positioning the imaging surface at a position where the distance from the surface is smaller than the distance between the circumferential focus and the radial focus;
A fixing step of relatively fixing the imaging device and the imaging optical system,
The method of manufacturing an in-vehicle image recognition apparatus, wherein the focus measurement position is located at a position separated from the optical axis center by a distance that is half or greater than the distance between the optical axis center and the edge of the imaging surface.   Among the imaging optical systems supplied as parts to the production line on which the in-vehicle image recognition device is manufactured, the difference between the circumferential focal point and the radial focal point is arranged from the larger one and belongs to a predetermined ratio range. The method for manufacturing an in-vehicle image recognition apparatus according to claim 9, wherein the imaging surface position adjustment step is executed for an imaging optical system.   Among the products manufactured on the manufacturing line, in the focus measurement step, when the imaging surface position adjustment is performed using an imaging optical system in which the difference between the circumferential focus and the radial focus exceeds a predetermined value The manufacturing method of the vehicle-mounted image recognition apparatus of Claim 9 which performs a process. A fixed focus type imaging optical system that forms an image of the front side in the optical axis direction on the rear side; and
An imaging element disposed on the rear side in the optical axis direction and having an optical axis of the imaging optical system passing through an imaging surface;
An integrated circuit that captures video information captured by the image sensor and performs image recognition processing,
The position where the resolving power in the radial direction of the light that passes through the imaging optical system is maximum when moving the projection plane in the optical axis direction is called a radial focal point, and in the circumferential direction of the converged light. The position where the resolving power shows a maximum when moving the projection surface in the optical axis direction is called a circumferential focus, and the part of the imaging surface where the lower half of the scene in the vertical direction is projected is called the lower half. When the half of the diagonal length of the imaging surface is called an image height and the intersection of the optical axis and the imaging surface is called an optical axis center,
In at least the lower half of the imaging surface at a position 70% of the image height from the optical axis center, the circumferential resolution of the image projected by the imaging optical system onto the imaging device is higher than the radial resolution. ,
The image recognition process performed by the integrated circuit is an in-vehicle image recognition apparatus including a process of recognizing a line representing a traveling lane drawn on a road surface. The imaging device has a color filter array on the surface of the imaging surface,
The pixel interval of the image sensor is d (mm),
When the circumferential resolution is defined as an MTF value for a plurality of black straight images aligned in the circumferential direction and extending in the radial direction at 1 / (9d) lp / mm intervals on the imaging surface, the circumferential resolution is 50%. The in-vehicle image recognition apparatus according to claim 12, having the above values. An optical system holding member for holding the imaging optical system;
An element holding member for holding the imaging element;
A flexible member interposed between the optical system holding member and the element holding member;
An adjustment member that contacts one or both of the element holding member and the flexible member on a contact surface and is fastened to the optical system holding member at a fastening portion;
At least a part of the flexible member has undergone elastic deformation or plastic deformation,
14. The vehicle-mounted device according to claim 12, wherein the repulsive force accompanying the elastic deformation or the repulsive force resulting from the residual stress accompanying the plastic deformation acts in a direction of pushing the element holding member toward the contact surface. Image recognition device. An optical system holding member for holding the imaging optical system;
An element holding member for holding the imaging element,
The surface of the element holding member and the surface of the optical system holding member are not in contact with each other through a gap,
The in-vehicle image recognition apparatus according to claim 12 or 13, wherein the cured adhesive fills at least a part of the gap between the element holding member and the optical system holding member. A method for manufacturing the in-vehicle image recognition device according to any one of claims 12 to 15,
A focus measurement step of measuring a circumferential focus and a radial focus at a focus measurement position;
The imaging element is moved relative to the imaging optical system, and the circumferential resolution at a position where the distance from the optical axis center of the imaging surface is 70% of the image height is higher than the radial resolution. Resolving power adjustment process;
A fixing step of relatively fixing the imaging device and the imaging optical system,
The method of manufacturing an in-vehicle image recognition apparatus, wherein the focus measurement position is located at a position separated from the optical axis center by a distance that is half or greater than the distance between the optical axis center and the edge of the imaging surface.

Images