LiDAR SYSTEM FOR VEHICLE

Abstract

To provide a LiDAR system for a vehicle which can make light distribution of laser beams to apply to a radiation range appropriate while simplifying the structure of a radiation-side optical system.SOLUTION: A lens 58 of a radiation device 12 of a LiDAR system 10 has a reflection surface 69n of a circular cone side surface in which an apex T68n is near the light source 33n side and the central axis (an auxiliary line C68n) is inclined to the optical axis (the auxiliary line C33n) of the light source 33n, and reflects the laser beam from the light source 33n in a radiation direction at the reflection surface 69n.SELECTED DRAWING: Figure 6A

Description

[Technical field]

[0001] The present invention relates to a LiDAR system for a vehicle. [Background technology]

[0002] 2. Description of the Related Art LiDAR systems are known that are mounted on vehicles and detect pedestrians, preceding vehicles, and oncoming vehicles in front of the vehicle.

[0003] The LiDAR system for vehicles in Patent Document 1 includes an optical aperture, an emitter array including emitter elements arranged and configured to output optical signals through respective partial regions of the optical aperture to illuminate respective portions of a field of view, and an optical element disposed in at least a portion (specific optical path) of the optical path of the optical signal. The optical element is configured, for example, of a diffuser, a diffractive optical element, a lens, or the like, to deflect a corresponding illumination range of the optical path corresponding to the second subset of the optical signals without substantially changing the second subset of the optical signals (a set of optical signals corresponding to the specific optical path). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 2022-532936 Summary of the Invention [Problem to be solved by the invention]

[0005] In a vehicle LiDAR system, it is preferable to vary the intensity of the light distribution pattern in the irradiation range generated in front of the vehicle by emitting laser light from an irradiation device depending on the elevation angle (angle in the up-down direction) and azimuth angle (angle in the vehicle width direction) in order to reduce the total amount of light consumed.

[0006] The LiDAR system of Patent Document 1 generates a light distribution pattern in which the intensity of laser light in the desired emission direction is increased compared to other directions, but the structure is complex because the optical signal is divided into subsets, an individual diffuser or the like is provided in the optical path of each subset, and the desired light distribution pattern is generated by adjusting the overlap of the illuminated portions of each subset over the entire illumination range.

[0007] An object of the present invention is to provide a LiDAR system for a vehicle that can simplify the structure of the irradiating optical system while optimizing the light distribution of the laser light irradiated to the irradiation range. [Means for solving the problem]

[0008] The LiDAR system for a vehicle of the present invention comprises: An irradiation device that emits laser light toward a predetermined irradiation range; a light receiving device having a predetermined light receiving range including a range overlapping with the irradiation range as a search range, the light receiving device receiving the reflected light of the laser light from an object in the search range; A vehicle LiDAR system comprising: The irradiation device includes: A light source that emits the laser light; an optical unit having at least a part of a circumferential direction of a cone side surface, the apex of which is on the light source side and the central axis passing through the apex is biased with respect to the optical axis of the light source, as a reflecting surface, the optical unit reflecting the laser light from the light source incident from the apex side in a radial direction at the reflecting surface; Equipped with.

[0009] Another LiDAR system for a vehicle of the present invention includes: An irradiation device that emits laser light toward a predetermined irradiation range; a light receiving device having a predetermined light receiving range including a range overlapping with the irradiation range as a search range, the light receiving device receiving the reflected light of the laser light from an object in the search range; A vehicle LiDAR system comprising: The irradiation device includes: A plurality of light sources each having a parallel optical axis and emitting the laser light; a plurality of optical units provided corresponding to the respective light sources, each having at least a part of a circumferential direction of a cone side whose apex is on the corresponding light source side as a reflection surface, and reflecting the laser light from the corresponding light source incident from the apex side in a radiation direction at the reflection surface; Equipped with At least one of the plurality of optical units is a first optical unit, the central axis of which is offset with respect to an optical axis of the corresponding light source; At least one other of the plurality of optical sections is a second optical section, the central axis of which coincides with the optical axis of the corresponding light source. Effect of the Invention

[0010] According to the present invention, the optical unit of the irradiation device has at least a part of the circumferential direction of a cone side surface, the apex of which is on the light source side and the central axis passing through the apex is biased with respect to the optical axis of the light source, as a reflecting surface, and reflects the laser light from the light source incident from the apex side in the radial direction on the reflecting surface. As a result, it is not necessary to divide the optical path of the laser light from the light source and assign fine optical elements such as a diffuser to each division, so that the structure can be simplified and a desired light distribution pattern can be obtained. [Brief description of the drawings]

[0011] [Figure 1] FIG. 2 is a diagram showing the illumination range and light receiving range generated in front of a vehicle equipped with a LiDAR system at the right end of the front of the vehicle, as viewed from the side of the vehicle. [Diagram 2] FIG. 2 is a diagram showing the illumination range and light receiving range generated in front of a vehicle equipped with a LiDAR system at the right end of the front of the vehicle in a plan view of the vehicle. [Diagram 3] FIG. 1 is a block diagram of a LiDAR system. [Figure 4] 1A and 1B are diagrams illustrating a light distribution pattern generated in an illumination range by an illumination device. [Figure 5A] 4 is a perspective view of the front of the irradiation device of FIG. 3 as viewed diagonally from above right. [Figure 5B]4 is a perspective view of the front of the irradiation device of FIG. 3, seen diagonally from above on the left. [Figure 6A] FIG. 2 is a detailed perspective view of the illumination device including its internal structure. [Figure 6B] 6B is a view taken along the arrow F6B in FIG. 6A. [Figure 6C] FIG. 6B is a view taken along the arrow F6C in FIG. 6A. [Figure 7A] FIG. 2 is a diagram showing an optical path of a laser beam in an irradiation device. [Figure 7B] 7B is a view taken along the arrow F7A in FIG. 7A. [Figure 7C] 7B is a view taken along the arrow F7B in FIG. 7A. [Figure 7D] 7B is a view taken along the arrow F7C in FIG. 7A. [Figure 8] FIG. 2 is a plan view showing the illumination ranges generated individually by lens portions of a lens. [Figure 9A] 1 is a diagram showing a right-side illumination range that is set around the vehicle including the front thereof by emitting laser light from an illumination device mounted on the right front part of the vehicle while the vehicle is traveling on a road. FIG. [Figure 9B] 1 is a diagram showing an illumination range set in front of a vehicle by emitting laser light from illumination devices mounted on the right and left front parts of the vehicle while the vehicle is traveling on a road. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described. The present invention includes configurations obtained by modifying the embodiment in various ways within the scope of design matters of those skilled in the art. Note that the same reference numerals are used throughout the drawings to refer to components common to multiple embodiments.

[0013] (Irradiation range, light receiving range and search range) 1 and 2 are diagrams respectively showing an illumination range 13 and a light receiving range 15 generated in front of a vehicle 20 equipped with a LiDAR system 10 at the right end of the front, as viewed from the side and in a plan view of the vehicle 20. Typically, the vehicle 20 is equipped with the LiDAR system 10 at both the left end and the right end of the front. This vehicle 20 is assumed to be a right-hand drive vehicle. There are flash-type and scan-type LiDAR systems, and this LiDAR system 10 employs the flash-type.

[0014] The longitudinal centerline 24 is located at the center of the vehicle 20 in the vehicle width direction and is set at the eye height of the driver in the driver's seat in the vehicle height direction. The longitudinal centerline 24 extends parallel to the road surface 26, i.e., horizontally, in the longitudinal direction of the vehicle 20.

[0015] The LiDAR system 10 includes an illumination device 12 and a light receiving device 14. The illumination device 12 is housed together with the headlight 23's original light source (a light source that illuminates a road surface 26 with white visible light) in the housing of a right headlight 23 mounted on the front of a vehicle body 22. The light receiving device 14 is attached to the vehicle body 22 at a location slightly below the headlight 23 in the vertical direction (up and down direction) outside the headlight 23.

[0016] The irradiation device 12 emits a laser beam toward the irradiation range 13. The light receiving device 14 receives reflected light 46 (FIG. 3) that is returned when irradiation light 45 (FIG. 3) of the laser beam emitted from the irradiation device 12 hits a target 28 (FIG. 3). The light receiving device 14 can detect only reflected light 46 from the irradiation light 45 from the irradiation device 12. Therefore, the targets 28 that the LiDAR system 10 can detect are limited to targets 28 that exist in the search range 17 where the irradiation range 13 and the light receiving range 15 overlap.

[0017] 1 and 2, the illumination side central optical axis 40 extends along the center line (also the common bisector of the vertical and horizontal angles) of the field of view of the FOI (Field Of Illumination) when the illumination range 13 is viewed from the viewpoint of the illumination device 12. The illumination side main optical axis 41 is the path of the maximum intensity laser light emitted from the viewpoint of the FOI. The light receiving side central optical axis 42 extends along the center line (also the common bisector of the vertical and horizontal angles) of the field of view of the FOV (Field Of View) when the light receiving range 1 is viewed from the viewpoint of the light receiving device 14.

[0018] In FIG. 1, the horizontal plane 25 is illustrated to show the inclination angles of the irradiating side central optical axis 40 and the receiving side central optical axis 42. This horizontal plane 25 is parallel to both the longitudinal center line 24 and the road surface 26. γa1 (>0) is the downward inclination angle of the irradiating side central optical axis 40 with respect to the horizontal plane 25. γa2 (>0) is the downward inclination angle of the receiving side central optical axis 42 with respect to the horizontal plane 25. γa3 (>0) is the upward inclination angle of the irradiating side main optical axis 41 with respect to the irradiating side central optical axis 40 in the side view. There is a relationship of γa1<γa2. That is, in the side view of the vehicle 20, the irradiating side central optical axis 40 is more upward than the receiving side central optical axis 42.

[0019] γa3-γa1>0. That is, the irradiation-side main optical axis 41 is oriented upward with respect to the horizontal plane 25 when viewed forward from the vehicle 20. Although the irradiation device 12 is disposed vertically below the center line 24 in the front-rear direction of the vehicle 20, the irradiation-side main optical axis 41 gradually rises as it moves forward from the vehicle 20, and approaches the center line 24 in the front-rear direction.

[0020] αv1 is the vertical angle of view (longitudinal angle of view) of the FOI with the illumination device 12 as the viewpoint. αv2 is the vertical angle of view (longitudinal angle of view) of the FOV with the light receiving device 14 as the viewpoint. There is a relationship of αv1>αv2. Therefore, even if γa1<γa2 (FIG. 1), and even if the illumination side central optical axis 40 is more upward than the reception side central optical axis 42 in the side view of the vehicle 20, the downward inclination angle of the lower boundary line of the illumination range 13 in the side view of the vehicle 20 is larger than the downward inclination angle of the lower boundary line of the reception range 15.

[0021] L0 is a vertical auxiliary line drawn at the starting point of the laser light emitted from the irradiation device 12 to the irradiation range 13. L1 is a vertical auxiliary line drawn at the point where the light receiving range 15 reaches the road surface 26 in front of the vehicle 20. The irradiation range 13 includes at least the vertical auxiliary line L1 and reaches the road surface 26 before the vertical auxiliary line L1, that is, on the vehicle 20 side. The vertical auxiliary line L1 is also a point on the search range 17 on the road surface 26 that is the shortest distance to the vehicle 20 in the front-rear direction of the vehicle 20. Preferably, the irradiation range 13 also reaches the road surface 26 at the vertical auxiliary line L1, like the light receiving range 15. This is because the proportion of the search range 17 in the irradiation range 13 increases, and the total amount of light consumed by the irradiation range 13 can be reduced.

[0022] 2, the light receiving device 14 is hidden under the irradiation device 12, but the light receiving device 14 is located at approximately the same position as the irradiation device 12 in the vehicle width direction. This is because the search range 17 can be made wider by having the light receiving device 14 and the irradiation device 12 at the same position.

[0023] αh1 is the horizontal angle of view (horizontal angle of view) of the FOI. αh2 is the horizontal angle of view (horizontal angle of view) of the FOV. Although αh1 ≒ αh2, there is a relationship of αh1 > αh2. This is because the light receiving device 14 is more expensive than the irradiation device 12, and it is more cost-effective to increase the FOI and expand the search range 17 than to increase the FOV.

[0024] γb1 (>0) is the inclination angle of the irradiation-side main optical axis 41 toward the front-rear center line 24 with respect to the irradiation-side central optical axis 40 in a plan view. The irradiation-side central optical axis 40 faces outward in the vehicle width direction as seen from the vehicle 20, whereas the irradiation-side main optical axis 41 faces inward so as to approach the front-rear center line 24. Since the intensity of the laser light emitted from the irradiation device 12 to the irradiation range 13 differs depending on the direction in a plan view, the far boundary line of the irradiation range 13 is at its farthest distance in the direction of the irradiation-side main optical axis 41.

[0025] (LiDAR system) 3 is a block diagram of the LiDAR system 10. The LiDAR system 10 is controlled by a control device 30 outside the LiDAR system 10. The control device 30 is mounted on the vehicle 20 separately from the LiDAR system 10. The control device 30 is an integrated control device that can control not only the LiDAR system 10 but also other electronic devices (not shown) mounted on the vehicle 20 (e.g., ADB (Adaptive Driving Beam), AFS (Adaptive Front-Lighting System), or air conditioning temperature control).

[0026] The irradiation device 12 includes a light source device 32 and an irradiation-side optical system 36. The light source device 32 further includes at least one light source 33 (two in the illustrated example). Since the LiDAR system 10 is a flash-type LiDAR system, the control device 30 causes the multiple light sources 33 to emit light simultaneously at a predetermined cycle. Each light source 33 emits laser light toward the irradiation-side optical system 36. The optical axes 34 of the multiple light sources 33 are parallel to each other.

[0027] The irradiation side optical system 36 includes an optical device and a mounting element for the optical device. The irradiation side optical system 36 emits the incident light of the laser light from the light source device 32 to the irradiation range 13 with a predetermined intensity distribution (also a predetermined light distribution pattern). The more intense the laser light, the more it can reach the distant target 28 as irradiation light 45 and return reflected light 46 with an intensity equal to or greater than a predetermined value from the target 28 to the LiDAR system 10.

[0028] The light receiving device 14 includes a light receiving optical system 50 and a sensor 52. The sensor 52 has a plurality of sensor elements arranged in a lattice pattern. The light receiving optical system 50 causes the reflected light 46 received from the search range 17 to be incident on a sensor element of the sensor 52 that corresponds to the incident direction of the reflected light 46. The control device 30 can detect the incident direction of each reflected light 46 based on which sensor element of the sensor 52 the reflected light 46 is incident on.

[0029] The control device 30 also measures the distance to the target 28 according to the TOF (Time of Flight) based on the difference between the time when the flash of the light source 33 is turned on and the time when the reflected light 46 is received by each sensor element of the sensor 52 in the light receiving device 14. In this way, the control device 30 detects the position of each target 28 based on the incident direction of the reflected light 46 and the measured distance to the target 28 from which each reflected light 46 is reflected.

[0030] Furthermore, the intensity of the reflected light 46 is related not only to the distance from the LiDAR system 10 to the target 28 but also to the reflectance of the target 28. The reflectance of the target 28 is related to the type of the target 28. For example, one type of target 28 is a dividing line (e.g., a white line) that divides the driving lane of the vehicle 20 on the road surface 26, and the location of the dividing line on the road surface 26 can be searched for from the reflectance.

[0031] (Light distribution pattern) Fig. 4 is a diagram showing a light distribution pattern generated in the irradiation range 13 by the irradiation device 12. The light distribution pattern in Fig. 4 is assumed to be generated by the LiDAR system 10 installed at the right end of the front of the vehicle 20 as shown in Fig. 2. This light distribution pattern also shows one generated on a virtual screen erected at a predetermined distance in front of the vehicle 20 facing the vehicle 20.

[0032] Figure 4 shows a color light distribution pattern converted to a monochrome grayscale display. In the color light distribution pattern, the color changes from red (warm color) to blue (cool color) as the intensity of the laser light goes from high to low. For this reason, in the grayscale of Figure 4, the red of maximum intensity is displayed as black, as is the ultramarine of minimum intensity, and the intermediate yellow is displayed as whitish. In other words, the shades do not necessarily correspond to the illuminance.

[0033] 4, the horizontal axis is the azimuth angle, and the vertical axis is the elevation angle. That is, the horizontal and vertical lengths of the virtual screen are converted into the azimuth angle (angle in the left-right direction) and the elevation angle (angle in the up-down direction) from the LiDAR system 10 mounted on the vehicle 20. The origin O (azimuth angle = 0° and elevation angle = 0°) means the direction parallel to the center line 24 in the fore-aft direction.

[0034] The auxiliary lines V0 and H0 intersect at the origin O in Fig. 4. The left and right sides of the auxiliary line V0 correspond to the left (l: left) and right (r: right) in the vehicle width direction. The upper and lower sides of the auxiliary line H0 correspond to the upper (u: up) and lower (d: down) of the horizontal plane passing through the center line 24 in the front-rear direction.

[0035] In Fig. 4, in addition to the auxiliary lines V0 and H0, a number of auxiliary lines Vl2, Vl1, Vh1, Vh2, Hd, and Hu are shown, and the angular intervals between the auxiliary lines are written in. The illumination range 13 occupies an elevation angle range of 20° above to 20° below, and an azimuth angle range of 65° left to 75° right. Generally, the azimuth angle range of the illumination range 13 is 120° to 140°.

[0036] (lens) 5A and 5B are perspective views of the front of the irradiation device 12 in Fig. 3 as viewed diagonally from above on the right and left. In addition, in the lens 58 constituting the irradiation-side optical system 36 in Fig. 3, the light source device 32 side and the opposite side thereof will be referred to as the upper side (or one end side) and the lower side (or the other end side), respectively. When the LiDAR system 10 is mounted on the vehicle 20, the upper side and the lower side of Fig. 3 are the upper side and the lower side of the LiDAR system 10 in the mounted state.

[0037] The irradiation device 12 is provided with an optical element with a narrow light distribution and an optical element with a wide light distribution separately. In Fig. 5A, an element with a reference numeral suffix n (n: narrow) indicates an optical element with a narrow light distribution, and an element with a reference numeral suffix w (w: wide) indicates an optical element with a wide light distribution.

[0038] For convenience of explanation, a three-axis coordinate system is illustrated. In Fig. 5A, the X-axis extends in the front-rear direction with the front side being positive, with the front and back sides of the irradiation device 12 being called the front side and the back side, respectively. The Y-axis extends in the left-right direction with the right side being positive when viewed from the front of the irradiation device 12. The Z-axis extends in the up-down direction with the top being positive when viewed from the front of the irradiation device 12.

[0039] The light source device 32 includes light sources 33n and 33w, which are separated from each other in the left-right direction. The light source 33w is located on the right side of the light source 33n in the left-right direction when viewed from the front. As will be seen from Fig. 7D described later, the light source 33n is located slightly forward of the light source 33w. The light sources 33n and 33w have optical axes extending in the up-down direction, and emit laser light toward the lens portions 59n and 59w, which serve as corresponding optical elements, respectively.

[0040] Single lens 58 has lens portions 59n, 59w integrally arranged in the left-right direction. A back surface 65 and a bottom surface 66 of lens 58 are common to lens portions 59n, 59w and are both formed as flat surfaces. A substrate (not shown) is attached to back surface 65. Lens portions 59n, 59w have substantially the same configuration, with only some differences in configuration.

[0041] Regarding the same configuration of the lens portions 59n and 59w, only the lens portion 59n will be described, and the lens portion 59w will be omitted. As the same configuration, the lens portion 59n has, from top to bottom, an incident surface 62n, an exit surface 63n, and an inclined protruding portion 64n. The incident surface 62n is formed as a circumferential part of a cylindrical side surface having a central axis parallel to the Y axis, and faces the exit surface of the light source 33 in the up-down direction. The exit surface 63n is formed as a part of a cylindrical side surface having a central axis extending in the up-down direction. The inclined protruding portion 64n protrudes obliquely downward in the radial direction from the lower end of the exit surface 63n.

[0042] Fig. 6A is a detailed perspective view of the irradiation device 12 including its internal structure. Fig. 6B and Fig. 6C are views taken along arrows F6B and F6C in Fig. 6A, respectively.

[0043] In FIG. 6A, a conical hole 68n is formed inside the incident surface 62n, with the central axis being the central axis of the cylindrical side surface of the exit surface 63n. T68n is the apex of the conical hole 68n. C33n is a vertical auxiliary line that overlaps with the optical axis of the light source 33n. E68n is a horizontal auxiliary line that passes through the apex T68n. C33n is a vertical auxiliary line that passes through the apex T68n.

[0044] The reflecting surface 69n is formed from at least a part of the circumferential direction of the conical side surface of the conical hole 68n. The apex angle of the conical hole 68n is, for example, 90°.

[0045] The differences between lens portions 59n and 59w will be described. Vertex T68w is located lower than vertex T68n in the up-down direction. Therefore, the height from bottom surface 66 of conical hole 68w is higher than that of conical hole 68n. Also, vertex T68w is located forward of vertex T68n in the front-to-rear direction. Therefore, the radius of the bottom surface of lens portion 59w is larger than that of lens portion 59n, and as a result, the light distribution angle range (azimuth angle range) of reflecting surface 69w is larger than the light distribution angle range of reflecting surface 69n, that is, lens portion 59w can generate a wider light distribution pattern than lens portion 59n.

[0046] It should be noted that the auxiliary line C33n is offset to the right of the auxiliary line C68n in the left-right direction when viewed from the front. This means that the amount of laser light emitted from the right half of the reflective surface 69n is greater than that from the left half when viewed from the front. In contrast, the auxiliary line C33w and the auxiliary line C68w are in the same position on the reflective surface 69w, so the amount of laser light emitted in the radial direction from the reflective surface 69w is equal on the left and right.

[0047] 6B and 6C, the conical holes 68n, 68w open as rear openings 71n, 71w, respectively, on the rear surface 65. The conical holes 68n, 68w open as bottom openings 70n, 70w, respectively, on the bottom surface 66. The radius of the bottom opening 70w is larger than the radius of the bottom opening 70n (FIG. 6C). Moreover, the protruding width of the inclined protruding portion 64w is larger than the protruding width of the inclined protruding portion 64n (FIG. 6B).

[0048] (Optical path of irradiated light) FIG. 7A shows the optical path of the laser light in the irradiation device 12. FIG. 7B, FIG. 7C, and FIG. 7D are views of the arrows F7A, F7B, and F7C in FIG. 7A, respectively. The laser lights In and Iw refer to the laser lights emitted by the light sources 33n and 33w, respectively. The laser lights In and Iw are both infrared light. In the drawings, a plurality of laser lights In and Iw extend from different positions from each of the light sources 33n and 33w that emit the laser light, but this is for the convenience of making the explanation easier to understand. Originally, the laser light is simply emitted from one point centered on the optical axis (emission axis) of the light source 33n and 33w in a divergent manner.

[0049] The operation of the lens portion 59w with a wide light distribution will be described first. Regarding the operation of the lens portion 59n, only the difference from the lens portion 59w will be described. The emission intensity of each of the light sources 33n and 33w is, for example, 350 watts (W).

[0050] The laser light Iw is emitted from the light source 33w and enters the entrance surface 62w while spreading slightly. The entrance surface 62w on the cylindrical side acts as a collimating lens. Therefore, after entering the entrance surface 62w, the laser light Iw descends in parallel in the vertical direction and hits the reflecting surface 69w.

[0051] The laser light Iw is totally reflected by the reflecting surface 69w and travels in each radiation direction of an emission direction at 90° to the incident direction. The laser light Iw reflected by the reflecting surface 69w is divided into an upper portion overlapping with the emission surface 63w and a lower portion overlapping with the inclined protruding portion 64w in the vertical range.

[0052] The laser light Iw reflected from the upper portion passes through the emission surface 63w in a straight line and continues in each radial direction, whereas the laser light Iw reflected from the lower portion is refracted by the inclined protruding portion 64w, changes direction obliquely downward, and continues in the radial direction obliquely downward.

[0053] The entire upper portion of the laser light Iw is emitted with uniform intensity in the radial direction centered on the Z axis. This laser light Iw corresponds to the emitted light with an elevation angle ranging from 10° on the upper side to 15° on the lower side in the light distribution pattern of Fig. 4. At this time, the exit surface 63w on the side surface of the cylinder acts as a collimating lens, and each laser light Iw emitted in each radial direction from the exit surface 63w proceeds while being suppressed from spreading.

[0054] Each of the laser beams Iw in the lower portion is refracted as it passes through the inclined protruding portion 64w, and after being refracted, it travels diagonally downward. The laser beams Iw refracted downward correspond to the emitted beams in the range below 15° in elevation angle of the light distribution pattern in Fig. 4. Note that, in the vicinity of the lower 15° of elevation angle, the laser beams Iw emitted from the emission surface 63w and the laser beams Iw emitted from the inclined protruding portion 64w may be mixed together.

[0055] Next, the laser light In emitted from the light source 33n will be described, focusing only on the differences between the laser light Iw. The optical axis (auxiliary line C33n) of the light source 33n is slightly shifted to the right from the apex T68n when viewed from the front of the lens 37n. Therefore, although the laser light In that passes through the entrance surface 62n serving as a collimator lens descends straight in the vertical direction, the amount of irradiation of the right half of the reflecting surface 69n on the cone side surface is greater than that of the left half.

[0056] As a result, on the reflecting surface 69n, the radiation intensity of the laser beam In radiated to the right becomes greater than the radiation intensity of the laser beam In radiated to the left (toward the lens portion 59w). This corresponds to the irradiation-side main optical axis 41 being biased toward the front-rear center line 24 with respect to the irradiation-side central optical axis 40 in FIG.

[0057] 8 shows, in a plan view, the illumination ranges 13n, 13w generated by the lens portions 59n, 59w of the lens 58, respectively. The main optical axis 77w in the illumination range 13w is on the central optical axis of the illumination range 13w, i.e., on the center line of the illumination range 13w. In contrast, the main optical axis 77n in the illumination range 13n is offset from the center line of the illumination range 13n to the opposite side to the lens portion 59w. The auxiliary lines Vl2, Vr2 in FIG. 8 correspond to the auxiliary lines Vl2, Vr2 in FIG. 4.

[0058] (Search range setting) 9A shows a right-side illumination range 13r that is set around the vehicle 20 including the front thereof by emitting laser light from an illumination device 12r mounted on the right front portion of the vehicle 20 while the vehicle 20 is traveling on a road. In fact, the LiDAR system 10 is mounted on the right end of the front portion of the vehicle 20 and is set to generate the illumination range 13r, for example, the light distribution pattern shown in FIG.

[0059] The auxiliary lines Vl2, V0, Vr1, and Vr2 extending in a clockwise radial direction in FIG. 9A correspond to the auxiliary lines Vl2, V0, Vr1, and Vr2 extending in a vertical direction in FIG.

[0060] 9A indicates the distance in meters (m) that the laser light from the irradiation device 12l can reach at or above the rated intensity. "deg" means the unit of angle "°."

[0061] FIG. 9B shows irradiation ranges 13r, 13l that are set in front of the vehicle 20 by emitting laser light from irradiation devices 12r, 12l mounted on the right and left front parts of the vehicle 20, respectively, while the vehicle 20 is traveling on a road.

[0062] 9B, auxiliary lines Vle and Vre are the boundary lines at the left and right ends of irradiation area 13l, respectively, and correspond to auxiliary lines Vr2 and Vl2 of irradiation area 13r. The sectorial range of auxiliary lines Vl2 to Vre at the circumferential angle is the range where irradiation areas 13l and 13r overlap.

[0063] (Modifications and Supplements) In the LiDAR system 10 of the embodiment, a flash method is adopted, but the irradiation method in the vehicle LiDAR system of the present invention is not limited to the flash method, and may be a scan method or the like.

[0064] In the LiDAR system 10, the emission surfaces 63n and 63w are both formed as a part of the circumferential direction of the cone side surface. However, when the LiDAR system 10 is mounted on the roof of a vehicle, the emission surfaces 63n and 63w may be formed as the entire circumferential direction of the cone side surface, and the laser light may be irradiated outward in the radial direction over the entire circumference of 360°.

[0065] In the LiDAR system 10, the lens 58 has two lens portions, 59n and 59w, as the first and second optical portions of the present invention. In the present invention, the lens 58 may have only one lens portion 59n as an optical element, or may have a total of three or more lens portions 59n and 59w. In that case, at least one of the lens portions 59w is an optical element that biases the optical axis of the light source 33n and the central axis of the reflecting surface 69n relative to each other, like the lens portion 59n. In addition, when the LiDAR system 10 has a plurality of lens portions 59w in the left-right direction of the front view, the heights of the apexes T69 of the reflecting surface 69 in each lens portion 59w can be made different from each other to make the individual light distribution ranges different from each other, or the overlapping ranges of the plurality of light distribution ranges can be adjusted.

[0066] The inclined protruding parts 64n, 64w of the LiDAR system 10 correspond to the refracting parts of the present invention. The refracting parts of the present invention do not have to be inclined protruding parts, but as long as they are formed on the lower side of the emission surfaces 63n, 63w (the up-down direction is defined as in the description of FIG. 5A) on the side surface of the lens 58 and are formed on a curved side surface that refracts the laser light reflected from the lower end of the reflecting surfaces 69n, 69w obliquely downward outside the radiation direction, the formation surface does not have to be limited to the surface of the inclined protruding parts 64n, 64w.

[0067] The illumination device 12 may be built into the housing of the headlamp 23 from the beginning. The manufacturer of the vehicle 20 can prepare the light receiving device 14 and the headlamp 23 including the illumination device 12 separately, rather than as a set, and install the LiDAR system 10 when manufacturing the vehicle 20.

[0068] In this LiDAR system 10, the emission surfaces 63n, 63w are formed on cylindrical side surfaces coaxial with the conical side surfaces of the reflecting surfaces 69n, 69w. This allows the emission surfaces 63n, 63w to function as collimating lenses for the laser light emitted in the radial direction from the emission surfaces 63n, 63w. The emission surfaces 63n, 63w can also be curved surfaces other than cylindrical side surfaces to make the light distribution in each radial direction non-uniform. [Explanation of symbols]

[0069] 10···LiDAR system, 12···illuminating device, 13···illumination range, 14···light-receiving device, 15···light-receiving range, 17···search range, 20···vehicle, 23···headlamp, 26···road surface, 28···target, 30···light source device, 33···light source, 36···illuminating optical system, 40···central optical axis of illuminating side, 41···main optical axis of illuminating side, 42···central optical axis of receiving side, 45···illuminated light, 46···reflected light, 50···light-receiving optical system, 58···lens, 62···incident surface, 63···exiting surface, 64···inclined protrusion, 66···bottom surface, 69···reflecting surface, 70···bottom opening.

Claims

1. An irradiation device that emits laser light toward a predetermined irradiation range; a light receiving device having a predetermined light receiving range including a range overlapping with the irradiation range as a search range, the light receiving device receiving the reflected light of the laser light from an object in the search range; A vehicle LiDAR system comprising: The irradiation device includes: A light source that emits the laser light; an optical unit having at least a part of a circumferential direction of a cone side surface, the apex of which is on the light source side and the central axis passing through the apex is biased with respect to the optical axis of the light source, as a reflecting surface, the optical unit reflecting the laser light from the light source incident from the apex side in a radial direction at the reflecting surface; A LiDAR system for a vehicle.

2. the optical unit has a lens that forms the conical side surface and has a conical cavity whose bottom surface is open at the other end side opposite to the one end side on the light source side, The lens is an incidence surface formed on the one end side as a lens surface of a collimating lens and on which the laser light from the light source is incident; an emission surface formed on the side surface of the cone so as to cover the cone side surface from the outside in the radiation direction, and emitting the laser light reflected by the reflection surface to the outside in the radiation direction; The vehicle LiDAR system of claim 1 ,

3. The vehicle LiDAR system of claim 2, wherein the lens further has a refracting emission portion formed on the side surface toward the other end side from the emission surface and refracts and emits the laser light reflected in the radial direction from the end of the reflecting surface on the other end side at an angle toward the other end side.

4. An irradiation device that emits laser light toward a predetermined irradiation range; a light receiving device having a predetermined light receiving range including a range overlapping with the irradiation range as a search range, the light receiving device receiving the reflected light of the laser light from an object in the search range; A vehicle LiDAR system comprising: The irradiation device includes: A plurality of light sources each having a parallel optical axis and emitting the laser light; a plurality of optical units provided corresponding to the respective light sources, each having at least a part of a circumferential direction of a cone side whose apex is on the corresponding light source side as a reflection surface, and reflecting the laser light from the corresponding light source incident from the apex side in a radiation direction at the reflection surface; Equipped with At least one of the plurality of optical units is a first optical unit, the central axis of which is offset with respect to an optical axis of the corresponding light source; A LiDAR system for a vehicle, wherein at least one of the plurality of optical units is a second optical unit whose central axis coincides with the optical axis of the corresponding light source.

5. the plurality of optical zones are formed within a single lens; Each optical unit has a conical cavity that forms the conical side surface and has a bottom surface that is open at the other end side opposite to the one end side on the light source side, Each optical section is an incidence surface formed on the one end side as a lens surface of a collimating lens and on which the laser light from the light source is incident; an emission surface formed on the side surface of the cone so as to cover the cone side surface from the outside in the radiation direction, and emitting the laser light reflected by the reflection surface to the outside in the radiation direction; The vehicle LiDAR system of claim 4 , further comprising:

6. The vehicle LiDAR system of claim 5, wherein each optical unit further has a refracting emission unit formed on the side surface toward the other end side from the emission surface and refracts and emits the laser light reflected in the radial direction from the end of the reflecting surface on the other end side at an angle toward the other end side.

7. The vehicle LiDAR system according to claims 1 to 6, which is mounted at the front of the vehicle and at an end in the vehicle width direction.

8. 8. The vehicle according to claim 7, wherein the illumination device is disposed within a housing of a headlamp, and the light receiving device is disposed outside the housing.

9. The LiDAR system for a vehicle according to any one of claims 4 to 6, which is mounted at a front part of a vehicle and at an end part in a vehicle width direction, A LiDAR system for a vehicle, wherein the first optical unit and the second optical unit are located on the inside and outside in the vehicle width direction.

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