Optical system, laser radar system and scanning method

Abstract

The invention provides an optical system, a laser radar system and a scanning method, and relates to the technical field of optics. The optical system comprises a light source used for emitting a regional light beam for detecting a target object; and the at least one micro lens array is used for dodging and angle-expanding the light beams, each micro lens array comprises a plurality of micro lens units, and the arrangement mode of the plurality of micro lens units is correspondingly set according to the dodging and angle-expanding direction of the light beams in the area. According to the method, the light beam is uniformly irradiated on the target object by utilizing the micro-lens array while the energy of the light source can be utilized to the maximum extent, the detection precision of the detection system is improved, the detection amount of scanning information of the transmitting end is effectively improved by further utilizing the light emitting mode of the light source, the ghost image of the transmitting end system is reduced, and the detection accuracy is improved. The detection efficiency of the detection system is effectively improved while the size of the system is reduced.

Description

Technical Field

[0001] The present application relates to the field of optical technology, and in particular to an optical system, a laser radar system and a scanning method. Background Art

[0002] LiDAR (Light Detection And Ranging) is a sensing device that uses active laser to detect the position, speed and other characteristic information of a target. It mainly obtains relevant information of the target by emitting laser signals to the target and analyzing the laser signals reflected by the target to achieve detection, identification and tracking of the target.

[0003] The existing laser radar system achieves the matching of transmitting and receiving signals mainly by transmitting point-to-point or single-line-to-point optical signals. Since this method transmits discrete point-line optical signals, there are dark areas between points or lines in the illuminated area of ​​the target object, and the existence of dark areas causes the reflected optical signal to be partially missing, affecting the detection accuracy. In addition, although the existing line-by-line scanning method can avoid the problem of missing scanning information, the mutual emission between the structural parts and the lenses and the lenses will cause the appearance of stray light. The signal crosstalk caused by the stray light will interfere and cause part of the effective signal in the reflected light signal to be annihilated, affecting the detection accuracy and system sensitivity. At present, in order to reduce the information loss caused by the dark area, a larger light source and its corresponding transmitting end lens are usually set to match the receiving chip with a higher receiving signal, but this will cause the overall setting of the laser radar to be larger and the cost is also higher.

[0004] In summary, it is difficult for existing laser radars to avoid the problem of partial loss of reflected light signals due to dark areas or stray light through point scanning and line scanning, which affects the detection accuracy. Summary of the invention

[0005] The present application provides an optical system, a laser radar system and a scanning method, which are used to solve the problem that it is difficult to avoid partial loss of reflected light signals due to dark areas or stray light through point scanning and line scanning in existing laser radars, thereby affecting detection accuracy.

[0006] In a first aspect, the present application provides an optical system, comprising:

[0007] A light source, used for emitting a regional light beam for detecting a target object;

[0008] And at least one micro lens array is used to perform light homogenization and angle expansion processing on the light beam, each of the micro lens arrays includes a plurality of micro lens units, and the arrangement of the plurality of micro lens units is set correspondingly according to the direction of light homogenization and angle expansion of the regional light beam.

[0009] In a possible design, a transmitting end lens is further included, which is used to diverge or collimate the regional light beam emitted by the light source; the horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy the following relationship:

[0010] HFOV / |R1| / D1≤16;

[0011] or,

[0012] HFOV / |R1| / D1≤8.

[0013] In a possible design, the horizontal curvature radius R1 of the microlens unit and the vertical curvature radius R2 of the microlens unit satisfy the following relationship:

[0014] |R1 / R2|≤10.

[0015] In a possible design, the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy the following relationship:

[0016] 50≤|R1 / D1|≤100;

[0017] The vertical curvature radius R2 and the vertical aperture D2 of the microlens unit satisfy the following relationship:

[0018] 50≤|R2 / D2|≤100.

[0019] In a possible design, the thickness of the microlens unit is a random thickness value, and the variation d0 of the random thickness value satisfies the following relationship with the preset thickness d:

[0020] |d0|≤1 / 5*d.

[0021] In a possible design, the horizontal radius of curvature of the microlens unit is a random value of the horizontal radius of curvature, and the maximum random value R1max and the minimum random value R1min of the horizontal radius of curvature among the random values ​​of the horizontal radius of curvature satisfy the following relationship:

[0022] 0.5≤R1max / R1min≤1.5;

[0023] The vertical curvature radius of the microlens unit is a vertical curvature radius random value, and the maximum vertical curvature radius random value R2max and the minimum vertical curvature radius random value R2min among the vertical curvature radius random values ​​satisfy the following relationship:

[0024] 0.5≤R2max / R2min≤1.5.

[0025] In a possible design, the horizontal center point of the microlens array is a random value of horizontal aperture, and the variation D3 of the random value of horizontal aperture satisfies the following relationship with the preset horizontal aperture D1:

[0026] |D3|≤1 / 3*D1;

[0027] The vertical center point of the microlens array is a vertical aperture random value, and the variation D4 of the vertical aperture random value satisfies the following relationship with the preset vertical aperture D2:

[0028] |D4|≤1 / 3*D2.

[0029] In a possible design, a transmitting end lens is also included, which is used to diverge or collimate the regional light beam emitted by the light source; the collimation degree α1 before uniform light, the collimation degree α2 after uniform light of the light source, the horizontal field of view angle HFOV of the transmitting end lens, the focal length F of the transmitting end lens, the number of single-row light sources C in the horizontal direction, and the size Le of a single light-emitting hole of the light source satisfy the following irradiation area relationship:

[0030] 1≤α2 / α1≤F*2tan(HFOV / 2) / C / Le;

[0031] in,

[0032] α1>0,1≤F*tan(HFOV / 2) / C / Le≤35;

[0033] or,

[0034] F*tan(HFOV / 2) / C / Le≤α2 / α1≤F*2tan(HFOV / 2) / C / Le.

[0035] In a possible design, it also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; the transmitting end lens and the microlens array are arranged in a bonded or non-bonded manner;

[0036] If the emitting end lens and the microlens array are arranged in close contact, the curvature of the rearmost surface of the emitting end lens is consistent with the curvature of the contact surface of the microlens array.

[0037] In a possible design, the focal length F1 of the microlens unit in the horizontal direction and the focal length F2 in the vertical direction satisfy the following relationship:

[0038] |F1 / F2|≤5.

[0039] In a possible design, the light source is used to simultaneously emit at least two regional light beams of preset shapes and perform cyclic scanning, and the multiple regional light beams of preset shapes are not adjacent to each other during the scanning process.

[0040] In a possible design, the light source is also used to emit a single row / column area light beam.

[0041] In a possible design, the light source is also used to emit a special-shaped area light beam for eliminating the distortion of the transmitting end lens.

[0042] In a possible design, when the regional light beam of the preset shape is a block-shaped regional light beam, the length m and width n of the regional light beam and the length M and width N of the light beam detected by the receiving chip of the laser radar system satisfy the following relationship:

[0043] m / M≥1, n / N≥1;

[0044] Among them, 1≤m≤8, 1≤n≤8.

[0045] In a second aspect, the present application provides a laser radar system, comprising: an optical system as described in any one of claims 1 to 10; and

[0046] a target object for reflecting the area beam emitted by the optical system;

[0047] A receiving end, used to receive the regional light beam reflected by the target object, wherein the area of ​​the regional light beam received by the receiving end is not less than the area of ​​the regional light beam emitted by the optical system;

[0048] Wherein, the receiving end includes a receiving end lens and a receiving chip;

[0049] The receiving end lens is used to focus the regional light beam reflected by the target object, and the receiving end lens and the transmitting end lens in the optical system are co-distorted;

[0050] The receiving chip is used to detect and receive the regional light beam after focusing processing.

[0051] In a possible design, the transmitting end lens distortion Fθ TX The receiver lens distortion Fθ RX Satisfies the following relationship:

[0052] 0.3≤|Fθ TX / Fθ RX |≤3;

[0053] or,

[0054] |Fθ TX / Fθ RX -1|≤0.1.

[0055] In a possible design, the total optical length L1 of the optical system and the total optical length L2 of the light source receiving end satisfy the following relationship:

[0056] L2 / L1≤3;

[0057] or,

[0058] 0.5<L2 / L1≤2;

[0059] The total optical length L1 of the optical system is used to identify the distance between the light source and the light emitting surface of the microlens array, and the total optical length L2 of the light source receiving end is used to identify the distance between the reflected light receiving surface of the receiving end lens and the receiving chip.

[0060] In a third aspect, the present application provides a laser radar scanning method, using the laser radar system as described in any one of claims 11 to 13, the method comprising:

[0061] The light source of the laser radar system is controlled to emit an area light beam of a preset shape.

[0062] In a possible design, when the regional light beam of the preset shape is a block-shaped regional light beam, the length m and width n of the regional light beam and the length M and width N of the light beam detected by the receiving chip of the laser radar system satisfy the following relationship:

[0063] m / M≥1, n / N≥1;

[0064] Among them, 1≤m≤8, 1≤n≤8.

[0065] In a possible design, the light source of the laser radar system is controlled to simultaneously emit at least two area light beams of preset shapes, and the multiple area light beams of preset shapes are always non-adjacent during the scanning process.

[0066] In one possible design, the light source of the lidar system is controlled to emit a single row / column of area light beams.

[0067] In one possible design, the light source of the laser radar system is controlled to emit a special-shaped area light beam for eliminating lens distortion at the transmitting end.

[0068] The optical system, laser radar system and scanning method provided by the present application are used to emit a regional light beam for detecting a target object by setting a light source; a transmitting end lens is used to diverge or collimate the regional light beam emitted by the light source; and at least one microlens array is used to perform uniform light expansion processing on the light beam, each of which includes a plurality of microlens units, and the arrangement of the plurality of microlens units is arranged in a corresponding manner according to the uniform light expansion direction of the regional light beam. Compared with the defects of point scanning and line scanning in the prior art, it is difficult to avoid the partial loss of reflected light signals caused by dark areas or stray light, which affects the detection accuracy. The present application uses the transmitting end lens and the microlens array to perform uniform light expansion processing on the regional light beam emitted by the light source, while ensuring that the energy of the light source can be maximized, and uses the microlens array to achieve illumination of the light detection area without dark areas, which is conducive to improving the detection accuracy of the detection system, and further uses the light emission mode of the light source to effectively improve the detection amount of the scanning information of the transmitting end, while reducing the ghost image of the transmitting end system, and effectively improves the detection efficiency of the detection system while reducing the system volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0070] Figure 1 A schematic diagram of an optical system application scenario provided in an embodiment of the present application;

[0071] Figure 2 Schematic diagram of the optical system structure provided in the embodiment of the present application Figure 1 ;

[0072] Figure 3 A schematic diagram of the microlens array structure provided in an embodiment of the present application;

[0073] Figure 4 Schematic diagram of the optical system structure provided in the embodiment of the present application Figure 2 ;

[0074] Figure 5 A schematic diagram of the structure of a laser radar system provided in an embodiment of the present application;

[0075] Figure 6 Schematic diagram of the lighting relationship between the light source and the receiving chip in the laser radar system provided in the embodiment of the present application Figure 1 ;

[0076] Figure 7Schematic diagram of the lighting relationship between the light source and the receiving chip in the laser radar system provided in the embodiment of the present application Figure 2 ;

[0077] Figure 8 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 1 ;

[0078] Fig. 9 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 2 ;

[0079] Fig.10 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 3 ;

[0080] Fig.11 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 4 ;

[0081] Fig.12 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 5 ;

[0082] Fig.13 A schematic diagram of the relationship between the light source lighting position and the light signal received by the receiving chip in the laser radar system provided in an embodiment of the present application;

[0083] Fig.14 A schematic diagram of the correspondence between the light source lighting area and the receiving chip lighting area in the laser radar system provided in an embodiment of the present application;

[0084] Fig.15 This is a simulation diagram of the energy level distribution received by the receiving chip of the existing laser radar system;

[0085] Fig.16 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 6 . DETAILED DESCRIPTION

[0086] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation methods described in the following exemplary embodiments do not represent all implementation methods consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the attached claims, rather than all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0087] When existing LiDAR systems are scanning, it is easy for the uneven light beam emitted by the light source to cause dark areas in the illuminated area of ​​the target object. As a result, the existence of the dark area causes the receiving end of the light source detector of the LiDAR system to be unable to fully receive the effective light signal of the target object. These incomplete light signals will cause missing scanning information, resulting in poor detection accuracy and low LiDAR transceiver matching efficiency.

[0088] Based on the above technical problems, the inventive concept of this application is to replace the existing point scanning and line scanning with surface scanning, realize the uniform light expansion of the regional light beam through a microlens array, and eliminate diffraction and compensate for dark areas by setting specific parameters to improve the uniform light expansion effect, aiming to solve the above technical problems of the prior art.

[0089] The specific application scenarios of this application are as follows:

[0090] Figure 1 Schematic diagram of an optical system application scenario provided in an embodiment of the present application. Figure 1 As shown, the optical system 101 emits a light beam to illuminate the target object 102, and the reflected light beam of the target object 102 is captured by the detector receiving end 103 to form an optical signal related to the target object 102, so that the target object 102 can be reversely inferred based on the optical signal, thereby realizing the scanning function of scanning detection equipment such as laser radar.

[0091] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0092] Figure 2 Schematic diagram of the optical system structure provided in the embodiment of the present application Figure 1 ; Figure 3 This is a schematic diagram of the microlens array structure provided in the embodiment of the present application. Figure 2 As shown, the optical system includes:

[0093] A light source, used for emitting a regional light beam for detecting a target object;

[0094] And at least one micro lens array is used to perform light homogenization and angle expansion processing on the light beam, each of the micro lens arrays includes a plurality of micro lens units, and the arrangement of the plurality of micro lens units is set correspondingly according to the light homogenization and angle expansion direction of the regional light beam.

[0095] Specifically, a regional light beam is emitted by a light source, and the regional light beam is composed of rows and columns. The shape of the area is not limited, and can be any shape such as a square, rectangle, triangle, etc., so that the lens distortion can be quickly determined according to the requirements of the applied lidar system to improve the matching efficiency of the lens; the number of regional light beams is also not limited, and can be one, two, three, four, etc., as long as multiple regional light beams emitted simultaneously are not adjacent or overlapping.

[0096] like Figure 3 As shown, the microlens array includes a plurality of microlens units of a block structure arranged in an array in both horizontal and vertical directions.

[0097] In another feasible implementation, the microlens array includes a combination of a microlens array for horizontal light uniformity and angle expansion and a microlens array for vertical light uniformity and angle expansion that are orthogonal to each other, and the combination may be arranged in contact with or not in contact with each other.

[0098] Furthermore, it also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; the horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy the following relationship:

[0099] HFOV / |R1| / D1≤16;

[0100] Preferably,

[0101] HFOV / |R1| / D1≤8.

[0102] Specifically, the setting parameters of the transmitting end lens and the microlens unit are conducive to the uniformity of the light beam energy, which can enable the light beam to obtain a better uniform light and angle expansion effect in the horizontal direction, and is conducive to the compensation of dark areas.

[0103] Furthermore, the horizontal curvature radius R1 of the microlens unit and the vertical curvature radius R2 of the microlens unit satisfy the following relationship:

[0104] |R1 / R2|≤10.

[0105] Specifically, the curvature radius parameter relationship of the microlens unit can better control the angle of light, improve the imaging capability of the system and increase the field of view, which is beneficial to the matching of the transmitting and receiving ends.

[0106] Furthermore, the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy the following relationship:

[0107] 50≤|R1 / D1|≤100;

[0108] The vertical curvature radius R2 and the vertical aperture D2 of the microlens unit satisfy the following relationship:

[0109] 50≤|R2 / D2|≤100.

[0110] Specifically, the single-row microlens unit arrays in the horizontal and vertical directions are replaced with block microlens unit arrays having curvature radius and aperture characteristics in both the horizontal and vertical directions to achieve the function of uniform light and angle expansion.

[0111] Furthermore, the thickness of the microlens unit is a random thickness value, and the variation d0 of the random thickness value satisfies the following relationship with the preset thickness d:

[0112] |d0|≤1 / 5*d.

[0113] Specifically, the random thickness value makes the thickness between multiple adjacent microlens units not uniform, but fluctuates within a certain range, thereby avoiding the diffraction effect caused by uniform thickness and greatly suppressing the diffraction effect.

[0114] Furthermore, the horizontal radius of curvature of the microlens unit is a random value of the horizontal radius of curvature, and the maximum random value R1max and the minimum random value R1min of the horizontal radius of curvature in the random value of the horizontal radius of curvature satisfy the following relationship:

[0115] 0.5≤R1max / R1min≤1.5;

[0116] The vertical curvature radius of the microlens unit is a vertical curvature radius random value, and the maximum vertical curvature radius random value R2max and the minimum vertical curvature radius random value R2min in the vertical curvature radius random value satisfy the following relationship:

[0117] 0.5≤R2max / R2min≤1.5.

[0118] Specifically, the curvature radii in the horizontal and vertical directions are set to random values ​​that fluctuate within a certain range, thereby avoiding the diffraction effect caused by the uniform curvature radius and greatly suppressing the diffraction effect.

[0119] Furthermore, the horizontal center point of the microlens array is a random value of horizontal aperture, and the variation D3 of the random value of horizontal aperture satisfies the following relationship with the preset horizontal aperture D4:

[0120] |D3|≤1 / 3*D4;

[0121] The vertical center point of the microlens array is a random value of the vertical aperture, and the variation D4 of the random value of the vertical aperture satisfies the following relationship with the preset vertical aperture D6:

[0122] |D4|≤1 / 3*D6.

[0123] Specifically, the horizontal center points and vertical center points of the microlens array are randomly arranged, which ensures the uniform light and angle expansion effect while helping to eliminate diffraction.

[0124] Furthermore, it also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; the collimation degree α1 before homogenization and the collimation degree α2 after homogenization of the light source and the horizontal field of view angle HFOV of the transmitting end lens, the focal length F of the transmitting end lens, the number of single-row light sources C in the horizontal direction, and the size Le of a single light-emitting hole of the light source satisfy the following irradiation area relationship:

[0125] 1≤α2 / α1≤F*2tan(HFOV / 2) / C / Le;

[0126] in,

[0127] α1>0,1≤F*tan(HFOV / 2) / C / Le≤35;

[0128] Preferably,

[0129] F*tan(HFOV / 2) / C / Le≤α2 / α1≤F*2tan(HFOV / 2) / C / Le.

[0130] Specifically, this setting parameter can make full and effective use of each light source in the horizontal direction, avoid energy loss, and thus improve the uniform light expansion effect.

[0131] Furthermore, the focal length F1 of the microlens unit in the horizontal direction and the focal length F2 in the vertical direction satisfy the following relationship:

[0132] |F1 / F2|≤5.

[0133] Specifically, since different focal lengths have different effects on the uniformity and angle expansion of the light beam, the setting of the focal length ratio range parameter is conducive to achieving uniformity of the light beam energy within a specific beam width range, thereby better improving the uniformity and angle expansion effect of the system.

[0134] Furthermore, it also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; the transmitting end lens and the microlens array are arranged in a bonded or non-bonded manner.

[0135] Figure 4 Schematic diagram of the optical system structure provided in the embodiment of the present application Figure 2 .like Figure 4 As shown, the emitting end lens and the microlens array are arranged in close contact with each other, and the curvature of the rearmost surface of the emitting end lens is consistent with the curvature of the contact surface of the microlens array.

[0136] Specifically, by fitting the transmitting end lens and the microlens array together, the total length of the flood scanning transmitting end can be effectively reduced, thereby reducing the total length of the entire optical system, which is conducive to the miniaturization design of the optical system. By setting the two fitting surfaces to have the same curvature, such as both convex or concave or flat structures, the matching degree after fitting is ensured to improve the uniform light expansion effect.

[0137] Preferably, since the transmitting end lens is usually also provided with an optical window for protection, the microlens array can be bonded to the optical window, or formed integrally with the optical window, which is also conducive to the miniaturized design of the optical system.

[0138] Furthermore, the light source is used to simultaneously emit at least two regional light beams of preset shapes and perform cyclic scanning, and the multiple regional light beams of the preset shapes are always non-adjacent during the scanning process.

[0139] Furthermore, the light source is also used to emit a single row / column regional light beam.

[0140] Furthermore, the light source is also used to emit a special-shaped area light beam for eliminating the distortion of the transmitting end lens.

[0141] Furthermore, when the regional beam of the preset shape is a block-shaped regional beam, the length m and width n of the regional beam and the length M and width N of the beam detected by the receiving chip of the laser radar system satisfy the following relationship:

[0142] m / M≥1, n / N≥1;

[0143] Among them, 1≤m≤8, 1≤n≤8.

[0144] The optical system provided in this embodiment is provided with a light source for emitting a regional light beam for detecting a target object; and at least one microlens array for performing uniform light expansion processing on the light beam, each of the microlens arrays includes a plurality of microlens units, and the arrangement of the plurality of microlens units is arranged in a manner corresponding to the uniform light expansion direction of the regional light beam, so that the regional light beam emitted by the light source is uniformly expanded by the emitting end lens and the microlens array, and the illumination of the dark area between the regions is achieved without losing the energy of the light source, thereby increasing the amount of scanning information captured by increasing the illuminated area of ​​the light source, which is beneficial to improving the detection accuracy of the detection system.

[0145] Figure 5 This is a schematic diagram of the structure of the laser radar system provided in the embodiment of the present application. Figure 5 As shown, the laser radar system includes:

[0146] Optical system;

[0147] and a target object for receiving and reflecting the area light beam emitted by the optical system;

[0148] A receiving end, used to receive the regional light beam reflected by the target object, wherein the area of ​​the regional light beam received by the receiving end is not less than the area of ​​the regional light beam emitted by the optical system;

[0149] Wherein, the receiving end includes a receiving end lens and a receiving chip;

[0150] The receiving end lens is used to focus the light beam in the area after being reflected by the target object, and the receiving end lens and the transmitting end lens in the optical system are co-distorted;

[0151] The receiving chip is used to detect and receive the regional light beam after focusing processing.

[0152] Pan-area scanning

[0153] The transmitting end includes a light source, a transmitting end lens and a microlens array.

[0154] Furthermore, the transmitting end lens distortion Fθ TX The receiver lens distortion Fθ RX Satisfies the following relationship:

[0155] 0.3≤|Fθ TX / Fθ RX |≤3;

[0156] or,

[0157] |Fθ TX / Fθ RX -1|≤0.1.

[0158] Specifically, the common distortion setting of the transmitting end lens and the receiving end lens can ensure that the transmitting and receiving ends match to ensure the detection efficiency of the system. Therefore, the distortion amount of the transmitting and receiving end lenses needs to be limited within a certain range to improve the matching efficiency of the transmitting and receiving ends.

[0159] Among them, the transmitting end lens distortion Fθ TX Satisfies the following formula:

[0160] Fθ TX =((Y-Y0) / Y0)*100%;

[0161] Where, Y is the actual image height of the transmitting end lens, and Y0 is the ideal image height of the transmitting end lens;

[0162] Receiver lens distortion Fθ RX Satisfies the following formula:

[0163] Fθ RX =((Y'-Y0') / Y0')*100%;

[0164] Where Y' is the actual image height of the receiving end lens, and Y0' is the ideal image height of the receiving end lens.

[0165] Furthermore, the total optical length L1 of the optical system and the total optical length L2 of the receiving end satisfy the following relationship:

[0166] L2 / L1≤3;

[0167] or,

[0168] 0.5<L2 / L1≤2;

[0169] The total optical length L1 of the optical system is used to identify the distance between the light source and the light emitting surface of the microlens array, and the total optical length L2 of the light source receiving end is used to identify the distance between the reflected light receiving surface of the receiving end lens and the receiving chip.

[0170] Specifically, the optical length ratio between the transmitting end and the receiving end is limited to improve the matching efficiency between the receiving end and the transmitting end of the system.

[0171] The laser radar system provided by the embodiment of the present application includes: a light source, a transmitting end lens and a microlens array; and a target object, which is used to receive and reflect the regional light beam emitted by the optical system; a receiving end, which is used to receive the regional light beam reflected by the target object, and the area of ​​the regional light beam received by the receiving end is not less than the area of ​​the regional light beam emitted by the optical system; wherein the receiving end includes a receiving end lens and a receiving chip; the receiving end lens is used to focus the regional light beam after being reflected by the target object, and the receiving end lens and the transmitting end lens in the optical system are co-distorted; the receiving chip is used to detect and receive the regional light beam after the focusing process, and the lighting method of the regional light beam can avoid the receiving chip receiving the low noise caused by the single-line lighting. The system can collect large optical information and reduce the information loss caused by the annihilation of effective signals; improve the matching efficiency of the transmitting and receiving ends through the common distortion of the transmitting and receiving end lenses, which is beneficial to the stability and miniaturization of the system; control the luminous angle and uniformity of the regional light beam emitted by the light source through the microlens array, and use the matching transmitting and receiving end lenses to enable the receiving chip to receive more complete information; through the uniform light expansion effect of the microlens array, a small area of ​​the light source lighting area corresponds to a large area of ​​the receiving chip lighting area, thereby compensating for the dark area caused by the pixel defects of the light source in the detection area, reducing the size of the light source while reducing the overall volume of the lidar system, which is beneficial to the miniaturization design of the device and reducing the configuration cost of the device.

[0172] Fig.15 This is a simulation diagram of the energy level distribution received by the receiving chip of the existing laser radar system. Fig.15As shown, under the influence of mutual reflection between lenses and structural parts in the laser radar system, when the light source in a certain area is turned on, a halo 1502 is formed around the imaging area 1501, which makes the energy level of the right half of the detection area higher, causing the receiving chip to have a higher background noise due to stray light, thereby reducing the system's transceiver efficiency.

[0173] In order to reduce the influence of stray light on the system's transceiver efficiency and ensure scanning efficiency, the present application also provides a laser radar scanning method, which uses a laser radar system, including:

[0174] The light source of the laser radar system is controlled to emit an area light beam of a preset shape.

[0175] Specifically, the preset shape of the regional light beam can be any shape. By uniformly expanding the angle of each light-emitting hole in the light source, regional scanning can be achieved, compensating for dark areas caused by pixel defects, increasing the detection range, and improving imaging quality. The preset shape is used to supplement the distortion caused by the lens, further reducing the lens cost, so as to achieve random area scanning and improve the efficiency of transmitting and receiving matching.

[0176] Furthermore, if the regional beam of the preset shape is a block-shaped regional beam, the length m and width n of the regional beam and the length M and width N of the beam detected by the receiving chip of the laser radar system satisfy the following relationship:

[0177] m / M≥1, n / N≥1;

[0178] Among them, 1≤m≤8, 1≤n≤8.

[0179] Specifically, the scanning area is increased by setting a block-shaped regional beam, thereby improving the scanning efficiency; by setting m / M≥1, n / N≥1, the regional beam area is made not larger than the beam area detected by the receiving chip, thereby reducing the signal light crosstalk at the end of the detector.

[0180] Furthermore, the light source of the laser radar system is controlled to simultaneously emit at least two regional light beams of preset shapes, and the multiple regional light beams of preset shapes are always non-adjacent during the scanning process.

[0181] Fig.16 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 6 .like Fig.16 As shown, two area light beams of preset shapes are respectively set in the first row of the left half area and the twelfth row of the right half area, and are lit cyclically from top to bottom so that the two are never adjacent or intersecting, thereby avoiding areas susceptible to stray light, lighting up areas with less stray light, and effectively reducing the impact of stray light on the system.

[0182] Furthermore, the light source of the laser radar system is controlled to emit a single row / column of regional light beams.

[0183] Specifically, the scanning area is increased by lighting up the entire row or column, and there is no crosstalk from light beams in other areas, thereby ensuring a high scanning efficiency for the entire LiDAR system.

[0184] Furthermore, the light source of the laser radar system is controlled to emit a special-shaped area light beam for eliminating the distortion of the transmitting end lens.

[0185] Specifically, for a LiDAR system in which the transmitting and receiving lenses do not share common distortion, by emitting special-shaped area beams, such as triangular area beams, the distortion effect can be eliminated through graphic transformation and the need to add distortion correction equipment can be avoided. This is conducive to the miniaturization of the LiDAR system and the reduction of system configuration costs.

[0186] The laser radar system of the present application is described in detail below in conjunction with specific embodiments, wherein the light source adopts a VCSEL light source and the receiving chip adopts a SPAD chip.

[0187] Figure 6 Schematic diagram of the lighting relationship between the light source and the receiving chip in the laser radar system provided in the embodiment of the present application Figure 1 .like Figure 6 As shown, the light source is provided with two non-adjacent square lighting areas m. After being diverged by the transmitting end lens in the laser radar system, the light beam is evenly spread and then hits the target object. The light beam reflected by the target object is focused by the receiving end lens and then detected and received by the receiving chip, thereby obtaining two non-adjacent square lighting areas M corresponding to the lighting areas of the light source; wherein the area m of the lighting area of ​​the light source is smaller than the area M of the lighting area of ​​the receiving chip.

[0188] The light holes in the light source are arranged in multiple channels. Four rows of light holes are arranged in each channel. Two adjacent rows of light holes are staggered and closely arranged in a triangular distribution. Each channel consists of two areas, and the area of ​​a single lit area is m.

[0189] Preferably, the light source is lit in a cycle mode, that is, the channels corresponding to the left edge area and the right edge area of ​​the light source are lit at the same time, and Figure 6 The remaining areas are illuminated in a cyclic manner from left to right on the left side and from right to left on the right side as shown by the middle arrow, while ensuring the consistency of the lighting positions of the light source and the receiving chip, turning them on and off at the same time, thereby effectively reducing optical crosstalk in different areas and ensuring scanning accuracy.

[0190] The overall divergence angle of the lidar system is 126°*96°, and the size ratio of the VCSEL light source to the SPAD chip is 1:3.

[0191] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0192] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0193] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0194] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm.

[0195] The distortion of the transmitting end lens is the same as that of the receiving end lens, that is, |Fθ TX / Fθ RX |=1. The matching efficiency of the transmitting and receiving ends is as high as 98%.

[0196] The total length L1 of the transmitting end is equal to the total length L2 of the receiving end, both of which are 28 mm.

[0197] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=2.8.

[0198] Figure 7 Schematic diagram of the lighting relationship between the light source and the receiving chip in the laser radar system provided in the embodiment of the present application Figure 2 .like Figure 7 As shown, the light source is provided with two non-adjacent rectangular lighting areas n. After being diverged by the transmitting end lens in the laser radar system, the light beam is evenly spread and then hits the target object. The light beam reflected by the target object is focused by the receiving end lens and then detected and received by the receiving chip, thereby obtaining two non-adjacent rectangular lighting areas N corresponding to the lighting areas of the light source; wherein, the area n of the lighting area of ​​the light source is smaller than the area N of the lighting area of ​​the receiving chip.

[0199] The light holes in the light source are arranged in multiple channels. Two rows of light holes are arranged in each channel. Two adjacent rows of light holes are staggered and closely arranged in a triangular distribution. Each channel consists of two areas, and the area of ​​a single lit area is n.

[0200] Preferably, the light source is lit in a cycle mode, that is, the channels corresponding to the left edge area and the right edge area of ​​the light source are lit at the same time, and Figure 7 The remaining areas are illuminated in a circular manner from top to bottom as shown by the middle arrow, while ensuring the consistency of the lighting positions of the light source and the receiving chip, turning them on and off at the same time, thereby effectively reducing optical crosstalk in different areas and ensuring scanning accuracy.

[0201] The overall divergence angle of the lidar system is 125.5°*96°, and the size ratio of the VCSEL light source to the SPAD chip is 1:3.

[0202] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0203] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0204] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0205] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=125.5°.

[0206] The distortion of the transmitting end lens is the same as that of the receiving end lens, that is, |Fθ TX / Fθ RX |=1. The matching efficiency of the transmitting and receiving ends is as high as 98%.

[0207] The total length L1 of the transmitting end is equal to the total length L2 of the receiving end, both of which are 30 mm.

[0208] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=2.8.

[0209] Figure 8 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 1 .like Figure 8 As shown, the light source is provided with four non-adjacent lighting areas. After being diverged by the transmitting end lens in the laser radar system, the light beam is evenly spread and then hits the target object. The light beam reflected by the target object is focused by the receiving end lens and then detected and received by the receiving chip to obtain four non-adjacent lighting areas corresponding to the lighting areas of the light source; wherein the area of ​​the lighting area of ​​the light source is smaller than the area of ​​the lighting area of ​​the receiving chip.

[0210] The light-emitting holes in the light source are arranged in 32 channels, and three rows of light-emitting holes are arranged in each channel. The light-emitting holes in two adjacent rows are staggered and closely arranged in a triangular distribution, and each channel is composed of four areas.

[0211] Preferably, the light source is lit in a cycle mode, lighting up the channels corresponding to the areas on both sides of the light source at the same time, and Figure 8The remaining areas are illuminated in a cyclic manner from left to right on the left side and from right to left on the right side as shown by the middle arrow, while ensuring the consistency of the lighting positions of the light source and the receiving chip, turning them on and off at the same time, thereby effectively reducing optical crosstalk in different areas and ensuring scanning accuracy.

[0212] The overall divergence angle of the lidar system is 120°*90°, and the size ratio of the VCSEL light source to the SPAD chip is 1:3.

[0213] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0214] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0215] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0216] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=120°.

[0217] The distortion of the transmitting end lens is the same as that of the receiving end lens, that is, |Fθ TX / Fθ RX |=1. The matching efficiency of the transmitting and receiving ends is as high as 98%.

[0218] The total length L1 of the transmitting end is not equal to the total length L2 of the receiving end. The total length of L1 is 22mm and the total length of L2 is 28mm.

[0219] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=3.2.

[0220] Fig. 9 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 2 .like Fig. 9 As shown, the light source is provided with two non-adjacent but same-column lighting areas. After being diverged by the transmitting end lens in the laser radar system, the light beam is evenly diffused by the microlens array and then hits the target object. The light beam reflected by the target object is then focused by the receiving end lens and detected and received by the receiving chip, thereby obtaining two non-adjacent but same-column lighting areas corresponding to the lighting areas of the light source; wherein the area of ​​the lighting area of ​​the light source is smaller than the area of ​​the lighting area of ​​the receiving chip.

[0221] The light-emitting holes in the light source are arranged in 24 channels, and two rows of light-emitting holes are arranged in each channel. The light-emitting holes in two adjacent rows are staggered and closely arranged in a triangular distribution, and each channel is composed of four areas.

[0222] Preferably, the light source is lit in a cycle mode, lighting up the channels corresponding to the single-side area of ​​the light source at the same time, and Fig. 9 The remaining areas are illuminated in a cyclic manner from left to right as shown by the middle arrow, while ensuring the consistency of the lighting positions of the light source and the receiving chip, turning them on and off at the same time, thereby effectively reducing optical crosstalk in different areas and ensuring scanning accuracy.

[0223] The overall divergence angle of the lidar system is 128°*96°, and the size ratio of the VCSEL light source to the SPAD chip is 1:4.

[0224] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0225] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0226] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0227] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=128°.

[0228] The distortion of the transmitting end lens is the same as that of the receiving end lens, that is, |Fθ TX / Fθ RX |=1. The matching efficiency of the transmitting and receiving ends is as high as 96%.

[0229] The total length L1 of the transmitting end is not equal to the total length L2 of the receiving end. The total length of L1 is 24mm and the total length of L2 is 30mm.

[0230] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=3.5.

[0231] Fig.10 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 3 .like Fig.10 As shown, the light source is provided with two non-adjacent and different-column lighting areas. After being diverged by the transmitting end lens in the laser radar system, the light beam is evenly diffused by the microlens array and then hits the target object. The light beam reflected by the target object is focused by the receiving end lens and then detected and received by the receiving chip to obtain two non-adjacent and different-column lighting areas corresponding to the light source lighting area; wherein the area of ​​the light source lighting area is smaller than the area of ​​the receiving chip lighting area, and the microlens array is fitted with the transmitting end lens to reduce the total length of the transmitting end.

[0232] The light-emitting holes in the light source are arranged in 24 channels, each channel is provided with a row of light-emitting holes, and each channel is composed of two areas.

[0233] Preferably, the light source is lit in a cycle mode, lighting up the channels corresponding to the areas on both sides of the light source at the same time, and Fig.10 The remaining areas are illuminated in a circular manner from top to bottom as shown by the middle arrow, while ensuring the consistency of the lighting positions of the light source and the receiving chip, turning them on and off at the same time, thereby effectively reducing optical crosstalk in different areas and ensuring scanning accuracy.

[0234] The overall divergence angle of the lidar system is 126°*96°, and the size ratio of the VCSEL light source to the SPAD chip is 1:3.

[0235] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0236] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0237] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0238] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=126°.

[0239] The distortion of the transmitting end lens is the same as that of the receiving end lens, that is, |Fθ TX / Fθ RX |=1. The matching efficiency of the transmitting and receiving ends is as high as 99%.

[0240] The total length L1 of the transmitting end is not equal to the total length L2 of the receiving end. The total length of L1 is 22mm and the total length of L2 is 28mm.

[0241] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=2.5.

[0242] Fig.11 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 4 .like Fig.11As shown, the light source is provided with a single column of lighting areas. After being diverged by the transmitting end lens in the laser radar system, it is evenly lighted and expanded by the microlens array and then hits the target object. The light beam reflected by the target object is then focused by the receiving end lens and detected and received by the receiving chip to obtain multiple columns of lighting areas corresponding to the lighting areas of the light source; wherein the area of ​​the lighting area of ​​the light source is smaller than the area of ​​the lighting area of ​​the receiving chip.

[0243] The light holes in the light source are arranged in multiple channels, and two rows of light holes are arranged in each channel. Each row is composed of four columns of light holes, and one column of the light source is lit each time.

[0244] Preferably, the light source is lit in a cycle mode, according to Fig.11 The remaining areas are illuminated in turn in a single-row lighting cycle from left to right as indicated by the middle arrow.

[0245] The size ratio of the VCSEL light source and the SPAD chip of the overall lidar system is 1:2.1.

[0246] The microlens unit homogenizes the horizontal light beam, and the value range thereof satisfies: 2≤|microlens unit curvature radius R1 / microlens unit aperture D1|≤100, preferably, 5≤|microlens unit curvature radius R1 / microlens unit aperture D1|≤50.

[0247] The thickness of the plurality of microlens units is random, and the random range is ≤1 / 3*preset microlens thickness d. Preferably, the random range is ≤1 / 5*preset microlens thickness d.

[0248] The curvature radii of multiple microlens units in the horizontal direction are randomly designed, and the random range is 1≤R1max / R1min≤1.5.

[0249] The vertical curvature radii of multiple microlens units are randomly designed, and the random range is 1≤R2max / R2min≤1.5.

[0250] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0251] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0252] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0253] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=126°.

[0254] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=4.2.

[0255] Fig.12 Schematic diagram of the light source lighting position in the laser radar system provided in the embodiment of the present application Figure 5 .like Fig.12 As shown, the light source is provided with a single row of lighting areas. After being diverged by the transmitting end lens in the laser radar system, it is evenly lighted and expanded by the microlens array and then hits the target object. The light beam reflected by the target object is then focused by the receiving end lens and detected and received by the receiving chip to obtain multiple rows of lighting areas corresponding to the lighting areas of the light source; wherein the area of ​​the lighting area of ​​the light source is smaller than the area of ​​the lighting area of ​​the receiving chip.

[0256] The light holes in the light source are arranged in multiple channels, each channel is provided with three rows of light holes, each row is composed of eight columns of light holes, and one row of light sources is lit each time.

[0257] Preferably, the light source is lit in a cycle mode, according to Fig.12 The remaining areas are illuminated in a single row lighting cycle from top to bottom as indicated by the middle arrow.

[0258] The size ratio of the VCSEL light source and the SPAD chip of the overall lidar system is 1:2.2.

[0259] The microlens unit homogenizes the vertical light beam, and the value range thereof satisfies: 2≤|microlens unit curvature radius R2microlens unit aperture D2|≤70, preferably, 5≤|microlens unit curvature radius R2 / microlens unit aperture D2|≤30.

[0260] The thickness of the plurality of microlens units is random, and the random range is ≤1 / 3*preset microlens thickness d. Preferably, the random range is ≤1 / 5*preset microlens thickness d.

[0261] The curvature radii of multiple microlens units in the horizontal direction are randomly designed, and the random range is 1≤R1max / R1min≤1.5.

[0262] The vertical curvature radii of multiple microlens units are randomly designed, and the random range is 1≤R2max / R2min≤1.5.

[0263] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0264] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0265] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0266] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=96°.

[0267] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=5.

[0268] Fig.13 This is a schematic diagram of the relationship between the light source lighting position and the light signal received by the receiving chip in the laser radar system provided in the embodiment of the present application. Fig.13 As shown, the light source is provided with an arc-shaped lighting area. After being collimated by the transmitting end lens in the laser radar system, it is evenly lighted and expanded by the microlens array and then hits the target object. The light beam reflected by the target object is then focused by the receiving end lens and detected and received by the receiving chip to obtain an arc-shaped light signal corresponding to the lighting area of ​​the light source.

[0269] The light-emitting holes in the light source are arranged in multiple channels, and two rows of light-emitting holes are arranged in each channel. The light-emitting holes in two adjacent rows are staggered and closely arranged in a triangular distribution, and each channel consists of one area.

[0270] The size ratio of the VCSEL light source to the SPAD chip of this lidar system is 1:3.

[0271] The thickness of the plurality of microlens units is random, and the random range is ≤1 / 3*preset microlens thickness d. Preferably, the random range is ≤1 / 5*preset microlens thickness d.

[0272] The curvature radii of multiple microlens units in the horizontal direction are randomly designed, and the random range is 1≤R1max / R1min≤1.5.

[0273] The vertical curvature radii of multiple microlens units are randomly designed, and the random range is 1≤R2max / R2min≤1.5.

[0274] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0275] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0276] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0277] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=124°.

[0278] The distortion of the transmitting end lens is different from that of the receiving end lens, |Fθ TX / Fθ RX |=1:1.05.

[0279] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=3.1.

[0280] Fig.14 This is a schematic diagram of the corresponding relationship between the light source lighting area and the receiving chip lighting area in the laser radar system provided in the embodiment of the present application. Fig.14 As shown, the light source can be provided with a lighting area of ​​any shape, such as an arc-shaped lighting area. There is an unlit dark area between adjacent light-emitting holes. After being collimated by the transmitting end lens in the laser radar system, it is evenly lighted and expanded by the microlens array and then hits the target object. The light beam reflected by the target object is then focused by the receiving end lens and detected and received by the receiving chip to obtain an arc-shaped lighting area corresponding to the lighting area of ​​the light source. In the arc-shaped lighting area of ​​the receiving chip, there is no dark area between two adjacent light-emitting points.

[0281] The light holes in the light source are arranged in multiple channels, each of which can be lit arbitrarily, and the light shape can match the distortion of the transmitting end.

[0282] The size ratio of the VCSEL light source to the SPAD chip of this lidar system is 1:1.5.

[0283] The thickness of the plurality of microlens units is random, and the random range is ≤1 / 3*preset microlens thickness d. Preferably, the random range is ≤1 / 5*preset microlens thickness d.

[0284] The curvature radii of multiple microlens units in the horizontal direction are randomly designed, and the random range is 1≤R1max / R1min≤1.5.

[0285] The vertical curvature radii of multiple microlens units are randomly designed, and the random range is 1≤R2max / R2min≤1.5.

[0286] The horizontal center points of multiple microlens units are randomly arranged, and the horizontal center points are randomly arranged, and the random range is ≤1 / 3*preset horizontal aperture D4.

[0287] The vertical center points of multiple microlens units are randomly arranged, and the vertical center points are randomly arranged, with a random range of ≤1 / 3*preset vertical aperture D6.

[0288] The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy HFOV / R1 / D1≤16.

[0289] Among them, 0.005mm≤D1≤1mm; 0.1mm≤R1≤20mm; HFOV=124°.

[0290] The distortion of the transmitting end lens is different from that of the receiving end lens, |Fθ TX / Fθ RX |=1:1.05.

[0291] The collimation degree of the laser radar system after homogenization is α2 / the collimation degree before homogenization is α1=3.1.

[0292] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0293] Those skilled in the art can understand that in the description of the embodiments of the present application, the term "and / or" merely represents an association relationship that describes the associated objects, indicating that three relationships may exist. For example, A and / or B may represent three situations: A exists alone, A and B exist at the same time, and B exists alone. In addition, the term "at least one" represents any combination of at least two of any one or more of a plurality of. For example, at least one of A, B, and C may represent any one or more elements selected from a set that communicates A, B, and C. In addition, the term "plurality" means two or more, unless otherwise precisely and specifically specified.

[0294] In the description of the embodiment of the present application, the terms "first", "second", "third", "fourth", etc. (if present) are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0295] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical system, characterized in that: include: A light source, used for emitting a regional light beam for detecting a target object; And at least one microlens array is used to perform light homogenization and angle expansion processing on the light beam, each of the microlens arrays includes a plurality of microlens units, and the arrangement of the plurality of microlens units is set corresponding to the direction of light homogenization and angle expansion of the regional light beam.

2. The optical system according to claim 1, characterized in that It also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; The horizontal field of view HFOV of the transmitting end lens and the horizontal curvature radius R1 and horizontal aperture D1 of the microlens unit satisfy the following relationship: HFOV / |R1| / D1≤16.

3. The optical system according to claim 1, characterized in that The horizontal curvature radius R1 of the microlens unit and the vertical curvature radius R2 of the microlens unit satisfy the following relationship: |R1 / R2|≤10.

4. The optical system according to claim 1, characterized in that The horizontal curvature radius R1 and the horizontal aperture D1 of the microlens unit satisfy the following relationship: 50≤|R1 / D1|; The vertical curvature radius R2 and the vertical aperture D2 of the microlens unit satisfy the following relationship: 50≤|R2 / D2|.

5. The optical system according to claim 1, characterized in that The thickness of the microlens unit is a random thickness value, and the variation d0 of the random thickness value satisfies the following relationship with the preset thickness d: |d0|≤1 / 5*d.

6. The optical system according to claim 1, characterized in that The horizontal radius of curvature of the microlens unit is a random value of the horizontal radius of curvature, and the maximum random value R1max and the minimum random value R1min of the horizontal radius of curvature among the random values ​​of the horizontal radius of curvature satisfy the following relationship: 0.5≤R1max / R1min.

7. The optical system according to claim 1, characterized in that The horizontal center point of the microlens array is a random value of horizontal aperture, and the variation D3 of the random value of horizontal aperture satisfies the following relationship with the preset horizontal aperture D1: |D3|≤1 / 3*D1; The vertical center point of the microlens array is a vertical aperture random value, and the variation D4 of the vertical aperture random value satisfies the following relationship with the preset vertical aperture D2: |D4|≤1 / 3*D2.

8. The optical system according to claim 1, characterized in that It also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; The collimation degree α1 before homogenization and the collimation degree α2 after homogenization of the light source satisfy the following irradiation area relationship with the horizontal field of view HFOV of the transmitting end lens, the focal length F of the transmitting end lens, the number of single-row light sources C in the horizontal direction, and the size Le of a single light-emitting hole of the light source: 1≤α2 / α1≤F*2tan(HFOV / 2) / C / Le; in, α1>0, 1≤F*tan(HFOV / 2) / C / Le≤35.

9. The optical system according to claim 1, characterized in that It also includes a transmitting end lens, which is used to diverge or collimate the regional light beam emitted by the light source; the transmitting end lens and the microlens array are arranged in a bonded or non-bonded manner; If the emitting end lens and the microlens array are arranged in close contact, the curvature of the rearmost surface of the emitting end lens is consistent with the curvature of the contact surface of the microlens array.

10. The optical system according to claim 1, characterized in that The focal length F1 of the microlens unit in the horizontal direction and the focal length F2 in the vertical direction satisfy the following relationship: |F1 / F2|≤5.

11. The optical system according to claim 1, characterized in that The light source is used to simultaneously emit at least two regional light beams of preset shapes and perform cyclic scanning, and the multiple regional light beams of preset shapes are always non-adjacent during the scanning process.

12. The optical system according to claim 1, characterized in that The light source is also used to emit a single row / column regional light beam.

13. The optical system according to claim 1, characterized in that The light source is also used to emit a special-shaped area light beam for eliminating the distortion of the transmitting end lens.

14. The optical system according to any one of claims 11 to 13, characterized in that: When the regional light beam of the preset shape is a block-shaped regional light beam, the length m and width n of the regional light beam and the length M and width N of the light beam detected by the receiving chip of the laser radar system satisfy the following relationship: m / M≥1, n / N≥1; Among them, 1≤m≤8, 1≤n≤8.

15. A laser radar system, characterized in that: include: An optical system as claimed in any one of claims 1 to 10; and a target object for reflecting the area beam emitted by the optical system; A receiving end, used to receive the regional light beam reflected by the target object, wherein the area of ​​the regional light beam received by the receiving end is not less than the area of ​​the regional light beam emitted by the optical system; Wherein, the receiving end includes a receiving end lens and a receiving chip; The receiving end lens is used to focus the regional light beam reflected by the target object, and the receiving end lens and the transmitting end lens in the optical system are co-distorted; The receiving chip is used to detect and receive the regional light beam after focusing processing.

16. The laser radar system according to claim 15, characterized in that: The transmitting end lens distortion Fθ TX The receiver lens distortion Fθ RX Satisfies the following relationship: 0.3≤|Fθ TX / Fθ RX |≤3。 17. The laser radar system according to claim 15, characterized in that: The total optical length L1 of the optical system and the total optical length L2 of the receiving end satisfy the following relationship: L2 / L1≤3; The total optical length L1 of the optical system is used to identify the distance between the light source and the light-emitting surface of the microlens array, and the total optical length L2 of the receiving end is used to identify the distance between the reflected light receiving surface of the receiving end lens and the receiving chip.

18. A laser radar scanning method, characterized in that: Using the laser radar system as described in any one of claims 11 to 13, the method comprises: The light source of the laser radar system is controlled to emit an area light beam of a preset shape.

19. The method according to claim 18, characterized in that When the regional light beam of the preset shape is a block-shaped regional light beam, the length m and width n of the regional light beam and the length M and width N of the light beam detected by the receiving chip of the laser radar system satisfy the following relationship: m / M≥1, n / N≥1; Among them, 1≤m≤8, 1≤n≤8.

20. The method according to claim 18, characterized in that The light source of the laser radar system is controlled to simultaneously emit at least two regional light beams of preset shapes, and the multiple regional light beams of preset shapes are always non-adjacent during the scanning process.

21. The method according to claim 18, characterized in that The light source of the laser radar system is controlled to emit a single row / column area light beam.

22. The method according to claim 18, characterized in that The light source of the laser radar system is controlled to emit a special-shaped area light beam for eliminating the distortion of the transmitting end lens.

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