Lidar and carrier

Abstract

Provided in the present disclosure are a LiDAR, comprising an optical transceiving module and a scanning module. The optical transceiving module comprises an emission unit, an emission lens unit, a receiving lens unit and a receiving unit, wherein the emission unit is configured to generate detection light; the emission lens unit is configured to transmit the detection light; the receiving lens unit is separated from the emission lens unit; the receiving lens unit is configured to transmit echo light formed by means of the detection light being reflected by an object; and the receiving unit comprises a two-dimensional array detector. The scanning module is configured to receive the detection light and emit same outside the LiDAR and receive the echo light and emit same to the optical transceiving module.

Description

LiDAR and vehicles

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on November 17, 2023, with application number 202311545717.X, and the Chinese patent application filed with the State Intellectual Property Office of China on November 17, 2023, with application number 202323128741.1, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the field of laser radar, and in particular to a laser radar and a vehicle. Background Art

[0003] LiDAR is a commonly used distance-measuring sensor. Its long detection range, high resolution, and minimal environmental interference make it widely used in autonomous driving, intelligent robotics, and drones. Autonomous driving technology has advanced rapidly in recent years, and LiDAR, as its core distance-measuring sensor, has become indispensable.

[0004] The laser radar can reflect the light beam through the reflective surface of the scanning module to form a scanning beam for spatial scanning. The scanning module for the laser radar can realize the scanning beam scanning within the laser radar field of view through the reciprocating motion of the reflective surface.

[0005] The relatively large field of view (FOV) of each detector in existing LiDARs results in weaker target resolution. Reducing the FOV to improve target resolution could worsen the aberrations of the LiDAR's optical system, potentially increasing production complexity and costs. Summary of the Invention

[0006] The embodiments provided in the present disclosure can improve the ability of laser radar to distinguish targets, improve aberrations, and reduce production difficulty and production costs.

[0007] In a first aspect, the present disclosure provides a laser radar, comprising: an optical transceiver module and a scanning module. The optical transceiver module comprises: a transmitting unit, a transmitting lens unit, a receiving lens unit, and a receiving unit. The transmitting unit is configured to generate detection light. The transmitting lens unit is configured to transmit the detection light. The receiving lens unit is separated from the transmitting lens unit, and the receiving lens unit is configured to transmit the echo light formed by the detection light reflected by an object. The receiving unit comprises: a two-dimensional array detector, and the two-dimensional array detector is configured to detect the echo light passing through the receiving lens unit. The scanning module is configured to receive the detection light emitted to the outside of the laser radar, and receive the echo light emitted to the optical transceiver module.

[0008] Optionally, the transmitting lens unit includes a reflector and a transmitting lens. The transmitting lens includes at least one transmitting lens. The reflector is configured to reflect the detection light toward the scanning module.

[0009] Optionally, the receiving lens unit includes a receiving lens. The receiving lens includes at least one receiving lens.

[0010] Optionally, the focal length of the receiving lens is determined based on the interval between adjacent pixels in the two-dimensional array detector and the angular resolution of the laser radar.

[0011] Optionally, the focal length of the receiving lens is not greater than the focal length of the transmitting lens of the transmitting lens unit.

[0012] Optionally, the receiving component is located between the transmitting component and the scanning module. The transmitting component includes: the transmitting unit and the transmitting lens unit. The receiving component includes: the receiving unit and the receiving lens unit.

[0013] Optionally, the size of pixels in the two-dimensional array detector is greater than the optical parameters of the receiving lens.

[0014] Optionally, the receiving aperture of the receiving lens is greater than 8 millimeters (mm).

[0015] Optionally, the F number of the receiving lens is less than 4.

[0016] Optionally, the laser of the transmitting unit and the two-dimensional array detector of the receiving unit are arranged on the same circuit board.

[0017] Optionally, the optical transceiver module further includes a support member, and at least the transmitting lens unit is fixed to the support member.

[0018] Optionally, the emitting lens unit and the spectroscopic unit are both fixed to the support member.

[0019] Optionally, the optical transceiver module further includes: a receiving lens support, the receiving lens is fixed to the receiving lens support, and the receiving lens support is movably connected to the support.

[0020] Optionally, a plurality of focusing marks are provided on a circuit board that fixes the two-dimensional array detector.

[0021] Optionally, the receiving lens unit, the transmitting lens unit and the spectroscopic unit are all fixed to the support.

[0022] Optionally, the receiving unit includes a two-dimensional array detector, the two-dimensional array detector includes multiple detection areas, and the multiple detection areas correspond to the multiple lasers of the transmitting unit.

[0023] Optionally, the plurality of detection areas correspond one-to-one to the plurality of lasers of the emitting unit.

[0024] Optionally, the two-dimensional array detector further includes a compensation area, wherein the compensation area surrounds the plurality of detection areas.

[0025] Optionally, the receiving unit includes a plurality of two-dimensional array detectors, and the plurality of two-dimensional array detectors correspond one-to-one to the plurality of lasers of the transmitting unit.

[0026] Optionally, the plurality of two-dimensional array detectors are arranged in an array, with adjacent columns of two-dimensional array detectors being staggered along the column direction, or adjacent rows of two-dimensional array detectors being staggered along the row direction.

[0027] Optionally, the two-dimensional array detector includes a plurality of pixels.

[0028] Optionally, at least one pixel among the plurality of pixels includes a plurality of detection elements.

[0029] Optionally, each pixel of the plurality of pixels includes a plurality of detection elements.

[0030] Optionally, the detection element is a single-photon detection element.

[0031] Optionally, the optical transceiver module further includes a spectrometer configured to transmit the detection light transmitted by the transmitting lens unit to the scanning module, and transmit the echo light transmitted by the scanning module to the receiving lens unit.

[0032] Optionally, the light splitting unit includes a polarization light splitting element and a wave plate, wherein the wave plate is located in the optical path between the polarization light splitting element and the scanning module.

[0033] Optionally, the wave plate is attached to a surface of the polarization beam splitting element facing the scanning module.

[0034] Optionally, the scanning module includes a polygonal mirror. The polygonal mirror includes multiple reflective surfaces, each of which rotates around a rotation axis. The angles between different reflective surfaces and the rotation axis are partially the same.

[0035] Optionally, the polygonal mirror has an even number of reflecting surfaces, wherein adjacent reflecting surfaces have different angles with the rotation axis, and spaced reflecting surfaces have the same angle with the rotation axis.

[0036] In a second aspect, a vehicle is provided, comprising the laser radar of the first aspect and a connector, wherein the connector is used to connect the laser radar to the vehicle.

[0037] Optionally, the vehicle includes at least one of a vehicle, a ship, an aircraft, or a robot.

[0038] Compared with the prior art, the technical solution disclosed in the present invention has the advantages described below.

[0039] In the technical solution disclosed in the present invention, a two-dimensional array detector is used in the receiving unit to receive the echo light. In this way, the receiving field of view angle corresponding to each detector in the laser radar can be effectively reduced, which is beneficial to improving the optical resolution of the laser radar optical system, and further beneficial to improving the ability of the laser radar to distinguish targets. For the two-dimensional array detector, the optical transceiver module uses separate transmitting lens units and receiving lens units to transmit the detection light and the echo light. When different lens units are used to transmit the detection light and the echo light, the detection light and the echo light are not transmitted through the same lens unit. In this way, the aberration of the transmitting lens unit and the receiving lens unit can be improved, which is convenient for mass production. Furthermore, the area requirement for the two-dimensional array detector can be reduced, which is beneficial to reducing costs.

[0040] In an optional solution disclosed herein, the focal length of the receiving lens is no greater than the focal length of the transmitting lens of the transmitting lens unit. Transmitting lenses with larger focal lengths are compatible with lasers with larger luminous areas. Receiving lenses with smaller focal lengths are compatible with detectors with smaller photosensitive areas. While matching the transmitting and receiving fields of view, a transmitting lens with a larger focal length and a receiving lens with a smaller focal length are suitable for lasers with larger luminous areas and detectors with smaller photosensitive areas. This facilitates the improvement of LiDAR range-finding capabilities.

[0041] In an optional solution disclosed herein, the size of the pixels in the two-dimensional array detector is greater than the optical parameters of the receiving lens. The optical parameters of the receiving lens may be the root mean square spot radius of the receiving lens. The relationship between the size of the pixels in the two-dimensional array detector and the optical parameters of the receiving lens may affect the point cloud quality, optical resolution, etc. obtained by the two-dimensional array detector. The size of the pixels in the two-dimensional array detector and the optical parameters of the receiving lens may be matched to each other. In this way, the optical resolution of the lidar may be improved, which is conducive to obtaining optimal imaging quality and improving the point cloud quality of the lidar.

[0042] In an optional embodiment of the present disclosure, the receiving lens has a receiving aperture greater than 8 mm. A larger receiving aperture increases the laser radar's efficiency in receiving echo light and enhances its range-finding capability. A sufficiently large receiving aperture can improve both the laser radar's efficiency in receiving echo light and its range-finding capability.

[0043] In an optional solution disclosed herein, the receiving lens has an F-number less than 4. The F-number of a lens, such as the aperture coefficient of a lens, is the ratio of the lens' focal length to the clear aperture. The luminous flux of a lens is inversely proportional to the square of the F-number; the smaller the F-number, the greater the luminous flux. The smaller the F-number of the receiving lens, the larger the receiving aperture of the receiving lens, and the higher the efficiency of receiving the echo light. A sufficiently small F-number of the receiving lens is conducive to improving the efficiency of receiving the echo light.

[0044] In an optional solution disclosed herein, the laser of the transmitting unit and the two-dimensional array detector of the receiving unit are arranged on the same circuit board. The laser of the transmitting unit and the two-dimensional array detector of the receiving unit are integrated on the same board, which is conducive to the mass production of laser radar.

[0045] In an optional solution disclosed herein, the two-dimensional array detector further comprises a compensation region, the compensation region surrounding the plurality of detection regions. The two-dimensional array detector can be driven in an addressable manner. The two-dimensional array detector achieves alignment of the transmitting field of view and the receiving field of view through addressing drive. Utilizing the compensation region to compensate for errors in alignment between the transmitting field of view and the receiving field of view can reduce the difficulty of optical alignment and adjustment. In some embodiments, the optical alignment and adjustment process can be avoided, which is conducive to achieving alignment-free alignment of lasers and detectors integrated on a common board.

[0046] In an optional solution disclosed herein, the beam splitting unit includes a polarization beam splitter and a wave plate, with the wave plate positioned in the optical path between the polarization beam splitter and the scanning module. This polarization-based beam splitting scheme effectively improves transmission efficiency within the volume constraints of the LiDAR, contributing to improved LiDAR performance.

[0047] In the optional solution disclosed herein, the wave plate is attached to the surface of the polarization spectrometer element facing the scanning module. By directly attaching the wave plate to the surface of the polarization spectrometer element, there is no need to set an anti-reflection film on the attached surfaces of the wave plate and the polarization spectrometer element, which is conducive to effectively reducing the coating cost. Moreover, the wave plate and the polarization spectrometer element are fixedly connected, which is conducive to effectively reducing the positioning surface, reducing the complexity and cost of mechanical design, and also helping to reduce the number of assembly components and reduce production costs. In addition, the polarization spectrometer element is a flat plate structure, which is lower in cost than the polarization spectrometer element with a prism structure, which is conducive to further reducing the cost of the laser radar.

[0048] In an optional solution disclosed herein, the scanning module includes a polygonal mirror, which includes multiple reflective surfaces, each of which rotates about a rotation axis. Different reflective surfaces have the same angle with the rotation axis. This allows adjustment of different field of view directions, expanding the vertical field of view of the laser radar without increasing the difficulty of lens design, eliminating the need to increase the lens aperture, and reducing costs. Furthermore, it helps reduce the size of the circuit board on which the laser and two-dimensional array detector are mounted, effectively reducing the height of the laser radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] To more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings used in the description of the embodiments. It should be noted that the drawings described below are merely examples, used to provide a further understanding of the present disclosure, and do not constitute a limitation of the present disclosure.

[0050] FIG1 illustrates a functional block diagram of an exemplary lidar consistent with some embodiments of the present disclosure.

[0051] FIG2 illustrates the structure of a transmitting unit of an exemplary laser radar consistent with some embodiments of the present disclosure.

[0052] FIG3 illustrates an optical path structure of an exemplary lidar consistent with some embodiments of the present disclosure.

[0053] FIG4 illustrates the field of view of an exemplary lidar consistent with some embodiments of the present disclosure.

[0054] FIG5 illustrates a functional block diagram of another exemplary lidar consistent with some embodiments of the present disclosure.

[0055] FIG6 illustrates another exemplary optical path structure of a laser radar consistent with some embodiments of the present disclosure.

[0056] FIG7 illustrates the structure of a transmitting unit of another exemplary laser radar consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0057] In the present disclosure, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the present disclosure. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present disclosure, "multiple" means two or more, unless otherwise expressly defined.

[0058] In the present disclosure, the terms "or" and "and / or" describe the association relationship between related objects and represent a non-exclusive inclusion. For example, "A and / or B" and "A or B" may include: only "A" exists, only "B" exists, and "A" and "B" exist at the same time, where "A" and "B" can be singular or plural. For another example, "A, B and / or C" and "A, B or C" may include: only "A" exists, only "B" exists, only "C" exists, "A" and "B" exist at the same time, "A" and "C" exist at the same time, "B" and "C" exist at the same time, and "A", "B" and "C" exist at the same time, where "A", "B" and "C" can be singular or plural. In addition, the symbol " / " in the present disclosure indicates that there is an "or" relationship between the related objects before and after the symbol. In the present disclosure, the term "at least one A or B" has the same meaning as the above-mentioned "A or B". The term "at least one A, B or C" has the same meaning as the above-mentioned "A, B or C".

[0059] In the description of the present disclosure, in some embodiments, unless otherwise explicitly described, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection, an electrical connection, or a communicative connection. It can be a direct connection, an indirect connection achieved through an intermediate medium, or a connection within an element or an interaction between elements.

[0060] In the present disclosure, unless otherwise explicitly described, a description of a first feature being "on" or "below" a second feature may include the first feature and the second feature being in direct contact or indirect contact (for example, contact through another feature between them). Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0061] The present disclosure provides many different embodiments for implementing different structures of the present disclosure. To simplify the description, the components and settings of specific examples are described below. It should be noted that they are merely examples and are not intended to limit the present disclosure. In addition, the present disclosure may repeat reference numerals, reference letters, or reference numerals and reference letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments or settings discussed. In addition, the present disclosure provides examples of various specific processes and materials, but these examples are merely examples and do not constitute a limitation of the present disclosure.

[0062] The present disclosure provides a laser radar including an optical transceiver module and a scanning module. In some embodiments, the optical transceiver module may include a transmitting unit, a transmitting lens unit, a receiving lens unit, and a receiving unit. The transmitting unit may generate detection light. The transmitting lens unit may transmit the detection light. The receiving lens unit may be separated from the transmitting lens unit. The receiving lens unit may transmit echo light formed by reflection of the detection light from an object. In some embodiments, the receiving unit may include a two-dimensional array detector. The two-dimensional array detector may detect the echo light passing through the receiving lens unit. The scanning module may receive the detection light and emit it to the outside of the laser radar, and receive the echo light and emit it to the optical transceiver module.

[0063] In some embodiments, the receiving unit can use a two-dimensional array detector to receive the echo light. Doing so can effectively reduce the receiving field of view corresponding to each detector in the laser radar, improve the optical resolution of the laser radar optical system, and thus enhance the laser radar's ability to distinguish targets. In some embodiments, for the two-dimensional array detector, the optical transceiver module can use a separate transmitting lens unit and receiving lens unit. The transmitting lens unit can transmit the detection light. The receiving lens unit can transmit the echo light. By using different lens units to transmit the detection light and the echo light, the detection light and the echo light are not transmitted through the same lens unit, thereby improving the aberration of the transmitting lens unit and the receiving lens unit, facilitating mass production, and reducing the area of ​​the two-dimensional array detector and reducing costs.

[0064] FIG1 illustrates a functional block diagram of an exemplary lidar consistent with some embodiments of the present disclosure.

[0065] In FIG1 , the laser radar includes, by way of example, an optical transceiver module 101 and a scanning module 102. The optical transceiver module 101 includes a transmitting unit 110, a transmitting lens unit 120, a receiving lens unit 130, and a receiving unit 140. The transmitting unit 110 can generate probe light 119. The transmitting lens unit 120 can transmit the probe light 119. The receiving lens unit 130 is separate from the transmitting lens unit 120. The receiving lens unit 130 can transmit the echo light 149 formed by the reflection of the probe light 119 from an object. The receiving unit 140 includes a two-dimensional array detector 141. The two-dimensional array detector 141 can detect the echo light 149 that passes through the receiving lens unit 130. The scanning module 102 can receive the probe light 119 emitted to the exterior of the laser radar and receive the echo light 149 emitted toward the optical transceiver module 101.

[0066] In some embodiments, the receiving unit uses a two-dimensional array detector 141 to receive the echo light 149. This reduces the receiving field of view corresponding to each detector in the laser radar, improves the optical resolution of the laser radar optical system, and thus enhances the laser radar's ability to distinguish targets. In some embodiments, for the two-dimensional array detector 141, the optical transceiver module 101 can use separate transmitting lens units 120 and receiving lens units 130. The transmitting lens unit 120 can transmit the probe light 119. The receiving lens unit 130 can transmit the echo light 149. By using different lens units to transmit the probe light 119 and the echo light 149, the probe light 119 and the echo light 149 are not transmitted through the same lens unit. This can improve the aberration of the transmitting lens unit 120 and the receiving lens unit 130, facilitate mass production, and reduce the area of ​​the two-dimensional array detector 141, thereby reducing costs.

[0067] In some embodiments, the optical transceiver module 101 can transmit and receive optical signals. The transmitting unit 110 can generate detection light 119 .

[0068] In some embodiments, the emitting unit 110 may include multiple light sources 111. Each light source 111 may generate a beam of probe light 119. The light source 111 may be a laser. For example, the laser may be a vertical-cavity surface-emitting laser (VCSEL), an edge-emitting laser (EEL), or other light-emitting device that generates laser light. The wavelength of the laser emitted by the laser may be any one of 905 nanometers (nm), 940 nm, and 1550 nm, or may emit laser light of other wavelengths.

[0069] In some embodiments, the multiple light sources 111 of the emission unit 110 may be VCSELs. The detection light 119 generated by the VCSELs may be polarized light (eg, P-polarized light).

[0070] FIG2 shows the structure of the transmitting unit of an exemplary laser radar consistent with some embodiments of the present disclosure. In FIG2 , illustratively, the multiple light sources 111 of the transmitting unit 110 can be arranged in an array. For example, the light sources 111 of adjacent columns can be staggered along the column direction. For another example, the light sources 111 of adjacent rows can be staggered along the row direction. In FIG2 , illustratively, the transmitting unit 110 includes two columns of light sources 111. In some embodiments, the transmitting unit 110 can have light sources of other numbers of columns (for example, 3 columns, 4 columns, etc.). The present disclosure does not limit the number of columns of the multiple light sources arranged in an array in the transmitting unit.

[0071] In some embodiments, in the array of multiple light sources 111, the column direction may correspond to the vertical field of view of the laser radar. The column direction may correspond to the direction perpendicular to the horizontal plane. The row direction may correspond to the horizontal field of view of the laser radar. The row direction may correspond to the direction parallel to the horizontal plane.

[0072] The transmitting lens unit 120 can transmit the detection light 119 to collimate and adjust the optical path.

[0073] Continuing with reference to FIG1 , in some embodiments, the emission lens unit 120 includes a reflector 121 and an emission lens 122. The emission lens 122 includes at least one emission lens. The reflector 121 of the emission lens unit 120 can reflect the detection light 119 toward the scanning module 102. The reflector 121 can change the optical path of the detection light 119. The emission lens 122 can collimate the detection light 119. For example, the emission lens 122 can include multiple emission lenses (e.g., spherical lenses or aspherical lenses), and the optical axes of the multiple emission lenses can overlap.

[0074] 1 and 2 , illustratively, the number of emission lenses in the emission lens 122 is in the range of 2 to 6. In some embodiments, a reflector 121 may be provided in the optical path between two emission lenses in the plurality of emission lenses.

[0075] In some embodiments, the optical transceiver module 101 includes a support member 160. At least the transmitting lens unit 120 is fixed to the support member 160. The support member 160 can support and position optical components. In some embodiments, the support member 160 is a single mechanical component. Using a single mechanical component to support optical components facilitates mass production.

[0076] 1 , illustratively, the transmitting lens unit 120 is fixed to the support 160 . In some embodiments, all the transmitting lenses and the reflector 121 in the transmitting lens 122 are fixedly connected to the support 160 .

[0077] FIG3 illustrates an optical path structure of an exemplary laser radar consistent with some embodiments of the present disclosure. Referring to FIG1 and FIG3 , illustratively, the optical transceiver module 101 includes a spectrometer 170. The spectrometer 170 can transmit the detection light 119 transmitted by the transmitting lens unit 120 to the scanning module 102. The spectrometer 170 can also transmit the echo light 149 transmitted by the scanning module 102 to the receiving lens unit 130. The spectrometer 170 can separate the optical path of the detection light 119 from the optical path of the echo light 149. In some embodiments, the spectrometer 170 includes a polarization spectrometer 172 and a wave plate 171. The wave plate 171 is located in the optical path between the polarization spectrometer 172 and the scanning module 102. For example, the polarization spectrometer 172 can be a polarization spectrometer. The wave plate 171 can be a quarter-wave plate. Using the polarization principle to achieve spectrometering can achieve higher transmission efficiency within the volume constraints of the laser radar, thereby ensuring the laser radar's range finding capability. Moreover, compared with the polarization beam splitter element with a prism structure, the polarization beam splitter element with a flat plate structure has lower cost, which can further control the cost.

[0078] Referring to Figure 3 , illustratively, the wave plate 171 is attached to the surface of the polarization beam splitter element 172 facing the scanning module 102. Directly attaching the wave plate 171 to the surface of the polarization beam splitter element 172 can effectively reduce the number of separate components in the lidar. When the wave plate 171 is directly attached to the surface of the polarization beam splitter element 172, the attaching surfaces of the wave plate 171 and the polarization beam splitter element 172 do not need to be coated with an anti-reflection film, which can reduce coating costs. The wave plate 171 and the polarization beam splitter element 172 are fixedly connected, which can reduce positioning surfaces, reduce mechanical design complexity and mechanical component costs, and also reduce the number of assembly components and production costs.

[0079] In some embodiments, the probe light incident on the polarization beam splitter 172 can be linearly polarized light (e.g., P-polarized light). For example, linearly polarized light can be directly generated by a VCSEL. Another example is that linearly polarized light can be generated using a polarizer. The polarization beam splitter 172 can convert the incident linearly polarized light into circularly polarized light for output. After transmitting through the wave plate 171, the circularly polarized probe light 119 can be emitted from the beam splitter unit 170.

[0080] Continuing with reference to FIG1 , illustratively, the transmitting lens unit 120 is fixed to the support 160. The spectrometer unit 170 is also fixed to the support 160. Both the transmitting lens unit 120 and the spectrometer unit 170 are fixed to the support. All the transmitting lenses and reflectors 121 in the transmitting lens 122, as well as the polarization spectrometer element 172 and wave plate 172 in the spectrometer unit 170, are fixedly connected to the support 160.

[0081] Continuing with FIG1 , illustratively, scanning module 102 can change the emission direction of probe light 119 to form a scanning field of view. Scanning module 102 can reflect probe light 119 outside the laser radar. Scanning module 102 can also reflect return light 149 to optical transceiver module 101.

[0082] Continuing with reference to FIG1 , the scanning module 102 can be, for example, a one-dimensional scanning module. For example, in FIG3 , the scanning module 102 includes a unidirectional rotating mirror (or simply referred to as a "rotating mirror"). In some embodiments, the scanning module 102 can also include a galvanometer mirror, which includes a micro-electro-mechanical system (MEMS) mirror or a galvanometer (Galvo) mirror.

[0083] In some embodiments, the scanning module 102 includes a polygonal mirror 102a. The polygonal mirror may include multiple reflective surfaces 102b. In some embodiments, each of the multiple reflective surfaces 102b is rotatable about a rotation axis 102c. In some embodiments, the angles between different reflective surfaces 102b and the rotation axis 102c are partially the same. For example, the angle between at least one reflective surface 102b and the rotation axis 102c is different from the angles between the other reflective surfaces 102b and the rotation axis 102c.

[0084] Continuing with FIG3 , polygon mirror 102a is illustratively a four-sided mirror. Polygon mirror 102a has four reflecting surfaces 102b. The four reflecting surfaces 102b have the same angle with the rotation axis 102c. Of the four reflecting surfaces 102b, at least one reflecting surface 102b has a different angle with the rotation axis 102c than the other reflecting surfaces 102b.

[0085] In some embodiments, the polygonal mirror has an even number of reflective surfaces. In some embodiments, adjacent reflective surfaces have different angles with the rotation axis, while alternate reflective surfaces have the same angle with the rotation axis. Continuing with FIG3 , for example, in the four mirrors 102a of the scanning module 102, the angles of the four reflective surfaces 102b with the rotation axis 102c are +1°, -1°, +1°, and -1°, respectively.

[0086] In some embodiments, the positive or negative value of the angle between the reflective surface 102b and the rotation axis 102c may indicate that the directions of the angles formed between the reflective surface 102b and the rotation axis 102c are different. For example, the reflective surface 102b and the rotation axis 102c, both of which have an angle of +1°, have the same angle direction. For another example, the angle formed between the reflective surface 102b and the rotation axis 102c, when the angle is +1°, is opposite to the angle formed between the reflective surface 102b and the rotation axis 102c, when the angle is -1°.

[0087] Continuing with reference to FIG3 , illustratively, the detection light 119 can be scanned in the horizontal direction by the scanning module 102 to form a horizontal field of view of the laser radar. The rotation axis 102c of the polygonal mirror 102a intersects the horizontal plane (for example, the two are perpendicular). In some embodiments, the vertical field of view of the detection light 119 transmitted by the spectrometer 170 can range from -11° to +11°. In some embodiments, the vertical field of view formed by the detection light 119 emitted after reflection from the scanning module 102 can range from -13° to +13°.

[0088] FIG4 shows the field of view of an exemplary laser radar consistent with some embodiments of the present disclosure. Referring to FIG4 , illustratively, the vertical field of view formed by the emitted detection light 119 (e.g., representing the vertical field of view of the laser radar) includes a central area 105c and edge areas 105m located on both sides of the central area 105c. In some embodiments, the vertical field of view corresponding to the central area 105c may range from -9° to +9°. In some embodiments, the edge areas 105m may be -13° to -9° and +9° to +13°, respectively. In some embodiments, the detection light 119 reflected by all reflecting surfaces 102b may cover the central area 105c. In some embodiments, the detection light 119 reflected by adjacent reflecting surfaces 102b may cover different edge areas 105m. For example, the detection light 119 reflected by one reflecting surface 102b may cover the edge area 105m on the upper side. For another example, the detection light 119 reflected by adjacent reflecting surfaces 102b may cover the edge area 105m on the lower side. In some embodiments, the frame rate of the central region 105c is higher, and the frame rate of the edge region 105m is lower. In some embodiments, the central region 105c is a high frame rate region, and the edge region 105m is a low frame rate region.

[0089] In some embodiments, by designing the angles between the different reflective surfaces 102b and the rotation axis 102c of the polygon mirror 102a in the scanning module 102, different field of view directions can be adjusted. This expands the field of view without increasing the difficulty of lens design or the need to increase the lens diameter. Furthermore, this solution can reduce costs and the height of the LiDAR.

[0090] 1 and FIG3 , illustratively, the scanning module 102 can be located in the optical path between the spectroscopic unit 170 and the space outside the laser radar. In some embodiments, the scanning module 102 can receive the probe light 119 transmitted by the spectroscopic unit 170 and reflect the received probe light 119 back to the space outside the laser radar. In some embodiments, the scanning module 102 can also receive the echo light 149 formed by the reflection of the probe light 119 from an object in the external space and reflect the received echo light 149 back to the spectroscopic unit 170. The spectroscopic unit 170 can further transmit the echo light 149 to the receiving lens unit 130.

[0091] In some embodiments, circularly polarized probe light 119 transmitted through spectrometer 170 may be reflected by scanning module 102 to the exterior of the laser radar, where it is reflected by an object to form return light 149. Without considering the effects of depolarization during transmission outside the laser radar, the polarization state of return light 149 is substantially the same as that of probe light 119, and return light 149 may also be circularly polarized.

[0092] In some embodiments, the scanning module 102 may reflect the received echo light 149 to the spectrometer 170 . The echo light 149 incident on the spectrometer 170 may be incident on the polarization spectrometer 172 after being transmitted through the wave plate 171 .

[0093] In some embodiments, during light beam transmission, the probe light 119, after emitting from the polarization beam splitter 172, can be transmitted through the wave plate 171 to the scanning module 102. In some embodiments, the return light 149 can be transmitted through the wave plate 171 and then incident on the polarization beam splitter 172. After being reflected by the polarization beam splitter 172, the return light 149 can be transmitted again through the wave plate 171. In this case, the return light can be transmitted through the wave plate 171 twice. When the wave plate 171 is a quarter-wave plate, the phase of the return light 149 emitted from the beam splitter 170 can be shifted by π / 2 compared to the probe light 119 emitted from the polarization beam splitter 172 and the return light 149 incident on the beam splitter 170. In this case, the return light can still be circularly polarized. In some embodiments, the polarization beam splitter 172 can transmit the incident return light 149 toward the receiving lens unit 130, thereby separating the optical paths of the probe light 119 and the return light 149.

[0094] In some embodiments, the receiving lens unit 130 is separated from the transmitting lens unit 120 and can be located downstream of the light splitting unit 170 in the optical path of the return light 149. The receiving lens unit 130 can converge the return light 149 to the receiving unit 140.

[0095] In some embodiments, the receiving lens unit 130 may include a receiving lens 131. The receiving lens 131 may include at least one receiving lens. With continued reference to FIG1 and FIG3 , illustratively, the optical path in the receiving lens unit 130 does not change. For example, the receiving lens unit 130 does not include a reflector.

[0096] In some embodiments, the receiving lens 131 can converge the echo light 149 transmitted by the spectrometer 170 to the receiving unit 140. For example, the receiving lens 131 can include multiple receiving lenses. The receiving lenses can be spherical lenses or aspherical lenses. The optical axes of the multiple receiving lenses can overlap. Continuing with FIG. 1 , illustratively, the number of receiving lenses in the receiving lens 131 ranges from 2 to 6.

[0097] In some embodiments, the focal length of the receiving lens 131 may not be greater than the focal length of the transmitting lens 122 of the transmitting lens unit 120. In some embodiments, the focal length of the receiving lens 131 may be less than the focal length of the transmitting lens 122 of the transmitting lens unit 120.

[0098] The transmitting lens 122 has a larger focal length, making it compatible with the transmitting unit 110, which has a larger light-emitting area. The receiving lens 131 has a smaller focal length, making it compatible with the two-dimensional array detector 141 in the receiving unit 140, which has a smaller light-sensitive area. This ensures that the transmitting and receiving fields of view match while maintaining the laser radar's range-finding capability.

[0099] In some embodiments, the transceiver module 101 may include a transmitting component 103 and a receiving component 104. For example, the transmitting component 103 may include a transmitting unit 110 and a transmitting lens unit 120. The receiving component 104 may include a receiving lens unit 130 and a receiving unit 140. As shown in Figures 1 and 3, the receiving component 104 is illustratively located between the transmitting component 103 and the scanning module 102. Placing the receiving component 104 between the transmitting component 103 and the scanning module 102 allows for adaption to the transmitting lens 122 with a larger focal length and the receiving lens 131 with a smaller focal length, thereby optimizing the optical path configuration.

[0100] In some embodiments, the receiving aperture of the receiving lens 131 may be greater than 8 mm. In some embodiments, the larger the receiving aperture of the receiving lens 131, the stronger the range-finding capability of the laser radar. A sufficiently large receiving aperture of the receiving lens 131 allows the laser radar to obtain sufficient range-finding capability.

[0101] In some embodiments, the F number of the receiving lens 131 may be less than 4. The F number of a lens, such as the aperture coefficient of a lens, may refer to the ratio of the focal length of the lens to the clear aperture. The luminous flux of a lens is generally inversely proportional to the square of the F number. For example, the smaller the F number, the greater the luminous flux. The smaller the F number of the receiving lens 131 and the larger the receiving aperture of the receiving lens 131, the higher the efficiency of receiving the echo light 149. In some embodiments, the F number of the receiving lens 131 may be less than 1.8. Among them, the F number of the receiving lens may refer to the inverse of the relative aperture of the receiving lens (also called "aperture number"). For example, F / 5.6 means that the F number is equal to 5.6, which means that the focal length of the lens is equal to 5.6 times the aperture diameter. The light intensity received by the image plane is generally inversely proportional to the square of the F number. The F number is also called the lens speed. Lenses with a small F number are generally fast.

[0102] In some embodiments, the focal length of the receiving lens 131 can be determined based on the spacing between adjacent pixels in the two-dimensional array detector 141 and the angular resolution of the laser radar. For example, if the spacing between adjacent pixels in the two-dimensional array detector 141 is Δd and the angular resolution of the laser radar is Δθ, then the focal length f of the receiving lens 131 is:

[0103] In some embodiments, the optical transceiver module 101 may further include a support 160. The receiving lens unit 130, the transmitting lens unit 120, and the spectrometer unit 170 may all be fixed to the support 160. In this way, the optical components of the laser radar do not need to be adjusted, thereby reducing the difficulty of adjusting the laser radar.

[0104] Continuing with reference to Figures 1 and 3, illustratively, the receiving unit 140 includes a two-dimensional array detector 141. The two-dimensional array detector 141 is located in the optical path of the return light 149 downstream of the receiving lens unit 130. The two-dimensional array detector 141 can detect the return light 149 that has passed through the receiving lens unit 130. For example, the two-dimensional array detector 141 includes a plurality of detection elements arranged in a two-dimensional array. The detection elements can be single-photon detection elements. For example, the single-photon detection elements can be single-photon avalanche diodes (SPADs).

[0105] In some embodiments, unlike a plurality of individually packaged detectors arranged in a two-dimensional manner, the plurality of detection elements in the two-dimensional array detector 141 can be driven in an addressable manner, thereby reducing the distance between adjacent detection elements.

[0106] In some embodiments, the multiple detection elements of the two-dimensional array detector 141 can be arranged along two intersecting directions. For example, one direction can correspond to the vertical field of view of the laser radar, corresponding to a direction perpendicular to the horizontal plane. The other direction can correspond to the horizontal field of view of the laser radar, corresponding to a direction parallel to the horizontal plane.

[0107] In some embodiments, the two-dimensional array detector 141 may include multiple pixels. One pixel may include multiple detection elements. For example, at least one pixel may include multiple detection elements. For another example, each pixel may include multiple detection elements. In some embodiments, the detection element may be a single-photon detection element. One pixel of the two-dimensional array detector 141 may include multiple detection elements. For example, each pixel may include 4 single-photon avalanche diodes. Each pixel (for example, 4 SPADs) may output 1 signal for subsequent circuit sampling and processing. The number of detection elements contained in different pixels may be the same or different.

[0108] In some embodiments, the pixel size of the two-dimensional array detector 141 can be larger than the optical parameters of the receiving lens 131. In some embodiments, the optical parameters can be image quality design parameters. For example, the optical parameters can be the root mean square (RMS) spot radius (e.g., RMS radius). Typically, the RMS spot radius is the spot radius obtained by taking the square root of the quadratic average of the light intensity distribution and is a metric that can describe the size of a light beam.

[0109] In some embodiments, the RMS spot radius of a lens can affect the optical resolution of the point cloud captured by the detector. A smaller RMS spot radius indicates better optical performance, resulting in a sharper point cloud and higher resolution. Pixel size is a parameter of a two-dimensional array detector; smaller pixels allow for greater detail to be captured.

[0110] In order to obtain more point cloud details, in addition to applying a smaller detector pixel size, it can also be achieved through better lens performance. If the pixel size is much smaller than the rms spot radius of the lens, the potential resolution may be wasted.

[0111] The best point cloud quality can be achieved by combining appropriate lens optical parameters with an appropriate pixel size. When the lens's root mean square spot radius is less than or equal to the pixel size, the point cloud resolution can be improved.

[0112] In some embodiments, a pixel of the two-dimensional array detector 141 may include multiple detection elements. For example, each pixel includes 2×2 or 3×3 SPADs. The size of each pixel of the two-dimensional array detector 141 is larger than the root mean square radius of the receiving lens 131.

[0113] 2 , in some embodiments, the receiving unit 140 includes a two-dimensional array detector 141. The two-dimensional array detector 141 includes multiple detection zones 141 t. The multiple detection zones 141 t correspond to the multiple lasers 111 of the transmitting unit 110, for example, in a one-to-one, many-to-one, or one-to-many relationship.

[0114] The receiving unit 140 adopts an addressable two-dimensional array detector. Each laser of the transmitting unit 110 can correspond to one detection area 141t of the two-dimensional array detector 141 in the receiving unit 140. The detection area 141t may include at least one pixel. For example, at least one detection area 141 (e.g., each detection area 141) may include m×n pixels. At least one pixel (e.g., each pixel) may generate p point clouds. In the point cloud of the laser radar, the number of points in the vertical field of view may be n×p. In this way, the vertical field of view can be encrypted, thereby improving the density and resolution of the point cloud.

[0115] In some embodiments, the light emitting area S of the laser tx and the focal length f of the transmitting lens 122 tx , the field of view of the emission field θ tx The relationship can be: tx ×θ tx =S tx In some embodiments, the photosensitive area S of the detection area 141 corresponding to the laser rx and the focal length f of the receiving lens 131 rx , the field of view of the receiving field of view θ rx The relationship can be: rx ×θ rx =S rx .

[0116] In some embodiments, when the optical power density of the laser in the transmitting unit 110 is limited, a laser with a larger light emitting area can improve the distance measurement capability of the laser radar. tx Greater than the focal length f of the receiving lens 131 rx When the transmitting and receiving fields of view are matched, the photosensitive area of ​​the detection area 141t corresponding to the laser is made smaller, thereby improving the optical resolution of the laser radar.

[0117] Continuing with reference to FIG. 2 , illustratively, the two-dimensional array detector 141 may further include a compensation region 141m. The compensation region 141m may surround multiple detection regions 141t. The two-dimensional array detector 141 may be driven in an addressable manner. This allows alignment of the transmitting field of view and the receiving field of view. In some embodiments, utilizing the compensation region 141m to compensate for errors in alignment between the transmitting field of view and the receiving field of view can reduce the difficulty of optical alignment and adjustment, and may even avoid the optical alignment and adjustment process, thereby achieving alignment-free alignment of the co-integrated laser and detector.

[0118] In some embodiments, the optical transceiver module 101 may further include a circuit board 150. For example, the laser 111 of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 may be fixed to the circuit board 150. Continuing with reference to FIG. 1 , illustratively, the laser 111 of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 may be disposed on the same circuit board 150. The laser of the transmitting unit and the two-dimensional array detector of the receiving unit may be integrated on the same board, thereby enabling mass production.

[0119] In some embodiments, the focal length f of the transmitting lens 122 is tx Can be greater than the focal length f of the receiving lens 131 rx When the focal length f of the transmitting lens 122 is tx and the focal length f of the receiving lens 131 rx When the difference is appropriate, the laser of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 can be integrated on the same board.

[0120] 1 , illustratively, the receiving unit 140 further includes a filter 142. The filter 142 may be located in the optical path between the receiving lens 131 and the two-dimensional array detector 141. The filter 142 may filter out stray light.

[0121] Figure 5 shows a functional block diagram of another exemplary laser radar consistent with some embodiments of the present disclosure. Figure 6 shows an optical path structure of another exemplary laser radar consistent with some embodiments of the present disclosure. The similarities between Figures 5 and 6 and the embodiments are not repeated here. Unlike the embodiments described in conjunction with Figures 1-4, in Figures 5 and 6, exemplarily, the transmitting lens unit 220 and the spectrometer unit 270 are both fixed to the support 260. The optical transceiver module 201 also includes a receiving lens support 261. The receiving lens 231 is fixed to the receiving lens support 261. The receiving lens support 261 is movably connected to the support 260.

[0122] 6 , illustratively, the multiple receiving lenses of the receiving lens 231 in the receiving lens unit 230 are all fixedly connected to the receiving lens support 261. The receiving lens support 261 is movably fixed to the support 260. In some embodiments, the receiving lens support 261 can be adjusted in multiple dimensions relative to the support 260, and the dimensions can include one of two to five dimensions. In some embodiments, the movable receiving lens support 261 can be used to change the distance D between the receiving lens 231 and the two-dimensional array detector 241 of the receiving unit 140 through active focusing technology (Active Alignment, AA focusing), thereby achieving back focus adjustment of the receiving lens unit 230, thereby improving the optical resolution, improving the image quality of the laser radar optical system, and improving the laser radar's ability to distinguish targets.

[0123] In some embodiments, the receiving lens support 261 can be fixed by at least one of welding and gluing. For example, after the back focus of the receiving lens unit 230 is adjusted, the receiving lens support 261 and the support member 260 can be fixedly connected by at least one of welding and gluing.

[0124] FIG7 illustrates the structure of a transmitting unit of another exemplary laser radar consistent with some embodiments of the present disclosure.

[0125] Referring to FIG. 7 , illustratively, a plurality of focus marks 262 are provided on the circuit board 250 that secures the two-dimensional array detector 241. The focus marks 262 can be aligned during back-focus adjustment. The focus marks 262 can have a high-precision pattern. In some embodiments, during back-focus adjustment, the clarity of the pattern of the focus marks 262 can be used to determine whether different field of view positions of the two-dimensional array detector 241 are at the optimal back-focal plane position. In some embodiments, the position of the focus marks 262 can represent the pixel position of the two-dimensional array detector 241. In this way, the transmitting field of view and the receiving field of view can be aligned. For example, the shape of the focus marks 262 can be a tilted double rectangle. In some embodiments, the shape of the focus marks can also be circular, square, triangular, pentagonal, hexagonal, cross-shaped, target-shaped, or any other arbitrary shape.

[0126] Continuing with FIG7 , illustratively, the receiving unit 240 may include multiple two-dimensional array detectors 241. The multiple two-dimensional array detectors 241 may correspond one-to-one with the multiple lasers 211 of the transmitting unit 210. The multiple two-dimensional array detectors 241 may constitute the receiving unit 140, thereby reducing the area of ​​a single two-dimensional array detector 241 and lowering costs.

[0127] In some embodiments, the two-dimensional array detector 141 may include multiple pixels. One of the multiple pixels may include multiple detection elements. For example, the pixel may include multiple detection elements. The detection elements included in different pixels may be the same or different. In some embodiments, the detection element may be a single-photon detection element (e.g., a single-photon detection element SPAD).

[0128] In some embodiments, multiple two-dimensional array detectors 241 can be arranged in an array. For example, the two-dimensional array detectors 241 in adjacent columns can be staggered along the column direction. For another example, the two-dimensional array detectors 241 in adjacent rows can be staggered along the row direction. Referring to FIG7 , illustratively, multiple two-dimensional array detectors 241 are arranged in an array. The two-dimensional array detectors 241 in adjacent columns can be staggered along the column direction. For example, one two-dimensional array detector in a column can be located between two two-dimensional array detectors in adjacent columns along the column direction. For example, FIG7 shows four two-dimensional array detectors 241 in the receiving unit 240, arranged in a 2×2 array. The first column 201 and the second column 202 are adjacent along the row direction. The two-dimensional array detector 241 in the first column 201 is located between two adjacent two-dimensional array detectors 241 in the second column 202 along the column direction.

[0129] In some embodiments, adjacent two-dimensional array detectors 241 along the staggered direction may have overlapping regions. For example, referring again to FIG7 , the two-dimensional array detectors 241 in the first column 201 and the two-dimensional array detectors 241 in the second column 202, which are adjacent along the column direction, have overlapping regions in the column direction (as indicated by the dashed line in FIG7 ). The projections of the two-dimensional array detectors 241 in the first column 201 and the two-dimensional array detectors 241 in the second column 202 on a vertical plane have overlapping regions. The vertical plane is a plane perpendicular to the direction from the first column 201 to the second column 202.

[0130] In some embodiments, adjacent two-dimensional array detectors along the staggered direction may be completely staggered, with no overlapping regions between adjacent two-dimensional array detectors along the staggered direction. For example, the two-dimensional array detectors 241 in the first column 201 and the two-dimensional array detectors 241 in the second column 202 adjacent along the column direction are completely staggered in the column direction, with no overlapping regions.

[0131] In some embodiments, the optical transceiver module may include a transmitting lens unit and a receiving lens unit. The transmitting lens unit may transmit the detection light and collimate the detection light. The receiving lens unit may be separated from the transmitting lens unit. The receiving lens unit may transmit the echo light formed by the detection light reflected by the object. By separately setting the transmitting lens unit and the receiving lens unit to transmit the detection light and the echo light respectively, the design of the transmitting lens unit only needs to meet the technical requirements for the collimation of the detection light, thereby improving the collimation effect of the transmitting lens unit on the detection light. The design of the receiving lens unit only needs to meet the technical requirements for the reception of the echo light, thereby improving the reception effect of the receiving lens unit on the echo light. The improvement of the collimation effect of the detection light and the improvement of the reception effect of the echo light can improve the detection performance of the laser radar.

[0132] In some embodiments, the receiving unit can use a two-dimensional array detector to receive the echo light. In this way, the receiving field of view corresponding to each detector in the laser radar can be reduced, thereby improving the optical resolution of the laser radar optical system and the laser radar's ability to distinguish targets. For two-dimensional array detectors, the optical transceiver module can use separate transmitting lens units and receiving lens units to transmit the detection light and echo light respectively. When different lens units are used to transmit the detection light and echo light respectively, the detection light and echo light are not transmitted through the same lens unit, thereby improving the aberration of the transmitting lens unit and the receiving lens unit, facilitating mass production, and reducing the area requirement for the two-dimensional array detector and reducing costs.

[0133] In some embodiments, the focal length of the receiving lens may be no greater than the focal length of the transmitting lens of the transmitting lens unit. Transmitting lenses with larger focal lengths can be compatible with lasers with larger light-emitting areas. Receiving lenses with smaller focal lengths can be compatible with detectors with smaller photosensitive areas. By using a transmitting lens with a larger focal length and a receiving lens with a smaller focal length, it is possible to match the transmitting and receiving fields of view while utilizing lasers with larger light-emitting areas and detectors with smaller photosensitive areas, thereby providing lidar range-finding capabilities.

[0134] In some embodiments, the pixel size of a two-dimensional array detector can be larger than the optical parameters of a receiving lens. The optical parameters of a receiving lens can be the root mean square (RMS) spot radius of the receiving lens. The relationship between the pixel size of a two-dimensional array detector and the optical parameters of a receiving lens can affect the quality of the point cloud and optical resolution obtained by the two-dimensional array detector. Matching the pixel size of a two-dimensional array detector with the optical parameters of a receiving lens can improve the optical resolution of the LiDAR, achieve better imaging quality, and enhance the quality of the LiDAR point cloud.

[0135] In some embodiments, the receiving aperture of the receiving lens can be larger than 8 mm. In some embodiments, a larger receiving aperture of the receiving lens increases the laser radar's efficiency in receiving echo light and enhances the laser radar's range-finding capability. A sufficiently large receiving aperture of the receiving lens can improve the laser radar's range-finding capability while increasing the efficiency of echo light reception.

[0136] In some embodiments, the F-number of the receiving lens can be less than 4. The F-number of a lens, such as the aperture coefficient of a lens, can be the ratio of the lens focal length to the clear aperture. The luminous flux of a lens can be inversely proportional to the square of the F-number. The smaller the F-number, the greater the luminous flux. The smaller the F-number of the receiving lens, the larger the receiving aperture of the receiving lens can be, and the higher the efficiency of receiving the echo light. A sufficiently small F-number of the receiving lens can improve the efficiency of receiving the echo light.

[0137] In some embodiments, the laser of the transmitting unit and the two-dimensional array detector of the receiving unit can be provided on the same circuit board. The laser of the transmitting unit and the two-dimensional array detector of the receiving unit can be integrated on the same board, which is conducive to the mass production of lidar.

[0138] In some embodiments, the two-dimensional array detector may further include a compensation region. The compensation region may surround multiple detection regions. The two-dimensional array detector may be driven in an addressable manner. Addressable driving enables alignment of the transmitting and receiving fields of view. Using the compensation region to compensate for errors in alignment between the transmitting and receiving fields of view can reduce the difficulty of optical alignment and can even eliminate the need for optical alignment, thereby achieving alignment-free alignment of co-integrated lasers and detectors.

[0139] In some embodiments, the beam splitting unit may include a polarization beam splitter and a wave plate. The wave plate may be located in the optical path between the polarization beam splitter and the scanning module. Using polarization to split beams effectively improves transmission efficiency and performance within the volume constraints of the LiDAR.

[0140] In some embodiments, the wave plate can be attached to the surface of the polarization beam splitter element facing the scanning module. By directly attaching the wave plate to the surface of the polarization beam splitter element, the surfaces of the wave plate and the polarization beam splitter element that are attached to each other do not need to be provided with an anti-reflection film, thereby reducing the coating cost. The wave plate and the polarization beam splitter element can be fixedly connected, thereby reducing the positioning surface, reducing the complexity and cost of the mechanical design, and reducing the number of assembly components and production costs. In addition, the polarization beam splitter element can be a flat plate structure. Compared with the polarization beam splitter element with a prism structure, this solution is less expensive and can further reduce the cost of the lidar.

[0141] In some embodiments, the scanning module may include a polygonal mirror. The polygonal mirror may include multiple reflective surfaces. The multiple reflective surfaces may all rotate around a rotation axis. The angles between different reflective surfaces and the rotation axis may be partially the same. When the angles between different reflective surfaces and the rotation axis are partially the same, the directions of different fields of view can be adjusted, thereby expanding the vertical field of view of the laser radar. At the same time, this solution does not increase the difficulty of lens design and does not require an increase in lens aperture, thereby reducing costs. Furthermore, this solution can also reduce the size of the circuit board on which the laser and two-dimensional array detector are mounted, thereby reducing the height of the laser radar.

[0142] Although the present disclosure is disclosed above, the present disclosure is not limited to the above-described embodiments. The present disclosure has different focuses on the description of each embodiment, but for parts that are not described or recorded in detail in a particular embodiment, reference can be made to the relevant descriptions of other embodiments. In addition, the embodiments described in the present disclosure can be freely combined as needed.

Claims

1. A laser radar, characterized in that: include: Optical transceiver module and scanning module; The optical transceiver module comprises: a transmitting unit configured to generate detection light; a transmitting lens unit, wherein the transmitting lens unit is configured to transmit the detection light; A receiving lens unit, the receiving lens unit is separated from the transmitting lens unit, and the receiving lens unit is configured to transmit the echo light formed by the detection light being reflected by the object; A receiving unit, the receiving unit comprising: a two-dimensional array detector, the two-dimensional array detector being configured to detect the echo light passing through the receiving lens unit; The scanning module is configured to receive the detection light emitted to the outside of the laser radar, and receive the echo light emitted to the optical transceiver module.

2. The laser radar according to claim 1, characterized in that The transmitting lens unit includes a reflector and a transmitting lens, the transmitting lens includes at least one transmitting lens, and the reflector is configured to reflect the detection light toward the scanning module.

3. The laser radar according to claim 1 or 2, characterized in that: The receiving lens unit includes a receiving lens, and the receiving lens includes at least one receiving lens.

4. The laser radar according to claim 3, characterized in that: The focal length of the receiving lens is determined according to the interval between adjacent pixels in the two-dimensional array detector and the angular resolution of the laser radar.

5. The laser radar according to claim 4, characterized in that The focal length of the receiving lens is not greater than the focal length of the transmitting lens of the transmitting lens unit.

6. The laser radar according to claim 5, characterized in that The receiving component is located between the transmitting component and the scanning module, wherein the transmitting component includes: the transmitting unit and the transmitting lens unit, and the receiving component includes: the receiving unit and the receiving lens unit.

7. The laser radar according to claim 3, characterized in that: The size of pixels in the two-dimensional array detector is greater than the optical parameters of the receiving lens.

8. The laser radar according to claim 3, characterized in that: The receiving aperture of the receiving lens is greater than 8 mm.

9. The laser radar according to claim 3, characterized in that: The F number of the receiving lens is less than 4.

10. The laser radar according to any one of claims 1 to 3, characterized in that: The laser of the transmitting unit and the two-dimensional array detector of the receiving unit are arranged on the same circuit board.

11. The laser radar according to any one of claims 1 to 10, characterized in that: The optical transceiver module further includes: a support member, and at least the transmitting lens unit is fixed to the support member.

12. The laser radar according to claim 11, characterized in that: The transmitting lens unit and the light splitting unit are both fixed to the supporting member.

13. The laser radar according to claim 11 or 12, characterized in that: The optical transceiver module further includes: a receiving lens support, the receiving lens is fixed to the receiving lens support, and the receiving lens support is movably connected to the support.

14. The laser radar according to any one of claims 1 to 13, characterized in that: A plurality of focusing marks are arranged on a circuit board for fixing the two-dimensional array detector.

15. The laser radar according to claim 11, characterized in that: The receiving lens unit, the transmitting lens unit and the light splitting unit are all fixed to the supporting member.

16. The laser radar according to any one of claims 1 to 15, characterized in that: The receiving unit includes a two-dimensional array detector, and the two-dimensional array detector includes: a plurality of detection areas, and the plurality of detection areas correspond one-to-one to the plurality of lasers of the transmitting unit.

17. The laser radar according to claim 16, characterized in that: The two-dimensional array detector further includes a compensation area, wherein the compensation area surrounds the plurality of detection areas.

18. The laser radar according to any one of claims 1 to 17, characterized in that: The receiving unit includes a plurality of two-dimensional array detectors, and the plurality of two-dimensional array detectors correspond to the plurality of lasers of the transmitting unit.

19. The laser radar according to claim 18, characterized in that: The plurality of two-dimensional array detectors are arranged in an array; the two-dimensional array detectors in adjacent columns are staggered along the column direction or the two-dimensional array detectors in adjacent rows are staggered along the row direction.

20. The laser radar according to any one of claims 1 to 19, characterized in that: The two-dimensional array detector includes a plurality of pixels, and at least one pixel of the plurality of pixels includes a plurality of detection elements.

21. The laser radar according to claim 20, characterized in that The detection element is a single-photon detection element.

22. The laser radar according to any one of claims 1 to 20, characterized in that: The optical transceiver module further includes: a spectroscopic unit, which is configured to transmit the detection light transmitted by the transmitting lens unit to the scanning module, and transmit the echo light transmitted by the scanning module to the receiving lens unit.

23. The laser radar according to claim 22, characterized in that: The light splitting unit comprises: a polarization light splitting element and a wave plate, and the wave plate is located in the light path between the polarization light splitting element and the scanning module.

24. The laser radar according to claim 23, characterized in that The wave plate is attached to a surface of the polarization beam splitting element facing the scanning module.

25. The laser radar according to any one of claims 1 to 24, characterized in that: The scanning module comprises a polygonal mirror, the polygonal mirror comprises a plurality of reflecting surfaces, and the plurality of reflecting surfaces all rotate around a rotation axis; and different reflecting surfaces among the plurality of reflecting surfaces have the same angle portion with the rotation axis.

26. The laser radar according to claim 25, characterized in that The polygonal mirror has an even number of reflecting surfaces, wherein adjacent reflecting surfaces among the reflecting surfaces have different included angles with the rotation axis, and spaced reflecting surfaces among the reflecting surfaces have the same included angle with the rotation axis.

Images