Laser radar

Abstract

The invention provides a laser radar. The laser radar comprises an optical transceiver module and a scanning module, the optical transceiver module comprises: a transmitting unit; an emission lens unit configured to transmit the probe light; the receiving lens unit is separated from the transmitting lens unit, and the receiving lens unit is configured to transmit echo light formed by reflection of the detection light through an object; the receiving unit comprises a two-dimensional array detector; the scanning module is configured to receive the detection light and emit the detection light to the outside of the laser radar, and receive the echo light and emit the echo light to the light transceiver module. According to the laser radar with the scanning module, the two-dimensional array detector is adopted, so that the receiving view field angle corresponding to each detector in the laser radar can be reduced, and the optical resolution of a laser radar optical system can be improved; and the aberration of the transmitting lens unit and the receiving lens unit can be improved through the transmitting lens unit and the receiving lens unit which are separately arranged, so that the batch production is facilitated, and the area requirement on the two-dimensional array detector can be reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of lidar, and particularly to a lidar. Background Art

[0002] A lidar is a commonly used ranging sensor, which has the characteristics of long detection distance, high resolution, and small environmental interference, and is widely used in fields such as unmanned driving, intelligent robots, and drones. In recent years, the development of autonomous driving technology has been rapid, and lidar, as the core sensor for distance perception, has become indispensable.

[0003] In a lidar, a light beam is reflected by a reflecting surface of a scanning module to form a scanning light beam for spatial scanning. The scanning module for the lidar realizes the scanning of the scanning light beam within the field of view of the lidar through the reciprocating movement of the reflecting surface.

[0004] However, in existing lidars, the receiving field of view angles corresponding to each detector are relatively large, resulting in weak ability of the lidar to distinguish targets. Moreover, the methods for reducing the receiving field of view angle and improving the target discrimination ability are likely to cause deterioration of the aberration of the optical system of the lidar, and problems of high production difficulty and high production cost. Summary of the Invention

[0005] The problem solved by the present disclosure is how to improve the aberration, reduce the production difficulty, and reduce the production cost while improving the ability of the lidar to distinguish targets.

[0006] To solve the above problems, the present disclosure provides a lidar, including: an optical transceiver module and a scanning module; the optical transceiver module includes: a transmitting unit configured to generate detection light; a transmitting lens unit configured to transmit the detection light; a receiving lens unit separated from the transmitting lens unit and configured to transmit the echo light formed by the reflection of the detection light by an object; a receiving unit including: a two-dimensional array detector configured to detect the echo light passing through the receiving lens unit; the scanning module is configured to receive the detection light and emit it outside the lidar, and receive the echo light and emit it to the optical transceiver module.

[0007] Optionally, the transmitting lens unit includes a reflecting mirror and a transmitting lens, the transmitting lens includes at least 1 transmitting lens, and the reflecting mirror is configured to reflect the detection light to the scanning module.

[0008] Optionally, the receiving lens unit includes a receiving lens, and the receiving lens includes at least 1 receiving lens.

[0009] Optionally, 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 lidar.

[0010] Optionally, the focal length of the receiving lens is not greater than the focal length of the transmitting lens of the transmitting lens unit.

[0011] Optionally, the receiving component is located between the transmitting component and the scanning module, where 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.

[0012] Optionally, the size of the pixels in the two-dimensional array detector is greater than the optical parameters of the receiving lens.

[0013] Optionally, the receiving aperture of the receiving lens is greater than 8 mm.

[0014] Optionally, the F-number of the receiving lens is less than 4.

[0015] Optionally, the laser of the transmitting unit and the two-dimensional array detector of the receiving unit are arranged on the same circuit board.

[0016] Optionally, the optical transceiver module further includes: a support member, and at least the transmitting lens unit is fixed to the support member.

[0017] Optionally, both the transmitting lens unit and the beam splitting unit are fixed to the support member.

[0018] Optionally, the optical transceiver module further includes: a receiving lens support member, the receiving lens is fixed to the receiving lens support member, and the receiving lens support member is movably connected to the support member.

[0019] Optionally, there are multiple focusing marks on the circuit board for fixing the two-dimensional array detector.

[0020] Optionally, the receiving lens unit, the transmitting lens unit, and the beam splitting unit are all fixed to the support member.

[0021] Optionally, the receiving unit includes one two-dimensional array detector, and the two-dimensional array detector includes: multiple detection areas, and multiple said detection areas correspond one-to-one with multiple lasers of the transmitting unit.

[0022] Optionally, the two-dimensional array detector further includes: a compensation area, and the compensation area surrounds multiple said detection areas.

[0023] Optionally, the receiving unit includes multiple two-dimensional array detectors, and multiple two-dimensional array detectors correspond one-to-one with multiple lasers of the transmitting unit.

[0024] Optionally, multiple of the two-dimensional array detectors are arranged in an array; the two-dimensional array detectors in adjacent columns are arranged staggeredly in the column direction or the two-dimensional array detectors in adjacent rows are arranged staggeredly in the row direction.

[0025] Optionally, the two-dimensional array detector includes a plurality of pixels, and each pixel includes a plurality of detection elements.

[0026] Optionally, the detection element is a single-photon detection element.

[0027] Optionally, the optical transceiver module further includes: a beam splitting unit 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.

[0028] Optionally, the beam splitting unit includes: a polarization beam splitting element and a wave plate, and the wave plate is located in the optical path between the polarization beam splitting element and the scanning module.

[0029] Optionally, the wave plate is attached to the surface of the polarization beam splitting element facing the scanning module.

[0030] Optionally, the scanning module includes a polygonal mirror, the polygonal mirror includes a plurality of reflecting surfaces, and all of the plurality of reflecting surfaces rotate around a rotation axis; the angles between different reflecting surfaces and the rotation axis are partially the same.

[0031] Optionally, the polygonal mirror has an even number of reflecting surfaces, wherein the angles between adjacent reflecting surfaces and the rotation axis are different, and the angles between spaced-apart reflecting surfaces and the rotation axis are the same.

[0032] Compared with the prior art, the technical solution of the present disclosure has the following advantages:

[0033] In the technical solution of the present disclosure, in the receiving unit, a two-dimensional array detector is used to receive the echo light, which can effectively reduce the receiving field of view angles corresponding to the detectors in the lidar, is beneficial to improving the optical resolution of the lidar optical system, and is beneficial to enhancing the ability of the lidar to distinguish targets; for the two-dimensional array detector, in the optical transceiver module, a separate transmitting lens unit and receiving lens unit are used to transmit the detection light and the echo light respectively. By using different lens units to transmit the detection light and the echo light respectively, the detection light and the echo light are not transmitted through the same lens unit, which is beneficial to improving the aberration of the transmitting lens unit and the receiving lens unit, facilitating mass production, and effectively reducing the area requirement for the two-dimensional array detector, which is beneficial to reducing costs.

[0034] In an alternative embodiment of the present disclosure, the focal length of the receiving lens is not greater than the focal length of the transmitting lens of the transmitting lens unit. A transmitting lens with a larger focal length is adapted to a laser with a larger light-emitting area, and a receiving lens with a smaller focal length is adapted to a detector with a smaller photosensitive area; a transmitting lens with a larger focal length and a receiving lens with a smaller focal length are suitable for a laser with a larger light-emitting area and a detector with a smaller photosensitive area while matching the transmitting and receiving fields of view, which is beneficial to providing the ranging ability of the lidar.

[0035] In an alternative embodiment of the present disclosure, the size of the pixels in the two-dimensional array detector is greater than the optical parameter of the receiving lens. The optical parameter 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 parameter of the receiving lens affects the point cloud quality, optical resolution, etc. obtained by the two-dimensional array detector. Matching the size of the pixels in the two-dimensional array detector and the optical parameter of the receiving lens is beneficial to improving the optical resolution of the lidar, obtaining the best imaging quality, and providing the point cloud quality of the lidar.

[0036] In an alternative embodiment of the present disclosure, the receiving aperture of the receiving lens is greater than 8 mm. The larger the receiving aperture of the receiving lens, the higher the receiving efficiency of the lidar for the return light, and the stronger the ranging ability of the lidar. A sufficiently large receiving aperture of the receiving lens is beneficial to providing the receiving efficiency of the return light and improving the ranging ability of the lidar.

[0037] In an alternative embodiment of the present disclosure, the F-number of the receiving lens is less than 4. The F-number of a lens, such as the aperture coefficient of the lens, is the ratio of the focal length of the lens to the clear aperture. The luminous flux of the lens is inversely proportional to the square of the F-number. The smaller the F-number of the receiving lens, the larger the receiving aperture of the receiving lens, and the higher the receiving efficiency of the return light. A sufficiently small F-number of the receiving lens is beneficial to improving the receiving efficiency of the return light.

[0038] In an alternative embodiment of the present disclosure, 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 beneficial to the mass production of the lidar.

[0039] In an alternative embodiment of the present disclosure, the two-dimensional array detector further includes: a compensation area surrounding a plurality of the detection areas. The two-dimensional array detector can be driven in an addressable manner; the two-dimensional array detector realizes the alignment of the transmitting field of view and the receiving field of view through addressable driving, compensates for the error of the alignment of the transmitting field of view and the receiving field of view by using the compensation area, reduces the difficulty of optical alignment and adjustment, and even avoids the process of optical alignment and adjustment, which is beneficial to realizing the alignment-free adjustment of the laser and the detector integrated on the same board.

[0040] In an alternative embodiment of the present disclosure, the beam splitting unit includes a polarization beam splitting element and a wave plate, and the wave plate is located in the optical path between the polarization beam splitting element and the scanning module. The solution of splitting light using the polarization principle is beneficial to effectively improving the emission efficiency under the volume constraint of the lidar, and is beneficial to the improvement of the lidar performance.

[0041] In an alternative embodiment of the present disclosure, the wave plate is attached to the surface of the polarization beam splitting element facing the scanning module. By directly attaching the wave plate to the surface of the polarization beam splitting element, anti-reflection films do not need to be provided on the surfaces of the wave plate and the polarization beam splitting element that are attached to each other, which is beneficial to effectively reducing the coating cost; moreover, the two are fixedly connected, which is beneficial to effectively reducing the positioning surface, reducing the mechanical design complexity and cost; in addition, the two are fixedly connected, which is also beneficial to reducing the number of assembly components and reducing the production cost; in addition, the polarization beam splitting element is a flat plate structure, which has a lower cost compared to the polarization beam splitting element of the prism structure, and is beneficial to further reducing the cost of the lidar.

[0042] In an alternative embodiment of the present disclosure, the scanning module includes a multi-faceted mirror, the multi-faceted mirror includes a plurality of reflecting surfaces, and the plurality of reflecting surfaces all rotate around a rotating shaft; the angles between different reflecting surfaces and the rotating shaft are partially the same. The angles between different reflecting surfaces and the rotating shaft are partially the same, which realizes the adjustment of different field-of-view directions. While expanding the vertical field-of-view range of the lidar, it does not increase the difficulty of lens design, does not require an increase in the lens aperture, reduces costs, and is also beneficial to reducing the size of the circuit board for setting the laser and the two-dimensional array detector, and is beneficial to effectively reducing the height of the lidar. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present disclosure. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings. The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. They are used together with the embodiments of the present disclosure to explain the present disclosure, and do not constitute a limitation to the present disclosure. In the drawings:

[0044] Figure 1 is a functional block diagram of some embodiments of the lidar of the present disclosure;

[0045] Figure 2 is Figure 1 a schematic structural diagram of the transmitting unit in some embodiments of the lidar shown;

[0046] Figure 3 is Figure 1Schematic diagram of the optical path structure of some embodiments of the lidar shown;

[0047] Figure 4 is Figure 1 Schematic diagram of the field of view of some embodiments of the lidar shown;

[0048] Figure 5 is the functional block diagram of some other embodiments of the lidar of the present disclosure;

[0049] Figure 6 is Figure 5 Schematic diagram of the optical path structure of some other embodiments of the lidar shown;

[0050] Figure 7 is Figure 5 Schematic diagram of the structure of the transmitting unit in another embodiment of the lidar shown. Detailed implementation manners

[0051] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present disclosure. The drawings and the description are considered to be exemplary in nature and not restrictive.

[0052] In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as a limitation of the present disclosure. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present disclosure, "a plurality" means two or more unless otherwise clearly defined.

[0053] In the description of the present disclosure, in some embodiments, unless otherwise clearly defined or limited, the terms "mounted", "connected", and "coupled" shall be construed broadly. For example, it may be a fixed connection, a detachable connection, or an integral connection: it may be a mechanical connection, an electrical connection, or a connection capable of mutual communication; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure may be understood according to specific circumstances.

[0054] In the present disclosure, unless otherwise clearly defined or limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0055] The following disclosure provides many different embodiments or examples for implementing different structures of the present disclosure. To simplify the disclosure of the present disclosure, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present disclosure. In addition, the present disclosure may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present disclosure provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use of other materials.

[0056] As can be seen from the background art, it is difficult for lidars in the prior art to simultaneously address the problems of reducing the receiving field of view angle, improving the ability of the lidar to resolve targets, improving the aberration of the optical system, reducing the production difficulty, and reducing the production cost.

[0057] To solve the above technical problems, the present disclosure provides one, including: an optical transceiver module and a scanning module;

[0058] The optical transceiver module includes: a transmitting unit configured to generate detection light; a transmitting lens unit configured to transmit the detection light; a receiving lens unit separated from the transmitting lens unit and configured to transmit the echo light formed by the reflection of the detection light by an object; a receiving unit including: a two-dimensional array detector configured to detect the echo light passing through the receiving lens unit; and the scanning module is configured to receive the detection light and emit it outside the lidar, and receive the echo light and emit it to the optical transceiver module.

[0059] In the technical solution of the present disclosure, in the receiving unit, a two-dimensional array detector is used to receive the echo light, which is beneficial to effectively reduce the receiving field of view angle corresponding to each detector in the lidar, beneficial to improve the optical resolution of the lidar optical system, and beneficial to enhance the ability of the lidar to distinguish targets; for the two-dimensional array detector, in the optical transceiver module, a separated transmitting lens unit and receiving lens unit are used to transmit the detection light and the echo light respectively. By using different lens units to transmit the detection light and the echo light respectively, the detection light and the echo light are not transmitted through the same lens unit, which is beneficial to effectively improve the aberration of the transmitting lens unit and the receiving lens unit, facilitate mass production, and is also beneficial to effectively reduce the area requirement for the two-dimensional array detector and reduce costs.

[0060] To make the above objects, features, and advantages of the present disclosure more obvious and understandable, the following describes the specific embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0061] Reference Figure 1 shows a functional block diagram of some embodiments of the lidar of the present disclosure.

[0062] The lidar includes: an optical transceiver module 101 and a scanning module 102; the optical transceiver module 101 includes: a transmitting unit 110 configured to generate detection light 119; a transmitting lens unit 120 configured to transmit the detection light 119; a receiving lens unit 130 separated from the transmitting lens unit 120 and configured to transmit the echo light 149 formed by the reflection of the detection light 119 by an object; a receiving unit 140 including: a two-dimensional array detector 141 configured to detect the echo light 149 passing through the receiving lens unit 130; and the scanning module 102 is configured to receive the detection light 119 and emit it outside the lidar, and receive the echo light 149 and emit it to the optical transceiver module 101.

[0063] In the receiving unit, the two-dimensional array detector 141 is used to receive the backscattered light 149, which is beneficial to effectively reduce the receiving field of view angle corresponding to each detector in the lidar, improve the optical resolution of the lidar optical system, and enhance the ability of the lidar to resolve targets. For the two-dimensional array detector 141, in the optical transceiver module 101, the separated transmitting lens unit 120 and receiving lens unit 130 are used to transmit the detection light 119 and the backscattered light 149 respectively. By using different lens units to transmit the detection light 119 and the backscattered light 149, and the detection light 119 and the backscattered light 149 are not transmitted through the same lens unit, it is beneficial to improve the aberration of the transmitting lens unit 120 and the receiving lens unit 130, facilitate mass production, and is also beneficial to reduce the area requirement for the two-dimensional array detector 141 and reduce the cost.

[0064] The following will describe in detail the specific technical solutions of the lidar embodiments with reference to the accompanying drawings.

[0065] The optical transceiver module 101 is suitable for the transmission and reception of optical signals.

[0066] The transmitting unit 110 is suitable for generating the detection light 119.

[0067] In some embodiments, the transmitting unit 110 includes a plurality of light sources 111, and each light source 111 generates a beam of detection light 119. Among them, the light source can be a laser. For example, the laser can be a vertical-cavity surface-emitting laser (abbreviated as VCSEL). In some embodiments, the laser can also be an edge-emitting laser (abbreviated as EEL), etc., or other light-emitting components that generate laser light. The wavelength of the laser light emitted by the laser can be any one of 905 nm, 940 nm, and 1550 nm, or it can also emit laser light of other wavelengths.

[0068] In some embodiments of the present disclosure, the plurality of light sources 111 of the transmitting unit 110 are vertical-cavity surface-emitting lasers, and the detection light 119 generated by the vertical-cavity surface-emitting lasers is polarized light, such as P-polarized light.

[0069] As Figure 2 shown, the plurality of light sources 111 of the transmitting unit 110 are arranged in an array, and the light sources 111 in adjacent columns are staggered along the column direction. In other embodiments, the light sources 111 in adjacent rows are staggered along the row direction.

[0070] In some embodiments, Figure 2The figure shows two columns of the light sources 111 in the transmitting unit 110. However, in other embodiments of the present disclosure, the transmitting unit 110 may also have light sources with other numbers of columns, such as three columns, four 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 other embodiments of the present disclosure, among the multiple light sources 111 arranged in an array, the column direction corresponds to the vertical field of view direction of the lidar, and the column direction corresponds to the direction perpendicular to the horizontal plane; the row direction corresponds to the horizontal field of view direction of the lidar, and the row direction corresponds to the direction parallel to the horizontal plane.

[0072] The transmitting lens unit 120 transmits the detection light 119 for collimation and optical path adjustment.

[0073] As Figure 1 shown in some embodiments, the transmitting lens unit 120 includes a mirror 121 and a transmitting lens 122. The transmitting lens 122 includes at least one transmitting lens. The mirror 121 of the transmitting lens unit 120 is configured to reflect the detection light 119 to the scanning module 102.

[0074] The mirror 121 is used to change the optical path of the detection light 119, and the transmitting lens 122 is used to collimate the detection light 119. For example, the transmitting lens 122 includes multiple transmitting lenses, the transmitting lenses are spherical lenses or aspherical lenses, and the optical axes of the multiple transmitting lenses coincide. As Figure 1 shown in some embodiments, the number of transmitting lenses in the transmitting lens 122 is in the range of 2 to 6; as Figure 2 shown, the mirror 121 is arranged in the optical path between two of the multiple transmitting lenses.

[0075] In some embodiments, the optical transceiver module 101 further includes: a support member 160, and at least the transmitting lens unit 120 is fixed to the support member 160.

[0076] The support member 160 serves to carry and position the optical elements. The support member 160 is only one mechanical part. Using one mechanical part to carry the optical elements is beneficial to mass production.

[0077] As Figure 1 shown in some embodiments, the transmitting lens unit 120 is fixed to the support member 160, and all the transmitting lenses and the mirror 121 in the transmitting lens 122 are fixedly connected to the support member 160.

[0078] As Figure 1 and Figure 3In some of the illustrated embodiments, the optical transceiver module 101 further includes: a beam splitting unit 170 configured to transmit the detection light 119 transmitted by the transmitting lens unit 120 to the scanning module 102, and the beam splitting unit 170 is further configured to transmit the return light 149 transmitted by the scanning module 102 to the receiving lens unit 130.

[0079] The beam splitting unit 170 is used to separate the optical paths of the detection light 119 and the return light 149. In some embodiments, the beam splitting unit 170 includes: a polarization beam splitting element 172 and a wave plate 171, and the wave plate 171 is located in the optical path between the polarization beam splitting element 172 and the scanning module 102. For example, the polarization beam splitting element 172 may be a polarization beam splitting film, and the wave plate 171 is a quarter-wave plate. Implementing beam splitting using the polarization principle is beneficial for obtaining higher emission efficiency under the volume constraint of the lidar, and is beneficial for ensuring the long-distance measurement ability of the lidar; moreover, since the polarization beam splitting element 172 is a polarization beam splitting film, compared with the polarization beam splitting element with a prism structure, the polarization beam splitting element with a flat plate structure has a lower cost, which is beneficial for further cost control.

[0080] As Figure 3 shown, in some embodiments, the wave plate 171 is attached to the surface of the polarization beam splitting element 172 facing the scanning module 102. Directly attaching the wave plate 171 to the surface of the polarization beam splitting element 172 is beneficial for effectively reducing the number of separated components in the lidar. By directly attaching the wave plate 171 to the surface of the polarization beam splitting element 172, anti-reflection films do not need to be provided on the surfaces of the wave plate 171 and the polarization beam splitting element 172 that are in contact, which is beneficial for effectively reducing the coating cost; moreover, since the two are fixedly connected, it is beneficial for effectively reducing the positioning surfaces, reducing the mechanical design complexity and the cost of mechanical parts; in addition, since the two are fixedly connected, it is also beneficial for reducing the number of assembly components and the production cost.

[0081] In some embodiments, the detection light incident on the polarization beam splitting element 172 is linearly polarized light, such as P-polarized light; specifically, linearly polarized light can be directly generated by a vertical cavity surface emitting laser, or linearly polarized light can be formed using a polarizer. The polarization beam splitting element 172 converts the incident linearly polarized light into circularly polarized light for output, and after the detection light 119 in a circularly polarized state passes through the wave plate 171, it exits from the beam splitting unit 170.

[0082] In addition, Figure 1In some of the illustrated embodiments, the transmitting lens unit 120 is fixed to the support member 160, and the beam splitting unit 170 is also fixed to the support member 160. Both the transmitting lens unit 120 and the beam splitting unit 170 are fixed to the support member. All the transmitting lenses in the transmitting lens 122, the reflecting mirror 121, and the polarization beam splitter element 172 and the wave plate 172 in the beam splitting unit 170 are fixedly connected to the support member 160.

[0083] Continuing to refer to Figure 1 , the scanning module 102 is configured to change the exit direction of the detection light 119 to form a scanning field of view. The scanning module 102 reflects the detection light 119 outside the lidar, and the scanning module 102 reflects the return light 149 to the optical transceiver module 101.

[0084] As Figure 1 shown in some embodiments, the scanning module 102 is a one-dimensional scanning module. Specifically, as Figure 3 shown, the scanning module 102 includes a unidirectionally rotating mirror (hereinafter referred to as a rotating mirror). In some other embodiments of the present disclosure, the scanning module 102 may further include a galvanometer, and the galvanometer includes a MEMS mirror and a Galvo mirror.

[0085] In some embodiments of the present disclosure, the scanning module 102 includes a multi-faceted mirror 102a, the multi-faceted mirror includes a plurality of reflecting surfaces 102b, and the plurality of reflecting surfaces 102b all rotate around the rotating shaft 102c; the angles between different reflecting surfaces 102b and the rotating shaft 102c are partially the same, and the angle between at least one of the reflecting surfaces 102b and the rotating shaft 102c is different from the angle between other reflecting surfaces 102b and the rotating shaft 102c.

[0086] As Figure 3 shown, the multi-faceted mirror 102a is a four-sided mirror, the multi-faceted mirror 102a has 4 reflecting surfaces 102b, and the angles between the 4 reflecting surfaces 102b and the rotating shaft 102c are partially the same; among the 4 reflecting surfaces 102b, the angle between at least one of the reflecting surfaces 102b and the rotating shaft 102c is different from the angle between other reflecting surfaces 102b and the rotating shaft 102c.

[0087] In some embodiments of the present disclosure, the multi-faceted mirror has an even number of reflecting surfaces, and the angles between adjacent reflecting surfaces and the rotating shaft are different, and the angles between the spaced-apart reflecting surfaces and the rotating shaft are the same. As Figure 3 shown, among the four-sided mirrors 102a of the scanning module 102, the angles between the 4 reflecting surfaces 102b and the rotating shaft 102c are +1°, -1°, +1°, and -1° in sequence.

[0088] In some embodiments, the positive and negative values of the angle between the reflecting surface 102b and the rotating shaft 102c indicate different directions of the angle formed by the reflecting surface 102b and the rotating shaft 102c. The reflecting surfaces 102b with an angle of +1° with the rotating shaft 102c have the same angle direction, and the angle direction of the reflecting surface 102b with an angle of +1° with the rotating shaft 102c is opposite to the angle direction of the reflecting surface 102b with an angle of -1° with the rotating shaft 102c.

[0089] Figure 3 In some of the illustrated embodiments, the scanning module 102 is used to implement the scanning of the detection light 119 in the horizontal direction to form the horizontal field of view of the lidar. The rotating shaft 102c of the multi-mirror 102a intersects with the horizontal plane, for example, they are perpendicular to each other. The vertical field of view range of the detection light 119 transmitted by the beam splitting unit 170 is from -11° to +11°; the vertical field of view range formed by the detection light 119 reflected and emitted by the scanning module 102 is from -13° to +13°.

[0090] As Figure 4 shown, the vertical field of view (the vertical field of view of the lidar) formed by the emitted detection light 119 includes: a central region 105c and edge regions 105m located on both sides of the central region 105c. Among them, the vertical field of view range corresponding to the central region 105c is from -9° to +9°, and the edge regions 105m are respectively from -13° to -9° and from +9° to +13°. The detection light 119 reflected by all the reflecting surfaces 102b covers the central region 105c, while the detection light 119 reflected by adjacent reflecting surfaces 102b covers different edge regions 105m. For example, the detection light 119 reflected by one reflecting surface 102b covers the upper edge region 105m, and the detection light 119 reflected by the adjacent reflecting surface 102b covers the lower edge region 105m; the frame rate of the central region 105c is higher, and the frame rate of the edge region 105m is lower. The central region 105c is a high-frame-rate region, and the edge region 105m is a low-frame-rate region.

[0091] Through the design of the angles between different reflecting surfaces 102b of the multi-mirror 102a in the scanning module 102 and the rotating shaft 102c, the adjustment of different field of view directions is realized. While expanding the field of view range, it does not increase the difficulty of lens design, does not require an increase in the lens aperture, reduces costs, and is also beneficial to reducing the height of the lidar.

[0092] As Figure 1 and Figure 3As shown, the scanning module 102 is located in the optical path between the beam splitting unit 170 and the external space of the lidar. The scanning module 102 receives the detection light 119 transmitted by the beam splitting unit 170 and reflects the received detection light 119 to the external space of the lidar; the scanning module 102 also receives the echo light 149 formed by the detection light 119 reflected by an object in the external space and reflects the received echo light 149 to the beam splitting unit 170; the beam splitting unit 170 further transmits the echo light 149 to the receiving lens unit 130.

[0093] The detection light 119 that is transmitted by the beam splitting unit 170 and is circularly polarized is reflected by the scanning module 102 to the outside of the lidar, and the echo light 149 is formed after being reflected by an object. Without considering the depolarization effect during the external transmission of the lidar, the polarization state of the echo light 149 is substantially the same as that of the detection light 119, and the echo light 149 is also circularly polarized.

[0094] The scanning module 102 reflects the received echo light 149 to the beam splitting unit 170; the echo light 149 incident on the beam splitting unit 170 is transmitted through the wave plate 171 and then incident on the polarization beam splitting element 172.

[0095] During the process of beam transmission, the detection light 119 exits from the polarization beam splitting element 172 and is transmitted through the wave plate 171 to the scanning module 102. The echo light 149 is also transmitted through the wave plate 171 and then incident on the polarization beam splitting element 172. And the echo light 149 is reflected by the polarization beam splitting element 172 and then transmitted through the wave plate 171 again. The echo light is transmitted through the wave plate 171 twice. Since the wave plate 171 is a quarter-wave plate, compared with the detection light 119 exiting from the polarization beam splitting element 172 and the echo light 149 incident on the beam splitting unit 170, the phase of the echo light 149 exiting from the beam splitting unit 170 changes by π / 2, and the echo light is still circularly polarized. The polarization beam splitting element 172 transmits the incident echo light 149 in the direction of the receiving lens unit 130, realizing the separation of the optical path of the detection light 119 and the optical path of the echo light 149.

[0096] The receiving lens unit 130 is separated from the transmitting lens unit 120. The receiving lens unit 130 is located downstream of the beam splitting unit 170 in the optical path of the echo light 149. The receiving lens unit 130 is configured to converge the echo light 149 to the receiving unit 140.

[0097] In some embodiments, the receiving lens unit 130 includes: a receiving lens 131, and the receiving lens 131 includes at least one receiving lens. AsFigure 1 and Figure 3 In some of the embodiments shown, the optical path in the receiving lens unit 130 does not change. For example, the receiving lens unit 130 does not include a reflector.

[0098] The receiving lens 131 converges the return light 149 transmitted by the beam splitting unit 170 to the receiving unit 140. For example, the receiving lens 131 includes a plurality of receiving lenses, the receiving lenses are spherical lenses or aspherical lenses, and the optical axes of the plurality of receiving lenses coincide. As Figure 1 In some of the embodiments shown, the number of receiving lenses in the receiving lens 131 is in the range of 2 to 6.

[0099] In some embodiments of the present disclosure, the focal length of the receiving lens 131 is not 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 is less than the focal length of the transmitting lens 122 of the transmitting lens unit 120.

[0100] The focal length of the transmitting lens 122 is larger and is adapted to the transmitting unit 110 with a larger light emitting area. The focal length of the receiving lens 131 is smaller and is adapted to the two-dimensional array detector 141 in the receiving unit 140 with a smaller photosensitive area. The transmitting lens 122 with a larger focal length and the receiving lens 131 with a smaller focal length are more suitable for the transmitting unit 110 with a large light emitting area and the receiving unit 140 with a small photosensitive area, which is beneficial to ensuring the ranging ability of the lidar while achieving the matching of the transmitting and receiving fields of view.

[0101] In some embodiments, the transceiver module 101 has a transmitting component 103 and a receiving component 104, wherein the transmitting component 103 includes: the transmitting unit 110 and the transmitting lens unit 120, and the receiving component 104 includes: the receiving lens unit 130 and the receiving unit 140; As Figure 1 and Figure 3 shown, the receiving component 104 is located between the transmitting component 103 and the scanning module 102. Setting the receiving component 104 between the transmitting component 103 and the scanning module 102 is adapted to the transmitting lens 122 with a larger focal length and the receiving lens 131 with a smaller focal length, and the optical path setting is more reasonable.

[0102] In some embodiments of the present disclosure, the receiving aperture of the receiving lens 131 is greater than 8 mm. The larger the receiving aperture of the receiving lens 131, the stronger the ranging ability of the lidar. The receiving aperture of the receiving lens 131 is large enough to obtain sufficient ranging ability.

[0103] In some embodiments of the present disclosure, the F-number of the receiving lens 131 is less than 4. The F-number of a lens, such as the aperture coefficient of the lens, is the ratio of the focal length of the lens to the clear aperture. The luminous flux of the lens is inversely proportional to the square of the F-number. The smaller the F-number of the receiving lens 131, the larger the receiving aperture of the receiving lens 131, and the higher the receiving efficiency of the return light 149. In some embodiments, the F-number of the receiving lens 131 is less than 1.8.

[0104] In some embodiments of the present disclosure, the focal length of the receiving lens 131 is determined according to the interval between adjacent pixels in the two-dimensional array detector 141 and the angular resolution of the lidar. For example, if the interval between adjacent pixels in the two-dimensional array detector 141 is Δd, and the angular resolution of the lidar is Δθ, the focal length f of the receiving lens 131 is:

[0105] In some embodiments of the present disclosure, the optical transceiver module 101 further includes the support member 160; the receiving lens unit 130, the transmitting lens unit 120, and the beam splitting unit 170 are all fixed to the support member 160, and the optical elements of the lidar do not need to be aligned, which helps to reduce the alignment difficulty of the lidar.

[0106] Continuing to refer Figure 1 and Figure 3 , the receiving unit 140 includes: a two-dimensional array detector 141, which is located in the optical path of the return light 149 downstream of the receiving lens unit 130, and the two-dimensional array detector 141 detects the return light 149 passing through the receiving lens unit 130.

[0107] For example, the two-dimensional array detector 141 includes a plurality of detection elements arranged in a two-dimensional manner. The detection element can be a single-photon detection element, and the single-photon detection element is a single-photon avalanche diode (Single-photon Avalanche Diode, abbreviated as SPAD).

[0108] In some embodiments, different from a plurality of individually packaged detectors arranged in a two-dimensional manner, the plurality of detection elements in the two-dimensional array detector 141 are driven in an addressable manner, and the distance between adjacent detection elements is smaller.

[0109] In still some embodiments, the plurality of detection elements of the two-dimensional array detector 141 are arranged in two intersecting directions. One direction corresponds to the vertical field of view direction of the lidar and corresponds to the direction perpendicular to the horizontal plane; the other direction corresponds to the horizontal field of view direction of the lidar and corresponds to the direction parallel to the horizontal plane.

[0110] In some embodiments of the present disclosure, the two-dimensional array detector 141 includes a plurality of pixels, and each of the pixels includes a plurality of detection elements. In some embodiments, the detection element is a single-photon detection element. Each pixel of the two-dimensional array detector 141 includes a plurality of the detection elements. For example, each pixel includes 4 single-photon avalanche diodes, and each pixel (such as 4 SPADs) outputs 1 signal for subsequent circuit sampling and processing.

[0111] In some embodiments of the present disclosure, the size of the pixels in the two-dimensional array detector 141 is greater than the optical parameters of the receiving lens 131. In some embodiments, the optical parameter is an image quality design parameter; for example, the optical parameter is the root mean square spot radius (RMS radius), which refers to the spot radius obtained by taking the square root after performing a quadratic average on the light intensity distribution and is an index used to describe the beam size.

[0112] The root mean square spot radius of the lens can affect the optical resolution of the point cloud obtained by the detector. A smaller root mean square spot radius indicates better optical performance, which helps to obtain a clearer point cloud and higher resolution; the pixel size is a key parameter of the two-dimensional array detector, and smaller pixels allow more details to be captured.

[0113] However, to obtain more detailed point clouds, in addition to a smaller detector pixel size, better lens performance is also required. If the pixel size is much smaller than the root mean square spot radius of the lens, potential resolution will be wasted.

[0114] Therefore, the best point cloud quality is achieved by the mutual cooperation of appropriate lens optical parameters and suitable pixel sizes. When the root mean square spot radius of the lens is less than or equal to the pixel size range, it is beneficial to better improve the resolution of the point cloud.

[0115] In some embodiments, each pixel of the two-dimensional array detector 141 includes a plurality of 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 greater than the root mean square radius of the receiving lens 131.

[0116] As Figure 2 In some embodiments shown, the receiving unit 140 includes 1 two-dimensional array detector 141, and the two-dimensional array detector 141 includes: a plurality of detection areas 141t, and the plurality of detection areas 141t correspond one-to-one to the plurality of lasers 111 of the transmitting unit 110.

[0117] The receiving unit 140 adopts an addressable manner of a two-dimensional array detector. Each laser of the transmitting unit 110 corresponds to one detection area 141t of the two-dimensional array detector 141 in the receiving unit 140. Each of the detection areas 141t includes at least one pixel. For example, each of the detection areas 141t includes: m×n pixels, where each pixel generates p point clouds. In the point cloud of the lidar, the number of points in the vertical field of view is n×p, which is conducive to realizing vertical field of view encryption and improving the density and resolution of the point cloud.

[0118] 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 range θ of the transmitting field of view tx are related as: f tx ×θ tx =S tx ; 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 range θ of the receiving field of view rx are related as: f rx ×θ rx =S rx .

[0119] When the light power density of the laser in the transmitting unit 110 is limited, a laser with a larger light-emitting area is beneficial to improving the ranging ability of the lidar, and the focal length f of the transmitting lens 122 tx is greater than the focal length f of the receiving lens 131 rx , which is beneficial to matching the transmitting and receiving fields of view and making the photosensitive area of the detection area 141t corresponding to the laser smaller, thereby being beneficial to improving the optical resolution of the lidar.

[0120] Continuing to refer to Figure 2 , in some embodiments, the two-dimensional array detector 141 further includes: a compensation area 141m, and the compensation area 141m surrounds a plurality of the detection areas 141t. The two-dimensional array detector 141 is driven in an addressable manner; the two-dimensional array detector 141 realizes the alignment of the transmitting field of view and the receiving field of view through addressable driving, compensates for the error of the alignment of the transmitting field of view and the receiving field of view by using the compensation area 141m, reduces the difficulty of optical alignment and adjustment, and even can avoid the optical alignment and adjustment process, which is beneficial to realizing the alignment-free adjustment of the integrated laser and detector on the same board.

[0121] In some embodiments of the present disclosure, the optical transceiver module 101 further includes: a circuit board 150, and the laser 111 of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 are fixed on the circuit board 150. As Figure 1 In some embodiments as shown, the laser 111 of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 are disposed on the same circuit board 150. The co-board integration of the laser of the transmitting unit and the two-dimensional array detector of the receiving unit is conducive to mass production.

[0122] The focal length f of the transmitting lens 122 tx is greater than the focal length f of the receiving lens 131 rx , and moreover, the focal length f of the transmitting lens 122 tx and the focal length f of the receiving lens 131 rx have an appropriate difference, so that the laser of the transmitting unit 110 and the two-dimensional array detector 141 of the receiving unit 140 can achieve co-board integration.

[0123] In some embodiments, as Figure 1 In some embodiments as shown, the receiving unit 140 further includes: a filter 142, the filter 142 is located in the optical path between the receiving lens 131 and the two-dimensional array detector 141, and the filter 142 is used to filter out stray light.

[0124] Refer to Figure 5 and Figure 6 , where Figure 5 shows a functional block diagram of some other embodiments of the lidar of the present disclosure; Figure 6 shows Figure 5 a schematic optical path structure diagram of the lidar embodiment shown.

[0125] For the same parts as the foregoing embodiments, the present disclosure will not be described herein again. The differences from the foregoing embodiments are that Figure 5 and Figure 6 In some embodiments as shown, the transmitting lens unit 220 and the beam splitting unit 270 are both fixed to the support member 260; the optical transceiver module 201 further includes: a receiving lens support member 261, the receiving lens 231 is fixed to the receiving lens support member 261, and the receiving lens support member 261 is movably connected to the support member 260.

[0126] Specifically, as Figure 6As shown, multiple receiving lenses of the receiving lens 231 in the receiving lens unit 230 are fixedly connected to the receiving lens support 261, and the receiving lens support 261 is movably fixed to the support 260. 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. By using the movable receiving lens support 261 and through active alignment (AA focusing) technology, the distance D between the receiving lens 231 and the two-dimensional array detector 241 of the receiving unit 140 is changed to achieve back focus adjustment of the receiving lens unit 230, so as to improve the optical resolution, improve the image quality of the lidar optical system, and improve the lidar's ability to distinguish targets.

[0127] In some embodiments, the receiving lens support 261 is fixed by at least one of welding and gluing. After the back focus adjustment of the receiving lens unit 230, the receiving lens support 261 and the support 260 are fixedly connected by at least one of welding and gluing.

[0128] In some embodiments, as Figure 7 shown, there are multiple focusing marks 262 on the circuit board 250 that fixes the two-dimensional array detector 241. The focusing marks 262 are used for alignment during the back focus adjustment process. The focusing marks 262 have a high-precision pattern. During the back focus adjustment process, according to the clarity of the pattern of the focusing marks 262, it is judged whether different field-of-view positions of the two-dimensional array detector 241 are at the optimal back focal plane position; the positions of the focusing marks 262 represent the pixel positions of the two-dimensional array detector 241 and are used for alignment of the emission field of view and the reception field of view.

[0129] For example, the shape of the focusing mark 262 is an inclined double rectangle. In other embodiments of the present disclosure, the shape of the focusing mark can also be circular, square, triangular, pentagonal, hexagonal, cross-shaped, target-shaped, etc.

[0130] In some embodiments, as Figure 7 shown in some embodiments, the receiving unit 240 includes multiple two-dimensional array detectors 241, and the multiple two-dimensional array detectors 241 correspond one-to-one with the multiple lasers 211 of the transmitting unit 210. The receiving unit 140 is constituted by the multiple two-dimensional array detectors 241, which is beneficial to reducing the area of a single two-dimensional array detector 241 and beneficial to reducing costs.

[0131] In some embodiments of the present disclosure, the two-dimensional array detector 141 includes a plurality of pixels, and each pixel includes a plurality of detection elements. In some embodiments, the detection element is a single-photon detection element, and the single-photon detection element is a single-photon avalanche diode (Single-photon Avalanche Diode, abbreviated as SPAD).

[0132] In some embodiments of the present disclosure, a plurality of the two-dimensional array detectors 241 are arranged in an array; the two-dimensional array detectors 241 in adjacent columns are arranged staggered in the column direction or the two-dimensional array detectors 241 in adjacent rows are arranged staggered in the row direction. As Figure 7 shown, a plurality of two-dimensional array detectors 241 are arranged in an array, and the two-dimensional array detectors 241 in adjacent columns are arranged staggered in the column direction. For example, one two-dimensional array detector in a certain column is located between two two-dimensional array detectors in the adjacent column in the column direction.

[0133] For example, Figure 7 shows 4 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 in 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 in the column direction.

[0134] In some embodiments of the present disclosure, there is an overlapping area between adjacent two-dimensional array detectors 241 along the staggering direction. For example, as Figure 7 shown, the two-dimensional array detector 241 in the first column 201 and the two-dimensional array detector 241 in the second column 202 adjacent in the column direction have an overlapping area in the column direction (as shown by the dotted line in Figure 7 ): The projections of the two-dimensional array detector 241 in the first column 201 and the two-dimensional array detector 241 in the second column 202 on the vertical plane have an overlapping area, where the vertical plane is the plane perpendicular to the direction from the first column 201 pointing to the second column 202.

[0135] It should be noted that in some embodiments of the present disclosure, adjacent two-dimensional array detectors along the staggering direction may also be completely staggered, and there is no overlapping area between adjacent two-dimensional array detectors along the staggering direction. For example, the two-dimensional array detector 241 in the first column 201 and the two-dimensional array detector 241 in the second column 202 adjacent in the column direction are completely staggered in the column direction and have no overlapping area.

[0136] The optical transceiver module includes: a transmitting lens unit configured to transmit the detection light and collimate the detection light; a receiving lens unit separated from the transmitting lens unit and configured to transmit the echo light formed by the reflection of the detection light by an object. By separately transmitting the detection light and the echo light through the separately arranged transmitting lens unit and receiving lens unit, the design of the transmitting lens unit only needs to meet the technical requirements for collimating 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 receiving the echo light, thereby improving the receiving 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 receiving effect of the echo light are both beneficial to improving the detection performance of the lidar.

[0137] In the receiving unit, a two-dimensional array detector is used to receive the echo light, which can effectively reduce the receiving field of view angle corresponding to each detector in the lidar, is beneficial to improving the optical resolution of the lidar optical system, and is beneficial to enhancing the ability of the lidar to distinguish targets. For the two-dimensional array detector, in the optical transceiver module, a separated transmitting lens unit and receiving lens unit are used to separately transmit the detection light and the echo light. By using different lens units to separately transmit the detection light and the echo light, the detection light and the echo light are not transmitted through the same lens unit, which is beneficial to improving the aberration of the transmitting lens unit and the receiving lens unit, facilitating mass production, and effectively reducing the area requirement for the two-dimensional array detector, which is beneficial to reducing costs.

[0138] Moreover, the focal length of the receiving lens is not greater than the focal length of the transmitting lens of the transmitting lens unit. A transmitting lens with a larger focal length is adapted to a laser with a larger light-emitting area, and a receiving lens with a smaller focal length is adapted to a detector with a smaller photosensitive area; a transmitting lens with a larger focal length and a receiving lens with a smaller focal length, while matching the transceiver field of view, are applicable to a laser with a larger light-emitting area and a detector with a smaller photosensitive area, which is beneficial to providing the long-distance measurement ability of the lidar.

[0139] In addition, the size of the pixels in the two-dimensional array detector is larger than the optical parameter of the receiving lens. The optical parameter of the receiving lens can 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 parameter of the receiving lens will affect the point cloud quality, optical resolution, etc. obtained by the two-dimensional array detector. The matching of the size of the pixels in the two-dimensional array detector and the optical parameter of the receiving lens is beneficial to improving the optical resolution of the lidar, is beneficial to obtaining the best imaging quality, and provides the point cloud quality of the lidar.

[0140] In addition, the receiving aperture of the receiving lens is greater than 8 mm. The larger the receiving aperture of the receiving lens, the higher the receiving efficiency of the lidar for the reflected light, and the stronger the ranging ability of the lidar. A sufficiently large receiving aperture of the receiving lens is conducive to providing the receiving efficiency of the reflected light and improving the ranging ability of the lidar.

[0141] In addition, the F-number of the receiving lens is less than 4. The F-number of a lens, such as the aperture coefficient of the lens, is the ratio of the focal length of the lens to the clear aperture. The luminous flux of the lens is inversely proportional to the square of the F-number. The smaller the F-number of the receiving lens, the larger the receiving aperture of the receiving lens, and the higher the receiving efficiency of the reflected light. A sufficiently small F-number of the receiving lens is conducive to improving the receiving efficiency of the reflected light.

[0142] In addition, the laser of the transmitting unit and the two-dimensional array detector of the receiving unit are arranged on the same circuit board. The co-board integration of the laser of the transmitting unit and the two-dimensional array detector of the receiving unit is conducive to the mass production of lidars.

[0143] In addition, the two-dimensional array detector further includes: a compensation area that surrounds a plurality of the detection areas. 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 addressable driving, uses the compensation area to compensate for the error in the alignment of the transmitting field of view and the receiving field of view, reduces the difficulty of optical alignment and adjustment, and can even avoid the process of optical alignment and adjustment, which is conducive to achieving the alignment-free adjustment of the co-board integrated laser and detector.

[0144] In addition, the beam splitting unit includes: a polarization beam splitting element and a wave plate, and the wave plate is located in the optical path between the polarization beam splitting element and the scanning module. The scheme of beam splitting using the polarization principle is conducive to effectively improving the transmission efficiency under the volume constraint of the lidar and is conducive to the improvement of the lidar performance.

[0145] In addition, the wave plate is attached to the surface of the polarization beam splitting element facing the scanning module. By directly attaching the wave plate to the surface of the polarization beam splitting element, anti-reflection films do not need to be provided on the surfaces of the wave plate and the polarization beam splitting element that are in contact, which is conducive to effectively reducing the coating cost; moreover, the two are fixedly connected, which is conducive to effectively reducing the positioning surface, reducing the mechanical design complexity and cost; in addition, the two are fixedly connected, which is also conducive to reducing the number of assembled components and reducing the production cost; in addition, the polarization beam splitting element is a flat plate structure, which has a lower cost compared to the polarization beam splitting element with a prism structure, and is conducive to further reducing the cost of the lidar.

[0146] In addition, the scanning module includes a polygon mirror, the polygon mirror includes a plurality of reflecting surfaces, and the plurality of reflecting surfaces all rotate around a rotating shaft; the included angles between different reflecting surfaces and the rotating shaft are partially the same. The fact that the included angles between different reflecting surfaces and the rotating shaft are partially the same realizes the adjustment of different viewing field directions, expands the vertical viewing field range of the lidar, does not increase the difficulty of lens design, does not need to increase the lens aperture, reduces costs, and is also beneficial to reducing the size of the circuit board for setting the laser and the two-dimensional array detector, and is beneficial to effectively reducing the height of the lidar.

[0147] Although the present disclosure is disclosed as above, the present disclosure is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and the protection scope of the present disclosure should be subject to the scope defined by the claims.

Claims

1. A laser radar, characterized in that: include: Optical transceiver module and scanning module; The optical transceiver module includes: a transmitting unit, the transmitting unit is 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, 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 claim 1, 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 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 claim 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 claim 1, 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 claim 1, characterized in that: 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.

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 claim 1, characterized in that: The two-dimensional array detector includes a plurality of pixels, and each of the 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 claim 1, 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 9, 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; The angles between different reflection surfaces and the rotation axis are the same.

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 have different included angles with the rotation axis, and spaced reflecting surfaces have the same included angle with the rotation axis.

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