A laser radar scanning method and computer readable storage medium

Abstract

The present invention discloses a laser radar scanning method and a computer-readable storage medium. The method comprises: a first light deflection device deflects a light beam emitted by a light source by a plurality of first deflection angles along a first direction; the length of the light beam emitted by the light source along the first direction is less than the length along a second direction; a second light deflection device deflects the light beam deflected by the first light deflection device by a plurality of second deflection angles along a first direction and a second direction to project a scanning light beam; the length of the scanning light beam in the first direction is less than its length in the second direction; the second deflection angle of the incident light beam deflected by the second light deflection device is adjusted by controlling the working voltage applied to the second light deflection device, and the corresponding working voltage applied is fine-tuned according to the incident angle of the light beam incident on the second light deflection device; wherein, for the same second deflection angle, different incident angles correspond to different working voltages.

Description

Technical Field

[0001] The present invention relates to the field of depth sensing technology, and in particular to a laser radar scanning method and a computer-readable storage medium. Background Art

[0002] In recent years, the commercialization of LiDAR in areas such as autonomous driving has been accelerating. Compared with traditional mechanical and semi-solid-state LiDARs, all-solid-state LiDARs have significant advantages in system cost and reliability.

[0003] The current mainstream direct time-of-flight (DTOF) Flash-type all-solid-state laser radar adopts a wide-area light emission method to cover the entire field of view angle. At the receiving end, a planar SPAD array is used to receive the reflected echo signal in a time-sharing and partitioned manner, ultimately achieving three-dimensional scanning imaging of targets ranging from several meters to tens of meters. Without changing the frame rate, scanning angle, and angular resolution, in order to meet the needs of vehicle navigation and obstacle avoidance, the detection distance needs to be increased to hundreds of meters. There is no mature solution for such a laser radar system. In order to meet the distance index, at the transmitting end, it is necessary to increase the spatial energy density of the emitted laser, or limit the emitted laser to a certain angle range, and achieve coverage of the entire field of view through a light deflection structure. The difficulty lies in how to simultaneously meet the requirements of long distance, high frame rate, and high angular resolution.

[0004] In order to achieve high frame rate, large field of view and long-distance scanning of LiDAR, liquid crystal light deflection technology is used in LiDAR to deflect the light beam. Liquid crystal plate deflection technology uses liquid crystal polarization grating to amplify the deflection angle. The liquid crystal half-wave plate in the cascaded liquid crystal polarization grating changes the angle of the incident light relative to the liquid crystal molecules when the light beam is not incident vertically. At the same time, due to the lengthening of the optical path through the liquid crystal layer due to oblique incidence, the phase delay changes, affecting the diffraction efficiency of the liquid crystal polarization grating. Summary of the invention

[0005] In view of the above problems, the present invention is proposed to provide a laser radar scanning method and a computer-readable storage medium that overcome the above problems or at least partially solve the above problems.

[0006] An embodiment of the present invention provides a laser radar scanning method, which includes:

[0007] The first light deflection device deflects the light beam emitted by the light source along a first direction by a plurality of first deflection angles to achieve a first level of light deflection; the length of the light beam emitted by the light source along the first direction is shorter than the length along the second direction;

[0008] The second light deflection device deflects the light beam deflected by the first light deflection device along the first direction and the second direction by a plurality of second deflection angles to achieve second-level light deflection and project a scanning light beam; the length of the scanning light beam in the first direction is less than the length thereof in the second direction;

[0009] The second deflection angle of the incident light beam deflected by the second light deflection device is adjusted by controlling the working voltage applied to the second light deflection device, and the corresponding applied working voltage is fine-tuned according to the incident angle of the light beam incident on the second light deflection device; wherein, for the same second deflection angle, different incident angles correspond to different working voltages.

[0010] In some optional embodiments, the second light deflection device is a liquid crystal polarization grating, which includes a liquid crystal half-wave plate and a liquid crystal polarization grating arranged in pair, and the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating is nematic liquid crystal or blue phase liquid crystal.

[0011] In some optional embodiments, the operating voltage applied to the second light deflection device includes a voltage applied to the liquid crystal half-wave plate and / or a voltage applied to the liquid crystal polarization grating, and the incident angle of the light beam incident on the second light deflection device is the angle difference between the incident direction of the light beam and a direction perpendicular to the light incident surface of the second light deflection device, and the operating voltage is positively correlated with the incident angle.

[0012] In some optional embodiments, the step of fine-tuning the corresponding applied operating voltage according to the incident angle of the light beam incident on the second light deflection device includes:

[0013] According to the incident angle and total light intensity of the light beam when it enters the liquid crystal half-wave plate, the thickness of the liquid crystal half-wave plate and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate, the optimal operating voltage applied to the liquid crystal half-wave plate corresponding to different incident angles is determined.

[0014] In some optional embodiments, the light beam emitted by the light source is a strip light beam with an aspect ratio of 20:1~100:1; the light beam incident on the first light deflection device has an aspect ratio of 3:1~1:2; and the scanning light beam is a strip light beam with an aspect ratio of 20:1~80:1.

[0015] In some optional embodiments, the method further includes: collimating the light beam before performing the first-order light deflection; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction; and the first direction is perpendicular to the second direction.

[0016] In some optional embodiments, the collimating the light beam comprises:

[0017] Collimate a light beam with an aspect ratio of A in a first direction with a first collimation index, and collimate it in a second direction with a second collimation index, to produce a light beam with an aspect ratio of B, wherein A>B, and the first collimation index is higher than the second collimation index;

[0018] After being deflected at the first deflection angle and the second deflection angle, the collimated light beam with an aspect ratio of B diverges into a light beam with an aspect ratio of C, and C>B.

[0019] In some optional embodiments, the following relationship is satisfied among the light emitting width V1 of the light source in the first direction, the divergence angle θ1 of the light source in the first direction, the beam waist diameter V2 in the first direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the first direction when the light beam is incident on the first light deflection device, and the focal length F2 of the collimating lens for collimating the light beam along the first direction: θ2= V1 / F2, θ2 V2=θ1 V1;

[0020] The following relationship is satisfied between the light emitting length H1 of the light source in the second direction, the divergence angle θ1 of the light emitted in the second direction, the beam waist diameter H2 in the second direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the second direction when the light beam is incident on the first light deflection device, and the focal length F1 of the collimating lens for collimating the light beam along the second direction: θ2= H1 / F1, θ2H2=θ1 H1.

[0021] In some optional embodiments, the method further includes: amplifying the deflection angle of the deflected light beam along the corresponding deflection direction by a preset multiple, and amplifying the divergence angle of the light beam by a corresponding preset multiple to form a strip light beam;

[0022] The divergence angle of the strip light beam along the second direction is greater than or equal to an angular interval between two adjacent second deflection angles along the second direction.

[0023] In some optional embodiments, the deflection angle of the deflected light beam along the corresponding deflection direction is magnified by a preset multiple, including: at least one expansion lens magnifies the deflection angle of the light beam deflected by the first optical deflection device or the second optical deflection device by a preset multiple in at least one of the first direction and the second direction perpendicular to each other.

[0024] In some optional embodiments, the deflection angle range of the light beam deflected along the first direction by a plurality of first deflection angles is greater than or equal to the angle interval between two adjacent second deflection angles of the light beam along the first direction;

[0025] The deflection accuracy of the light beam deflecting the first deflection angle is higher than the deflection accuracy of the light beam deflecting the second deflection angle.

[0026] In some optional embodiments, the light beam is deflected at a plurality of first deflection angles and a second deflection angle to scan a preset field of view, wherein the length of the field of view in the first direction is smaller than the length in the second direction;

[0027] In a deflection period, the plurality of different first deflection angles of the light beam change from large to small, or from small to large, or change according to a preset random rule in the first direction;

[0028] The plurality of second deflection angles for deflecting the light beam within one deflection period are all the same, or all different, or some are the same and some are different.

[0029] In some optional embodiments, the second light deflection device deflects the light beam after the first-order light is deflected by a plurality of second deflection angles along the first direction and the second direction, including:

[0030] The control device controls the multiple deflection sub-areas in the second light deflection device to receive the deflected light beams corresponding to the light beams with multiple different first deflection angles; each deflection sub-area can adjust the deflection angle of the light beam individually;

[0031] Controlling the deflection partition currently being scanned to deflect the light beam to a second deflection angle required; and

[0032] At least one deflection partition that is not currently scanned is controlled to adjust the deflection angle of the light beam to a second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the light beam and before the next deflection cycle is scanned by the light beam.

[0033] In some optional embodiments, the first light deflection device deflects the light beam along the first direction to a plurality of first deflection angles in one deflection period, including: the first light deflection device deflects the light beam to a plurality of different first deflection angles in a time-division manner in a preset order in one deflection period;

[0034] Controlling a plurality of deflection sub-areas in the second light deflection device to receive a plurality of incident light beams at different first deflection angles, comprising: controlling the plurality of deflection sub-areas to receive the light beams at different first deflection angles in a synchronous manner;

[0035] The deflection period is the time required for the first light deflecting device to deflect the incident light beam by all of a plurality of different first deflection angles, or the deflection period is the time required for the first light deflecting device to deflect the incident light beam by a specified portion of the first deflection angles.

[0036] In some optional embodiments, a deflection partition may sequentially receive one, two or more incident light beams with different first deflection angles within a deflection period;

[0037] The plurality of deflection partitions are configured such that the plurality of second deflection angles for light beam deflection in one deflection cycle are all the same, or are all different, or are partially the same and partially different;

[0038] The number of light beams that can be received by each deflection partition is the same, different, or partially the same and partially different; accordingly, the widths of the multiple deflection partitions are the same, different, or partially the same and partially different.

[0039] In some optional embodiments, the controlling of at least one deflection partition that is not currently scanned to adjust the deflection angle of the light beam to a second deflection angle required for the next deflection cycle after the light beam scans the current deflection cycle and before the light beam scans the next deflection cycle, comprises:

[0040] After determining that a deflection partition completes the beam deflection of the current deflection cycle and is in a non-scanning state, the deflection partition is controlled to adjust its deflection angle for the beam, and before entering the scanning state in the next deflection cycle, its deflection angle for the beam is adjusted to a second deflection angle required for the next deflection cycle.

[0041] In some optional embodiments, if a deflection partition is a deflection partition currently scanned by the light beam, it is determined that the deflection partition is in a scanning state, otherwise, it is determined that the deflection partition is in a non-scanning state; or

[0042] If a deflection partition is a deflection partition that is currently scanned by the light beam or is to be scanned next, it is determined that the deflection partition is in a scanning state; otherwise, it is determined that the deflection partition is in a non-scanning state.

[0043] In some optional embodiments, the deflection partition currently scanned by the light beam and the next deflection partition to be scanned are determined as deflection partitions in a scanning state, and the remaining deflection partitions are determined as deflection partitions in a non-scanning state; the deflection partition currently scanned by the light beam and the next deflection partition to be scanned are adjacent deflection partitions in position.

[0044] In some optional embodiments, the second optical deflection device includes at least one optical deflection unit, and the optical deflection unit includes a plurality of deflection sub-partitions. When the deflection sub-partitions include deflection sub-partitions corresponding to positions in the at least one optical deflection unit, the voltages on the electrodes at both ends of each deflection sub-partition are respectively controlled, and the deflection angle of the light beam by at least one deflection sub-partition is changed by changing the voltages on the electrodes at both ends of at least one deflection sub-partition, so as to achieve the second deflection angle of the light beam by changing the corresponding deflection sub-partition.

[0045] In some optional embodiments, the number D of deflection partitions is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second optical deflection device, F is the frame rate at which the second optical deflector deflects a round of M deflection angles, and T is the time required for the second optical deflection device to complete a deflection angle adjustment.

[0046] In some optional embodiments, the field of view of the light scan is divided into a plurality of scanning partitions, the scanning partitions are rectangular, and the incident light beam is a strip light beam;

[0047] Scanning the field of view includes: deflecting a plurality of light beams with different first deflection angles to the same second deflection angle, so as to complete scanning of a corresponding scanning subarea of ​​the field of view; deflecting each light beam with a first deflection angle in the plurality of light beams with different first deflection angles to a plurality of different second deflection angles, so as to complete scanning of a plurality of scanning subareas corresponding to the plurality of different second deflection angles;

[0048] The length of the light beam after being deflected by the second deflection angle is equal to the length of one direction of the scanning partition.

[0049] In some optional embodiments, the method further includes: changing the temperature of the second light deflection device to adjust the time for the second light deflection device to adjust the deflection angle.

[0050] An embodiment of the present invention provides a computer-readable storage medium, which stores program data and can be executed by a processor to implement the laser radar scanning method as described above.

[0051] The beneficial effects of the above technical solution provided by the embodiment of the present invention include at least:

[0052] The laser radar scanning method provided in an embodiment of the present invention adjusts the second deflection angle of the incident light beam deflected by the second light deflection device by controlling the voltage applied to the second light deflection device. However, since the light beam will be incident on the second light deflection device from multiple different first deflection angles after the first stage of deflection, and the light beams with different incident angles will have different diffraction efficiencies due to phase delay when passing through the second light deflection device, the embodiment of the present invention fine-tunes the actual working voltage applied to the second light deflection device according to the incident angle of the light beam incident on the second light deflection device, so that the working voltages corresponding to light beams with different incident angles of the same second deflection angle are different, so as to compensate for the phase delay caused by different incident angles, so that the diffraction efficiencies of light beams with different incident angles deflected by the second light deflection device to the same second deflection angle are the same, that is, the beam intensities of light beams with different incident angles after being deflected by the second light deflection device can be kept the same.

[0053] The length of the light beam used for deflection along the first direction is less than the length in the second direction. During the two-stage light deflection process, the light beam can naturally diverge to form a strip light beam whose length direction is along the second direction. The strip light beam is deflected in one dimension in the first direction (that is, the width direction of the light beam) by the first light deflection device, so that a second deflection angle corresponding to the second light deflection device can correspond to scanning an approximately rectangular scanning area. The second light deflection device performs two-dimensional deflection of the light beam at multiple second deflection angles in the first direction and the second direction respectively, and can correspond to scanning multiple scanning areas. Since the strip light beam can cover a larger field of view angle range in the length direction itself, after being deflected in the width direction by the first light deflection device, it can cover a field of view angle range of a certain width. On this basis, the second light deflection device only needs to deflect a smaller angle in two directions to cover the entire scanning area, thereby reducing the size and cost of the first light deflection device and the second light deflection device. In addition, the fewer deflection times can also shorten the switching time of the deflection angle, which is conducive to improving the detection frame rate. At the same time, since the strip light beam has a high degree of convergence in the width direction, the detection power can be relatively large when the light beam reaches a distant place, thereby making the detection distance longer, which can reach hundreds of meters, and the energy per unit light-receiving area is increased, and a better detection effect can be obtained; it can simultaneously meet the detection needs of long distances and large fields of view in application scenarios such as autonomous driving and vehicle navigation.

[0054] Furthermore, before the light beam enters the first optical deflection device, the light beam is collimated to meet the requirement of full deflection. For the long light beam emitted by the light source, in order to form a long scanning light beam at a distance, while taking into account the requirement of the first optical deflection device, such as the requirement that the aspect ratio should not be too large when the AOD crystal is cut, the long light beam emitted by the light source is strictly collimated in the width direction and not strictly collimated in the length direction, so as to reduce the aspect ratio and size of the light beam reaching the first optical deflection device, while meeting the requirement of alignment in the deflection direction. After the light beam is deflected by the first optical deflection device and the second optical deflection device, due to its high collimation in the width direction and small divergence angle, low collimation in the length direction and large divergence angle, the aspect ratio of the light beam reaching a distance is increased, and a long scanning light beam with an aspect ratio that meets the requirements can be formed. At the same time, due to the strict collimation in the first direction, the degree of convergence of the light beam in this direction is further improved. When the light beam reaches a distant place, the detection power can be greater, thereby making the detection distance longer, which can reach hundreds of meters, and the energy per unit light-receiving area is increased, and a better detection effect can be obtained; it can simultaneously meet the detection needs of long distance and large field of view in application scenarios such as autonomous driving and vehicle navigation.

[0055] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0056] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0058] Figure 1 It is a schematic diagram of the structure of the transmitting module in the first embodiment of the present invention.

[0059] Figure 2 This is one of the three-dimensional structural schematic diagrams of the transmitting module in the first embodiment of the present invention.

[0060] Figure 3 This is the second schematic diagram of the three-dimensional structure of the transmitting module in the first embodiment of the present invention.

[0061] Figure 4 Schematic diagram of the relationship between the incident angle and the operating voltage in the first embodiment of the present invention.

[0062] Figure 5 It is a structural schematic diagram of a light source in Embodiment 1 of the present invention.

[0063] Figure 6 A schematic diagram of a specific structure of the transmitting module in the first embodiment of the present invention.

[0064] Figure 7a Schematic diagram of the light path in the vertical direction in Embodiment 1 of the present invention.

[0065] Figure 7b Schematic diagram of the light path in the horizontal direction in the first embodiment of the present invention.

[0066] Figure 8a Schematic diagram of the optical path when the polarization expansion device includes two positive lenses in Embodiment 1 of the present invention.

[0067] Figure 8b Schematic diagram of the optical path when the polarization expansion device includes a positive lens and a negative lens in Embodiment 1 of the present invention.

[0068] Fig. 9 It is a schematic diagram of the composition structure of the transmitting module in the second embodiment of the present invention.

[0069] Fig.10aIt is a schematic diagram of the structure of the second light deflection device with electrode blocks on one side of the liquid crystal half-wave plate in the second embodiment of the present invention.

[0070] Fig.10b It is a schematic diagram of the structure of the second light deflection device with electrode blocks on both sides of the liquid crystal half-wave plate in the second embodiment of the present invention.

[0071] Fig.10c It is a schematic diagram of the structure of the second light deflection device with electrode blocks on one side of the liquid crystal half-wave plate and the liquid crystal polarization grating plate in the second embodiment of the present invention.

[0072] Fig.10d It is a schematic diagram of the structure of the second light deflection device with electrode blocks on both sides of the liquid crystal half-wave plate and the liquid crystal polarization grating plate in the second embodiment of the present invention.

[0073] Fig.11a It is a schematic structural diagram of a second light deflection device using a passive liquid crystal grating plate in the second embodiment of the present invention.

[0074] Fig.11b This is an example diagram of the relationship between the voltage applied to the second light deflection device and the deflection angle of the one-dimensional deflection in the second embodiment of the present invention.

[0075] Fig.11c This is an example diagram of the relationship between the voltage applied to the second light deflection device and the deflection angle of the two-dimensional deflection in the second embodiment of the present invention.

[0076] Fig.12 This is one of the exemplary diagrams of the scanning path of the light deflection unit in the second embodiment of the present invention.

[0077] Fig.13 This is a second example diagram of the scanning path of the light deflection unit in the second embodiment of the present invention.

[0078] Fig.14 This is the third example diagram of the scanning path of the light deflection unit in the second embodiment of the present invention.

[0079] Fig.15 This is a schematic diagram of the composition structure of the transmitting module in the third embodiment of the present invention.

[0080] Fig.16 Schematic diagram of the structure of the transmitting module in the fourth embodiment of the present invention.

[0081] Fig.17 It is a schematic diagram of the composition structure of the transmitting module in the fifth embodiment of the present invention.

[0082] Fig.18 Schematic diagram of the structure of the laser radar system in an embodiment of the present invention.

[0083] Fig.19 Flow chart of the laser radar scanning method in an embodiment of the present invention.

[0084] Fig. 20 Schematic diagram of the structure of a computer-readable storage medium in an embodiment of the present invention.

[0085] Description of reference numerals:

[0086] 1. Transmitting module; 2. Receiving module; 3. Processor; 4. Computer-readable storage medium;

[0087] 10. Laser radar system 100. First light deflection device; 200. Second light deflection device; 300. Light source; 400. Collimation device; 500. Deflection expansion device; 600. Control device;

[0088] 110, a first control unit; 128, a lens group; 1281, a first polarization expanding lens; 1282, a second polarization expanding lens;

[0089] 210, light deflection unit; 220, light deflection unit group; 230, second control unit; 240, temperature regulator;

[0090] 211, first electrode block; 2110, first electrode pair; 212, deflection partition; 2121, deflection sub-partition; 213, first whole electrode; 214, liquid crystal half-wave plate; 215, half-wave plate liquid crystal layer; 216, liquid crystal polarization grating plate; 217, first substrate; 218, second substrate; 2160, second electrode pair; 2161, third substrate; 2162, fourth substrate; 2163, second electrode block; 2164, grating liquid crystal layer; 2165, second whole electrode;

[0091] 310. Light-emitting unit. DETAILED DESCRIPTION

[0092] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0093] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention 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 therefore cannot be understood as limiting the invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0094] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0095] When liquid crystal beam deflection technology is used in laser radar, the cascaded liquid crystal polarization grating used can generally include a liquid crystal half-wave plate and a liquid crystal polarization grating. The liquid crystal half-wave plate uses the birefringence characteristics of liquid crystal to decompose the incident light beam into O light component and e light component with different refractive index according to the direction of the liquid crystal molecules. The O light component and the e light component produce phase delay during the propagation process due to the different refractive indices. If the phase delay is It is called a half-wave plate. Right-handed circularly polarized light becomes left-handed circularly polarized light after being incident vertically on the half-wave plate, and vice versa. When no voltage is applied to the liquid crystal half-wave plate, the liquid crystal is arranged parallel to the surface orientation layer, and the maximum phase delay is When voltage is applied, the liquid crystal molecules are deflected and the phase delay is , corresponding to a half-wave variation.

[0096] When a light beam is incident on a liquid crystal polarization grating, the incident angles of the light beams at different times may be different, and most of the light beams incident on the liquid crystal half-wave plate are non-vertically incident. If a working voltage corresponding to the vertical incidence of the light beam is applied to the liquid crystal half-wave plate, the circularly polarized light will become elliptically polarized light after being emitted, which will cause a decrease in diffraction efficiency when it is incident on the subsequent liquid crystal polarization grating.

[0097] In addition, AOD is currently used in combination with LCPG for secondary deflection, but a point light source is generally used. When the light beam generated by it reaches the distant scanning field of view area after secondary deflection, the scanning light beam formed is generally a circular or nearly circular light beam. In order to cover the long-distance and large-scale field of view area, the AOD is usually required to deflect at many angles in one direction and the LCPG is required to deflect at many angles in another direction, forming a scanning effect similar to a two-dimensional dot matrix. However, the more deflection angles, the larger the size of the AOD's acousto-optic crystal and the more layers of LCPG, resulting in large size and high cost of the AOD and LCPG.

[0098] In order to solve the existing problem of reduced diffraction efficiency caused by non-vertical incidence of the light beam on the liquid crystal polarization grating, reduce the size of the equipment and reduce the cost of the equipment, an embodiment of the present invention provides a transmitting module, a laser radar system and a corresponding laser radar scanning method.

[0099] Embodiment 1

[0100] Embodiment 1 of the present invention provides a transmitting module, the structure of which is shown in FIG. Figure 1 , Figure 2 and Figure 3 As shown, an optional structure of the emission module includes a light source 300 , a first light deflection device 100 , a second light deflection device 200 and a control device 600 .

[0101] The light source 300 is used to emit a light beam, wherein the length of the light beam along the first direction is shorter than the length of the light beam along the second direction.

[0102] The first light deflection device 100 is configured to deflect the light beam along a first direction by a plurality of first deflection angles and emit the light beam toward the second light deflection device 200 .

[0103] The second light deflection device 200 is configured to deflect the light beam deflected by the first light deflection device by multiple second deflection angles along the first direction and the second direction to project a scanning light beam; the length of the scanning light beam in the first direction is smaller than its length in the second direction.

[0104] The control device 600 is configured to control the voltage applied to the second optical deflection device to adjust the second deflection angle of the incident light beam by the second optical deflection device, and to fine-tune the corresponding applied working voltage according to the incident angle of the light beam incident on the second optical deflection device; wherein, for the same second deflection angle, different incident angles correspond to different working voltages.

[0105] In some optional embodiments, the control device 600 in the above-mentioned transmitting module can determine the operating voltage that makes the diffraction efficiency of the second light deflection device meet the requirements for the same second deflection angle of the second light deflection device based on the incident angle of the light beam incident on the second light deflection device. When the light beams with different first deflection angles deflected by the first light deflection device are incident on the second light deflection device, since the light beams with different first deflection angles have different incident positions and incident angles on the second light deflection device, the incident light beam has a certain phase delay after passing through the second light deflection device. In the process of the light beam incident on the second light deflection device and being deflected, the diffraction efficiency of the light beam is affected to different degrees. By fine-tuning the operating voltage of the second light deflection device, the difference in the diffraction efficiency of the second light deflection device for light beams incident at different angles can be compensated. The diffraction efficiency of the light beam is improved.

[0106] In the above-mentioned transmitting module, the control device 600 is also used to control the first light deflection device 100 and the second light deflection device 200 to deflect the light beam.

[0107] In the above-mentioned emission module, the first light deflection device 100 is, for example, but not limited to, a liquid crystal optical phased array (LCOPA) or an acousto-optic deflection device (AOD). The second light deflection device 200 is, for example, but not limited to, a liquid crystal polarization grating (LCPG). The liquid crystal polarization grating includes a liquid crystal half-wave plate and a liquid crystal polarization grating plate arranged in pairs. The liquid crystal half-wave plate and the liquid crystal polarization grating plate can be arranged in one pair, two pairs, or more than three pairs. More than two pairs of liquid crystal half-wave plates and liquid crystal polarization grating plates can be cascaded. After a voltage is applied to the liquid crystal half-wave plate, the light beam can be converted into polarized light. The liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating plate included in the liquid crystal polarization grating is, for example, but not limited to, a nematic phase liquid crystal or a blue phase liquid crystal.

[0108] The liquid crystal polarization grating plate is an active liquid crystal polarization grating plate or a passive liquid crystal polarization grating plate. The active liquid crystal polarization grating plate deflects the liquid crystal molecules by applying power, thereby achieving light beam deflection. The liquid crystal molecules in the passive liquid crystal polarization grating plate are already solidified in orientation and are not powered by themselves. By applying power to the liquid crystal half-wave plate, the liquid crystal electrically controlled wave plate modulates the polarization state of the incident light beam. The description of the embodiments of the present application is based on the passive liquid crystal polarization grating plate.

[0109] In some optional embodiments, the first light deflection device 100 adopts LCOPA, and the second light deflection device 200 adopts LCPG. The LCOPA is used to achieve fine adjustment of the light beam angle, and the LCPG is used to achieve coarse adjustment and amplification of the deflection angle.

[0110] In some optional embodiments, the first light deflection device 100 uses an AOD, and the second light deflection device 200 uses an LCPG. The AOD is used to finely adjust the light beam angle, and the LCPG is used to coarsely adjust and amplify the deflection angle. Since the AOD can achieve a microsecond response speed, a higher angular resolution can be obtained while deflecting the incident light beam. By using the subsequent LCPG to amplify the deflection angle, a coverage scan of the field of view can be achieved, which can better meet the scanning requirements of application scenarios that require instantaneous dynamic feedback, such as intelligent driving.

[0111] When the second light deflection device 200 adopts LCPG, the voltage applied to the second light deflection device 200 has a corresponding relationship with the second deflection angle of the incident light beam, that is, the same voltage value is applied to deflect the incident light beam to the same second deflection angle. However, the inventors have found that the non-vertical oblique incident light beam passing through the LCPG liquid crystal layer will change the ellipticity of the light beam when it is emitted, thereby affecting the diffraction efficiency of the emitted light beam. The larger the oblique incident angle, the smaller the ellipticity of the LCPG emitted light beam, and the lower the diffraction efficiency. That is, the light beam deflected by the same angle by LCPG will have a light intensity difference due to the different angles of the incident LCPG, which will eventually have a negative impact on the sensing effect. Therefore, in some embodiments, in order to compensate for the difference in diffraction efficiency of the liquid crystal polarization grating for light beams with different incident angles, the operating voltage of the liquid crystal polarization grating can be optimized by the control device 600. For the liquid crystal polarization grating, the same second deflection angle will be deflected through the light beam. When the incident angle of the light beam is different, the operating voltage of the liquid crystal polarization grating can be adjusted to correspond to different ones. The operating voltage applied by the control device 600 to the second light deflection device 200 includes the voltage applied to the liquid crystal half-wave plate and / or the voltage applied to the liquid crystal polarization grating plate. The incident angle of the light beam incident on the second light deflection device 200 is the angle difference between the incident direction of the light beam and the direction perpendicular to the incident surface of the second light deflection device. The operating voltage is positively correlated with the incident angle. The following description takes the adjustment of the operating voltage applied to the liquid crystal half-wave plate as an example. The case of adjusting the operating voltage applied to the liquid crystal polarization grating plate is similar and will not be repeated.

[0112] See also Figure 4 As shown, a schematic diagram of the relationship between the angle of the light beam incident on the liquid crystal polarization grating and the corresponding fine-tuning operating voltage is obtained through simulation and experiment. Taking the voltage of 2V applied to the second light deflection device corresponding to deflecting the light beam to a second deflection angle as an example, in the process of the incident angle of the light beam on the liquid crystal polarization grating changing from 0 to 5 degrees, the operating voltage is fine-tuned, and is adjusted to 2.06 when the incident angle is 5 degrees; in the process of the incident angle changing from 0 to -5 degrees, the operating voltage is fine-tuned, and is adjusted to 2.06 when the incident angle is -5 degrees.

[0113] The control device 600 is configured to determine a basic driving voltage to be applied to the second optical deflection device according to a second deflection angle of the incident light beam, and then determine a fine-tuning amplitude to be applied to the basic driving voltage according to the incidence of the incident light beam on the second optical deflection device, thereby obtaining an actual operating voltage applied to the second optical deflection device to compensate for the diffraction efficiency loss when the light beam is incident obliquely.

[0114] According to the incident angle when the light beam is incident on the liquid crystal half-wave plate, the thickness of the liquid crystal half-wave plate and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate, the phase delay of the liquid crystal half-wave plate corresponding to different incident angles can be determined; according to the total light intensity and circular polarization component of the incident light, the ellipticity of the light emitted by the liquid crystal half-wave plate can be determined; according to the relationship between the incident angle and the ellipticity, and the relationship between the ellipticity and the diffraction efficiency of the liquid crystal half-wave plate, the relationship between different incident angles and the diffraction efficiency can be determined; according to the phase delay of the liquid crystal half-wave plate corresponding to different incident angles, and the relationship between different incident angles and the diffraction efficiency, the relationship expression between the phase delay and the ellipticity is constructed, and the relationship expression is solved to determine the optimal operating voltage of the liquid crystal half-wave plate corresponding to different incident angles.

[0115] Based on this, for a given liquid crystal polarization grating, under the conditions of the total intensity of the incident light beam, the thickness of the liquid crystal half-wave plate, and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate, the relationship between the operating voltage of the liquid crystal half-wave plate and the incident angle can be determined, so that the control device can be configured to fine-tune the operating voltage applied to the liquid crystal half-wave plate according to the incident angle. Optionally, the control device can be configured to determine the optimal operating voltage applied to the liquid crystal half-wave plate corresponding to different incident angles according to the incident angle and total light intensity when the light beam is incident on the liquid crystal half-wave plate, the thickness of the liquid crystal half-wave plate, and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate.

[0116] Optionally, for the same second deflection angle of the second light deflection device, when the basic driving voltage is constant, the voltage fine-tuning amplitude is determined according to the incident angle of the light beam incident on the second light deflection device, and the operating voltage applied to the second light deflection device is adjusted to compensate for the diffraction efficiency loss caused by the phase delay caused by different incident angles, thereby improving the diffraction efficiency.

[0117] The above-mentioned emission module can change the phase delay and compensate for the diffraction efficiency loss caused by oblique incidence by calculating the optimal operating voltage of the liquid crystal half-wave plate when light is incident at a given angle and not vertically. Since the phase delay increases with the increase of the incident angle when the driving voltage is constant, the amplitude of the operating voltage of the liquid crystal half-wave plate can be increased accordingly. The voltage increase is approximately linearly related to the incident angle.

[0118] In order to meet the detection needs of long distance and large field of view and obtain better detection effect, the inventors of the present application have fully studied the deflection requirements of AOD and LCPG, as well as the deflection and propagation characteristics of light beams, and found that splicing edge emitting lasers (EEL) along the long axis direction can emit a strip light beam with a certain aspect ratio, which can cover a larger area after being deflected by two-stage optical deflection devices. At the same time, if the first-stage optical deflection device is deflected in the width direction of the strip light beam, it can cover a rectangular scanning area with a certain length and a certain width, so that the second-stage deflection device only needs to deflect a small number of angles in the length and width directions to cover a larger field of view spliced ​​by multiple scanning areas, thereby reducing the size and cost of AOD and LCPG while satisfying the requirement of scanning a larger field of view at a higher frame rate.

[0119] Based on this, the light source in the above-mentioned emission module is configured to emit a strip-shaped light beam, the length of the light beam along the first direction is smaller than the length in the second direction, the first deflection device and the second deflection device are configured to deflect the light beam, and during the two-stage light deflection process the light beam can naturally diverge to form a strip-shaped light beam whose own length direction is along the second direction. The strip light beam is deflected one-dimensionally in the first direction (that is, the width direction of the light beam) by the first light deflection device, so that a second deflection angle corresponding to the second light deflection device can correspond to scanning an approximately rectangular scanning area. The second light deflection device performs two-dimensional deflection of the light beam at multiple second deflection angles in the first direction and the second direction, respectively, and can correspond to scanning multiple scanning areas. Since the strip light beam itself can cover a larger field of view angle range in the length direction, it can cover a field of view angle range of a certain width after being deflected in its width direction by the first light deflection device. On this basis, the second light deflection device only needs to deflect a smaller angle in two directions to cover the entire scanning area, thereby reducing the size and cost of the first light deflection device and the second light deflection device. In addition, fewer deflection times can also shorten the switching time of the deflection angle, which is beneficial to improving the detection frame rate. At the same time, since the strip light beam has a high degree of convergence in the width direction, the detection power can be relatively large when the light beam reaches a distant place, thereby making the detection distance longer, which can reach hundreds of meters, and the energy per unit light-receiving area is increased, and a better detection effect can be obtained; it can simultaneously meet the detection needs of long distances and large fields of view in application scenarios such as autonomous driving and vehicle navigation.

[0120] In addition, considering that when the AOD deflects the light beam, the collimation of the light beam in the deflection direction is required to be large enough, combined with the shape characteristics of the strip light beam, before the light beam enters the AOD, the width direction of the light beam is strictly collimated, and the length direction is not strictly collimated, which can meet the requirements of the AOD to deflect the light beam in the width direction of the light beam. At the same time, the aspect ratio of the light beam can be relatively reduced when it reaches the AOD, taking into account the characteristics that the aspect ratio is not easy to be too large when the AOD crystal is cut, and further reducing the design size of the AOD. After the light beam is emitted from the AOD, due to the small divergence angle in the width direction and the large divergence angle in the length direction, after reaching a distance, it can form a strip scanning light beam, thereby taking into account the deflection requirements and crystal size of the AOD, and effectively forming a strip light beam, so that the LCPG can scan the entire field of view without deflecting many angles, thereby reducing the number of layers and thickness of the LCPG, and also improving the frame rate of scanning the entire field of view.

[0121] Based on this, the transmitting module provided in the first embodiment of the present invention is shown in FIG. Figure 6 As shown, an optional specific structure of the emission module may be based on the above-mentioned emission module structure and further include: a collimating device 400, configured to collimate the light beam before the light beam enters the first light deflection device 100; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction.

[0122] Optionally, in the above-mentioned emission module, the length of the scanning light beam emitted by the second light deflection device in the second direction is not less than the length of the light beam emitted by the light source in the second direction. Of course, optionally, the length of the scanning light beam emitted by the second light deflection device in the second direction may also be less than the length of the light beam emitted by the light source in the second direction.

[0123] The transmitting module provided in the first embodiment of the present invention is shown in FIG. Figure 6 As shown, an optional specific structure of the transmitting module, based on the above optional structure, further includes: a deflection expansion device 500, which is configured to amplify the deflection angle of the deflected light beam along the corresponding deflection direction by a preset multiple, and amplify the divergence angle of the light beam by a corresponding preset multiple to form a strip light beam. The preset multiple U of the deflection angle of the light beam amplified by the deflection expansion device 500 can be set as needed, and optionally, 1 <U<10。

[0124] The various optional structures of the above-mentioned transmitting module and the components involved therein are described in detail below in conjunction with the accompanying drawings.

[0125] In some embodiments, a light source control unit (not shown) can be used to control the light source 300 to emit light in a preset time sequence, and the shape of the generated light beam can be determined as needed, for example, the length along the first direction can be less than its length along the second direction, so that the first direction can be used as the width direction of the light beam, and the second direction can be used as the length direction of the light beam. The first direction is the deflection direction of the incident light beam deflected by the first light deflection device 100. In some embodiments, the first direction can be set to be perpendicular to the second direction, for example, the first direction can be a vertical direction, and the second direction can be a horizontal direction.

[0126] The above-mentioned transmitting module uses a strip light beam whose length along the first direction is shorter than that along the second direction, and combines the one-dimensional deflection of the first light deflection device 100 and the two-dimensional deflection of the second light deflection device 200 to form a long strip at the remote scanning position. Since the second light deflection device 200 adopts two-dimensional deflection, the size of the strip light beam can be shortened, and the field of view range can be scanned in different regions. This is because after the field of view range is divided into multiple scanning partitions, the strip light beam only needs to cover one scanning partition, and the length of the strip light beam only needs to be the length of one direction of the scanning partition. Compared with the scanning method of the prior art, the size of the light beam can be much smaller, thereby significantly reducing the crosstalk caused by highly reflective objects; on this basis, the length direction (second direction) of the strip light beam used is consistent with the length direction of the field of view range, so that the number of deflections of the second light deflection device 200 in the second direction can be reduced, thereby reducing the number of light deflection units required for the second light deflection device 200, so that the second light deflection device 200 can be made thinner and smaller in size. In addition, the size of the light beam used for scanning is reduced, and there is no need to expand the light beam specifically when forming the light beam. The light beam can be formed by freely diverging during the deflection process, thereby effectively avoiding the distortion of the light beam formed after expansion.

[0127] In the above-mentioned emission module, the light source can emit a light beam with a certain aspect ratio. The aspect ratio of the light beam when it enters the first light deflection device 100 can also be within a certain range to adapt to the light aperture size of the first light deflection device. After being deflected by the first light deflection device 100 and the second light deflection device 200, a scanning light beam with a certain aspect ratio is formed.

[0128] In some embodiments, the light beam emitted by the light source 300 is a strip light beam with an aspect ratio of 20:1 to 100:1; the light beam incident on the first light deflection device 100 has an aspect ratio of 3:1 to 1:2; and the scanning light beam is a strip light beam with an aspect ratio of 20:1 to 80:1. Through the light beam with an aspect ratio within a certain range, the two light deflection devices deflect, optionally combined with collimation and / or expansion, to form a strip scanning light beam with a certain aspect ratio, so that the scanning light beam can cover a directional length of a scanning sub-area within the field of view, thereby realizing the field of view range. Area scanning.

[0129] Optionally, the aspect ratio of the light beam emitted by the light source 300 is 50:1; the aspect ratio of the light beam incident to the first light deflection device 100 is 5:2; the aspect ratio of the scanning light beam is 75:1; or optionally, the aspect ratio of the light beam emitted by the light source 300 is 50:1; the aspect ratio of the light beam incident to the first light deflection device 100 is 5:2; the aspect ratio of the scanning light beam is 25:1.

[0130] The light source 300 includes a plurality of light emitting units 310 spliced ​​together to emit a light beam with a required aspect ratio. In practical applications, the splicing method can be selected as needed, for example, splicing along different directions according to the aspect ratio requirements, such as Figure 5 In the figure, multiple light-emitting units 310 are spliced ​​into a row along the length direction thereof. Optionally, they can also be spliced ​​into two or more rows, that is, multiple light-emitting units 310 are spliced ​​into a row along the length direction thereof, and at the same time, each row is spliced ​​along the width direction of the light-emitting units 310 to form two or more rows. A light source control unit (not shown in the figure) can be used to control the light source to emit light according to a preset time sequence, and the length of the generated light beam along the first direction is less than its length along the second direction, so that the first direction is the width direction of the light beam, and the second direction is the length direction of the light beam. The first direction is the deflection direction of the incident light beam deflected by the first light deflection device 100. In some embodiments, the first direction can be set to be perpendicular to the second direction, for example, the first direction can be a vertical direction, and the second direction can be a horizontal direction; optionally, the first direction can be a horizontal direction, and the second direction can be a vertical direction.

[0131] The light emitting unit 310 is, for example but not limited to, at least one of the light emitting structures in the form of a vertical cavity surface emitting laser (VCSEL, which can also be translated as a vertical resonant cavity surface emitting laser), an edge emitting laser (EEL), a light emitting diode (LED), a laser diode (LD), a fiber laser, etc. Among them, the edge emitting laser can be a Fabry Perot (FP) laser, a distributed feedback (DFB) laser, an electro-absorption modulated laser (EML), etc., and this application does not limit this. Taking the light emitting unit 310 as an EEL as an example, the light beam emitted by the EEL itself is a narrow and long light beam. The EEL light emitting unit 310 spliced ​​along the long axis direction of the emitted light beam can emit a light beam that meets the preset aspect ratio requirements.

[0132] The first optical deflection device 100 is used as a fine deflection device, and the second optical deflection device 200 is used as a coarse deflection device to deflect the light beam. That is, the first optical deflection device 100 deflects the light beam in sequence at a finer angle interval within a smaller deflection angle range, and the first optical deflection device 100 deflects the light beam in sequence at a relatively small angle; the second optical deflection device 200 deflects the light beam deflected by the first optical deflection device 100 in sequence at a coarser angle interval within a larger deflection angle range, that is, the second optical deflection device 200 deflects the light beam deflected by the first optical deflection device 100 in a relatively large angle in a time-sharing manner, and finally a comprehensive scan of the field of view can be achieved. The fine deflection device and the coarse deflection device are combined, and the advantages of the fine deflection device with fast response speed and high number of distinguishable points are utilized to achieve detailed scanning within a small angle range. By utilizing the advantages of the coarse deflection device with high diffraction efficiency and large deflection angle, the scanning range can be expanded to cover a wide field of view when the number of deflection angles of the coarse deflection device is small. In some embodiments, the second optical deflection device 200 is configured to perform a secondary deflection on the light beam deflected by the first optical deflection device 100 to form a light beam that scans the field of view. In this case, the light beam can be finely deflected to multiple first deflection angles near a second deflection angle coarsely deflected by the second optical deflection device 200 through the first optical deflection device 100, and finally quasi-continuous fine scanning can be achieved within a larger deflection angle range of the second optical deflection device 200 with the deflection accuracy of the first optical deflection device 100. The second optical deflection device 200 can deflect the light beam to multiple different second deflection angles in the first direction and the second direction. That is, the first optical deflection device 100 can deflect the light beam in one dimension, and the second optical deflection device 200 can deflect the light beam in two dimensions, which can reduce the number of deflection angles of the second optical deflection device 200 and make the second optical deflection device 200 thinner. It is understandable that in some other embodiments, according to the requirements of actual applications, the first light deflection device 100 can also be configured to perform secondary deflection on the light beam deflected by the second light deflection device 200, and the present application does not limit this.

[0133] In some embodiments, the first optical deflection device 100 can optionally deflect the light beam periodically or non-periodically, or can deflect in a certain order in a time-sharing manner or deflect more than one light beam at the same time. Taking the periodic time-sharing deflection as an example, the first optical deflection device 100 is configured to deflect the incident light beam to multiple different first deflection angles in a preset order in a time-sharing manner within a deflection period; the deflection period is the time required for the first optical deflection device 100 to deflect the incident light beam to all multiple different first deflection angles, or the deflection period is the time required for the first optical deflection device 100 to deflect the incident light beam to a specified portion of the first deflection angles.

[0134] The first light deflection device 100 is configured to deflect the incident light beam in a first direction in sequence to a plurality of different first deflection angles; the first light deflection device 100 can deflect the light beam at a plurality of first deflection angles within a preset angle range, that is, the control device 600 can control the first light deflection device 100 to generate a plurality of incident light beams at different first deflection angles within a preset angle range and at a preset deflection time interval, and project the light beams onto the second light deflection device 200. For example, within the range of -1.5 to +1.5 degrees, the light beam is deflected to a plurality of first deflection angles with a certain interval, and the first deflection angle is an angle sequence, for example: -1.5, -1.0, -0.5, 0, 0.5, 1, 1.5, etc., and the angle interval can be set as needed. In some embodiments, the first light deflection device 100 can repeatedly deflect the light beam to all or part of the plurality of first deflection angles according to a plurality of preset deflection cycles. The deflection cycle refers to the time required for the first light deflection device 100 to deflect a plurality of first deflection angles within a preset angle range. It can also be said that the deflection period refers to the time required for the first optical deflection device 100 to sequentially deflect the light beam to all or part of the preset first deflection angles among a plurality of first deflection angles. It should be understood that the duration of any two different deflection periods can be set to be the same or different; within any two different deflection periods, the number and order of the first deflection angles at which the first optical deflection device 100 deflects the light beam can be set to be the same or different. Within one of the deflection periods, the first optical deflection device 100 may also repeatedly deflect the light beam to one or more of the first deflection angles twice or more. After completing the deflection of a deflection period, the first optical deflection device 100 may enter the next deflection period and continue to perform a new round of deflection on the light beam according to the number and order of the correspondingly set first deflection angles.

[0135] The first light deflection device 100 can be configured to use the narrower width direction of the incident light beam as the scanning direction, and deflect the incident light beam by a plurality of different first deflection angles to project it to different positions on the second light deflection device 200. The second light deflection device 200 deflects the deflected light beam incident at different first deflection angles by the same second deflection angle to complete the scanning of a corresponding scanning subarea within the field of view; and by analogy, the second light deflection device 200 deflects the light beam of each first deflection angle in the light beam incident at different first deflection angles by a plurality of second deflection angles to complete the scanning of a plurality of scanning subareas corresponding to the plurality of different second deflection angles.

[0136] Optionally, the first optical deflection device 100 deflects the light beam at multiple first deflection angles in one deflection cycle, and the second optical deflection device 200 deflects the light beams at multiple first deflection angles deflected by the first optical deflection device 100 at the same or different second deflection angles in the deflection cycle. Optionally, the second optical deflection device 200 deflects the light beams deflected by the first optical deflection device 100 at one, two or more second deflection angles in the deflection cycle.

[0137] It can be understood that in some embodiments, when the scanning of the entire field of view is completed, the first light deflection device 100 and the second light deflection device 200 can be configured to deflect the light beam at different first deflection angles and in what order, so as to first complete the scanning of one scanning area, then scan the next scanning area, and so on, until all scanning areas are scanned. That is, the second light deflection device 200 can deflect the deflected light beams incident at different first deflection angles to the same second deflection angle within one deflection cycle, so as to complete the scanning of a corresponding scanning partition in one deflection cycle, thereby completing the scanning of multiple different scanning partitions correspondingly after multiple deflection cycles.

[0138] See also Figure 2 As shown, the entire field of view can be divided into multiple scanning partitions. Figure 2 In the figure, 16 scanning subareas are taken as an example, corresponding to 16 grids in the figure. The second light deflection device 200 deflects 2 second deflection angles in the first direction and 8 second deflection angles in the second direction, which can achieve Figure 2 The scanning of the 16 scanning partitions shown in the figure corresponds to each scanning partition and a second deflection angle, that is, after the multiple first deflection angles deflected by the first optical deflection device 100 are deflected by the same second deflection angle by the second optical deflection device 200, they can cover a scanning partition. Among them, the scanning partition is rectangular, and the length of the strip light beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition. During actual scanning, in the first deflection cycle, the multiple light beams with the first deflection angles deflected by the first optical deflection device 100 can be deflected by the first second deflection angle to complete the scanning of the scanning partition corresponding to the first square of the first row; in the second deflection cycle, the multiple light beams with the first deflection angles deflected by the first optical deflection device 100 can be deflected by the second second deflection angle to complete the scanning of the scanning partition corresponding to the second square of the first row; and so on, in the fourth deflection cycle, the multiple light beams with the first deflection angles deflected by the first optical deflection device 100 can be deflected by the fourth second deflection angle, as shown in FIG. Figure 2 As shown, the scanning of the scanning partition corresponding to the fourth square in the first row is completed; thus, after 16 deflection cycles, the scanning of all the scanning partitions corresponding to the 16 squares is completed.

[0139] In some other embodiments, the second light deflection device 200 can deflect the deflected light beam incident at different first deflection angles to two or more different second deflection angles in one deflection cycle; in this case, in one deflection cycle, the scanning is no longer concentrated on one corresponding scanning subarea, but the scanning is performed in a jump manner on different positions in two or more different scanning subareas along the deflection direction of the first light deflection device 100; in this way, the scanning of all scanning subareas can be completed after a plurality of deflection cycles. For example, in this embodiment, in one deflection cycle, the light beams formed by the first light deflection device 100 and the second light deflection device 200 correspondingly scan the scanning subareas corresponding to the different second deflection angles, and the scanned positions are spaced far apart from each other, which can reduce the mutual crosstalk between two adjacent scans.

[0140] See also Figure 3 As shown, the entire field of view can be divided into multiple scanning partitions, and the number of scanning partitions is 16, corresponding to the 16 grids in the figure. In one deflection cycle, the second optical deflection device 200 can deflect the multiple light beams of the first deflection angle deflected by the first optical deflection device 100 to different second deflection angles, so as to alternately scan different scanning partitions. For example, in the first deflection cycle, the second optical deflection device 200 deflects the first light beam of the first first deflection angle to the first second deflection angle, and scans a small strip area in the first square of the first row; deflects the second light beam of the second first deflection angle to the second second deflection angle, and scans a small strip area in the second square of the first row; .... In the second deflection cycle, the second optical deflection device 200 deflects the first light beam of the first first deflection angle to the first second deflection angle, and scans a small strip area in the second square of the first row; deflects the second light beam of the second first deflection angle to the second second deflection angle, and scans a small strip area in the third square of the first row; .... By analogy, the scanning area corresponding to each square is cross-scanned, and after multiple deflection cycles, the scanning of all scanning partitions corresponding to all squares is completed.

[0141] Compared with the case of scanning with a circular or nearly circular spot, using a long strip beam to scan the field of view and making the AOD deflect the beam in the width direction of the beam can greatly reduce the number of angles of LCPG deflection in the first direction and the second direction, for example Figure 2 and Figure 3 As shown, the deflection is 16 angles, 8 angles in the horizontal direction, and 2 angles in the vertical direction. The number of angles of LCPG deflection is related to the number of layers it contains (i.e., the number of light deflection units in the second light deflection device 200). Therefore, the number of layers of LCPG can also be reduced. For example, when the deflection is 16 angles, four layers of LCPG are sufficient, and LCPG can be made thinner and smaller in size.

[0142] In some embodiments, a specific structural example of the above-mentioned transmitting module is shown in Figure 6 As shown, a collimating device 400 is also included, which is configured to collimate the light beam before the light beam enters the first light deflection device 100; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction.

[0143] The collimation device 400 can collimate the light beam emitted by the light source 300 in the first direction and the second direction perpendicular to each other, and the collimated light beam is then incident on the first light deflection device 100. Among them, the collimation requirement in the first direction is higher than the collimation requirement in the second direction, that is, the divergence angle of the collimated light beam in the first direction is smaller than the divergence angle in the second direction. Optionally, the divergence angle of the collimated light beam after collimation in the first direction is less than 1 / 10 of the divergence angle after collimation in the second direction. When the collimation device 400 collimates the light beam, its collimation can be measured by the size of the divergence angle. Based on the general law of light propagation, in a certain direction, the higher the collimation, the smaller the divergence angle of the light beam, and the larger the size of the light beam in that direction. Conversely, in a certain direction, the lower the collimation, the larger the divergence angle of the light beam, and the smaller the size of the light beam in that direction. The first light deflection device 100, taking the AOD device as an example, has a light aperture aspect ratio that is usually smaller than the strip light beam emitted after the light sources are spliced. In order to fully deflect the light beam, the collimation requirement in the deflection direction is high and the light beam divergence angle is small, while the collimation requirement in the non-deflection direction is low and the light beam divergence angle is large. Therefore, a suitable collimation device can be designed to strictly collimate the light beam only in the deflection direction of the first light deflection device 100, and no strict collimation is required in other directions. The collimated light beam can meet the deflection requirement of the AOD device in the deflection direction, thereby improving the efficiency of the light beam deflection through the AOD device. The collimated light beam can also diffuse naturally with a larger divergence angle in the non-deflection direction, so as to facilitate the subsequent formation of a strip light beam.

[0144] The collimating device 400 may include at least one collimating lens. Optionally, in order to collimate the light beam according to the collimation requirement, the positional relationship between the collimating device 400 and the light source 300 may be set according to the light beam collimation requirement, and an optional setting method is: the light source 300 is set on the focal plane of the collimating lens; when the collimating device 400 includes at least two collimating lenses, the focal planes of at least two collimating lenses overlap.

[0145] Optionally, the collimating device 400 includes a first cylindrical lens and a second cylindrical lens, wherein the first cylindrical lens is configured to collimate the light beam along a first direction, and the second cylindrical lens is configured to collimate the light beam along a second direction. In this case, the first cylindrical lens and the second cylindrical lens may select lenses with different focal lengths to achieve outgoing light beams with different collimation degrees in different directions, wherein the cylindrical lens with a smaller focal length is arranged at a position closer to the light source, and the cylindrical lens with a larger focal length is arranged at a position relatively far from the light source, and the focal planes of the two cylindrical lenses may overlap, and the light source is arranged at the focal plane.

[0146] Optionally, the collimating device 400 includes a spherical lens, which is configured to collimate the light beam along the first direction and the second direction. In this case, the light beam is collimated in two directions by the spherical lens, and the focal length of the spherical lens is selected according to the collimation requirements in the two directions to meet the collimation requirements in the two directions. Optionally, at least in the direction with high collimation requirements, the collimation of the collimated light beam can reach the required collimation.

[0147] Optionally, the collimating device 400 includes a cylindrical lens and a spherical lens, wherein the cylindrical lens is configured to collimate the light beam along a first direction, and the spherical lens is configured to collimate the light beam along a first direction and a second direction at the same time. In this case, the cylindrical lens and the spherical lens are used to collimate the light beam simultaneously in the direction where the collimation requirement is high, and the spherical lens is used to collimate the light beam simultaneously in the direction where the collimation requirement is low, so as to obtain output light beams with different collimations in different directions. Optionally, the focal planes of the cylindrical lens and the spherical lens may overlap, and the light source is arranged at the focal plane.

[0148] In some embodiments, the collimator 400 is configured to collimate a light beam with an aspect ratio of A into a light beam with an aspect ratio of B, and A>B; the first light deflector 100 and the second light deflector 200 are configured to deflect the light beam with an aspect ratio of B and project a light beam with an aspect ratio of C, and C>B. That is, if the light beam incident on the collimator 400 has an aspect ratio of A, after being collimated by the collimator 400, the aspect ratio of the light beam emitted from the collimator or incident on the first light deflector will become smaller and become B. After the primary deflection by the first light deflector and the secondary deflection by the second light deflector, the aspect ratio of the scanning light beam projected to a distance will increase again and become C, so as to form a long strip of light beam.

[0149] The focal length of the collimating lens in the collimating device can be selected as needed, for example, according to the divergence angle and size of the light beam after collimation and the divergence angle and size of the light beam before collimation. Figure 7a The vertical optical path and Figure 7b The horizontal optical path shown uses two cylindrical lenses as an example.

[0150] In the vertical direction: the light width V1 of the light source in the vertical direction (first direction), the divergence angle θ1 of the light source in the vertical direction (first direction), collimated by the cylindrical lens with a focal length of F2, the waist diameter V2 in the first direction when the light beam is incident on the first light deflection device 100, the divergence angle θ2 in the first direction when the light beam is incident on the first light deflection device 100, and the focal length F2 of the collimating lens that collimates the light beam along the first direction satisfy the following relationship: θ2= V1 / F2, θ2 V2=θ1 V1. The interval between the optical center of the cylindrical lens with a focal length of F2 and the light source can be selected as the focal length F2.

[0151] In the horizontal direction: the light length H1 of the light source in the horizontal direction (second direction), the divergence angle θ1 of the light source in the horizontal direction (second direction), collimated by the cylindrical lens with a focal length of F1, the beam waist diameter H2 in the second direction when the light beam is incident on the first light deflection device 100, the divergence angle θ2 in the second direction when the light beam is incident on the first light deflection device 100, and the focal length F1 of the collimating lens that collimates the light beam in the second direction satisfy the following relationship: θ2 = H1 / F1, θ2 H2 = θ1 H1. The interval between the optical center of the cylindrical lens with a focal length of F1 and the light source can be selected as the focal length F1.

[0152] In some embodiments, when a bar-shaped light source is generally selected, H1>>V1 may be selected. Therefore, by selecting appropriate lens focal lengths F1 and F2, θ2>>θ2 can be achieved, so that the light spot will appear as a long strip in the far field after passing through the subsequent spherical lens.

[0153] In some embodiments, see Figure 6 As shown, the above-mentioned transmitting module also includes a deflection expansion device 500, which is configured to amplify the deflection angle of the deflected light beam along the corresponding deflection direction by a preset multiple, and amplify the divergence angle of the light beam by a corresponding preset multiple to form a strip light beam.

[0154] Optionally, the polarization expanding lens is configured to magnify the deflection angle of the light beam deflected by the first optical deflection device 100 or the second optical deflection device 200 in at least one of the first direction and the second direction by a preset multiple. The polarization expanding device 500 can also magnify the divergence angle of the light beam deflected by the first optical deflection device 100 or the second optical deflection device 200 in the corresponding deflection direction by a preset multiple, and the divergence angle magnification factor is the same as the deflection angle magnification factor of the deflected light beam in the deflection direction. In other words, the polarization expanding device 500 can be disposed between the first optical deflection device 100 and the second optical deflection device 200, and is configured to magnify the deflection angle of the light beam deflected by the first optical deflection device 100 by a preset multiple before it is incident on the second optical deflection device 200. Figure 5The deflection expansion device 500 can also be arranged on the light output side of the second optical deflection device 200, and is configured to amplify the deflection angle of the light beam deflected by the second optical deflection device 200 by a preset multiple.

[0155] The polarization expansion device 500 may include at least one polarization expansion lens. The polarization expansion lens is a single lens or a combination of two or more lenses; the polarization expansion lens may include at least one or any combination of a cylindrical lens, a spherical lens, a super lens, and a Fresnel lens; when the polarization expansion lens includes a combination of two or more lenses, the combination of the two or more lenses may be regarded as one lens.

[0156] The at least one polarization expanding lens is configured to magnify the deflection angle of the light beam deflected by the first optical deflection device 100 in at least one of the first direction and the second direction perpendicular to each other by a preset multiple. The polarization expanding device 500 can also magnify the divergence angle of the light beam deflected by the first optical deflection device 100 in the corresponding deflection direction by a preset multiple, and the divergence angle magnification is the same as the deflection angle magnification of the deflected light beam in the deflection direction. The focal length of the polarization expanding lens is set according to the magnification of the deflection angle. When the polarization expanding device 500 includes two polarization expanding lenses, one side focus of one polarization expanding lens coincides with one side focus of the other polarization expanding lens, and the magnification is the ratio of the focal lengths of the two polarization expanding lenses.

[0157] The positional relationship between the first light deflection device 100, the second light deflection device 200 and the polarization expanding device 500 can be designed according to the parameters of each device. Optionally, the distance between the first polarization expanding lens in the first light deflection device 100 and the polarization expanding device 500 is the focal length of the first polarization expanding lens; the distance between two adjacent polarization expanding lenses is the sum of the focal lengths of the two adjacent polarization expanding lenses. Thus, the light beam deflected by the first light deflection device 100 can converge at the rear focus after passing through the polarization expanding lens and then further diverge, so that the deflection angle of the light beam can be expanded to the required angle within a shorter distance, so that the second light deflection device 200 can be set closer to the first light deflection device 100.

[0158] In some embodiments, the polarization expansion device includes two polarization expansion lenses, both polarization expansion lenses are single lenses, both polarization expansion lenses are combinations of two or more lenses, or one of the two polarization expansion lenses is a single lens and the other is a combination of two or more lenses.

[0159] Optionally, the two polarization expanding lenses included in the polarization expanding device 500 are both a combination of two or more lenses. An optional setting is: the polarization expanding device 500 includes at least one of the first cylindrical lens group and the second cylindrical lens group; the first cylindrical lens group includes the first polarization expanding cylindrical lens and the second polarization expanding cylindrical lens, which are configured to magnify the deflection angle of the light beam deflected by the first light deflection device in the first direction by a preset multiple, and the preset multiple is the ratio of the focal length of the first polarization expanding cylindrical lens to the focal length of the second polarization expanding cylindrical lens; the second cylindrical lens group includes the third polarization expanding cylindrical lens and the fourth polarization expanding cylindrical lens, which are configured to magnify the deflection angle of the light beam deflected by the first light deflection device in the second direction by a preset multiple, and the preset multiple is the ratio of the focal length of the third polarization expanding cylindrical lens to the focal length of the fourth polarization expanding cylindrical lens. In specific applications, cylindrical lens groups can be set as needed. For example, a first cylindrical lens group can be set alone to expand the light beam in a first direction; a second cylindrical lens group can be set alone to expand the light beam in a second direction; or a first cylindrical lens group and a second cylindrical lens group can be set at the same time to expand the light beam in the first direction and the second direction at the same time.

[0160] Optionally, the two polarization expanding lenses included in the polarization expanding device 500 are both single lenses. An optional setting is: the polarization expanding device 500 includes a first polarization expanding spherical lens and a second polarization expanding spherical lens, which are configured to magnify the deflection angle of the light beam deflected by the first light deflection device in the first direction and the second direction by a preset multiple, and the preset multiple is the ratio of the focal length of the first polarization expanding spherical lens to the focal length of the second polarization expanding spherical lens. When the polarization expanding lens uses a spherical lens, the number of lenses used can be reduced.

[0161] In some embodiments, see Figure 8a and Figure 8b As shown, the polarization expansion device 500 includes, for example, a first polarization expansion lens 1281 and a second polarization expansion lens 1282. The first polarization expansion lens 1281 and the second polarization expansion lens 1282 are arranged in sequence along the propagation direction of the light beam, and the focus of one side of the first polarization expansion lens 1281 and the focus of one side of the second polarization expansion lens 1282 are arranged to overlap with each other in the section between the first polarization expansion lens 1281 and the second polarization expansion lens 1282. That is, the light beam deflected by the first optical deflection device or the second optical deflection device is first converged by the first polarization expansion lens 1281 on the focal plane of the second polarization expansion lens 1282, and then deflected by the second polarization expansion lens 1282 to achieve the amplification of the deflection angle.

[0162] For example, in Figure 8aIn the illustrated embodiment, both the first polarization expanding lens 1281 and the second polarization expanding lens 1282 have positive optical power. If the focal length of the first polarization expanding lens 1281 is F1 and the focal length of the second lens is F2, then the magnification of the beam deflection angle by the polarization expanding device 500 is M=F1 / F2, that is, the angle of the beam deviating from the center direction of the field of view range after being deflected by the first optical deflection device or the second optical deflection device before entering the polarization expanding device 500 will be magnified M times after passing through the polarization expanding device 500.

[0163] For example, in Figure 8b In the illustrated embodiment, the first polarization expander lens 1281 has a positive optical focal length, and the second polarization expander lens 1282 has a negative optical focal length. If the focal length of the first polarization expander lens 1281 is F1, and the focal length of the second lens is F2, then the magnification factor of the light beam deflection angle by the polarization expander device 500 is M=F1 / F2, that is, the angle of the light beam deviating from the center direction of the field of view range after being deflected by the first optical deflection device or the second optical deflection device before entering the polarization expander device 500 will be magnified M times after passing through the polarization expander device 500.

[0164] It should be understood that the first polarization expanding lens 1281 can be a single lens or a lens group including multiple lenses. Similarly, the second polarization expanding lens 1282 can be a single lens or a lens group including multiple lenses.

[0165] It should be understood that the first polarization expanding lens 1281 and the second polarization expanding lens 1282 can both be spherical mirrors that are rotationally symmetric about the optical axis, and are configured to magnify the deflection angles of the passing light beam in each direction by the same multiple. For example, the first polarization expanding lens 1281 and the second polarization expanding lens 1282 magnify the deflection angles of the passing light beam in the first direction and the second direction by M times, and the first direction is perpendicular to the second direction.

[0166] Taking the example of the polarization expander 500 being arranged between the first optical deflection device 100 and the second optical deflection device 200, the first optical deflection device 100 is configured to deflect the light beam by multiple first deflection angles in a deflection period, and project the deflected light beam to the polarization expander 500; the polarization expander 500 is configured to amplify the deflection angle of the deflected light beam in the corresponding deflection direction by a preset multiple, and project the deflected light beam to the corresponding position of the second optical deflection device 200; the second optical deflection device 200 is configured to deflect the light beam by a preset second deflection angle within the deflection period to project a scanning light beam. With such a setting, when the distance between the two-stage optical deflection devices is reduced, after the light beam is deflected by the first optical deflection device 100, the light spot irradiated to the second optical deflection device 200 will become smaller as the distance decreases, and the size of the second optical deflection device 200 can also be smaller, thereby further reducing the overall structure of the transmitting module, which can meet the requirements for miniaturization of vehicle-mounted laser radars in application scenarios such as intelligent driving; in addition, through the cooperation of the two-stage optical deflection device and the expansion device, continuous and fine adjustment of the light beam deflection angle can be achieved within a larger angle range, and at the same time, the angle interval of the light beam deflected by the first optical deflection device can be made smaller, thereby achieving more refined light scanning and improving the coverage effect of the laser radar light scanning.

[0167] Taking the case where the deflection expander 500 is arranged on the light-emitting side of the second light deflection device 200 as an example, the first light deflection device 100 is configured to deflect the light beam by multiple first deflection angles in a deflection cycle, and project the deflected light beam to the corresponding position of the second light deflection device 200; the second light deflection device 200 is configured to deflect the light beam by a preset second deflection angle in the deflection cycle; the deflection expander 500 is configured to amplify the deflection angle of the light beam deflected by the second light deflection device 200 in the corresponding deflection direction by a preset multiple to project a scanning light beam. Such a setting can increase the deflection angle of the light beam deflected by the second light deflection device, and can also miniaturize the transmitting module.

[0168] In the above two configurations, the deflection expander 500 is disposed between the first optical deflection device 100 and the second optical deflection device 200, which can increase the deflection angle of the light beam deflected by the first optical deflection device. Through the deflection expander 500, the light beams with adjacent deflection angles deflected by the first optical deflection device can be distinguished within the shortest possible distance, thereby shortening the distance between the second optical deflection device and the first optical deflection device, and making the overall structure of the transmitting module smaller. The deflection expander 500 is disposed on the light-emitting side of the second optical deflection device 200, which can increase the deflection angle of the light beam deflected by the second optical deflection device. Through the deflection expander 500, the light beams with adjacent deflection angles deflected by the second optical deflection device can be distinguished within the shortest possible distance, thereby reducing the deflection angle requirement for the first optical deflection device when deflecting the light beam, thereby shortening the distance between the second optical deflection device and the first optical deflection device, and making the overall structure of the transmitting module smaller. In the above two settings, after the distance between the two-stage optical deflection devices is reduced, after the light beam is deflected by the first optical deflection device 100, the light spot irradiated to the second optical deflection device 200 will become smaller as the distance decreases, and the size of the second optical deflection device 200 can also be smaller, thereby further reducing the overall structure of the transmitting module, which can meet the requirements for miniaturization of vehicle-mounted LiDAR in application scenarios such as intelligent driving; in addition, through the cooperation of the two-stage optical deflection device and the deflection expansion device, the continuous and fine adjustment of the light beam deflection angle can be achieved within a larger angle range, and at the same time, the angle interval of the light beam deflected by the first optical deflection device can be made smaller, thereby achieving more refined light scanning and improving the coverage effect of the LiDAR light scanning.

[0169] In the above-mentioned transmitting module, the deflection accuracy of the first light deflection device 100 on the light beam is higher than the deflection accuracy of the second light deflection device 200 on the light beam.

[0170] In some embodiments, the deflection speed of the light beam by the first light deflection device 100 is higher than the deflection speed of the light beam by the second light deflection device 200. The first light deflection device 100 performs multiple fine deflections of the first deflection angle at each second deflection angle of the coarse deflection of the second light deflection device 200. It can be seen that the number of fine deflections of the first light deflection device 100 in one scan of the entire field of view is several times that of the coarse deflection of the second light deflection device 200. Therefore, the light deflection time required for scanning can be reduced by using the first light deflection device 100 with a faster deflection speed to perform more fine deflections.

[0171] In some embodiments, the first light deflection device 100 is configured to deflect the incident light beam at a plurality of different first deflection angles, wherein the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the incident light beam along the deflection direction, so that the edges of the two adjacent light beams deflected by the first light deflection device 100 can overlap slightly, thereby ensuring that the scanning area is fully covered and no scanning is missed.

[0172] In some embodiments, the divergence angle of the strip light beam formed by the deflection expansion device 500 along the second direction is greater than or equal to the angle interval between two adjacent second deflection angles along the second direction of the second light deflection device 200. Thus, the edges of two adjacent light beams deflected by two adjacent second deflection angles in the second direction can overlap slightly, thereby ensuring that the scanning area is fully covered and no scanning is missed.

[0173] In some embodiments, the deflection angle range of the light beam deflected along the first direction by the first light deflection device 100 is greater than or equal to the angle interval between two adjacent second deflection angles along the first direction by the second light deflection device 200. Thus, the edges of the scanning area covered by the light beams deflected by the two adjacent second deflection angles in the first direction can overlap slightly, thereby ensuring that the scanning area is fully covered without missing any scans.

[0174] In some embodiments, the above-mentioned emission module, when the light beam emitted by the light source is linearly polarized light, further includes a 1 / 2 wave plate disposed between the collimating device 400 and the first light deflecting device 100, for changing the polarization direction of the light beam. The optical axis of the 1 / 2 wave plate is perpendicular to the direction of the light beam emitted by the collimating device 400, and the electric field direction of the linearly polarized light forms an angle of 45 degrees with the fast axis of the 1 / 2 wave plate, or the electric field direction of the linearly polarized light forms an angle of 45 degrees with the slow axis of the 1 / 2 wave plate.

[0175] In the scheme in which the first light deflection device 100 is combined with the second light deflection device 200 to deflect the light beam, in some cases, the polarization direction of the light beam needs to be rotated. In this case, it can be achieved by setting a 1 / 2 wave plate between the collimating device 400 and the first light deflection device 100. Taking the use of an EEL light source as an example, the light beam emitted by the EEL is generally approximately TE mode linear polarized light, and the electric field direction is parallel to the slow axis direction, for example, in the horizontal direction in this application. On the other hand, when designing the first light deflection device 100, it is generally required that the polarization direction of the incident light is parallel to the ultrasonic direction, for example, in the vertical direction in this application. In this case, the polarization direction needs to be rotated 90 degrees before the light beam is incident, for example, in this application, and the polarization direction rotation can be achieved by setting a 1 / 2 wave plate for rotating the polarization direction. The optical axis of the 1 / 2 wave plate is perpendicular to the direction of the emitted light beam, and the electric field direction of the linearly polarized light is at a 45-degree angle to the fast axis of the 1 / 2 wave plate, or the electric field direction of the linearly polarized light is at a 45-degree angle to the slow axis of the 1 / 2 wave plate. Placing the half wave plate after the collimator 400 can ensure that the divergence angle of the incident light beam is small when it enters the half wave plate, thereby preventing additional optical power loss caused by a large divergence angle. The half wave plate can be, for example but not limited to, a zero-order wave plate.

[0176] In some embodiments, the control device 600 of the transmitting module may be an independent device, and the control of the first light deflection device 100 and the second light deflection device 200 is realized by an independent device. The control device 600 may also be a discrete device, see Figure 6 As shown, the control device 600 includes a first control unit 110 and a second control unit 230;

[0177] The first control unit 110 is used to control the first light deflection device 100 to deflect a plurality of different first deflection angles in a deflection period, and to cause the light beam of each first deflection angle to be incident on the second light deflection device 200;

[0178] The second control unit 230 is used to control the second light deflection device 200 to receive the light beam in time division and deflect the light beam to a required second deflection angle.

[0179] In the above-mentioned emission module, the light beam is deflected at multiple different deflection angles by the first light deflection device 100 and the second light deflection device 200 in a time-sharing manner to scan a preset field of view, and the length of the preset field of view in the first direction is less than the length in the second direction. The second direction in which the strip light beam formed by the secondary deflection is longer is set to be consistent with the longer direction of the entire field of view to be scanned, which can reduce the number of angles of the strip light beam deflected by the second light deflection device along the second direction, thereby reducing the volume and cost of the second light deflector, and shortening the light beam deflection time required for scanning.

[0180] In practical applications, the second light deflection device 200 can be configured to deflect the light beams incident at different positions by the same second deflection angle, thereby completing the scanning of a corresponding scanning partition within the field of view; deflect the light beams incident at each of the different positions by multiple different second deflection angles, thereby completing the scanning of multiple scanning partitions corresponding to the different multiple second deflection angles; the scanning partition is rectangular, and the length of the strip light beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition. Optionally, the second optical deflection device 200 is configured to deflect a plurality of light beams with different first deflection angles to the same second deflection angle within one deflection period, so as to complete scanning of a corresponding scanning partition in the field of view; different deflection periods have different second deflection angles for deflecting the light beams with different first deflection angles; or, within one deflection period, deflect a plurality of light beams with different first deflection angles to one of a plurality of different second deflection angles, respectively, to scan partial areas in the corresponding scanning partitions; wherein, within one deflection period, a plurality of light beams with different first deflection angles are deflected to the same or different second deflection angles; and each light beam with the first deflection angle is deflected to a different second deflection angle in different deflection periods.

[0181] The first optical deflection device 100 is, for example but not limited to, an acousto-optic deflector (AOD), which can deflect the light beam according to a preset sound wave frequency. The AOD may include an incident aperture, an acousto-optic crystal, an acoustic wave generator, and an exit aperture. The configuration of the acousto-optic crystal according to a specific scheme can realize quasi-continuous deflection of one-dimensional or two-dimensional light, and the deflection response time is proportional to the width of the light beam in the crystal. The control device 600 is used to apply a driving signal to the acoustic wave generator of the first optical deflection device 100, and control the acoustic wave frequency of the acoustic wave generator acting on the acousto-optic crystal of the first optical deflection device 100 through the driving signal, so as to change the deflection angle of the light beam by the first optical deflection device 100.

[0182] The second light deflection device 200 is, for example but not limited to, a liquid crystal polarization grating. By adjusting the arrangement state of the liquid crystal molecules of the liquid crystal polarization grating, deflection at different second deflection angles can be achieved; the second light deflection device 200 can deflect the light beam at more than one angle in the first direction, and can also deflect the light beam at more than one angle in the second direction, for example Figure 2 and Figure 3 As shown, taking deflection of 2 angles in the first direction and 8 angles in the second direction as an example, in actual application, the number of angles of deflection in each direction is set as needed. The second light deflection device 200 can adopt a partitioned structure or a non-partitioned structure. The liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating sheet included in the liquid crystal polarization grating is a nematic liquid crystal or a blue phase liquid crystal. When the blue phase liquid crystal is used, the speed of the second light deflection device to adjust the deflection angle can be further improved, and the time for adjusting the deflection angle can be shortened.

[0183] In the above-mentioned transmitting module, the incident light beam of each device is different according to the different positional relationships thereof. For example, when the collimating device 400 and the polarization expanding device 500 are not included, the incident light beam of the first light deflection device 100 is the light beam emitted by the light source, and the incident light beam of the second light deflection device 200 is the light beam deflected by the first light deflection device 100. For another example, when the collimating device 400 is not included but the polarization expanding device 500 is included, if the polarization expanding device 500 is arranged between the first optical deflection device 100 and the second optical deflection device 200, the incident light beam of the first optical deflection device 100 is the light beam emitted by the light source, the incident light beam of the polarization expanding device 500 is the light beam deflected by the first optical deflection device 100, and the incident light beam of the second optical deflection device 200 is the light beam deflected by the polarization expanding device 500; if the polarization expanding device 500 is arranged after the second optical deflection device 200, the incident light beam of the second optical deflection device 200 is the light beam deflected by the first optical deflection device 100, and the incident light beam of the polarization expanding device 500 is the light beam deflected by the second optical deflection device 200. For another example, when the deflection expanding device 500 is not included but the collimating device 400 is included, the incident light beam of the collimating device 400 is the light beam emitted by the light source, the light beam after the collimating device of the first light deflecting device 100 is collimated, and the incident light beam of the second light deflecting device 200 is the light beam after deflection by the first light deflecting device 100. Other arrangements are analogous.

[0184] The above-mentioned transmitting module of the embodiment of the present invention can increase the number of deflection angles of the light beam deflected by the deflection device during the process of the light beam scanning the entire field of view (FOV), and can reduce the divergence angle of the light beam after being deflected by the optical deflection device. This is because the light beam needs to cover the angle range of the entire FOV after being deflected a preset number of times. The more the number of deflection angles, the smaller the divergence angle requirement of the light beam. Reducing the divergence angle can increase the power of the light beam per unit divergence angle, which is beneficial to improving the detection distance of the laser radar.

[0185] The above-mentioned emission module can be designed with a specific design scheme as needed. When designing different schemes, the aspect ratio of the scanning field of view, the length ratio of the scanning spot reaching a distance, the splicing method of the light source, etc. can be determined first, which can be adjusted and designed as needed. Then, according to the parameters such as the liquid crystal response time of the liquid crystal polarization grating, the vertical light path and the horizontal light path are designed, and the number and type of lenses in the light path are selected, such as how many collimating lenses and polarization expanding lenses are used respectively, and whether cylindrical lenses or spherical lenses are used; and the positional relationship between each device. In this way, the light beam with a certain aspect ratio emitted by the light source is collimated, and the collimated light beam with a relatively small aspect ratio is incident on the first light deflection device 100, and the first light deflection device 100 deflects in the first direction, and the second light deflection device 200 deflects in the first direction and the second direction. The polarization expanding device can be added before or after the second light deflection device as needed, so that the light beam projected to the distant scanning area forms a long strip scanning light beam with a relatively large aspect ratio. The following are several design scheme examples:

[0186] Design 1

[0187] According to the aspect ratio of the scanning field of view, the aspect ratio of the scanning spot reaching a distance can be designed to be greater than a certain value, for example, greater than 10:1. The light source is a plurality of EELs (light emitting units 310) whose instantaneous power meets the requirements and are spliced ​​along the long axis (horizontal) direction, see Figure 5 shown.

[0188] Design Scheme 1 assumes that the liquid crystal response time of the liquid crystal polarization grating is 5ms. The collimating device 400 uses collimating lenses F1 and F2, the first light deflecting device 100 uses AOD, the second light deflecting device 200 uses a partitioned LCPG module, and the polarization expanding device 500 uses polarization expanding lenses F3, F4, F5 and F6.

[0189] In the vertical direction, the collimating lens F2 is used to collimate the light beam, and the expanding lenses F3 and F4 are used to expand the light beam. In the horizontal direction, the collimating lens F1 is used to collimate the light beam, and the expanding lenses F5 and F6 are used to expand the light beam.

[0190] The components of this design are selected as shown in Table 1 below:

[0191] Table 1

[0192] Scanning spot shape Greater than 10 (H) * 1 (V) AOD Clear Aperture Within the range of 1(H)*5(V)~5(H)*1(V) LCPG module light deflection unit quantity 3 (H) * 1 (V) LCPG module deflection angle quantity 8 (H) * 2 (V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Cylindrical lenses F3, F4, F5, F6

[0193] In the table, H represents the horizontal direction, V represents the vertical direction, and 5(H)*1(V) means that the aspect ratio of the horizontal direction to the vertical direction is 75:1.

[0194] The length L from the light source to the second light deflection device (LCPG module) is calculated by the following formula:

[0195] L=2*(F1+F3+F4)+d;

[0196] F1, F3 and F4 are the focal lengths of lenses F1, F3 and F4 respectively, and d is the length from the back focal plane of lens F4 to LCPG. The calculation formula for d is:

[0197] ,

[0198] Where Θv is the vertical deflection angle of the light beam after passing through the AOD and the polarization expanding lens group, θv is the vertical divergence angle of the light beam at this time, and Wv is the vertical waist diameter of the light beam after passing through the AOD and the polarization expanding lens group. Θv and θv are given by the scanning spot parameters. The calculation formula of Wv is as follows;

[0199] Wv=Wv0 * θv0 / θv,

[0200] Wv0 and θv0 are the waist diameter and divergence angle of the laser beam emitted by the laser light source in the vertical direction.

[0201] The total dimensions of LCPG in horizontal and vertical directions are;

[0202] Lh=d*2*tan(Θh / 2),

[0203] Lv=d*2*tan(Θv / 2),

[0204] Θh is the horizontal divergence angle of the laser beam incident on the LCPG module.

[0205] The vertical optical path is designed as follows:

[0206] The vertical direction is the AOD deflection direction, and the deflection angle range and the vertical divergence angle of the light beam after passing through the collimating lens F2 are set.

[0207] The AOD diffracted light beam is first expanded by a specified multiple by the vertical cylindrical lens group F3 and F4, and then expanded by 2 times by the LCPG to cover the vertical scanning area.

[0208] The LCPG module needs to complete 2 discrete angles in the vertical direction and 8 discrete angles in the horizontal direction, a total of 16 angles of deflection, which requires 4 layers of LCPG.

[0209] The response time of the LCPG module is set to 5ms. During the spot scanning, the deflection partition in the LCPG module illuminated by the spot cannot adjust the deflection direction. In order to meet the requirement of completing 2*8 deflections in a total of 16 times within 100ms, each layer of the liquid crystal half-wave plate needs to be divided into 10 equal pieces in the vertical direction.

[0210] according to Figure 7a and Figure 7bThe optical path shown can be used to calculate the vertical size of the LCPG module and the focal plane distance of the LCPG from F4.

[0211] The horizontal optical path is designed as follows:

[0212] In the horizontal direction, the AOD does not deflect the incident laser beam. The laser beam emitted from the AOD is firstly contracted by the horizontal cylindrical lens group F5 and F6 and the divergence angle is increased by 2 times.

[0213] Then it passes through the LCPG module and deflects in 8 directions in the horizontal direction to cover the horizontal scanning area.

[0214] Based on the condition that the response time of LCPG is 5ms, the placement position of LCPG has been calculated in the above vertical optical path design, from which the horizontal size of LCPG can be calculated.

[0215] Design 2

[0216] The difference between this solution and design solution 1 is that the horizontal optical path configuration is different.

[0217] The collimating device 400 uses collimating lenses F1 and F2, the first light deflecting device 100 uses AOD, the second light deflecting device 200 uses a partitioned LCPG module, and the polarization expanding device 500 uses polarization expanding lenses F3 and F4.

[0218] In the vertical direction, the collimating lens F2 is used to collimate the light beam, and the expanding lenses F3 and F4 are used to expand the light beam. In the horizontal direction, the collimating lens F1 is used to collimate the light beam.

[0219] The components of this design are selected as shown in Table 2 below:

[0220] Table 2

[0221] Scanning spot shape Greater than 10 (H) * 1 (V) AOD Clear Aperture Within the range of 1(H)*5(V)~5(H)*1(V) LCPG module light deflection unit quantity 3 (H) * 1 (V) LCPG module deflection angle quantity 8 (H) * 2 (V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Cylindrical lens F3, F4

[0222] The length L from the light source to the second light deflection device (LCPG module) in this scheme is consistent with that in design scheme 1.

[0223] The vertical optical path design of this design is the same as that of Scheme 1, and the horizontal optical path design is as follows:

[0224] In the horizontal direction, the AOD does not deflect the incident laser beam. The horizontal divergence angle of the output AOD is a specified degree, and there is no horizontal beam reduction lens group to expand the deflection.

[0225] Then it passes through the LCPG module and deflects in 8 directions in the horizontal direction to cover the horizontal scanning area.

[0226] Under the condition that the response time of the LCPG module is 5ms, the placement position of the LCPG has been calculated in the above vertical optical path design, from which the horizontal size of the LCPG can be calculated.

[0227] The structural difference between Scheme 2 and Scheme 1 is that the cylindrical lenses F5 and F6 for horizontal beam expansion are omitted, but the light receiving area of ​​the LCPG module needs to be increased accordingly.

[0228] Difference in technical effects: Since the cylindrical lens combination F5 and F6 that only expands the beam in the horizontal direction may affect the divergence of the beam in the vertical direction, considering this point, Scheme 2 omits cylindrical lenses F5 and F6, but the size of the LCPG module needs to be increased accordingly to receive the entire beam. Scheme 1 and Scheme 2 are the same in the distance between the light source and the LCPG module, so there is no difference in system size.

[0229] Design 3

[0230] According to the aspect ratio of the scanning field of view, the aspect ratio of the scanning spot reaching a distance can be designed to be greater than a certain value, for example, greater than 10: 1. The light source is a plurality of EELs whose instantaneous power meets the requirements and are spliced ​​along the long axis (horizontal) direction.

[0231] Assuming the response time of the liquid crystal is 5ms, the aperture size of the AOD is up to 8*4 or 8*3.

[0232] The collimating lens is two cylindrical lenses F1 and F2, and the expanding lens is two spherical lenses F3 and F4.

[0233] The components of this design are selected as shown in Table 3 below:

[0234] Table 3

[0235] Scanning spot shape Greater than 10 (H) * 1 (V) AOD Clear Aperture Within the range of 1(H)*5(V)~5(H)*1(V) LCPG module light deflection unit quantity 3 (H) * 1 (V) LCPG module deflection angle quantity 8 (H) * 2 (V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Spherical lens F3, F4

[0236] In design scheme 3, the LCPG module has 4 layers, that is, 4 light deflection units realize deflection of 16 separation angles.

[0237] In this solution, in the vertical direction, the light source has a width of V1 and a divergence angle of θ1, and is collimated by a cylindrical lens with a focal length of F2. The distance between the optical center of the F2 lens and the light source is preferably the focal length F2.

[0238] Similarly, in the horizontal direction, the light source has a width H1 and a divergence angle θ1, and is collimated by a cylindrical lens with a focal length F1. The distance between the optical center of the F1 lens and the light source is preferably the focal length F1.

[0239] The collimated light beam enters the AOD. In the vertical direction, the divergence angle of the light beam is θ2, and the beam waist diameter is V2, which satisfies the relationship θ2= V1 / F2, θ2 V2=θ1 V1. Similarly, in the horizontal direction, the divergence angle of the light beam is θ2, and the beam waist diameter is H2, which satisfies the relationship θ2= H1 / F1, θ2 H2=θ1 H1.

[0240] In this solution, the light source is generally selected to be a long strip of EEL light source. For example, H1>>V1 can be selected. , so we can choose the appropriate lens focal length F1, F2 to make In this way, after the light spot passes through the subsequent spherical lens, it will appear as a long strip in the far field.

[0241] In order to allow as much light energy as possible to pass through the AOD, the vertical aperture of the AOD is preferably greater than or equal to V2, and the horizontal aperture is preferably greater than or equal to H2. The distance between the AOD and the light source is preferably 2*F1. This is because Therefore, after collimation, the laser is nearly parallel in the vertical direction, but still has a large divergence angle in the horizontal direction. Placing the AOD at twice the focal length of F1 from the light source ensures that the AOD's vertical aperture can be minimized to V2.

[0242] The AOD is configured to deflect the light beam in the vertical direction. In the collimator 400, the first cylindrical lens strictly collimates the light beam in the vertical direction, requiring a divergence angle θ2 ≤ 0.3°; the second cylindrical lens non-strictly collimates the light beam in the horizontal direction, and in practice, a divergence angle of θ2 ≤ 0.3° is allowed. .

[0243] The light beam exits the AOD and enters the expansion device, which deflects and amplifies the light beam emitted by the AOD. This solution takes the Kepler lens group as an example. The focal lengths of the two expansion lenses are F3 and F4, respectively, and their expansion multiples are F3 / F4. If the AOD deflects the light beam by +-1.5 degrees, then the deflection range becomes +-(1.5* F3 / F4) degrees after passing through the AOD. Synchronously, the divergence angle of the light beam, θ2, The distance between AOD and the first polarization expanding lens F3 is its focal length F3, and the interval between polarization expanding lens group F3 and F4 is F3+F4. After passing through F3 and F4, the light beam is narrowed to the minimum at the rear focal plane of the lens, where V3=V2*F4 / F3 in the vertical direction and H3=H2*F4 / F3 in the horizontal direction.

[0244] The LCPG module includes at least one LCPG unit, and each LCPG unit includes a liquid crystal half-wave plate and an LCPG sheet.

[0245] The thickness of the liquid crystal half-wave plate and LCPG plate is mainly determined by the thickness of the glass substrate. In practice, the thickness of the glass substrate is generally <<1mm, and the total thickness of the multi-layer liquid crystal is <1mm. In this case, the thickness of the LCPG can be ignored in the optical path design.

[0246] The LCPG sheet in this solution can be passive LCPG or active LCPG. The difference between the two is:

[0247] Passive LCPG does not require voltage to be applied during operation. The LCPG module using passive LCPG only needs to apply corresponding voltage to the liquid crystal half-wave plate to realize the deflection of the light beam during operation.

[0248] During operation, the active LCPG needs to apply corresponding voltages corresponding to different deflection angles. During operation, the LCPG module using the active LCPG needs to apply corresponding voltages to the liquid crystal half-wave plate and the active LCPG respectively.

[0249] In this solution, the LCPG units that deflect the light beam along the deflection direction with fewer deflection angles can be arranged in the front order on the optical path to improve the diffraction efficiency of the light beam. However, the corresponding light beam deflection function can also be achieved without following the above order requirements.

[0250] The above are several design examples of the transmitting module. In practical applications, the optical path design and device selection of the transmitting module can be designed according to scanning needs.

[0251] Several optional structures of the above-mentioned transmitting module of the present invention are described below through specific embodiments.

[0252] Embodiment 2

[0253] The transmission module provided in the second embodiment of the present invention has a structural diagram as shown in Fig. 9 As shown, the three-dimensional structure diagram is shown in Figure 6 As shown, the transmitting module includes a light source 300, a collimating device 400, a first light deflecting device 100, a deflection expanding device 500, a second light deflecting device 200 and a control device 600. In this embodiment, the first light deflecting device 100 performs one-dimensional deflection on the light beam in the first direction, and the second light deflecting device 200 performs two-dimensional deflection on the light beam in the first direction and the second direction. In this embodiment, the second light deflecting device 200 adopts a partition structure. In this transmitting module:

[0254] A light source 300, for emitting a light beam, wherein the length of the light beam along the first direction is shorter than the length of the light beam along the second direction;

[0255] The collimating device 400 is configured to collimate the light beam before the light beam enters the first light deflecting device 100;

[0256] The first light deflection device 100 is configured to deflect the light beam along a first direction by a plurality of first deflection angles within a deflection period;

[0257] The deflection expanding device 500 is disposed between the first light deflection device and the second light deflection device, and is configured to amplify the deflection angle of the light beam deflected by the first light deflection device 100 by a preset multiple and then make it incident on the second light deflection device 200;

[0258] The second light deflection device 200 is configured to deflect the light beam deflected by the first light deflection device 100 by a plurality of second deflection angles along the first direction and the second direction;

[0259] The control device 600 is used to control the light source 300 to emit a light beam, and control the first light deflection device 100 and the second light deflection device 200 to deflect the light beam.

[0260] The collimating device 400 may be a collimating lens, the first light deflecting device 100 may be an AOD, the polarization expanding device 500 may be a polarization expanding lens, and the second light deflecting device 200 may be an LCPG module. Figure 7a As shown, the light path in the second direction (horizontal direction) is shown in Figure 7b shown.

[0261] The light source 300 emits a strip light beam, which is collimated by the collimator 400 and then irradiated to the first light deflection device 100, wherein the width direction of the strip light beam is the first direction and the length direction is the second direction. Figure 5 As shown, the light source 300 may include a plurality of light emitting units 310 .

[0262] The collimator 400 collimates the light beam in both the first direction and the second direction, and a light source control unit can be used to control the light source to emit light in a preset time sequence, wherein the collimation degree in the first direction is required to be higher, so that the divergence angle of the light beam in the first direction is smaller. This requirement can be achieved through the characteristics of the collimator 400. Since the collimator 400 collimates the light beam, the size of the collimated light beam and the divergence angle have an inversely proportional relationship, so a higher collimation degree can be obtained in the width direction of the strip light beam than in the length direction. Figure 7a and Figure 7b As shown, two collimating lenses collimate the light beam in a first direction and a second direction respectively, and the figure takes two cylindrical lenses as an example.

[0263] The first light deflection device 100 deflects the light beam in a first direction, and can deflect the light beam at a plurality of first deflection angles within a preset angle range, and the plurality of first deflection angles can have a set angle interval. The first light deflection device 100 can deflect the light beam according to a preset time sequence.

[0264] The light beam deflected by the first light deflection device 100 is expanded by the expansion device 500 to expand the deflection angle of the light beam in the first direction and the second direction. Figure 7a As shown, two polarization expanding lenses expand the light beam in the first direction, and the deflection angle of the light beam emitted from the first optical deflection device 100 is increased after passing through the two polarization expanding lenses in the first direction, and the polarized light beam is then projected to the corresponding position of the second optical deflection device 200. Figure 7b As shown, two expanding lenses expand the light beam in the second direction, and the deflection angle of the light beam emitted from the first optical deflection device 100 is increased after passing through the two expanding lenses in the first direction, and the expanded light beam is then projected to the corresponding position of the second optical deflection device 200.

[0265] The second light deflection device 200 deflects the light beam. In this embodiment, the second light deflection device 200 can deflect the light beam at multiple different angles in the first direction and the second direction. For example, the light beam can be deflected at two angles in the first direction and at eight angles in the second direction.

[0266] The second light deflection device 200 may adopt a partitioned structure or a non-partitioned structure.

[0267] In this embodiment, the partition structure of the second light deflection device 200 is used as an example for description. The partition structure of the second light deflection device 200 can solve the problem that when the laser radar uses a liquid crystal polarization grating to realize beam deflection, the deflection angle switching waiting time is long and the angle adjustment is slow, which affects the laser radar scanning detection frame rate. The second light deflection device is divided into different deflection partitions. After the light beams with different first deflection angles are expanded, they can be projected onto different deflection partitions of the second light deflection device 200. Each deflection partition can use the time when it is not irradiated to adjust the deflection angle. The scanning system does not need to wait for the light deflection device to adjust the state to change the deflection angle, so that the scanning can be carried out continuously, thereby avoiding the waiting time for angle adjustment, improving the switching speed, and can still meet the detection frame rate requirements while increasing the number of beam deflection angles. This design achieves high frame rate, large field of view and long-distance measurement capability, and can meet the requirements of application scenarios such as vehicle-mounted laser radar. In this embodiment, the deflection partitions in the second light deflection device 200 are arranged correspondingly along the first direction.

[0268] The structure of the second light deflection device 200 with a partition structure is shown in FIG. Fig.10a , 10b, 10c and 10d. The second light deflection device 200 may include a plurality of deflection partitions 212, and the plurality of deflection partitions 212 may independently adjust the deflection angle, that is, each deflection partition 212 may independently adjust the deflection angle of the incident light beam; in the case of adopting a partition structure:

[0269] The first light deflection device 100 is configured to deflect the incident light beam to a plurality of different first deflection angles within a deflection period so as to be incident on corresponding deflection subareas 212 of the second light deflection device 200;

[0270] A plurality of deflection sub-areas 212, configured with a second deflection angle required for the currently scanned deflection sub-area 212 to deflect the incident light beam;

[0271] The control device 600 is used to control the first optical deflection device 100 to deflect the incident light beam and control the currently scanned deflection partition 212 in the second optical deflection device 200 to deflect the incident light beam, and control at least one deflection partition 212 that is not currently scanned to adjust its deflection angle of the light beam, so that the deflection angle of at least one deflection partition 212 to the incident light beam is adjusted to the second deflection angle required for the next deflection cycle after the incident light beam scan ends in the current deflection cycle and before the incident light beam scan starts in the next deflection cycle.

[0272] The control device 600 can be used to control the first light deflection device 100 to deflect the incident light beam to a plurality of different first deflection angles within a deflection cycle, so as to correspond to the incident light beam incident on the corresponding deflection partition of the second light deflection device 200; it can also be used to control the currently scanned deflection partition in the second light deflection device 200 to deflect the incident light beam to the required second deflection angle; it can also be used to control at least one deflection partition 212 that is not currently scanned to adjust its deflection angle of the light beam, so that the deflection angle of at least one deflection partition 212 to the incident light beam is adjusted to the second deflection angle required for the next deflection cycle after the incident light beam scans the current deflection cycle and before the incident light beam scans the next deflection cycle. Optionally, the control device 600 is specifically used to perform the following control processes in parallel: controlling the currently scanned deflection partition in the second light deflection device 200 to deflect the incident light beam, and controlling at least one deflection partition 212 that is not currently scanned to adjust its deflection angle of the light beam. That is to say, while the deflection subarea 212 currently being scanned of the second light deflection device 200 deflects the incident light beam, at least one deflection subarea 212 currently not being scanned may adjust its deflection angle of the light beam under the control of the control device 600 .

[0273] The control device 600 controls the first optical deflection device 100 to deflect the light beam to multiple different first deflection angles in a time-sharing manner in correspondence to the multiple deflection partitions 212 incident on the second optical deflection device 200, and the multiple deflection partitions 212 receive the incident light beam in a time-sharing manner and deflect the incident light beam; wherein the deflection period is the time required for the multiple deflection partitions 212 to be scanned once by the incident light beams of multiple different first deflection angles. In other words, the deflection period is the time required for the incident light beams of multiple different first deflection angles to traverse and scan the multiple deflection partitions 212. In this case, within one deflection period, all the incident light beams of multiple different first deflection angles will scan all the deflection partitions 212, that is, each deflection partition 212 will be scanned and will not be missed.

[0274] Or, the deflection period is the time required for a portion of the deflection partitions 212 specified in the multiple deflection partitions 212 to be scanned once by an incident light beam of a portion of the first deflection angles specified in the multiple different first deflection angles. In other words, the deflection period is the time required for an incident light beam of a portion of the first deflection angles specified in the multiple different first deflection angles to traverse and scan the portion of the deflection partitions 212 specified in the multiple deflection partitions. In one deflection period, some of the deflection partitions in the multiple deflection partitions 212 are scanned, that is, some of the deflection partitions 212 are missed. The portion of the deflection partitions 212 specified by different deflection periods may be the same or different, and correspondingly, the incident light beam of the specified portion of the first deflection angles may be the same or different.

[0275] In each deflection cycle, the control device 600 can control the first optical deflection device 100 to generate a plurality of incident light beams with different first deflection angles within a preset angle range and according to a preset deflection time interval, and project them onto the corresponding deflection partitions of the second optical deflection device 200. In one deflection cycle, the control device 600 can control the first optical deflection device 100 to deflect the incident light beam to a plurality of different first deflection angles in a time-division manner, and the incident light beams with a plurality of different first deflection angles are incident to a plurality of deflection partitions in a time-division manner, and the plurality of deflection partitions of the second optical deflection device 200 receive the incident light beams in a time-division manner and deflect the incident light beams. In addition, the first optical deflection device 100 is configured to sequentially incident the incident light beams with a plurality of different first deflection angles onto the corresponding deflection partitions of the second optical deflection device 200 in a preset order in one deflection cycle; and a deflection partition 212 is configured to deflect the incident light beam to a corresponding second deflection angle in one deflection cycle.

[0276] The above-mentioned second optical deflection device 200 can realize the control of at least one deflection partition 212 to complete the adjustment of the second deflection angle once within the scanning interval of two adjacent deflection cycles through the control device 600, so that at least one deflection partition can be adjusted to the required second deflection angle before the incident of the last scanned deflection partition 212 ends. That is to say, the control device 600 can control the light beam emitted by the first optical deflection device 100 to hit each deflection partition 212 in a time-sharing manner, and at least one deflection partition 212 will respond in advance to prepare for receiving the incident light beam in the next deflection cycle. Before the light beam in the next deflection cycle is incident on the deflection partition 212, the deflection angle of the incident light beam by the deflection partition 212 has been pre-adjusted to the second deflection angle required for the next deflection cycle, which can reduce the waiting time for angle adjustment to a certain extent, so that at least one incident light beam in the next deflection cycle can be irradiated without waiting, thereby improving the scanning frame rate of the optical scanning. In order to further improve the scanning frame rate, optionally, the control device 600 can control each deflection partition 212 to complete an adjustment of the second deflection angle within the incident interval of two adjacent deflection cycles, so that each deflection partition 212 can be adjusted to the required second deflection angle before the incident of the last scanned deflection partition 212 ends, so that each incident light beam of the first deflection angle can be directly irradiated without waiting, thereby improving the scanning frame rate of the light scanning.

[0277] In a deflection cycle, multiple incident light beams with different first deflection angles can be incident on the corresponding deflection partitions 212 in sequence according to a preset order; the incident order of multiple incident light beams with different first deflection angles can be preset and can be realized by the control of the control device 600. Optionally, the deflection angles of multiple light beams with different first deflection angles change from large to small in the first direction, or change from small to large, or change according to a preset random rule. Optionally, the deflection angles of multiple light beams with different first deflection angles can change from large to small, for example: from -1.5, -1.0, -0.5, 0, 0.5, 1, 1.5 in sequence. Optionally, the deflection angles of multiple light beams with different first deflection angles can change from small to large, for example: from 1.5, 1.0, 0.5, 0, -0.5, -1, -1.5 in sequence. Optionally, the deflection angles of the light beams of the light deflection unit group with multiple different first deflection angles can also change according to a preset random rule, for example: randomly changing from -1.5, 1, -0.5, 0, -1.0, 0.5, 1.5. In different deflection periods, the incident order of the incident light beams can be the same or different.

[0278] In the above-mentioned second optical deflection device 200, the multiple deflection partitions 212 are configured to have multiple second deflection angles for deflecting the incident light beam in one deflection cycle that are all the same, or all different, or partially the same and partially different. Optionally, in one deflection cycle, the second deflection angles for deflecting the incident light beams of multiple first deflection angles can be one, or two or more. For example: in one deflection cycle, the multiple deflection partitions 212 deflect the incident light beams of multiple different first deflection angles by 1 degree; in the next cycle, the multiple deflection partitions 212 deflect the incident light beams of multiple different first deflection angles by 2 degrees; ... and so on; for another example: in one deflection cycle, the first deflection partition 212 deflects the incident light beam of at least one first deflection angle by 1 degree; the second deflection partition 212 deflects the incident light beam of at least one first deflection angle by 2 degrees; ... and so on. For another example: within one deflection cycle, the first deflection partition 212 deflects at least one incident light beam of the first deflection angle by 1 degree; the second deflection partition 212 deflects at least one incident light beam of the first deflection angle by 1 degree; the third deflection partition 212 deflects at least one incident light beam of the first deflection angle by 3 degrees; the fourth deflection partition 212 deflects at least one incident light beam of the first deflection angle by 5 degrees; ...and so on.

[0279] In the second light deflection device 200, a deflection subarea 212 may be configured to receive at least one incident light beam with a first deflection angle. Optionally, a deflection subarea 212 may be configured to sequentially receive one, two or more incident light beams with different first deflection angles within a deflection cycle.

[0280] In the above-mentioned second optical deflection device 200, the arrangement direction of the multiple deflection partitions 212 is consistent with the scanning direction of the incident light beams of multiple different first deflection angles. The multiple deflection partitions 212 can be arranged one-dimensionally along one direction, or can be arranged in a two-dimensional array. The arrangement direction can be consistent with the scanning direction of the incident light beam of the first deflection angle. For example, if the incident light beam is scanned along the first direction, the multiple deflection partitions 212 are also arranged along the first direction; if the incident light beam is scanned in a two-dimensional array, the multiple deflection partitions are arranged in a two-dimensional array. The scanning method of the incident light beam can be related to the shape of the incident light beam. In this application, the arrangement along one direction is taken as an example.

[0281] When the incident light beam is a strip light beam with an aspect ratio greater than a set threshold, the first light deflection device 100 is configured to deflect the incident light beam along the first direction by a plurality of different first deflection angles within one deflection period, so as to perform one-dimensional scanning on the second light deflection device 200, and the plurality of deflection sub-areas 212 included in the second light deflection device 200 are arranged along the first direction of the light beam; for example Fig.10a , 10bAs shown in , 10c and 10d, the multiple deflection partitions 212 are arranged in the vertical direction. The deflection partition 212 can be a rectangle with an aspect ratio greater than a set threshold. The width direction of the deflection partition is consistent with the scanning direction of the incident light beams of the multiple different first deflection angles, that is, the width direction of the deflection partition is along the first direction, and the length direction of the deflection partition is along the second direction.

[0282] In the above-mentioned second light deflection device 200, the plurality of deflection partitions 212 are configured such that the number of incident light beams received by each deflection partition 212 is the same, different, or partially the same and partially different; accordingly, the widths of the plurality of deflection partitions 212 are the same, different, or partially the same and partially different. The light beam incident surface of the deflection partition is a rectangle with an aspect ratio greater than a set threshold, the width direction of the deflection partition is consistent with the scanning direction of the light beams of the plurality of different first deflection angles, and the width of each deflection partition 212 is determined according to the number of incident light beams received and the width of the incident light beam.

[0283] It can be set that the number of incident light beams received by each deflection partition 212 is the same. For example, each deflection partition 212 receives one incident light beam, that is, the incident light beams of the deflection partition 212 are one-to-one corresponding, or each deflection partition 212 receives two or more incident light beams, and the deflection partition 212 and the incident light beams are in a one-to-two or one-to-many relationship. In this case, the width of each deflection partition 212 can be the same, and the width of each deflection partition 212 is equal to the sum of the widths of the corresponding light beams received. For example, in the one-to-two case, the width of a deflection partition 212 is equal to the sum of the widths of the two light beams.

[0284] It can be configured that the number of incident light beams received by each deflection partition 212 is different, for example, the first deflection partition 212 receives one incident light beam, the second deflection partition 212 receives two incident light beams, the third deflection partition 212 receives three incident light beams, ... In this case, the width of each deflection partition 212 is different, and the width of each deflection partition 212 is equal to the sum of the widths of the light beams received by it.

[0285] It can be configured that the number of incident light beams received by each deflection partition 212 is partially the same and partially different, for example, the first deflection partition 212 receives one incident light beam, the second deflection partition 212 receives two incident light beams, the third deflection partition 212 receives one incident light beam, the fourth deflection partition 212 receives two incident light beams, ... In this case, the width of each deflection partition 212 is partially the same and partially different, and the width of each deflection partition 212 is equal to the sum of the widths of the light beams received by it.

[0286] In some optional embodiments, the control device 600 can determine whether the deflection angle of each deflection partition 212 can be adjusted according to the scanning state of each deflection partition 212. Each deflection partition 212 can adjust its deflection angle of the light beam when it is in a non-scanning state. The above-mentioned control device 600 can also be used to determine whether each deflection partition 212 is in a scanning state. After determining that a deflection partition 212 has completed the deflection of the incident light beam in the current deflection cycle and is in a non-scanning state, the deflection partition 212 is controlled to adjust its deflection angle of the light beam. Before entering the scanning state in the next deflection cycle, the deflection angle of the light beam of the deflection partition 212 is adjusted to the second deflection angle required for the next deflection cycle. Each deflection partition 212 can start to adjust the deflection angle of the light beam after it completes the deflection of the light beam in the current deflection cycle and is in a non-scanning state, so as to better ensure that the angle can be adjusted in time. The non-scanning state refers to a state where there is no incident light beam and no light beam deflection is required.

[0287] In practical applications, the deflection partition 212 currently scanned by the light beam can be determined as the deflection partition in the scanning state, and the remaining deflection partitions 212 can be determined as the deflection partition in the non-scanning state. That is, if a deflection partition is the deflection partition currently scanned by the incident light beam, the deflection partition is determined to be in the scanning state, otherwise, the deflection partition is determined to be in the non-scanning state.

[0288] Optionally, the deflection partition 212 currently scanned by the light beam and the next deflection partition 212 to be scanned can also be determined as deflection partitions in a scanning state, and the remaining deflection partitions 212 can be determined as deflection partitions in a non-scanning state. The remaining deflection partitions 212 include all deflection partitions in the second optical deflection device 200 except the deflection partition 212 currently scanned by the light beam and the next deflection partition 212 to be scanned; the deflection partition currently scanned by the light beam and the next deflection partition to be scanned can be adjacent deflection partitions in position or can be non-adjacent deflection partitions in position. That is to say, if a deflection partition 212 is the deflection partition currently scanned by the incident light beam or the next deflection partition to be scanned, it is determined that the deflection partition 212 is in a scanning state, otherwise, it is determined that the deflection partition 212 is in a non-scanning state. The deflection partition currently scanned by the incident light beam and the next deflection partition to be scanned can be adjacent deflection partitions in position or can be non-adjacent deflection partitions in position. The incident light beam is usually scanned into each deflection partition 212 according to a set order. The control device 600 can determine the next deflection partition to be scanned based on the currently scanned deflection partition and the scanning order.

[0289] Since the incident light beam deflected by the first light deflection device 100 can irradiate different positions of the second light deflection device 200, and different positions of the second light deflection device 200 correspond to different deflection partitions, it is possible to determine which deflection partitions are in a scanning state and which deflection partitions are in a non-scanning state according to the incident position. The control device 600 is specifically used to determine the deflection partition 212 currently in the scanning state and the deflection partition 212 in the non-scanning state according to the scanning position of the incident light beam on the second light deflection device 200; for the deflection partition 212 in the non-scanning state, if the scanning order of the deflection partition 212 is before the deflection partition 212 in the scanning state, it is considered that the deflection partition has completed the light beam deflection of the current deflection cycle, and the deflection angle of the deflection partition 212 to the light beam can be adjusted to the second deflection angle required for the next deflection cycle.

[0290] The deflection angle adjustment of each deflection partition in the second optical deflection device 200 can be achieved by changing the voltage on the electrode. Different deflection devices have different principles for deflecting light beams. For an optical deflection device that changes the deflection angle by changing the refractive index, when the second optical deflection device 200 is a non-partitioned structure, the control device 600 is used to control the voltage applied to the electrode of the second optical deflection device 200 to adjust the refractive index of the medium in the second optical deflection device 200 to the incident light beam, so as to adjust the deflection angle of the second optical deflection device 200 to the incident light beam; when the second optical deflection device 200 is a partitioned structure, the control device 600 is used to control the voltage applied to the electrode of each deflection partition 212 to adjust the refractive index of the medium in the deflection partition 212 to the incident light beam, so as to adjust the deflection angle of the deflection partition 212 to the incident light beam.

[0291] For example: when the second light deflection device 200 adopts a liquid crystal polarization grating and is a non-partitioned structure, the control device 600 is used to control the voltage applied to the electrodes of the second light deflection device to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating, so as to change the second deflection angle of the second light deflection device to the light beam; when the second light deflection device 200 adopts a liquid crystal polarization grating and is a partitioned structure, the control device 600 is used to control the voltage applied to the electrodes of each deflection partition 212 to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating, so as to change the second deflection angle of the deflection partition to the incident light beam.

[0292] In some optional embodiments, see Fig.10a , 10b, 10c and 10d, the second optical deflection device 200 includes at least one optical deflection unit 210, and the optical deflection unit 210 includes a plurality of deflection sub-partitions 2121; the deflection sub-partitions 212 include a corresponding deflection sub-partition 2121 in the at least one optical deflection unit 210. When the second optical deflection device 200 includes one optical deflection unit 210, the deflection sub-partition is one deflection sub-partition 2121 on the one optical deflection unit 210; when the second optical deflection device 200 includes two optical deflection units 210, the deflection sub-partition includes two corresponding deflection sub-partitions 2121 on the two optical deflection units 210. When the second optical deflection device 200 includes a plurality of optical deflection units 210, the deflection sub-partition 212 includes a plurality of deflection sub-partitions 2121 on the plurality of optical deflection units 210. The above-mentioned second optical deflection device 200 may include one or more optical deflection units 210, and the number of optical deflection units 210 is related to the number of the second deflection angles. Fig.10a , 10b , 10c and 10d are illustrated by taking four optical deflection units 210 as an example. In actual applications, the number of optical deflection units 210 can be set as needed, and multiple required deflection angles can be combined through the deflection angles of each optical deflection unit 210. For example, when one optical deflection unit 210 can achieve two angles of deflection, if four angles of deflection are required during light scanning, two optical deflection units 210 are set; if eight angles of deflection are required, three optical deflection units 210 are set; if sixteen angles of deflection are required, four optical deflection units 210 are set; and so on. That is, the number N of the optical deflection units 210 is proportional to the number of required deflection angles. Satisfaction between the two .

[0293] The optical deflection unit 210 includes deflection sub-partitions 2121 that can independently adjust the deflection angle of the light beam. Since the optical deflection unit 210 has multiple deflection sub-partitions 2121 that can independently control the deflection angle, light beams with different deflection angles can be incident on one of the deflection sub-partitions 2121 and deflected. Therefore, the deflection angle of the light beam can be adjusted by using the time when the deflection sub-partition 2121 is not scanned. When the second optical deflection device 200 includes at least one optical deflection unit 210, the control device 600 is specifically used to control the voltage on the two end electrodes of each deflection sub-partition 2121 respectively, and change the deflection angle of at least one deflection sub-partition to the incident light beam by changing the voltage on the two end electrodes of at least one deflection sub-partition 2121, so as to achieve the change of the second deflection angle of the incident light beam of the corresponding deflection sub-partition 212. That is, by adjusting the deflection angle of some or all of the deflection sub-partitions 2121 in the multiple deflection sub-partitions 2121 to the light beam, the second deflection angle of the entire deflection sub-partition 212 to the incident light beam is changed.

[0294] The second optical deflection device 200 can deflect the incident light beam in one direction or in two different directions. When the light beam only needs to be deflected in one direction, the at least one optical deflection unit 210 included in the second optical deflection device 200 deflects the incident light beam in the same direction. In this case, the number of the optical deflection units 210 is set according to the number of second deflection angles required to be deflected, which can be one, two, or more.

[0295] In order to achieve angular deflection of the light beam in two different directions, the second light deflection device 200 may include at least two light deflection units 210, or the second light deflection device 200 includes at least two light deflection unit groups 220, each light deflection unit group 220 includes at least one light deflection unit 210, wherein at least one light deflection unit group 220 is configured to deflect the light beam in a first direction, and at least one light deflection unit group 220 is configured to deflect the light beam in a second direction, and the first direction and the second direction may be perpendicular to each other.

[0296] Optionally, the light deflection unit group 220 with a smaller number of light beam deflection angles is arranged at a position relatively closer to the light incident side. Thus, a better deflection effect can be obtained. Fig.10a , 10b , 10c and 10d, the optical deflection unit group 220 for deflecting in the first direction includes an optical deflection unit 210, which is placed on the far left to achieve deflection at two angles in the first direction. Figure 7a The schematic diagram of the optical path of the emission module deflecting the light beam along the first direction is shown. The light beam emitted by the light source 300 is collimated by the collimator 400 and then incident on the first light deflection device 100. The deflected light beam is expanded by the expansion device 500 and then incident on the corresponding different deflection partitions on the second light deflection device 200. The second light deflection device 200 can deflect at two different angles in the first direction; the light deflection unit group 220 for deflecting in the second direction includes three light deflection units 210, which are placed on the far right to achieve deflection at eight angles in the second direction, see Figure 7b The optical path diagram of the emission module deflecting the light beam along the second direction is shown. The light beam emitted by the light source 300 is collimated by the collimator 400 and then incident on the first light deflection device 100. The deflected light beam is expanded by the expansion device 500 and then incident on the second light deflection device 200. The second light deflection device 200 can deflect at 8 different angles in the second direction. Figure 7bOnly three angles are shown in the figure. The light deflection unit 210 for light beam deflection along the deflection direction with fewer deflection angles is arranged at the front of the optical path, which can improve the diffraction efficiency of the light beam passing through. The corresponding light beam deflection function can also be achieved without being arranged in the above order.

[0297] The above-mentioned second optical deflection device can be used in a laser radar system using all-solid-state scanning, as an optical deflection structure to achieve full-field coverage scanning, thereby increasing the detection distance and increasing the transmission power per unit field of view angle. The second optical deflection device 200 can further deflect the light beam emitted by the first optical deflection device 100, the first optical deflection device 100 performs fine deflection on the light beam, and the second optical deflection device performs coarse deflection. The first optical deflection device can also adopt an optical phased array (OPA), an acousto-optic deflector (AOD), an electro-optical deflection device (EOD), etc. Since the deflection angle of these deflection devices is only about 2-3 degrees, the second optical deflection device 200 is required to further expand the deflection angle or deflect in different directions to achieve coverage of the field of view area. The second optical deflection device 200 can adopt a liquid crystal optical deflection device.

[0298] In some optional embodiments, the light deflection unit 210, for example but not limited to, uses a liquid crystal polarization grating, which can deflect the outgoing light to a predetermined angle without amplifying the divergence angle of the incident light, and the angle range can reach plus or minus tens of degrees, so it is very suitable for expanding the scanning field of view. It can only deflect discrete angles and has a slow response speed, so the present application adopts a partitioning method for angle switching adjustment. Each light deflection unit 210 can deflect left-handed and right-handed circularly polarized light to two different angles, corresponding to the +1 and -1 diffraction order angles of the liquid crystal grating. By cascading N light deflection units 210, light deflection at 2N discrete angles is achieved.

[0299] The light deflection unit 210 includes a liquid crystal half-wave plate 214 and a liquid crystal polarization grating (LCPG) plate 216 ; the liquid crystal half-wave plate 214 includes electrodes disposed on two opposite sides and a half-wave plate liquid crystal layer 215 disposed between the electrodes on the two sides.

[0300] One side electrode of the liquid crystal half-wave plate 214 includes a plurality of first electrode blocks 211, and the other side electrode is a first whole electrode 213, each deflection sub-partition corresponds to at least one first electrode block 211; each deflection sub-partition 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one first electrode block 211, and a portion on the liquid crystal polarization grating 216 corresponding to the position of at least one first electrode block 211; or

[0301] The electrodes on both sides of the liquid crystal half-wave plate 214 include a plurality of first electrode blocks 211, two opposite first electrode blocks 211 form a first electrode pair 2110, and each deflection sub-area 2121 corresponds to at least one first electrode pair 2110; each deflection sub-area 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one first electrode pair 2110, and a portion on the liquid crystal polarization grating 216 corresponding to the position of at least one first electrode pair 2110;

[0302] The deflection angle of the light beam by the corresponding deflection sub-region 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflection sub-region 2121 in the liquid crystal half-wave plate 214 .

[0303] That is, the liquid crystal half-wave plate 214 in the light deflection unit 210 is provided with electrodes, and its electrodes can be divided into blocks on one side or on both sides, and the liquid crystal polarization grating 216 can be provided with electrodes or not, and these two situations are described below respectively.

[0304] In some optional embodiments, the liquid crystal polarization grating 216 is a passive liquid crystal deflection grating without electrodes. The light deflection unit 210 changes the deflection direction of the light beam passing through the passive liquid crystal deflection grating by adjusting the voltage applied to the electrodes on both sides of the liquid crystal half-wave plate 214. The deflection sub-areas 2121 of the light deflection unit 210 can be realized by forming a block structure of electrodes on one side or both sides of the liquid crystal half-wave plate 214. The required voltage can be applied to each electrode block respectively, so that the deflection angle of each deflection sub-area 2121 can be independently adjusted.

[0305] For the case where one side of the electrode is made into a block structure, see Fig.10a As shown. One side electrode of the liquid crystal half-wave plate 214 includes a plurality of first electrode blocks 211, and the other side electrode is a first whole electrode 213, and each deflection sub-partition 2121 corresponds to at least one first electrode block 211. Each deflection sub-partition 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one first electrode block, and a portion on the liquid crystal polarization grating 216 corresponding to the position of at least one first electrode block 211. The corresponding portion refers to the portion that is directly opposite in position, see Fig.10aAs shown in the dotted box, the portion corresponding to the position of at least one first electrode block 211 refers to the portion on the liquid crystal polarization grating plate 216 located in the same dotted box as the at least one first electrode block 211. In this case, each first electrode block 211 corresponds to a deflection sub-area 2121, and it can be changed that multiple first electrode blocks 211 correspond to one deflection sub-area 2121. The multiple first electrode blocks 211 include 2 or more first electrode blocks 211. The multiple first electrode blocks 211 can be arranged in a regular array, such as but not limited to a one-dimensional or two-dimensional array arrangement, or can be arranged in an irregular array.

[0306] For the case where the electrodes on both sides are made into block structures, see Fig.10b As shown, the electrodes on both sides of the liquid crystal half-wave plate 214 include a plurality of first electrode blocks 211, two opposite first electrode blocks form an electrode pair, each deflection sub-area 2121 corresponds to at least one electrode pair; each deflection sub-area includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one electrode pair, and a portion on the liquid crystal polarization grating 216 corresponding to the position of at least one electrode pair. The corresponding portions refer to the portions that are directly opposite in position, see Fig.10b As shown in the dotted box, the portion corresponding to the position of at least one electrode pair refers to the portion on the liquid crystal polarization grating plate 216 located in the same dotted box as the at least one electrode pair. Fig.10b In the figure, the electrode blocks corresponding to the two sides of the liquid crystal half-wave plate 214 are opposite to each other. However, these corresponding partition electrodes may not be strictly opposite to each other, and it is also acceptable for there to be a little misalignment between them. In this case, each electrode pair corresponds to a deflection sub-partition 2121, and it is also possible for multiple electrode pairs to correspond to one deflection sub-partition 2121. Multiple electrode pairs include situations where there are 2 or more electrode pairs. The multiple first electrode blocks 211 in each side electrode may be arranged in a regular array, for example but not limited to a one-dimensional or two-dimensional array arrangement, or may be arranged in an irregular array.

[0307] The deflection angle of the light beam by the corresponding deflection sub-region 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflection sub-region 2121 in the liquid crystal half-wave plate 214 .

[0308] In some optional embodiments, the light deflection unit 210 includes a liquid crystal half-wave plate 214 and a liquid crystal polarization grating plate 216, the liquid crystal half-wave plate 214 includes electrodes relatively arranged on two sides and a liquid crystal layer arranged between the electrodes on the two sides; the liquid crystal polarization grating plate 216 is an active liquid crystal polarization grating plate, the active liquid crystal polarization grating plate 216 includes electrodes relatively arranged on two sides and a grating liquid crystal layer 2164 arranged between the electrodes on the two sides, and the control device 600 needs to adjust the voltage applied to the electrodes of the liquid crystal half-wave plate 214 and the electrodes of the active liquid crystal polarization grating plate 216 accordingly to change the deflection angle of the light beam passing through; the deflection sub-area 2121 of the light deflection unit 210 can be realized by making one side or two sides of the liquid crystal half-wave plate 214 into a block structure, and making one side or two sides of the liquid crystal polarization grating plate into a block structure, and the required voltage can be applied to each electrode block respectively, so that the deflection angle of each deflection sub-area 2121 can be independently adjusted. In the light deflection unit 210 , the liquid crystal half-wave plate 214 further includes a first substrate 217 and a second substrate 218 which are arranged opposite to each other; the liquid crystal polarization grating plate 216 further includes a third substrate 2161 and a fourth substrate 2162 which are arranged opposite to each other.

[0309] The case where one side electrode of the liquid crystal polarization grating plate 216 is made into a block structure is similar to the case where one side electrode of the liquid crystal half-wave plate 214 is made into a block structure, and the case where both side electrodes of the liquid crystal polarization grating plate 216 are made into a block structure is similar to the case where both side electrodes of the liquid crystal half-wave plate 214 are made into a block structure, which will not be described in detail here. It should be noted that:

[0310] In a light deflection unit 210, the liquid crystal polarization grating 216 and the liquid crystal half-wave plate 214 can be selected to have one side electrode as a block structure; see Fig.10c As shown, one side electrode of the liquid crystal half-wave plate 214 includes a plurality of first electrode blocks 211, and the other side electrode is a first whole electrode 213; one side electrode of the liquid crystal polarization grating plate 216 includes a plurality of second electrode blocks 2163, and the other side electrode is a second whole electrode 2165; at least one second electrode block 2163 on the liquid crystal polarization grating plate 216 and at least one first electrode block 211 corresponding to a position on the liquid crystal half-wave plate 214 form a block group; each deflection sub-area 2121 corresponds to at least one block group, that is, each deflection sub-area 2121 corresponds to at least one first electrode block 211 of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode block 2163 of the liquid crystal polarization grating plate 216. Each deflection sub-area 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and a portion on the liquid crystal polarization grating plate 216 corresponding to the position of the block group.

[0311] In a light deflection unit 210, the liquid crystal polarization grating 216 and the liquid crystal half-wave plate 214 can be selected to have electrodes on both sides as a block structure. Fig.10d As shown, electrodes on both sides of the liquid crystal half-wave plate 214 include a plurality of first electrode blocks 211, and two opposite first electrode blocks 211 on the liquid crystal half-wave plate 214 form a first electrode pair 2110; electrodes on both sides of the liquid crystal polarization grating plate 216 include a plurality of second electrode blocks 2163, and two opposite second electrode blocks 2163 on the liquid crystal polarization grating plate 216 form a second electrode pair 2160; at least one second electrode pair 2160 on the liquid crystal polarization grating plate 216 and at least one first electrode pair 2110 corresponding to a position on the liquid crystal half-wave plate 214 form a block group; each deflection sub-partition 2121 corresponds to at least one block group, that is, each deflection sub-partition 2121 corresponds to at least one first electrode pair 2110 of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode pair 2160 of the liquid crystal polarization grating plate 216. Each deflection sub-partition 2121 includes a portion of the liquid crystal half-wave plate 214 corresponding to the position of the block group, and a portion of the liquid crystal polarization grating plate 216 corresponding to the position of the block group.

[0312] In an optical deflection unit 210, one side electrode of the liquid crystal polarization grating plate 216 can be selected to form a block structure, and the two side electrodes of the liquid crystal half-wave plate 214 can be selected to form a block structure. Two opposite first electrode blocks on the liquid crystal half-wave plate form a first electrode pair, and at least one second electrode block on the liquid crystal polarization grating plate 216 and at least one first electrode pair corresponding to the position on the liquid crystal half-wave plate 214 form a block group; each deflection sub-area 2121 corresponds to at least one block group, that is, each deflection sub-area 2121 corresponds to at least one first electrode pair of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode block of the liquid crystal polarization grating plate 216. Each deflection sub-area 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and a portion on the liquid crystal polarization grating plate 216 corresponding to the position of the block group.

[0313] In an optical deflection unit 210, electrodes on both sides of the liquid crystal polarization grating 216 can be selected to form a block structure, and electrodes on one side of the liquid crystal half-wave plate 214 can be selected to form a block structure, two opposite second electrode blocks on the liquid crystal polarization grating 216 form a second electrode pair, and at least one second electrode pair on the liquid crystal polarization grating 216 and at least one first electrode block corresponding to a position on the liquid crystal half-wave plate 214 form a block group; each deflection sub-area 2121 corresponds to at least one block group, that is, each deflection sub-area 2121 corresponds to at least one first electrode block of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode pair of the liquid crystal polarization grating 216. Each deflection sub-area 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and a portion on the liquid crystal polarization grating 216 corresponding to the position of the block group.

[0314] The deflection angle of the light beam by the corresponding deflection sub-partition 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflection sub-partition 2121 in the liquid crystal half-wave plate 214 and the voltage applied to the electrode corresponding to the deflection sub-partition 2121 in the liquid crystal polarization grating 216.

[0315] It should be noted that, in the case where the second optical deflection device 200 includes at least two optical deflection units 210, the deflection sub-partitions 2121 on at least two different optical deflection units 210 are arranged corresponding to each other. In this case, the multiple deflection sub-partitions 2121 at the positions belonging to different optical deflection units 210 that can form a deflection optical path can be adjusted simultaneously when the deflection angle is adjusted. At this time, it is necessary to adjust the voltages applied to the multiple deflection sub-partitions 2121 respectively to achieve this.

[0316] From another perspective, the multiple deflection sub-areas 2121 corresponding to the positions of different optical deflection units 210 that can form a deflection optical path can also be understood as a deflection sub-area 212 that can be separated from each other in structure. Each deflection sub-area 212 has a uniform deflection angle for the light beam, and can independently adjust the deflection angle of the light beam as a whole. The multiple deflection sub-areas 212 are arranged in sequence according to the deflection direction of the light beam at the first deflection angle. In other words, the deflection sub-areas include deflection sub-areas corresponding to the positions in at least one optical deflection unit; the deflection sub-areas 2121 in at least one optical deflection unit 210 included in a deflection sub-area 212 can form a deflection optical path. When a deflection sub-area 212 includes one optical deflection unit 210, the deflection sub-area 2121 in the one optical deflection unit 210 can form a deflection optical path. When a deflection sub-area 212 includes two optical deflection units, the deflection sub-areas 2121 in the two optical deflection units 210 can form a deflection optical path. When a deflection sub-area 212 includes a plurality of light deflection units 210, the deflection sub-areas 2121 in the plurality of light deflection units can form a deflection light path.

[0317] Optionally, a quarter wave plate may be provided before the first layer of liquid crystal half wave plate to change the polarization state of the incident light beam and convert the linearly polarized light emitted by the first light deflection device 100 into circularly polarized light.

[0318] The electrode is, for example but not limited to, an ITO electrode. The shape and arrangement of the electrode blocks depend on the shape of the light beam to be deflected and the change of its scanning position on the optical deflection unit 210. The incident light beam is a long strip light beam arranged along the second direction in length, and is scanned along the first direction on the optical deflection unit 210. Correspondingly, the electrode blocks are also long strips arranged along the second direction in length, and multiple electrode blocks are also arranged in parallel along the first direction. Different electrode blocks are arranged separately, so voltages can be applied independently to control the arrangement state of the corresponding part of the liquid crystal molecules in the partition.

[0319] Theoretically, in the same optical deflection device, the liquid crystal half-wave plates 214 belonging to different optical deflection units 210 may also have different ITO electrode structures, for example, the electrode structure of the liquid crystal half-wave plates 214 of a part of the optical deflection units 210 is divided into two sides, and the electrode structure of the liquid crystal half-wave plates 214 of another part of the optical deflection units 210 is divided into one side and one side is not divided. The liquid crystal polarization gratings 216 belonging to different optical deflection units may also have different ITO electrode structures, for example, the electrode structure of the liquid crystal polarization gratings 216 of a part of the optical deflection units 210 is divided into two sides, and the electrode structure of the liquid crystal polarization gratings 216 of another part of the optical deflection units 210 is divided into one side and one side is not divided.

[0320] See also Fig.10a , 10b , 10c and 10d, the liquid crystal half-wave plate 214 may further include a first substrate 217 and a second substrate 218 disposed opposite to each other, and electrodes on both sides are respectively disposed on inner surfaces of the first substrate 217 and the second substrate 218 facing each other, and the inner surfaces are, for example, planes. The liquid crystal polarization grating plate 216 also includes a third substrate 2161 and a fourth substrate 2162 disposed opposite to each other, and electrodes on both sides are respectively disposed on inner surfaces of the third substrate 2161 and the fourth substrate 2162 facing each other, and the inner surfaces are, for example, planes.

[0321] In some optional embodiments, the liquid crystal polarization gratings 216 of all the light deflection units 210 in the second light deflection device 200 are passive liquid crystal polarization gratings, or the liquid crystal polarization gratings 216 of all the light deflection units 210 in the second light deflection device 200 are active liquid crystal polarization gratings, or the liquid crystal polarization gratings 216 of some of the light deflection units 210 in the second light deflection device 200 are passive liquid crystal polarization gratings, and the liquid crystal polarization gratings 216 of some of the light deflection units 210 are active liquid crystal polarization gratings; the liquid crystal material of the liquid crystal layer can be, for example but not limited to, one of nematic phase liquid crystal and blue phase liquid crystal.

[0322] Taking the passive liquid crystal polarization grating as an example, the passive liquid crystal polarization grating does not need to apply voltage to change the liquid crystal arrangement when working. By selecting whether to apply voltage to the liquid crystal half-wave plate 214, the polarization state of the light beam passing through can be changed, thereby controlling the deflection direction of the light beam passing through the passive liquid crystal polarization grating. The deflection angle of the light beam by the passive liquid crystal polarization grating is preset, and the left-handed polarization component and the right-handed polarization component of the incident light beam will be deflected to the positive first-order diffraction direction and the negative first-order diffraction direction of the liquid crystal polarization grating. The angles of these two diffraction directions relative to the incident direction are equal, and the deflection directions are opposite. Therefore, by matching the light deflection unit with different light beam deflection angles and applying the corresponding voltage to the liquid crystal half-wave plate, it is possible to achieve deflection of the light beam at multiple different preset angles.

[0323] For each incident light beam of the first deflection angle changing along the first direction emitted by the first light deflection device 100, as the light beam starts to scan, the voltage applied to the scanned deflection partition in the second light deflection device 200 starts to be changed synchronously and sequentially, and the arrangement of the liquid crystal molecules in the scanned deflection partition is switched to the state required for the next light beam deflection angle. Thus, each deflection partition 212 can switch the liquid crystal arrangement state by using the gap between the first light deflection device 100 deflecting the light beam to scan other deflection partitions along the first direction. When the light beam deflected by the first light deflection device 100 scans the last deflection partition of the second light deflection device 200 in the deflection cycle, the arrangement of the liquid crystal molecules in the first deflection partition to be scanned in the next deflection cycle has been switched to the state required for the next light beam deflection angle. Therefore, at this time, the first light deflection device 100 can be immediately controlled to deflect the light beam along the first direction to the first deflection partition to be scanned to start scanning in the next deflection cycle without waiting. It can also be understood that the liquid crystal half-wave plate can update the arrangement state of the liquid crystal in real time by partitions along the scanning direction of the light beam thereon according to a preset frequency, so as to achieve seamless switching of the light beam deflection angle.

[0324] See also Fig.11a The figure shows a structural example of a second optical deflection device 200 using a passive liquid crystal polarization grating. Each optical deflection unit 210 in the second optical deflection device 200 adopts a binary cascade. Multiple optical deflection units are arranged in sequence along the propagation direction of the light beam, and the deflection angle of the passing light beam increases step by step in the order of arrangement in a natural number power of two. That is, the first optical deflection unit closest to the light incident side has the smallest deflection angle of the passing light beam, while the last optical deflection unit farthest from the light incident side and closest to the light exit side has the largest deflection angle of the passing light beam. Assuming that the deflection angle of the first optical deflection unit to the passing light beam is r, the deflection angles of the passing light beam of the N optical deflection units 210 arranged in sequence along the exit direction of the light beam are respectively Correspondingly, the entire second light deflection device 200 including N light deflection units can deflect the passing light beam by the preset deflection angles as follows: , it can be seen that the light beam deflection angle that the second light deflection device 200 can provide is an odd multiple of the minimum deflection angle r of a single light deflection unit for the passing light beam, and the maximum value of the odd number is two to the power of N minus one, where N is the number of light deflection units included in the second light deflection device 200. The angular interval between the preset deflection angles of adjacent levels is 2r, that is, the second light deflection device 200 has multiple preset deflection angles for the passing light beam distributed in an arithmetic progression according to the preset angular intervals, and the deflection accuracy of the passing light beam is 2r, and the angular interval can be regarded as the angular tolerance of the arithmetic progression. Therefore, the second deflection angle range of the passing light beam by the light deflection unit 210 based on the binary cascade is and the total number of different deflection angles that can be provided The relational expression is:

[0325] ,

[0326] ,

[0327] Wherein, r is the minimum deflection angle of the passing light beam in the N light deflection units, and N is the total number of the light deflection units 210 in the second light deflection device 200 .

[0328] During use, the polarization state of the light beam incident to the passive liquid crystal polarization grating 216 in the light deflection unit 210 can be selected by applying a voltage to the liquid crystal half-wave plate 214 in the light deflection unit 210, thereby correspondingly controlling the deflection direction of the light beam diffracted when passing through the passive liquid crystal polarization grating 216. For example, if the light beam is deflected in the direction of positive first-order diffraction after passing through the liquid crystal half-wave plate 214 to which a saturation voltage is applied and then passing through the passive liquid crystal polarization grating 216, then the light beam will be deflected in the direction of negative first-order diffraction after passing through the liquid crystal half-wave plate 214 to which no voltage is applied and then passing through the passive liquid crystal polarization grating 216. Since the polarization state of the light beam will also be changed while being diffracted by the passive liquid crystal polarization grating 216, if the light beam is to continue to be deflected to the same diffraction level in the next light deflection unit 210, it is necessary to turn off the voltage applied to the liquid crystal half-wave plate 214 in the next light deflection unit 210 so that the liquid crystal half-wave plate 214 changes the polarization state of the passing light beam back to the polarization state before the last deflection; if the light beam is to be deflected to the opposite diffraction level in the next light deflection unit 210, it is necessary to apply a saturation voltage to the liquid crystal half-wave plate 214 in the next light deflection unit 210 so that it does not change the polarization state of the passing light beam.

[0329] Fig.11b The figure is a schematic diagram of the relationship between the voltage control of the binary cascade light deflection unit 210 and the deflection angle of the one-dimensional deflection of the passing light beam. The shaded area in the figure indicates that a saturation voltage is applied to the corresponding liquid crystal half-wave plate 214, and the liquid crystal half-wave plate 214 does not change the polarization state of the passing light beam. The white area indicates that the saturation voltage applied to the liquid crystal half-wave plate 214 is turned off, and the corresponding liquid crystal half-wave plate 214 will change the polarization state of the passing light beam. Since the liquid crystal polarization grating plates are all passive, all the passive liquid crystal polarization grating plates 216 cannot be applied with voltage, and will deflect the passing light beam to a preset angle in the direction corresponding to the positive first or negative first diffraction according to the polarization state of the passing light beam. Fig.11bIn the example, the second light deflection device includes four light deflection units in binary cascade, each light deflection unit includes a liquid crystal half-wave plate and a passive liquid crystal polarization grating plate, and the light deflection units are arranged in the following order along the direction of the light beam: the first light deflection unit includes a liquid crystal half-wave plate I and a passive liquid crystal polarization grating plate I, the second light deflection unit includes a liquid crystal half-wave plate II and a passive liquid crystal polarization grating plate II, the third light deflection unit includes a liquid crystal half-wave plate III and a passive liquid crystal polarization grating plate III, and the fourth light deflection unit includes a liquid crystal half-wave plate IV and a passive liquid crystal polarization grating plate IV. Moreover, the passive liquid crystal polarization grating plates I-IV have the same grating vector direction. Among them, the deflection angles of the passive liquid crystal polarization grating plates I-IV to the light beam increase step by step in a natural number power of two, and the value of the natural number is the serial number of the light deflection unit minus one, corresponding to r, 2r, 4r and 8r. In practical applications, the deflection angle of each liquid crystal polarization grating plate to the light beam can be selected as needed.

[0330] See also Fig.11a and Fig.11b As shown, a reference system is established with the horizontal incident light beam as 0 degrees, the leftward deflection as a positive angle, and the rightward deflection as a negative angle. If the polarization state of the light beam when incident on the second light deflection device 200 will cause the passive liquid crystal polarization grating to deflect the light beam in the direction of the positive first-order diffraction and the light beam wants to obtain a deflection angle of +r after passing through the entire second light deflection device, the voltage of the liquid crystal half-wave plate I should be turned off so that the light beam passing through the liquid crystal half-wave plate I first changes its polarization state, so that the passive liquid crystal polarization grating I will deflect the passing light beam by -r and change the polarization state of the light beam back to the polarization state at the time of incidence. Since the passive liquid crystal polarization grating II and the passive liquid crystal polarization grating III need to be made to continue to deflect the light beam in the directions of -2r and -4r respectively, the voltages of the liquid crystal half-wave plate II and the liquid crystal half-wave plate III need to be turned off accordingly so that the light beam changes its polarization state before entering the corresponding passive liquid crystal polarization grating II and the passive liquid crystal polarization grating III. Finally, a saturation voltage is applied to the liquid crystal half-wave plate IV to maintain the polarization state of the light beam after passing through the passive liquid crystal polarization grating plate III, so that the light beam can be deflected back to +8r in the opposite direction to the previous direction when passing through the passive plate IV to finally obtain a deflection direction of r. Similarly, the second light deflection device 200 can also be configured as follows: Fig.11bThe voltage application method shown deflects the passing light beam to other preset deflection angles, such as the angles of 3r, 5r, 7r, 9r, 11r, 13r, 15r, -r, -3r, -5r, -7r, -9r, -11r, -13r, -15r in the figure, and by changing the voltage application conditions of the liquid crystal half-wave plates I-IV to adjust the polarization state of the light beam before entering the corresponding passive liquid crystal polarization grating plates I-IV, the light beam can be deflected to 16 different deflection angles through the cooperation of the four light deflection units 210. It can be understood that to achieve different numbers of deflection angles, different numbers of light deflection units 210 can be set to achieve this.

[0331] Fig.11c FIG. 2 is a schematic diagram showing the relationship between the voltage control of the binary cascade optical deflection unit 210 and the deflection angle of the two-dimensional deflection of the light beam passing through. Fig.11b The difference is that Fig.11b The four deflection units deflect the light beam in the same direction, such as horizontally or vertically. Fig.11c In the figure, one of the four deflection units deflects the light beam in the first direction, and three deflection units deflect the light beam in the second direction, where p represents the minimum deflection angle of the passing light beam in the vertical direction, and h represents the minimum deflection angle of the passing light beam in the horizontal direction. The four deflection units cooperate to achieve two deflection angles in the vertical direction and eight deflection angles in the horizontal direction, for example Fig.11c The angles shown in the figure are (-p, h), (p, h), (-p, 3h), (p, 3h), (-p, 5h), (p, 5h), (-p, 7h), (p, 7h), (-p, -7h), (p, -7h), (-p, -5h), (p, -5h), (-p, -3h), (p, -3h), (-p, -h), and (p, -h).

[0332] If an active liquid crystal polarization grating is used, the difference is that: the passive liquid crystal polarization grating does not need to apply voltage during operation, and the passive liquid crystal polarization grating only needs to apply corresponding voltage to the liquid crystal half-wave plate to achieve light beam deflection during operation, with fast response speed and simple driver; the active liquid crystal polarization grating needs to apply corresponding voltage corresponding to different deflection angles during operation, and the active liquid crystal polarization grating needs to adjust the voltage applied to the liquid crystal half-wave plate and the active liquid crystal polarization grating respectively during operation corresponding to different deflection angles. When an active liquid crystal polarization grating is used, the voltage applied to the liquid crystal half-wave plate and the active liquid crystal polarization grating in the light deflection unit 210 in the second light deflection device can be changed, and different deflection angles can be achieved by changing the applied voltage, which will not be described in detail here.

[0333] In some optional embodiments, in the above-mentioned second optical deflection device 200, the adjustment time of the second deflection angle of the incident light beam by the deflection partition adjustment is not greater than the time interval between two adjacent deflection cycles of the deflection partition being scanned by the incident light beam. In order to ensure that each deflection partition has enough time to adjust the deflection angle, the number of deflection partitions can be reasonably set within the duration of the deflection cycle. This is because when the number of deflection partitions is too small, it cannot be guaranteed that the time interval between two adjacent deflection cycles of each deflection partition being scanned by the incident light beam is sufficient to complete the deflection angle adjustment. Therefore, the number of deflection partitions is determined according to the number of second deflection angles deflected by the second optical deflection device 200, the time required for the second optical deflection device 200 to deflect light beams of multiple different first deflection angles to multiple different second deflection angles, and the adjustment time required for the second optical deflection device 200 to complete one deflection angle adjustment. In other words, the number of deflection partitions can be set according to the number of deflection angles of the second light deflection device, the required frame rate, and the time required for the second light deflection device to complete a deflection angle adjustment, so as to ensure that the deflection partition can complete the adjustment of the deflection angle within the interval between two scans while meeting the required frame rate. Specifically, the number D of deflection partitions 212 is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second light deflection device 200, F is the frame rate at which the second light deflection device 200 deflects a round of M deflection angles, and T is the time required for the second light deflection device 200 to complete a deflection angle adjustment. Of course, setting the number of deflection partitions according to this formula is a preferred method, which can make each deflection partition not need to wait, and can use the scanning interval to complete the angle change adjustment. Even if the number is set to be smaller, it can also reduce the waiting time to a certain extent.

[0334] The response speed of the liquid crystal half-wave plate 214 is about several milliseconds. The system is in an inoperative state during the adjustment of the liquid crystal switch state. In order to meet the requirement of a 10Hz frame rate for light scanning, a traversal of all scanning angles must be completed within 100ms. Therefore, in order to ensure the scanning efficiency of the system, the ITO electrode layer of the liquid crystal half-wave plate is divided into blocks, or the ITO electrode layer of the liquid crystal half-wave plate and the liquid crystal polarization grating is divided into blocks. When the light beam is scanned, the light beam is incident on one electrode block, and at this time, the remaining electrode blocks that are not incident on the light beam can be adjusted to change the phase delay amount.

[0335] Take the first light deflection device 100 deflecting the emitted light beam in the vertical direction as an example. Assuming that the liquid crystal response time is Sms, the combination of N light deflection units needs to achieve a total of multiple discrete angles of deflection. In this case, each light deflection unit needs to be divided into D deflection partitions along the vertical direction. Fig.12 , Fig.13 , Fig.14As shown, at the beginning of a frame (duration 100ms), the light beam enters the first deflection partition, and the beam width in the vertical direction is designed to be the width of one deflection partition. The first optical deflection device 100 makes the light beam quasi-continuously deflect downward, and the light beam begins to enter the second deflection partition. At this time, the first and second deflection partitions are in the "scanning" state, and the state of the liquid crystal molecules therein cannot be adjusted, while the remaining K-2 layers are in the "non-scanning" state. When the light beam leaves the first deflection partition and begins to enter the third deflection partition, the first deflection partition enters the "non-scanning" state, while the second and third deflection partitions are in the "scanning" state. According to the above rules, when the light beam enters the Dth deflection partition, a deflection cycle is completed. At this time, the first optical deflection device 100 deflects the light beam to enter the first deflection partition, and the second deflection cycle begins. A total of multiple deflection cycles are required in one frame, and in each deflection cycle, the second optical deflection device 200 deflects the light to one of a plurality of discrete angles.

[0336] See also Fig.12 , Fig.13 , Fig.14 As shown, in some embodiments, the light deflection unit 210 is divided into 1-D parallel arranged deflection partitions. Corresponding to each second deflection angle, the incident light beam with different first deflection angles is scanned from the 1st partition to the Dth deflection partition along the vertical direction. After the light beam deflected by the first light deflection device 100 leaves the first deflection partition and scans the second deflection partition, the scanned first deflection partition can begin to change the voltage applied to the first deflection partition through the corresponding independently set ITO electrode blocks, so as to switch the arrangement state of part of the liquid crystal molecules corresponding to the first deflection partition to the arrangement state of the liquid crystal molecules required for the next second deflection angle. That is to say, in the process of scanning the incident light beam from the second deflection partition to the Dth deflection partition, the arrangement state of part of the liquid crystal molecules corresponding to the first deflection partition can be synchronously changed through the corresponding ITO electrode blocks, and the whole process is sufficient to complete the change of the arrangement state of part of the liquid crystal molecules in the first deflection partition. Therefore, for a second deflection angle, when the incident light beam of the first deflection angle has been scanned from the 1st deflection partition to the Dth deflection partition, some liquid crystal molecules corresponding to the 1st deflection partition have completed the state change required for the next second deflection angle, the incident light beam can immediately and seamlessly start scanning the next second deflection angle again from the 1st deflection partition.

[0337] For example, to meet the scanning frame rate of 10HZ, Figure 2 and Figure 3A scan of all 16 second deflection angles needs to be completed within 100ms. The scanning time of each second deflection angle is 100 / 16=6.25ms. The optical deflection unit is divided into 10 deflection partitions, and the scanning time of each deflection partition is 6.25 / 10=0.625ms. As mentioned above, during the scanning of the current deflection partition and the next deflection partition, the liquid crystal state of the deflection partition cannot be changed. Therefore, for a deflection partition, the time for adjusting the deflection angle is 6.25-2*0.625=5ms. This period of time is equal to the adjustment time of the liquid crystal state during the switching of the next deflection angle. Therefore, 5ms can meet the requirements of seamless switching of deflection angles.

[0338] In the above description, the example is described that the light beam scans each deflection partition from top to bottom in sequence in one deflection cycle, and the light beam scans each deflection partition from top to bottom in sequence in the next deflection cycle. In actual applications, the scanning may not be performed in this order, and the scanning order may be randomly adjusted, for example: the light beam may not be incident in sequence from top to bottom. In addition, in one deflection cycle, the second deflection angle of each light beam deflected may be the same or different, as long as the entire field of view is covered in the end.

[0339] In the above-mentioned second optical deflection device 200, the optical deflection unit is divided into D deflection sub-partitions along the first direction, and the size of the optical deflection unit 210 in the first direction is greater than D*d_v, where d_v is the size of the light beam in the first direction at this time. Correspondingly, the size of the optical deflection unit in the second direction must satisfy the size of the light beam in the second direction included here.

[0340] In addition to LCPG, the second optical deflection device 200 may also use other suitable devices that can achieve coarse light beam deflection. As long as the optical deflection device is divided into a plurality of deflection partitions 212 and each deflection partition can independently adjust the deflection angle of the light beam, it is in line with the inventive concept of the present application. The second optical deflection device 200 is usually relatively thin, so when the incident light beam enters the optical deflection device, the beam path will not be affected by the thickness of the optical deflection device and can be approximately direct.

[0341] In some optional embodiments, the second light deflection device 200 further includes: a temperature regulator 240, which is configured to adjust the time for the second light deflection device to adjust the deflection angle by changing the temperature of the second light deflection device 200. In order to ensure that the liquid crystal molecular material in the liquid crystal polarization grating in the second light deflection device can work normally, it is necessary to control the temperature of the second light deflection device 200 so that it is within a certain temperature range. The temperature regulator can be used to control the temperature of the second light deflection device 200 within a preset temperature range. In addition, at different temperatures, the speed at which the liquid crystal molecules adjust their states is different, so that the time for each deflection partition to adjust the deflection angle is also different. Therefore, the time for the deflection partition to adjust the deflection angle can be changed by changing the temperature of the second light deflection device 200.

[0342] The second light deflection device 200 with a partition structure can synchronously refresh the arrangement of the liquid crystal molecules of the scanned deflection partition to the state required for the next second deflection angle by applying a change in voltage during the change of the incident position caused by the change of the first deflection angle of the incident light beam, so that the switching of the light beam deflection angle can be seamless without waiting. For the existing LCPG module, since a uniform voltage is applied to the liquid crystal half-wave plate through the entire ITO electrode, when the LCPG module switches the deflection angle of the light beam, it is necessary to change the voltage applied to the ITO electrode of the liquid crystal half-wave plate accordingly. This process requires waiting for the change of the arrangement state of the liquid crystal molecules, which takes a long time. Therefore, in the above-mentioned switching deflection angle process of the existing LCPG module, the entire system can only wait and cannot scan and detect.

[0343] In some optional embodiments, the incident light beam may be a strip light beam, and the second light deflection device 200 is configured as follows: when the incident light beam is a strip light beam: deflecting incident light beams of multiple different first deflection angles to the same second deflection angle to complete scanning of a corresponding scanning partition of the field of view; deflecting each first deflection angle of the light beams of multiple different first deflection angles to multiple different second deflection angles to complete scanning of multiple scanning partitions corresponding to different multiple second deflection angles. The scanning partition is rectangular, and the length of the light beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition.

[0344] It can be understood that in some embodiments, when the scanning of the entire field of view is completed, the angles and order of the light beams of the first deflection angle and the second deflection angle can be configured to first complete the scanning of one scanning area, then scan the next scanning area, and so on, to scan all scanning areas. That is, the incident light beams of multiple different first deflection angles can be deflected to the same second deflection angle within one deflection cycle to complete the scanning of a corresponding scanning partition in the field of view; the second deflection angles of the incident light beams of the multiple different first deflection angles are different in different deflection cycles, so that the scanning of a corresponding scanning partition is completed in one deflection cycle; after completing one scanning partition, the next deflection cycle scans the next scanning partition; thus, the scanning of multiple different scanning partitions can be completed correspondingly after multiple deflection cycles.

[0345] See also Figure 2 As shown, the entire field of view can be divided into multiple scanning partitions. Figure 2 16 scanning partitions are taken as an example, corresponding to the 16 grids in the figure. Different deflection partitions of the second light deflection device 200 deflect the received strip incident light to different second deflection angles so that it can be irradiated on different scanning partitions. One second deflection angle corresponds to one scanning partition. After multiple incident light beams of the first deflection angles are deflected to the second deflection angle, one scanning partition can be fully covered. 16 second deflection angles can correspond to 16 scanning partitions. See Figure 2 As shown, by deflecting 2 second deflection angles in the first direction and 8 second deflection angles in the second direction, it is possible to achieve Figure 2 The scanning of the 16 scanning partitions shown in the figure corresponds to each scanning partition and a second deflection angle, that is, after the multiple different first deflection angles deflected by the first light deflection device 100 are deflected to the same second deflection angle by the second light deflection device 200, they can cover a scanning partition. Among them, the scanning partition is rectangular, and the length of the strip light beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition. During actual scanning, in the first deflection period, multiple light beams with the first deflection angles can be deflected to the first second deflection angle to complete the scanning of the scanning partition corresponding to the first row and the first square; in the second deflection period, multiple light beams with the first deflection angles can be deflected to the second second deflection angle to complete the scanning of the scanning partition corresponding to the first row and the second square; ...; in the fourth deflection period, multiple light beams with the first deflection angles are deflected to the fourth second deflection angle, as shown in FIG. Figure 2 As shown, the scanning of the scanning partition corresponding to the fourth square in the first row is completed; and so on, after 16 deflection cycles, the scanning of all scanning partitions corresponding to the 16 squares is completed.

[0346] In some other embodiments, the second light deflection device 200 deflects incident light beams of multiple different first deflection angles to one of multiple different second deflection angles in one deflection cycle, respectively, and scans partial areas in corresponding scanning partitions respectively; wherein, in one deflection cycle, the second deflection angles at which incident light beams of multiple different first deflection angles are deflected are the same or different; and the second deflection angles at which incident light beams of each first deflection angle are deflected are different in different deflection cycles. In one deflection cycle, each incident light beam of multiple different first deflection angles is randomly deflected to one of multiple different second deflection angles, so that the second deflection angles at which incident light beams of all first deflection angles are deflected in one deflection cycle are the same, partially the same, partially different, or completely different from each other. Optionally, in one deflection cycle, at least two incident light beams of multiple different first deflection angles are deflected to different second deflection angles, so that the second deflection angles at which incident light beams of all first deflection angles are deflected in one deflection cycle are partially the same, partially different, or completely different from each other.

[0347] For example, in one deflection cycle, the deflected light beam incident at different first deflection angles can be deflected to two or more different second deflection angles respectively; in this case, in one deflection cycle, the scanning is no longer concentrated on one corresponding scanning subarea, but the scanning is performed in a jump manner on different positions along the first deflection angle in two or more different scanning subareas; in this way, after multiple deflection cycles, the scanning of all scanning subareas can also be completed. For example, in this embodiment, in one deflection cycle, the light beam formed after deflection at the second deflection angle corresponds to scanning subareas corresponding to different second deflection angles, and the scanned positions are spaced far apart from each other, which can reduce the mutual crosstalk between two adjacent scans.

[0348] See also Figure 3As shown, the entire field of view can be divided into multiple scanning partitions, and the number of scanning partitions is 16, corresponding to the 16 grids in the figure. In one deflection cycle, the second optical deflection device 200 can deflect multiple light beams of the first deflection angle to different second deflection angles so as to alternately scan different scanning partitions. For example, in the first deflection cycle, the second optical deflection device 200 deflects the first light beam of the first first deflection angle to the first second deflection angle, and scans a small strip area in the first square of the first row; deflects the second light beam of the second first deflection angle to the second second deflection angle, and scans a small strip area in the second square of the first row; ... In the second deflection cycle, the second optical deflection device 200 deflects the first light beam of the first first deflection angle to the first second deflection angle, and scans a small strip area in the second square of the first row; deflects the second light beam of the second first deflection angle to the second second deflection angle, and scans a small strip area in the third square of the first row; .... By analogy, the scanning area corresponding to each square is cross-scanned, and after multiple deflection cycles, the scanning of all scanning partitions corresponding to all squares is completed. With this setting, the two scanning areas corresponding to the scanning in the field of view in two adjacent deflection cycles can be far apart, and the photosensitive pixels used by the receiving module to sense the two corresponding scanning areas in these two adjacent scanning periods are also far apart, which can reduce the crosstalk between these photosensitive pixels working successively.

[0349] Compared with the case of scanning with a circular or nearly circular spot, using a long light beam to scan the field of view and making the first light deflection device (such as AOD) deflect the light beam in the width direction of the light beam can greatly reduce the number of angles of deflection of the second light deflection device (such as LCPG) in the first direction and the second direction, for example Figure 2 and Figure 3 As shown, the deflection is at 16 angles, 8 angles in the horizontal direction and 2 angles in the vertical direction. The number of angles deflected by the second optical deflection device 200 is related to the number of layers it contains (i.e., the number of optical deflection units in the optical deflection device). Therefore, the number of layers of the second optical deflection device 200 can also be reduced. For example, when the deflection is at 16 angles, the second optical deflection device 200 only needs four layers, and the second optical deflection device 200 can be made thinner and smaller in size.

[0350] The scanning partition is rectangular, and the length of the strip beam after being deflected by the second deflection angle is equal to the length of one direction of the scanning partition, for example Figure 2 and Figure 3The length of the strip light beam after deflection by the second deflection angle is equal to the length of the scanning partition in the second direction. The long side of the strip light emitted from the first optical deflection device 100 is perpendicular to the light deflection direction of the first optical deflection device 100, so that compared with the block-shaped scanning light, under the same total power, the light beam deflected by the second deflection angle can cover a larger field of view. Therefore, the second optical deflection device 200 can cover a larger overall field of view by deflecting fewer different angles. This makes the number of layers of the second optical deflection device 200 (that is, the number of optical deflection units 210) required less, the cost is lower, and the response speed is faster.

[0351] The above-mentioned transmitting module can be applied to the field of depth sensing technology, for example, but not limited to, for a laser radar system using all-solid-state scanning, as a light deflection structure to achieve coverage scanning of the entire field of view, thereby increasing the detection distance and increasing the transmission power per unit field of view angle. It can also be used in the fields of high-speed photography, optical engineering, space optical communication, non-destructive testing, optical sensing technology, optical multi-mode guidance technology, magneto-optical recording technology, magneto-optical imaging technology, laser display technology, precision optical instruments, etc. The second light deflection device 200 in the transmitting module can further deflect the light beam emitted by the first light deflection device 100, the first light deflection device 100 finely deflects the light beam, and the second light deflection device 200 performs coarse deflection. The first light deflection device 100 can also adopt an optical phased array (OPA), an acousto-optic deflection device (AOD), an electro-optical deflection device (EOD), etc. Since the deflection angle of these deflection devices is only about 2-3 degrees, the second light deflection device 200 is required to further expand the deflection angle or deflect in different directions to achieve coverage of the field of view area. The second light deflection device 200 may be a liquid crystal light deflection device.

[0352] In some optional embodiments, the control device 600 of the above-mentioned emission module can be an independent device, and the control of the first light deflection device 100 and the second light deflection device 200 is realized by an independent device. The control device 600 can also be a discrete device, see Figure 6 As shown, it includes a first control unit 110 and a second control unit 230;

[0353] The first control unit 110 is used to control the first optical deflection device 100 to deflect a plurality of different first deflection angles in a deflection period, and to make the incident light beam of each first deflection angle incident on the corresponding deflection partition of the second optical deflection device 200; the first control unit 110 can be set separately or integrated with the first optical deflection device.

[0354] The second control unit 230 is used to control the multiple deflection partitions 212 to receive the incident light beam in time division and deflect the incident light beam to the required second deflection angle, and control the deflection partitions 212 to pre-adjust their deflection angles to the light beam before being scanned by the incident light beam; wherein, after the current deflection period is scanned by the incident light beam, the deflection angle of at least one deflection partition 212 to the incident light beam is adjusted to the second deflection angle required for the next deflection period before the next deflection period is scanned by the incident light beam. The second control unit 230 can be provided separately or integrated with the second light deflection device.

[0355] In some optional embodiments, the apparatus further comprises a temperature regulator 240 configured to adjust the time for the second light deflection device to adjust the deflection angle by changing the temperature of the second light deflection device 200. The temperature regulator 240 can be provided separately or integrated with the second light deflection device.

[0356] The above-mentioned light deflection unit 210 with a partition structure can synchronously refresh the arrangement of the liquid crystal molecules of the scanned deflection partition to the state required for the next second deflection angle by applying a change in voltage during the change of the incident position caused by the change of the first deflection angle of the incident light beam, so that the switching of the light beam deflection angle can be seamless without waiting. For the existing LCPG module, since a uniform voltage is applied to the liquid crystal half-wave plate through the entire ITO electrode, when the LCPG module switches the deflection angle of the light beam, it is necessary to change the voltage applied to the ITO electrode of the liquid crystal half-wave plate accordingly. This process requires waiting for the change of the arrangement state of the liquid crystal molecules, which takes a long time. Therefore, in the above-mentioned switching deflection angle process of the existing LCPG module, the entire system can only wait and cannot scan and detect.

[0357] Embodiment 3

[0358] The transmission module provided in the third embodiment of the present invention has a structural diagram as shown in Fig.15 As shown. The difference from the transmitting module provided in the second embodiment is that in this third embodiment, the second optical deflection device 200 does not adopt a partition structure. At this time, the light beam deflected by the first optical deflection device 100 is expanded by the expansion device 500 and projected to the corresponding position of the second optical deflection device. Since the second optical deflection device is not partitioned, within a deflection cycle, the first optical deflection device deflects multiple light beams with first deflection angles in the first direction, and the deflected second deflection angles are generally the same, so as to avoid the waiting time for angle switching. One deflection cycle corresponds to the completion of the scan of one scanning area; the next deflection cycle continues to complete the scan of the next scanning area. After one deflection cycle is completed and before the next deflection cycle begins, it may be necessary to wait for a certain time to complete the adjustment of the deflection angle.

[0359] Optionally, in order to reduce the waiting time for adjusting the deflection angle in the third embodiment, the temperature of the second light deflection device can be adjusted to speed up the switching time of the liquid crystal molecule arrangement state. Blue phase liquid crystal with a faster response speed can also be used to speed up the angle switching time.

[0360] Embodiment 4

[0361] The transmitting module provided in the fourth embodiment of the present invention has a structural diagram as shown in Fig.16 As shown, the difference from the transmitting module in the second embodiment is that the deflection expanding device 500 is arranged at the light output side of the second light deflection device 200 to expand the light beam deflected by the second light deflection device 200.

[0362] Disposing the polarization expander 500 behind the second optical deflection device 200 makes the second optical deflection device 200 close to the first optical deflection device 100, which is beneficial to shortening the optical path length. At the same time, it makes the size of the light beam reaching the second optical deflection device 200 smaller, so that the size of the second optical deflection device can be smaller, which is also beneficial to the miniaturization of the entire module.

[0363] Embodiment 5

[0364] The transmitting module provided in the fifth embodiment of the present invention has a structural diagram as shown in Fig.17 As shown, the difference from the transmitting module in the third embodiment is that the deflection expanding device 500 is arranged at the light output side of the second light deflection device 200 to expand the light beam deflected by the second light deflection device 200.

[0365] Disposing the polarization expander 500 behind the second optical deflection device 200 makes the second optical deflection device 200 close to the first optical deflection device 100, which is beneficial to shortening the optical path length. At the same time, it makes the size of the light beam reaching the second optical deflection device 200 smaller, so that the size of the second optical deflection device can be smaller, which is also beneficial to the miniaturization of the entire module.

[0366] In the emission module provided by the embodiment of the present invention, the light beam emitted by the light source is a strip light beam, and the AOD is used as a one-dimensional fine scanning device. The AOD requires the incident light beam to have a high degree of collimation in the direction of light deflection, and the collimation requirement for the incident light beam in the direction perpendicular to the light deflection is relatively low. Therefore, the AOD can make the outgoing light beam appear as a strip light that is narrow in the direction of light deflection and wide perpendicular to the direction of light deflection in the far field. This is more in line with the luminescence characteristics of the current mainstream high-power semiconductor laser source: the beam parameter product (BPP) of the high-power laser light source spliced ​​by multiple light-emitting units (such as semiconductor EEL light sources) in the fast axis direction, that is, the product of the waist radius and the divergence angle is much smaller than the BPP in the slow axis direction. After the incident AOD is collimated by the lens, it can be collimated into shapes with similar sizes in the light deflection direction A and perpendicular to the light deflection direction B, and the divergence angle A is much smaller than the divergence angle B, matching the characteristics of the AOD.

[0367] On this basis, LCPG is subsequently used as a coarse scanning device in AOD, and the light beam emitted from AOD is deflected at a larger angle in time. For each angle to which LCPG is deflected, AOD performs fine scanning near this angle to achieve coverage of a broadband field of view. In this process, the long side of the strip light beam emitted from AOD is perpendicular to the light deflection direction of AOD, so that compared with block-shaped scanning light, under the same total power, the field of view angle covered by AOD scanning is larger. Therefore, LCPG only needs to deflect fewer different angles to cover a larger overall field of view. This requires fewer LCPG layers, lower costs, and faster response speeds.

[0368] The embodiment of the present invention further provides a laser radar system, the structure of which is as follows: Fig.18 As shown, it includes a receiving module 2 and the above-mentioned transmitting module 1, and the receiving module 2 is configured to sense the optical signal from the field of view range and obtain the three-dimensional information of the field of view range by processing and analyzing the optical signal.

[0369] An embodiment of the present invention also provides an electronic device, including the above-mentioned laser radar system. The laser radar system is a planar laser radar system with high frame rate, large field of view and long-distance ranging capability, which can realize a full solid-state scanning solution. When the AOD is used as the first light deflection device, the advantages of the AOD's fast response speed and high number of resolvable points are utilized to realize high-resolution rapid scanning. The AOD is combined with the LCPG array, and the advantages of the LCPG's high diffraction efficiency and large deflection angle are utilized to realize large-angle and long-distance ranging, and the requirements of the scanning frame rate can be met.

[0370] The embodiment of the present invention also provides a laser radar scanning method, the process of which is as follows: Fig.19 As shown, the following steps are included:

[0371] S101: A first light deflection device deflects a light beam emitted by a light source along a first direction by a plurality of first deflection angles to achieve a first level of light deflection. The length of the light beam along the first direction is less than the length along the second direction.

[0372] In this step, the control device can be used to control the first light deflection device to deflect the light beam to a plurality of different first deflection angles in a preset order in a time-sharing manner within a deflection period.

[0373] The deflection period is the time required for the first light deflecting device to deflect the incident light beam by all of the multiple different first deflection angles, or the deflection period is the time required for the first light deflecting device to deflect the incident light beam by a specified portion of the first deflection angles.

[0374] In a deflection period, a plurality of different first deflection angles of the light beam vary from large to small, or from small to large, or vary according to a preset random rule in each deflection direction.

[0375] S102: The second light deflection device deflects the light beam after the first-level light deflection by multiple second deflection angles along the first direction and the second direction to achieve second-level light deflection and project a scanning light beam; the length of the scanning light beam in the first direction is less than its length in the second direction.

[0376] S103: Adjust the second deflection angle of the incident light beam by the second light deflection device by controlling the voltage applied to the second light deflection device, and fine-tune the corresponding applied working voltage according to the incident angle of the light beam incident on the second light deflection device; wherein, for the same second deflection angle, different incident angles correspond to different working voltages.

[0377] The above step S103 may be performed synchronously during the process of deflecting the light beam at each second deflection angle in step S102 or before deflecting the light beam.

[0378] In this step, the second light deflecting device may be controlled by the control device to deflect the light beam.

[0379] In some embodiments, the second light deflection device is a liquid crystal polarization grating, the liquid crystal polarization grating includes a liquid crystal half-wave plate and a liquid crystal polarization grating plate arranged in pairs, and the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating plate is a nematic phase liquid crystal or a blue phase liquid crystal. The operating voltage applied to the second light deflection device includes the voltage applied to the liquid crystal half-wave plate and / or the voltage applied to the liquid crystal polarization grating plate, the incident angle of the light beam incident on the second light deflection device is the angle difference between the incident direction of the light beam and the direction perpendicular to the light incident surface of the second light deflection device, and the operating voltage is positively correlated with the incident angle.

[0380] In some embodiments, the fine-tuning of the applied operating voltage according to the incident angle of the light beam incident on the second light deflection device includes: determining the optimal operating voltage applied to the liquid crystal half-wave plate corresponding to different incident angles according to the incident angle and total light intensity when the light beam is incident on the liquid crystal half-wave plate, the thickness of the liquid crystal half-wave plate and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate.

[0381] In some embodiments, for the same second deflection angle of the second light deflection device, the amplitude of the operating voltage applied to the second light deflection device is adjusted according to the incident angle of the light beam incident on the second light deflection device to compensate for the phase delay at different incident angles.

[0382] In some embodiments, the light beam emitted by the light source is a strip light beam with an aspect ratio of 20:1 to 100:1; the light beam incident on the first light deflection device has an aspect ratio of 3:1 to 1:2; and the scanning light beam is a strip light beam with an aspect ratio of 20:1 to 80:1.

[0383] Optionally, the aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident to the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 75:1; or optionally, the aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident to the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 25:1.

[0384] In some embodiments, the method further comprises: before performing the first-order light deflection, collimating the light beam; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction.

[0385] Among them, collimating the light beam includes: collimating the light beam with an aspect ratio of A in a first direction with a first collimation index, and collimating it in a second direction with a second collimation index, to collimate a light beam with an aspect ratio of B, wherein A>B, and the first collimation index is higher than the second collimation index; accordingly, the first optical deflection device and the second optical deflection device perform secondary deflection on the collimated light beam with an aspect ratio of B, to project a light beam with an aspect ratio of C, and C>B.

[0386] In some embodiments, the collimator collimates the light beam, including:

[0387] One cylindrical lens collimates the incident light beam along a first direction, and another cylindrical lens collimates the incident light beam along a second direction; or

[0388] A spherical lens collimates the incident light beam in a first direction and a second direction simultaneously; or

[0389] A cylindrical lens collimates the light beam along a first direction, and a spherical lens collimates the light beam along the first direction and the second direction at the same time.

[0390] In some embodiments, the following relationship is satisfied among the light emitting width V1 of the light source in the first direction, the divergence angle θ1 of the light emitted by the light source in the first direction, the beam waist diameter V2 in the first direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the first direction when the light beam is incident on the first light deflection device, and the focal length F2 of the collimating lens that collimates the light beam along the first direction: θ2= V1 / F2, θ2 V2=θ1 V1.

[0391] The following relationship is satisfied between the light emitting length H1 of the light source in the second direction, the divergence angle θ1 of the light emitting in the second direction, the beam waist diameter H2 in the second direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the second direction when the light beam is incident on the first light deflection device, and the focal length F1 of the collimating lens that collimates the light beam along the second direction: θ2= H1 / F1, θ2 H2=θ1 H1.

[0392] In some embodiments, the above method further includes: amplifying the deflection angle of the deflected light beam along the corresponding deflection direction by a preset multiple, and amplifying the divergence angle of the light beam by a corresponding preset multiple to form a strip light beam.

[0393] In some embodiments, the divergence angle of the strip light beam along the second direction is greater than or equal to the angular interval between two adjacent second deflection angles along the second direction when the second-level light deflection is performed.

[0394] In some embodiments, the deflection angle range of the plurality of first deflection angles deflected along the first direction when performing the first-level light deflection is greater than or equal to the angle interval between two adjacent second deflection angles along the first direction when performing the second-level light deflection.

[0395] In some embodiments, the deflection accuracy of the light beam deflecting the first deflection angle is higher than the deflection accuracy of the light beam deflecting the second deflection angle.

[0396] In some embodiments, the light beam is deflected at a plurality of first deflection angles and a second deflection angle to scan a preset field of view, wherein a length of the field of view in a first direction is smaller than a length in a second direction.

[0397] In some embodiments, a divergence angle of the collimated light beam after collimation in the first direction is less than 1 / 10 of a divergence angle of the collimated light beam after collimation in the second direction.

[0398] In some embodiments, the method further includes: the polarization expansion device amplifies the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in the corresponding deflection direction by a preset multiple. The process may include: at least one polarization expansion lens amplifies the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in at least one of the first direction and the second direction perpendicular to each other by a preset multiple. Specifically:

[0399] When the polarization expansion device includes two groups of cylindrical lenses, the first polarization expansion lens group magnifies the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in the first direction by a preset multiple, the first polarization expansion lens group includes a first polarization expansion cylindrical lens and a second polarization expansion cylindrical lens, and the preset multiple is the ratio of the focal length of the first polarization expansion cylindrical lens to the focal length of the second polarization expansion cylindrical lens; the second polarization expansion lens group magnifies the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in the second direction by a preset multiple, the second polarization expansion lens group includes a third polarization expansion cylindrical lens and a fourth polarization expansion cylindrical lens, and the preset multiple is the ratio of the focal length of the third polarization expansion cylindrical lens to the focal length of the fourth polarization expansion cylindrical lens;

[0400] When the polarization expansion device includes two spherical lenses, the first polarization expansion spherical lens and the second polarization expansion spherical lens amplify the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in the first direction and the second direction by a preset multiple, and the preset multiple is the ratio of the focal length of the first polarization expansion spherical lens to the focal length of the second polarization expansion spherical lens.

[0401] In some embodiments, the above method also includes: amplifying the divergence angle of the light beam deflected by the first light deflection device or the second light deflection device in the corresponding deflection direction by a preset multiple, and the divergence angle magnification factor is the same as the deflection angle magnification factor of the deflected light beam in the deflection direction.

[0402] In some embodiments, in the above step S103, when the second optical deflection device adopts a partition structure, the control device controls multiple deflection partitions 212 in the second optical deflection device 200 to receive deflected light beams corresponding to light beams with multiple different first deflection angles; each deflection partition 212 can adjust the deflection angle of the light beam individually; controls the currently scanned deflection partition 212 to deflect the light beam to the required second deflection angle; and controls at least one deflection partition 212 that is not currently scanned to adjust the deflection angle of the light beam to the second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the light beam and before the next deflection cycle is scanned by the light beam.

[0403] When the first light deflection device 100 deflects a plurality of light beams with different first deflection angles in time division, the plurality of deflection sub-areas 212 are controlled to receive a plurality of light beams with different first deflection angles in time division. The above-mentioned control of at least one deflection sub-area that is not currently scanned to adjust the deflection angle of the light beam to the second deflection angle required for the next deflection period after the light beam scanning in the current deflection period ends and before the light beam scanning in the next deflection period begins includes: after determining that a deflection sub-area has completed the light beam deflection in the current deflection period and is in a non-scanning state, controlling the deflection sub-area to adjust its deflection angle for the light beam, and before the next deflection period enters a scanning state, adjusting its deflection angle for the light beam to the second deflection angle required for the next deflection period.

[0404] Optionally, if a deflection partition is the deflection partition currently scanned by the light beam, it is determined that the deflection partition is in a scanning state, otherwise, it is determined that the deflection partition is in a non-scanning state; or if a deflection partition is the deflection partition currently scanned by the light beam or the next deflection partition to be scanned, it is determined to be in a scanning state, otherwise, it is determined that the deflection partition is in a non-scanning state.

[0405] Further optionally, when the deflection partition currently scanned by the light beam and the next deflection partition to be scanned are determined as deflection partitions in a scanning state, and the remaining deflection partitions are determined as deflection partitions in a non-scanning state, the deflection partition currently scanned by the light beam and the next deflection partition to be scanned are adjacent deflection partitions in position.

[0406] In some embodiments, the multiple second deflection angles for light beam deflection in one deflection period are all the same, or all different, or some are the same and some are different. A deflection subarea can sequentially receive one, two or more incident light beams with different first deflection angles in one deflection period. The multiple deflection subareas are configured to have the multiple second deflection angles for light beam deflection in one deflection period be the same, or all different, or some are the same and some are different.

[0407] In some embodiments, the number of light beams that can be received by each deflection partition is the same, different, or partially the same and partially different; accordingly, the widths of the multiple deflection partitions are the same, different, or partially the same and partially different.

[0408] In some embodiments, the voltage applied to the electrodes of each deflection partition is controlled to adjust the refractive index of the medium in the deflection partition to the light beam, so as to adjust the deflection angle of the light beam by the deflection partition. In the case where the second light deflection device adopts a liquid crystal polarization grating, the voltage applied to the electrodes of each deflection partition is controlled to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating, so as to change the second deflection angle of the light beam by the deflection partition.

[0409] Optionally, the second optical deflection device includes at least one optical deflection unit, the optical deflection unit includes a plurality of deflection sub-partitions, and when the deflection sub-partitions include deflection sub-partitions corresponding to positions in the at least one optical deflection unit, the voltages on the electrodes at both ends of each deflection sub-partition are respectively controlled, and the deflection angle of the light beam by at least one deflection sub-partition is changed by changing the voltages on the electrodes at both ends of at least one deflection sub-partition, so as to achieve a second deflection angle of the light beam by the corresponding deflection sub-partition.

[0410] Optionally, the second optical deflection device includes at least two optical deflection unit groups, each optical deflection unit group includes at least one of the optical deflection units; the control of the second deflection angle required for deflecting the light beam by the currently scanned deflection sub-partition includes: the second deflection angle required for deflecting the light beam in the first direction by the currently scanned deflection sub-partition of the light deflection unit in at least one optical deflection unit group, and / or the second deflection angle required for deflecting the light beam in the second direction by the currently scanned deflection sub-partition of the light deflection unit in at least one optical deflection unit group, wherein the first direction is perpendicular to the second direction.

[0411] In some embodiments, the time for adjusting the second deflection angle of the light beam by adjusting the deflection partition is no longer than the time interval between two adjacent scans of the deflection partition by the light beam.

[0412] In some embodiments, the number of deflection partitions is determined according to the number of second deflection angles deflected by the second optical deflection device, the time required for the second optical deflection device to deflect light beams of multiple different first deflection angles to multiple different second deflection angles, and the adjustment time required for the second optical deflection device to complete one deflection angle adjustment. Optionally, the number D of deflection partitions is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second optical deflection device, F is the frame rate at which the second optical deflector deflects a round of M deflection angles, and T is the time required for the second optical deflection device to complete one deflection angle adjustment.

[0413] In some embodiments, the following control processes are performed in parallel: controlling a currently scanned deflection partition in the second light deflection device to deflect the light beam, and controlling at least one currently unscanned deflection partition to adjust its deflection angle of the light beam.

[0414] In some embodiments, the field of view of the light scanning is divided into multiple scanning partitions, the scanning partitions are rectangular, and the incident light beam is a strip light beam; scanning the field of view includes: deflecting multiple light beams with different first deflection angles to the same second deflection angle to complete the scanning of a corresponding scanning partition in the field of view; deflecting each light beam with a first deflection angle in the multiple light beams with different first deflection angles to multiple different second deflection angles to complete the scanning of multiple scanning partitions corresponding to the different multiple second deflection angles; the length of the light beam after deflection by the second deflection angle is equal to the length of the scanning partition in one direction.

[0415] Optionally, within a deflection cycle, a plurality of light beams with different first deflection angles are deflected to the same second deflection angle to complete scanning of a corresponding scanning subarea in the field of view; each deflection cycle corresponds to completing different second deflection angles; and different deflection cycles deflect the light beams with the plurality of different first deflection angles at different second deflection angles;

[0416] Optionally, within one deflection period, light beams with multiple different first deflection angles are respectively deflected to one of multiple different second deflection angles to respectively scan partial areas in corresponding scanning partitions; wherein, within one deflection period, light beams with multiple different first deflection angles are deflected to the same or different second deflection angles; and light beams with each first deflection angle are deflected to different second deflection angles in different deflection periods.

[0417] In some embodiments, the above method further comprises: changing the temperature of the second light deflection device to adjust the time for the second light deflection device to adjust the deflection angle.

[0418] The above-mentioned method of the embodiment of the present invention, wherein the relevant contents have been described in detail in the relevant parts of the above-mentioned transmitting module, laser radar system and related electronic equipment, will not be repeated here.

[0419] like Fig. 20 As shown, an embodiment of the present invention further provides a computer-readable storage medium, which can be applied to the above-mentioned laser radar system. The computer-readable storage medium stores program data and can be executed by a processor to implement the laser radar scanning method recorded in each embodiment as described above.

[0420] The computer-readable storage medium may include a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc., which can store program instructions, or it may be a server storing the program instructions, which can send the stored program instructions to other devices for execution, or it can also execute the stored program instructions itself.

[0421] In the above description of the embodiments of the present invention, when multiple are involved, it should be understood to include two or more.

[0422] Unless otherwise specifically stated, terms such as processing, computing, calculating, determining, displaying, etc. may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, which operate and convert data represented as physical (e.g., electronic) quantities within registers or memories of a processing system into other data similarly represented as physical quantities within memories, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0423] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of protection of the present disclosure. The attached method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0424] In the above detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that the embodiments of the claimed subject matter require more features than are clearly stated in each claim. On the contrary, as reflected in the appended claims, the invention is in a state of having less than all the features of the disclosed individual embodiments. Therefore, the appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0425] Those skilled in the art will also appreciate that the various illustrative logic blocks, modules, circuits, and algorithmic steps described in conjunction with the embodiments herein can all be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, various illustrative components, blocks, modules, circuits, and steps are generally described above around their functions. Whether such functions are implemented as hardware or software depends on specific applications and the design constraints imposed on the entire system. A skilled person can implement the described functions in an alternative manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of the present disclosure.

[0426] The steps of the method or algorithm described in conjunction with the embodiments herein may be directly embodied as hardware, a software module executed by a processor, or a combination thereof. The software module may be located in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a mobile disk, a CD-ROM, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and the storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and the storage medium may also be present in a user terminal as discrete components.

[0427] If the methods or functions described in the above embodiments are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) or a processor to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

[0428] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it should be recognized by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, the word is covered in a manner similar to the term "including", just as "including," is explained as a transitional word in the claims. In addition, any term "or" used in the specification of the claims is intended to mean "non-exclusive or".

Claims

1. A laser radar scanning method, characterized in that: include: The first light deflection device deflects the light beam emitted by the light source along a first direction by a plurality of first deflection angles to achieve a first level of light deflection; the length of the light beam emitted by the light source along the first direction is shorter than the length along the second direction; The second light deflection device deflects the light beam deflected by the first light deflection device by a plurality of second deflection angles in the first direction and the second direction to achieve second-level light deflection, and projects a scanning light beam to scan a preset field of view, wherein the length of the field of view in the first direction is smaller than the length in the second direction; and the length of the scanning light beam in the first direction is smaller than the length in the second direction; The second deflection angle of the incident light beam deflected by the second light deflection device is adjusted by controlling the working voltage applied to the second light deflection device, and the corresponding applied working voltage is fine-tuned according to the incident angle of the light beam incident on the second light deflection device; wherein, for the same second deflection angle, different incident angles correspond to different working voltages.

2. The method according to claim 1, characterized in that The second light deflection device is a liquid crystal polarization grating, which includes a liquid crystal half-wave plate and a liquid crystal polarization grating plate arranged in pairs, and the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating plate is nematic liquid crystal or blue phase liquid crystal.

3. The method according to claim 2, characterized in that The working voltage applied to the second light deflection device includes the voltage applied to the liquid crystal half-wave plate and / or the voltage applied to the liquid crystal polarization grating. The incident angle of the light beam incident on the second light deflection device is the angle difference between the incident direction of the light beam and the direction perpendicular to the light incident surface of the second light deflection device. The working voltage is positively correlated with the incident angle.

4. The method according to claim 2, characterized in that The step of fine-tuning the corresponding applied operating voltage according to the incident angle of the light beam incident on the second light deflection device comprises: According to the incident angle and total light intensity of the light beam when it enters the liquid crystal half-wave plate, the thickness of the liquid crystal half-wave plate and the tilt angle of the liquid crystal molecules in the liquid crystal half-wave plate, the optimal operating voltage applied to the liquid crystal half-wave plate corresponding to different incident angles is determined.

5. The method according to claim 1, characterized in that The light beam emitted by the light source is a strip light beam with an aspect ratio of 20:1 to 100:1; the light beam incident on the first light deflection device has an aspect ratio of 3:1 to 1:2; and the scanning light beam is a strip light beam with an aspect ratio of 20:1 to 80:

1.

6. The method according to claim 1, characterized in that Also includes: Before the first-order light deflection is performed, the light beam is collimated; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction; and the first direction is perpendicular to the second direction.

7. The method according to claim 6, characterized in that The following relationship is satisfied among the light width V1 of the light source in the first direction, the divergence angle θ1 of the light source in the first direction, the beam waist diameter V2 in the first direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the first direction when the light beam is incident on the first light deflection device, and the focal length F2 of the collimating lens for collimating the light beam along the first direction: θ2= V1 / F2, θ2 V2=θ1 V1; The following relationship is satisfied between the light emitting length H1 of the light source in the second direction, the divergence angle θ1 of the light emitted in the second direction, the beam waist diameter H2 in the second direction when the light beam is incident on the first light deflection device, the divergence angle θ2 in the second direction when the light beam is incident on the first light deflection device, and the focal length F1 of the collimating lens for collimating the light beam along the second direction: θ2= H1 / F1, θ2 H2=θ1 H1.

8. The method according to claim 1, characterized in that Also includes: Amplifying the deflection angle of the deflected light beam along the corresponding deflection direction by a preset multiple, and amplifying the divergence angle of the light beam by a corresponding preset multiple to form a strip light beam; The divergence angle of the strip light beam along the second direction is greater than or equal to an angular interval between two adjacent second deflection angles along the second direction.

9. The method according to claim 8, characterized in that The deflection angle of the deflected light beam along the corresponding deflection direction is magnified by a preset multiple, including: at least one expansion lens magnifies the deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in at least one of the first direction and the second direction perpendicular to each other by a preset multiple.

10. The method according to claim 1, characterized in that The deflection angle range of the light beam deflected along the first direction at a plurality of first deflection angles is greater than or equal to the angle interval between two adjacent second deflection angles of the light beam along the first direction; The deflection accuracy of the light beam deflecting the first deflection angle is higher than the deflection accuracy of the light beam deflecting the second deflection angle.

11. The method according to claim 1, characterized in that In a deflection period, the plurality of different first deflection angles of the light beam change from large to small, or from small to large, or change according to a preset random rule in the first direction; The plurality of second deflection angles for deflecting the light beam within one deflection period are all the same, or all different, or some are the same and some are different.

12. The method according to claim 1, characterized in that The second light deflection device deflects the light beam after the first-order light is deflected by a plurality of second deflection angles along the first direction and the second direction, including: The control device controls the multiple deflection sub-areas in the second light deflection device to receive the deflected light beams corresponding to the light beams with multiple different first deflection angles; each deflection sub-area can adjust the deflection angle of the light beam individually; Controlling the deflection partition currently being scanned to deflect the light beam to a second deflection angle required; and At least one deflection partition that is not currently scanned is controlled to adjust the deflection angle of the light beam to a second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the light beam and before the next deflection cycle is scanned by the light beam.

13. The method according to claim 12, characterized in that The first light deflection device deflects the light beam along the first direction to a plurality of first deflection angles in one deflection cycle, comprising: the first light deflection device deflects the light beam to a plurality of different first deflection angles in a preset order in a time-sharing manner in one deflection cycle; Controlling a plurality of deflection sub-areas in the second light deflection device to receive a plurality of incident light beams at different first deflection angles, comprising: controlling the plurality of deflection sub-areas to receive the light beams at different first deflection angles in a synchronous manner; The deflection period is the time required for the first light deflecting device to deflect the incident light beam by all of a plurality of different first deflection angles, or the deflection period is the time required for the first light deflecting device to deflect the incident light beam by a specified portion of the first deflection angles.

14. The method according to claim 13, characterized in that A deflection partition can sequentially receive one, two or more incident light beams with different first deflection angles within a deflection period; The plurality of deflection partitions are configured such that the plurality of second deflection angles for light beam deflection in one deflection cycle are all the same, or are all different, or are partially the same and partially different; The number of light beams that can be received by each deflection partition is the same, different, or partially the same and partially different; accordingly, the widths of the multiple deflection partitions are the same, different, or partially the same and partially different.

15. The method according to claim 13, characterized in that The controlling of at least one deflection partition that is not currently scanned to adjust the deflection angle of the light beam to a second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the light beam and before the next deflection cycle is scanned by the light beam comprises: After determining that a deflection partition completes the beam deflection of the current deflection cycle and is in a non-scanning state, the deflection partition is controlled to adjust its deflection angle for the beam, and before entering the scanning state in the next deflection cycle, its deflection angle for the beam is adjusted to a second deflection angle required for the next deflection cycle.

16. The method according to claim 15, characterized in that If a deflection partition is a deflection partition currently scanned by the light beam, the deflection partition is determined to be in a scanning state, otherwise, the deflection partition is determined to be in a non-scanning state; or If a deflection partition is a deflection partition that is currently scanned by the light beam or is to be scanned next, it is determined that the deflection partition is in a scanning state; otherwise, it is determined that the deflection partition is in a non-scanning state.

17. The method according to claim 15, characterized in that The deflection partition currently scanned by the light beam and the next deflection partition to be scanned are determined as deflection partitions in a scanning state, and the remaining deflection partitions are determined as deflection partitions in a non-scanning state; the deflection partition currently scanned by the light beam and the next deflection partition to be scanned are adjacent deflection partitions in position.

18. The method according to claim 13, characterized in that The second optical deflection device includes at least one optical deflection unit, and the optical deflection unit includes a plurality of deflection sub-partitions. When the deflection sub-partitions include deflection sub-partitions corresponding to positions in the at least one optical deflection unit, the voltages on the electrodes at both ends of each deflection sub-partition are controlled respectively, and the deflection angle of the light beam by at least one deflection sub-partition is changed by changing the voltages on the electrodes at both ends of at least one deflection sub-partition, so as to achieve the second deflection angle of the light beam by the corresponding deflection sub-partition.

19. The method of claim 13, wherein: The number D of deflection partitions is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second optical deflection device, F is the frame rate at which the second optical deflector deflects a round of M deflection angles, and T is the time required for the second optical deflection device to complete a deflection angle adjustment.

20. The method of claim 11, wherein: The field of view of the light scanning is divided into a plurality of scanning partitions, each of which is rectangular and the incident light beam is a strip-shaped light beam; Scanning the field of view includes: deflecting a plurality of light beams with different first deflection angles to the same second deflection angle, so as to complete scanning of a corresponding scanning subarea of ​​the field of view; deflecting each light beam with a first deflection angle in the plurality of light beams with different first deflection angles to a plurality of different second deflection angles, so as to complete scanning of a plurality of scanning subareas corresponding to the plurality of different second deflection angles; The length of the light beam after being deflected by the second deflection angle is equal to the length of one direction of the scanning partition.

21. The method according to any one of claims 13 to 20, characterized in that: Also includes: The temperature of the second light deflecting device is changed to adjust the time for the second light deflecting device to adjust the deflection angle.

22. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores program data and can be executed by a processor to implement the laser radar scanning method as described in any one of claims 1-21.

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