Transmitting module, laser radar system and electronic equipment

Abstract

The utility model discloses a transmitting module, a laser radar system and electronic equipment. The emission module comprises a light source, a first light deflection device and a second light deflection device. The length of the light beam in the first direction is smaller than that in the second direction; the first light deflection device is configured to deflect the light beam along a first direction by a plurality of first deflection angles; the second light deflection device is configured to deflect 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. Therefore, the second light deflection device only needs to deflect by a small angle to cover the whole scanning area, the size and the cost of the first light deflection device and the second light deflection device can be reduced, the switching time of the deflection angle can be shortened by a small number of deflection times, and the detection frame rate can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of depth sensing, and in particular to a transmitting module, a laser radar system and an electronic device. Background Art

[0002] In recent years, depth sensing systems, such as LiDAR (LiDAR), have begun to be commercialized on a large scale in fields such as optoelectronic sensing, intelligent manufacturing, 3D navigation, and imaging. Among these, the one with the highest commercial value and the greatest development potential is its use as a light detection device for intelligent driving, providing real-time road information. This requires LiDAR to be able to detect various road signs and obstacles smaller than one meter in size, with a range of approximately 300 meters and a wide field of view. It must also maintain a signal update rate of ten to dozens of frames per second to meet high-speed vehicle driving scenarios. While maintaining range performance, the product must be relatively compact. To meet these performance requirements, current mainstream commercial vehicle-mounted lasers use mechanical or semi-solid-state scanning, illuminating targets within the scanned field of view in a time-sharing manner. However, the presence of moving parts limits system reliability and maintainability.

[0003] Compared with traditional mechanical and semi-solid-state laser radars, all-solid-state laser radars have significant advantages in system cost and reliability. The current mainstream direct time-of-flight (DTOF) Flash-type all-solid-state blind spot laser radar, such as the laser radar disclosed in the Chinese patent application with application number CN202321460026.5, uses wide-area light emission to cover the entire field of view. At the receiving end, a planar array SPAD array is used to perform time-sharing and partitioning reception of the reflected echo signal, ultimately achieving three-dimensional imaging of targets within tens of meters. Without changing the frame rate, detection angle, and angular resolution, in order to meet the needs of vehicle navigation, the detection power needs to be increased to enable the detection distance to reach hundreds of meters. This is currently limited by the system's heat dissipation capacity and cost control requirements, and is difficult to achieve in engineering.

[0004] In order to improve the detection range of all-solid-state lidar, during the all-solid-state optical scanning process, it is considered to use an optical deflection structure to amplify the light deflection angle. For example, an acousto-optic deflector (AOD) combined with a liquid crystal polarization grating (LCPG) can be used for secondary deflection to achieve continuous and fine adjustment of the one-dimensional light beam deflection angle within a larger angle range. Utility Model Content

[0005] The inventors of this application have discovered that although some lidar systems have considered using AOD combined with LCPG for secondary deflection, they generally use point light sources. When the light beam generated by them reaches the distant scanning field of view area after secondary deflection, the scanning light beam formed is generally a circular or nearly circular beam. Usually, the AOD and LCPG need to be deflected at many angles in both the horizontal and vertical directions to cover the entire field of view area. The more deflection angles to be achieved, the larger the size of the AOD and the more layers of LCPG, resulting in large size and high cost of the AOD and LCPG. Moreover, the more deflections, the longer the beam deflection time required to cover the entire field of view area, which is not conducive to meeting the high frame rate required for automotive scenarios.

[0006] In view of the above problems, the present invention is proposed to provide a transmitting module, a laser radar system, an electronic device and a laser radar scanning method that overcome the above problems or at least partially solve the above problems.

[0007] The embodiment of the present utility model provides a transmitting module, comprising: a light source, a first light deflection device and a second light deflection device;

[0008] a light source 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;

[0009] a first light deflecting device configured to deflect the light beam along a first direction by a plurality of first deflection angles;

[0010] a second light deflecting device configured to deflect the light beam deflected by the first light deflecting device by a plurality of second deflection angles in a first direction and a second direction to project a scanning light beam; wherein the length of the scanning light beam in the first direction is smaller than the length in the second direction;

[0011] The length of the scanning light beam in the second direction is not less than the length of the light beam emitted by the light source in the second direction.

[0012] In some optional embodiments, the light source includes a plurality of light-emitting units that are spliced together to emit a light beam with a required aspect ratio.

[0013] In some optional embodiments, the light emitting unit is at least one of an edge emitting laser EEL, a vertical cavity surface emitting laser VCSEL, a light emitting diode LED, a laser diode LD, a semiconductor laser, and a fiber laser.

[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 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.

[0015] In some optional embodiments, the aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 75:1; or

[0016] The aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; and the aspect ratio of the scanning light beam is 25:1.

[0017] In some optional embodiments, the above-mentioned emission module also includes a collimating device, which is configured to collimate the light beam before the light beam enters the first light deflection device; wherein, the collimation of the collimated light beam along the first direction is higher than the collimation along the second direction; the first direction is perpendicular to the second direction.

[0018] In some optional embodiments, the collimating device includes at least one collimating lens, and the light source is arranged on the focal plane of the collimating lens; when the collimating device includes at least two collimating lenses, the focal planes of at least two collimating lenses coincide.

[0019] In some optional embodiments, the collimating device includes a first cylindrical lens and a second cylindrical lens, 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; or,

[0020] The collimating device includes a spherical lens configured to collimate the light beam along a first direction and a second direction; or,

[0021] The collimating device 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 simultaneously.

[0022] In some optional embodiments, the collimating device is configured to collimate a light beam with an aspect ratio A into a light beam with an aspect ratio B, and A>B;

[0023] The first light deflection device and the second light deflection device are configured to deflect the light beam with an aspect ratio of B and project a light beam with an aspect ratio of C, where C>B.

[0024] In some optional embodiments, the following relationships are 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 that collimates the light beam along the first direction: θ2=V1 / F2, θ2V2=θ1V1.

[0025] In some optional embodiments, the following relationships are satisfied among the luminous length H1 of the light source in the second direction, the divergence angle Θ1 of the light source 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, Θ2H2=Θ1H1.

[0026] In some optional embodiments, 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.

[0027] In some optional embodiments, the first direction is a vertical direction, and the second direction is a horizontal direction; or the first direction is a horizontal direction, and the second direction is a vertical direction.

[0028] In some optional embodiments, the above-mentioned transmitting module also includes a deflection expansion device, 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.

[0029] In some optional embodiments, the deflection expanding device 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 by a preset multiple before the light beam is incident on the second light deflection device; or

[0030] The deflection expansion device is arranged on the light-emitting side of the second light deflection device, and is configured to amplify the deflection angle of the light beam deflected by the second light deflection device by a preset multiple.

[0031] In some optional embodiments, a divergence angle of the strip light beam formed after deflection expansion by the deflection expansion device along the second direction is greater than or equal to an angular interval between two adjacent second deflection angles of the second light deflection device along the second direction.

[0032] In some optional embodiments, the polarization expanding device includes at least one polarization expanding lens, which is a single lens or a combination of two or more lenses; the polarization expanding lens includes at least one or any combination of a cylindrical lens, a spherical lens, a super lens, and a Fresnel lens;

[0033] The at least one polarization expander lens is configured to magnify a deflection angle of the light beam deflected by the first light deflection device in at least one of the first direction and the second direction by a preset multiple.

[0034] In some optional embodiments, the focal length of the polarization expanding lens is set according to the magnification of the deflection angle. When the polarization expanding device includes two polarization expanding lenses, the focus of one side of one polarization expanding lens coincides with the focus of one side of the other polarization expanding lens, and the magnification is the ratio of the focal lengths of the two polarization expanding lenses.

[0035] In some optional embodiments, the distance between the first light deflecting device and the first polarization expanding lens in the polarization expanding device 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.

[0036] In some optional embodiments, the polarization expanding device includes at least one of a first cylindrical lens group and a second cylindrical lens group; the first cylindrical lens group includes a first polarization expanding cylindrical lens and a second polarization expanding cylindrical lens, and is 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 a third polarization expanding cylindrical lens and a fourth polarization expanding cylindrical lens, and is 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;

[0037] or

[0038] The polarization expanding device includes a first polarization expanding spherical lens and a second polarization expanding spherical lens, which are configured to amplify 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.

[0039] In some optional embodiments, the first light deflection device is configured to deflect the light beam along the first direction in a deflection angle range that is greater than or equal to an angular interval between two adjacent second deflection angles of the second light deflection device along the first direction.

[0040] In some optional embodiments, the first light deflection device 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.

[0041] In some optional embodiments, the first light deflection device is an acousto-optic deflector, and the second light deflection device is a liquid crystal polarization grating.

[0042] In some optional embodiments, the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating plate included in the liquid crystal polarization grating is nematic liquid crystal or blue phase liquid crystal.

[0043] In some optional embodiments, the deflection accuracy of the first light deflection device on the light beam is higher than the deflection accuracy of the second light deflection device on the light beam.

[0044] In some optional embodiments, the deflection speed of the light beam by the first light deflection device is higher than the deflection speed of the light beam by the second light deflection device.

[0045] In some optional embodiments, the first light deflecting device is configured to deflect the incident light beam to a plurality of different first deflection angles in a preset order in a time-sharing manner within a deflection period;

[0046] 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.

[0047] In some optional embodiments, within a deflection period, the deflection angles of the light beams with the multiple different first deflection angles vary from large to small, or from small to large, or vary according to a preset random rule in the first direction.

[0048] In some optional embodiments, the second light deflection device includes at least two light deflection unit groups, each light deflection unit group includes at least one of the light deflection units, wherein at least one light deflection unit group is configured to deflect the light beam in a first direction, and at least one light deflection unit group is configured to deflect the light beam in a second direction.

[0049] In some optional embodiments, the second light deflecting device includes a plurality of deflection sub-areas, and each deflection sub-area can independently adjust the deflection angle of the incident light beam;

[0050] The plurality of deflection subareas are configured to deflect the light beam to a second deflection angle required by the deflection subarea currently being scanned;

[0051] The above-mentioned transmitting module also includes a control device for controlling the currently scanned deflection partition in the second optical deflection device to deflect the light beam, and controlling at least one deflection partition 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 to the light beam is adjusted to the second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the incident light beam and before the next deflection cycle is scanned by the light beam.

[0052] In some optional embodiments, the control device is used to control the first optical deflection device to deflect the light beam to multiple different first deflection angles in a time-sharing manner within a deflection cycle, to correspond to multiple deflection partitions incident on the second optical deflection device, and the multiple deflection partitions receive the incident light beam in a time-sharing manner and deflect the light beam.

[0053] In some optional embodiments, the first optical deflection device is configured to, within a deflection period, sequentially direct a plurality of light beams with different first deflection angles into corresponding deflection partitions in the second optical deflection device in a preset order; and a deflection partition is configured to deflect the light beam to a corresponding second deflection angle within a deflection period.

[0054] In some optional embodiments, the plurality of deflection partitions are configured to deflect the light beam at a plurality of second deflection angles that are the same, or different, or partially the same and partially different within one deflection period.

[0055] In some optional embodiments, a deflection partition may be configured to sequentially receive one, two, or more expanded light beams corresponding to light beams with different first deflection angles within a deflection period.

[0056] In some optional embodiments, the arrangement direction of the multiple deflection zones is consistent with the scanning direction of the multiple light beams with different first deflection angles.

[0057] In some optional embodiments, the plurality of deflection partitions included in the second light deflection device are arranged along a first direction.

[0058] In some optional embodiments, the multiple deflection partitions are configured as follows: the number of light beams 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.

[0059] In some optional embodiments, the 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 beams of multiple different first deflection angles, and the width of each deflection partition is determined according to the number of received beams and the width of the beams.

[0060] In some optional embodiments, the control device is specifically configured to:

[0061] After determining that a deflection partition has completed the light deflection of the current deflection cycle and is in a non-scanning state, the deflection partition is controlled to adjust its deflection angle of the light beam, and before entering the scanning state in the next deflection cycle, its deflection angle of the light beam is adjusted to the second deflection angle required for the next deflection cycle.

[0062] In some optional embodiments, the control device is specifically configured to:

[0063] According to the scanning position of the light beam on the second optical deflection device, the deflection partition currently in the scanning state and the deflection partition in the non-scanning state are determined; for the deflection partition in the non-scanning state, if the scanning order of the deflection partition is before the deflection partition in the scanning state, it is considered that the deflection partition has completed the light beam deflection of the current deflection cycle.

[0064] In some optional embodiments, 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

[0065] 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.

[0066] 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.

[0067] In some optional embodiments, when the second light deflection device has a non-partitioned structure, the control device is used to control a voltage applied to an electrode of the second light deflection device to adjust a refractive index of a medium in the second light deflection device with respect to an incident light beam, thereby adjusting a deflection angle of the incident light beam by the second light deflection device;

[0068] When the second light deflection device has a partitioned structure, the control device is used to control the voltage applied to the electrodes of each deflection partition 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.

[0069] In some optional embodiments, when the second light deflection device adopts a liquid crystal polarization grating and has a non-partitioned structure, the control device 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, thereby changing the second deflection angle of the light beam by the second light deflection device;

[0070] When the second light deflection device adopts a liquid crystal polarization grating and has a partitioned structure, the control device is used to control the voltage applied to the electrodes of each deflection partition to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating to change the second deflection angle of the deflection partition to the light beam.

[0071] In some optional embodiments, when the second optical deflection device includes at least two optical deflection units, the optical deflection unit includes multiple deflection sub-partitions; the deflection sub-partitions include deflection sub-partitions corresponding to positions in the at least one optical deflection unit; the deflection sub-partitions in at least one optical deflection unit included in a deflection sub-partition can form a deflection optical path.

[0072] In some optional embodiments, when the second optical deflection device includes two optical deflection units, the deflection partition includes two deflection sub-partitions corresponding to the positions on the two optical deflection units; when the second optical deflection device includes multiple optical deflection units, the deflection partition includes multiple deflection sub-partitions corresponding to the positions on the multiple optical deflection units.

[0073] In some optional embodiments, the control device is specifically used to: respectively control the voltage on the two end electrodes of each deflection sub-partition, 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, so as to achieve the change of the second deflection angle of the corresponding deflection sub-partition to the light beam.

[0074] In some optional embodiments, the light deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarization grating, and the liquid crystal half-wave plate includes electrodes arranged on two opposite sides and a half-wave plate liquid crystal layer arranged between the electrodes on both sides;

[0075] One side electrode of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the other side electrode is a first whole electrode block, and each deflection sub-region corresponds to at least one first electrode block; each deflection sub-region includes a portion on the liquid crystal half-wave plate corresponding to the position of the at least one first electrode block and a portion on the liquid crystal polarization grating corresponding to the position of the at least one first electrode block; or

[0076] The electrodes on both sides of the liquid crystal half-wave plate include a plurality of first electrode blocks, two opposing first electrode blocks form a first electrode pair, and each sub-deflection sub-area corresponds to at least one first electrode pair; each deflection sub-area includes a portion on the liquid crystal half-wave plate corresponding to the at least one first electrode pair and a portion on the liquid crystal polarization grating corresponding to the at least one first electrode pair;

[0077] The deflection angle of the light beam caused by the corresponding deflection sub-region is adjusted by changing the voltage applied to the electrodes corresponding to the deflection sub-regions in the liquid crystal half-wave plate.

[0078] In some optional embodiments, the light deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarization grating plate; the liquid crystal half-wave plate includes electrodes arranged on two opposite sides and a half-wave plate liquid crystal layer arranged between the electrodes; the liquid crystal polarization grating plate includes electrodes arranged on two opposite sides and a grating liquid crystal layer arranged between the electrodes;

[0079] One side electrode of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the other side electrode is a first whole electrode; one side electrode of the liquid crystal polarization grating plate includes a plurality of second electrode blocks, and the other side electrode is a second whole electrode; at least one second electrode block on the liquid crystal polarization grating plate and at least one first electrode block corresponding to a position on the liquid crystal half-wave plate form a block group; or

[0080] The electrodes on both sides of the liquid crystal half-wave plate include a plurality of first electrode blocks, and two opposite first electrode blocks form a first electrode pair; the electrodes on both sides of the liquid crystal polarization grating plate include a plurality of second electrode blocks, and two opposite second electrode blocks form a second electrode pair; at least one second electrode pair on the liquid crystal polarization grating plate and at least one first electrode pair at a corresponding position on the liquid crystal half-wave plate form a block group; or

[0081] One side electrode of the liquid crystal polarization grating comprises a plurality of second electrode blocks, and the other side electrode is a second whole electrode; both side electrodes of the liquid crystal half-wave plate comprise a plurality of first electrode blocks, and two opposing first electrode blocks form a first electrode pair; at least one second electrode block on the liquid crystal polarization grating and at least one first electrode pair corresponding to a position on the liquid crystal half-wave plate form a block group; or

[0082] The electrodes on both sides of the liquid crystal polarization grating plate include a plurality of second electrode blocks, and two opposing second electrode blocks form a second electrode pair. The electrode on one side of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the electrode on the other side is a first whole electrode block. At least one second electrode pair on the liquid crystal polarization grating plate and at least one first electrode block corresponding to a position on the liquid crystal half-wave plate form a block group.

[0083] Each deflection sub-partition corresponds to at least one block group; each deflection sub-partition includes a portion on the liquid crystal half-wave plate corresponding to the position of the block group, and a portion on the liquid crystal polarization grating corresponding to the position of the block group;

[0084] The deflection angle of the light beam by the corresponding deflection sub-partition is adjusted by changing the voltage applied to the electrodes corresponding to the deflection sub-partition in the liquid crystal half-wave plate and the voltage applied to the electrodes corresponding to the deflection sub-partition in the liquid crystal polarization grating.

[0085] In some optional embodiments, the liquid crystal polarization gratings of all the light deflection units in the second light deflection device are passive liquid crystal polarization gratings, or the liquid crystal polarization gratings of all the light deflection units in the second light deflection device are active liquid crystal polarization gratings, or the liquid crystal polarization gratings of some of the light deflection units in the second light deflection device are passive liquid crystal polarization gratings, and the liquid crystal polarization gratings of some of the light deflection units are active liquid crystal polarization gratings; the liquid crystal material of the liquid crystal layer is nematic liquid crystal or blue phase liquid crystal.

[0086] In some optional embodiments, the liquid crystal half-wave plate further comprises a first substrate and a second substrate disposed opposite to each other, the electrodes on both sides are respectively disposed on inner surfaces of the first substrate and the second substrate facing each other, and the inner surfaces are planes;

[0087] The liquid crystal polarization grating plate further comprises a third substrate and a fourth substrate arranged opposite to each other. The electrodes on both sides are respectively arranged on the inner surfaces of the third substrate and the fourth substrate facing each other, and the inner surfaces are planes.

[0088] In some optional embodiments, the second light deflection device further includes a quarter wave plate disposed in front of the first liquid crystal half wave plate, for changing the polarization state of the light beam.

[0089] In some optional embodiments, the time for adjusting the second deflection angle of the light beam by the deflection partition is no longer than the time interval between two adjacent deflection periods of the deflection partition being scanned by the light beam.

[0090] In some optional embodiments, the number of deflection partitions is determined based on 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 with 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.

[0091] 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.

[0092] In some optional embodiments, the light beam is deflected at multiple different deflection angles by the first light deflection device and the second light deflection device in a time-sharing manner to scan a preset field of view range, wherein the length of the preset field of view range in the first direction is smaller than the length in the second direction.

[0093] In some optional embodiments, the second light deflection device is configured to deflect light beams incident at different positions by the same second deflection angle, thereby completing scanning of a corresponding scanning subarea within the field of view; and deflect light beams incident at each of the different positions by multiple different second deflection angles, thereby completing scanning of multiple scanning subareas corresponding to the different multiple second deflection angles;

[0094] The scanning subarea is rectangular, and the length of the strip light beam after being deflected by the second deflection angle is equal to the length of the scanning subarea in one direction.

[0095] In some optional embodiments, the second light deflection device is configured to: deflect a plurality of light beams with different first deflection angles to the same second deflection angle within one deflection period to complete scanning of a corresponding scanning subarea within the field of view; different deflection periods deflect the light beams with different first deflection angles at different second deflection angles; or

[0096] Within a deflection cycle, a plurality of light beams at different first deflection angles are respectively deflected to one of a plurality of different second deflection angles to scan a portion of the corresponding scanning subarea; wherein within a deflection cycle, the second deflection angles at which the light beams at the plurality of different first deflection angles are deflected are the same or different; and within different deflection cycles, the second deflection angles at which the light beams at the first deflection angles are deflected are different;

[0097] The scanning subarea is rectangular, and the length of the light beam after being deflected by the second deflection angle is equal to the length of the scanning subarea in one direction.

[0098] In some optional embodiments, the transmitting module further includes: a control device;

[0099] The control device is used to control the first light deflection device and the second light deflection device to deflect the light beam.

[0100] In some optional embodiments, when the second optical deflection device includes multiple deflection partitions, the control device is specifically used to execute the following control processes in parallel: controlling the deflection partition currently being scanned in the second optical deflection device to deflect the light beam, and controlling at least one deflection partition that is not currently being scanned to adjust its deflection angle to the light beam.

[0101] In some optional embodiments, when the second light deflecting device includes a plurality of deflection partitions, the control device includes a first control unit and a second control unit;

[0102] The first control unit is used to control the first light deflection device to deflect a plurality of different first deflection angles in a time-sharing manner within a deflection period, and to direct the light beam of each first deflection angle to be incident on a corresponding deflection partition of the second light deflection device;

[0103] The second control unit is used to control the multiple deflection partitions to receive the light beam in a timely manner and deflect the light beam to the second deflection angle required, and to control the deflection partitions to pre-adjust their deflection angles to the light beam before being scanned by the light beam; wherein, the deflection angle of at least one deflection partition to the light beam is adjusted to the second deflection angle required for the next deflection cycle after the light beam scanning ends in the current deflection cycle and before the light beam scanning starts in the next deflection cycle.

[0104] In some optional embodiments, when the first optical deflection device is an acousto-optic deflector, the control device is used to apply a driving signal to the acoustic wave generator of the first optical deflection device, and control the acoustic wave frequency of the acoustic wave generator acting on the acousto-optic crystal of the first optical deflection device through the driving signal, so as to change the deflection angle of the light beam by the first optical deflection device.

[0105] In some optional embodiments, the transmitting module further includes:

[0106] The temperature regulator 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.

[0107] In some optional embodiments, when the light beam emitted by the light source is linearly polarized light, the emission module further includes a 1 / 2 wave plate disposed between the collimating device and the first light deflection device for changing the polarization direction of the light beam.

[0108] The optical axis of the 1 / 2 wave plate is perpendicular to the direction of the outgoing light beam of the collimator, and the electric field direction of the linearly polarized light forms a 45-degree angle with the fast axis of the 1 / 2 wave plate, or the electric field direction of the linearly polarized light forms a 45-degree angle with the slow axis of the 1 / 2 wave plate.

[0109] In some optional embodiments, the transmitting module is used in a laser radar system; or the transmitting module is a transmitting module in a laser radar system.

[0110] An embodiment of the present invention provides a laser radar system, including a receiving module and the above-mentioned transmitting module, wherein the receiving module is configured to sense light signals from a field of view range and obtain three-dimensional information of the field of view range by processing and analyzing the light signals.

[0111] An embodiment of the present invention provides an electronic device, comprising the above-mentioned laser radar system.

[0112] The present invention provides a laser radar scanning method, comprising the following steps:

[0113] 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 along the first direction is less than the length along the second direction;

[0114] The second light deflection device deflects the light beam after the first-level light deflection along the first direction and the second direction by multiple 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 its length in the second direction.

[0115] In some optional 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.

[0116] In some optional embodiments, the aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 75:1; or

[0117] The aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; and the aspect ratio of the scanning light beam is 25:1.

[0118] In some optional embodiments, the above method further includes:

[0119] 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; the first direction is perpendicular to the second direction.

[0120] In some optional embodiments, collimating the light beam includes:

[0121] 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

[0122] A spherical lens collimates the incident light beam in a first direction and a second direction simultaneously; or

[0123] 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 simultaneously.

[0124] In some optional embodiments, collimating the light beam includes:

[0125] collimating a 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 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;

[0126] After being collimated, the light beam with an aspect ratio of B is diverged into a light beam with an aspect ratio of C after being deflected at the first deflection angle and the second deflection angle, and C>B.

[0127] In some optional embodiments, the following relationships are 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 that collimates the light beam along the first direction: θ2=V1 / F2, θ2V2=θ1V1.

[0128] In some optional embodiments, the following relationships are satisfied among the luminous length H1 of the light source in the second direction, the divergence angle Θ1 of the light 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, Θ2H2=Θ1H1.

[0129] In some optional embodiments, 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.

[0130] In some optional 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.

[0131] In some optional 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.

[0132] In some optional embodiments, the deflection angle of the deflected light beam in the corresponding deflection direction is magnified by a preset multiple, including: the polarization expansion device magnifies the deflection angle of the light beam deflected by the first optical deflection device or the second optical deflection device in the corresponding deflection direction by a preset multiple.

[0133] In some optional embodiments, the deflection expanding 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, including:

[0134] At least one polarization expander 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 a first direction and a second direction perpendicular to each other by a preset multiple.

[0135] In some optional embodiments, at least one polarization expander lens amplifies a deflection angle of the light beam deflected by the first light deflection device or the second light deflection device in at least one of a first direction and a second direction perpendicular to each other by a predetermined multiple, including:

[0136] The first cylindrical 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 cylindrical lens group including a first polarization expanding cylindrical lens and a second polarization expanding cylindrical lens, 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;

[0137] The second cylindrical lens group amplifies 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 cylindrical lens group including a third polarization expanding cylindrical lens and a fourth polarization expanding cylindrical lens, 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;

[0138] or

[0139] The first expanding spherical lens and the second expanding spherical lens magnify 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 expanding spherical lens to the focal length of the second expanding spherical lens.

[0140] In some optional embodiments, amplifying the divergence angle of the light beam by a corresponding preset multiple includes:

[0141] 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 is magnified by a preset multiple, and the divergence angle magnification is the same as the deflection angle magnification of the light beam in the deflection direction.

[0142] In some optional embodiments, the deflection angle range of the light beam at the multiple first deflection angles deflected along the first direction is greater than or equal to the angular interval between two adjacent second deflection angles of the light beam along the first direction.

[0143] In some optional 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.

[0144] 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.

[0145] In some optional embodiments, within a deflection period, the deflection angles of the light beams with the multiple different first deflection angles vary from large to small, or from small to large, or vary according to a preset random rule in the first direction.

[0146] 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:

[0147] The control device controls the plurality of deflection sub-areas in the second light deflection device to receive deflected light beams corresponding to the light beams with the plurality of different first deflection angles; each deflection sub-area can adjust the deflection angle of the light beam individually;

[0148] controlling the deflection partition currently being scanned to deflect the light beam to a second deflection angle required; and

[0149] 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 light beam scan ends in the current deflection cycle and before the light beam scan starts in the next deflection cycle.

[0150] In some optional embodiments, the first light deflecting device deflects the light beam along the first direction by a plurality of first deflection angles within a deflection period, comprising: the first light deflecting device deflects the light beam by a plurality of different first deflection angles in a time-sharing manner according to a preset order within a deflection period;

[0151] 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 includes: controlling the plurality of deflection sub-areas to receive the light beams at different first deflection angles at the same time;

[0152] 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.

[0153] In some optional embodiments, 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.

[0154] 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.

[0155] In some optional embodiments, the plurality of deflection partitions are configured to deflect the light beam at a plurality of second deflection angles that are all the same, or are all different, or are partially the same and partially different within one deflection period.

[0156] In some optional 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.

[0157] In some optional embodiments, controlling at least one deflection subarea that is not currently scanned to adjust the deflection angle of the light beam to a second deflection angle required for the next deflection period after the light beam scan ends in the current deflection period and before the light beam scan starts in the next deflection period includes:

[0158] After determining that a deflection partition has completed 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 of the light beam, and before entering the scanning state in the next deflection cycle, its deflection angle of the light beam is adjusted to the second deflection angle required for the next deflection cycle.

[0159] In some optional embodiments, 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

[0160] If a deflection partition is the deflection partition that the light beam is currently scanning 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.

[0161] 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.

[0162] In some optional 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.

[0163] In some optional embodiments, when 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 to change the second deflection angle of the deflection partition to the light beam.

[0164] In some optional embodiments, the second optical deflection device includes at least one optical deflection unit, and the optical deflection unit includes multiple 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 of 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 of the corresponding deflection sub-partition.

[0165] In some optional embodiments, when the second light deflection device includes at least two light deflection unit groups, each light deflection unit group including at least one light deflection unit; controlling the currently scanned deflection subarea to deflect the light beam to the second deflection angle required includes:

[0166] The light beam is deflected in a first direction by a second deflection angle required by a deflection sub-partition of a light deflection unit currently being scanned in at least one light deflection unit group, and / or the light beam is deflected in a second direction by a second deflection sub-partition of a light deflection unit currently being scanned in at least one light deflection unit group, wherein the first direction and the second direction are perpendicular.

[0167] In some optional embodiments, the time for adjusting the second deflection angle of the light beam by the deflection partition is no longer than the time interval between two adjacent scans of the deflection partition by the light beam.

[0168] In some optional embodiments, the number of deflection partitions is determined based on 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 with 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.

[0169] 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.

[0170] In some optional embodiments, the following control processes are performed in parallel: controlling the 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.

[0171] 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-shaped light beam;

[0172] Scanning the field of view includes: deflecting a plurality of light beams having different first deflection angles to a same second deflection angle, thereby completing scanning of a corresponding scanning subarea of the field of view; deflecting each light beam having a first deflection angle in the plurality of light beams having different first deflection angles to a plurality of different second deflection angles, thereby completing scanning of a plurality of scanning subareas corresponding to the plurality of different second deflection angles;

[0173] 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.

[0174] In some optional embodiments, within one 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 within the field of view; each deflection cycle corresponds to a different second deflection angle; different deflection cycles deflect the light beams with different first deflection angles at different second deflection angles; or

[0175] Within one deflection cycle, multiple light beams with different first deflection angles are respectively deflected to one of multiple different second deflection angles to scan partial areas in the corresponding scanning partitions; wherein, within one deflection cycle, multiple light beams with different first deflection angles are deflected to the same or different second deflection angles; and within different deflection cycles, each light beam with a first deflection angle is deflected to a different second deflection angle.

[0176] In some optional embodiments, the above 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.

[0177] The beneficial effects of the above technical solution provided by the embodiment of the present utility model include at least:

[0178] The transmitting module provided by the present invention has a deflected light beam having a length in a first direction that is shorter than a length in a second direction. During the two-stage optical deflection process, the light beam naturally diverges to form a stripe-shaped light beam whose length is along the second direction. The stripe-shaped light beam is deflected one-dimensionally in the first direction (i.e., the width of the light beam) by a first optical deflection device, so that a second deflection angle corresponding to a second optical deflection device can scan a substantially rectangular scanning area. The second optical deflection device deflects the light beam two-dimensionally at multiple second deflection angles in the first and second directions, respectively, to scan multiple scanning areas. Because the stripe-shaped light beam can already cover a wide angular field of view in its length, deflection in its width by the first optical deflection device allows it to cover a wider angular field of view. Furthermore, the second optical deflection device only needs to deflect the light beam by a smaller angle in both directions to cover the entire scanning area. This reduces the size and cost of the first and second optical deflection devices. Furthermore, the reduced number of deflections shortens the switching time between deflection angles, facilitating an improved 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, which can achieve better detection effect; it can simultaneously meet the long-distance and large field-of-view detection needs in application scenarios such as autonomous driving and in-vehicle navigation.

[0179] Furthermore, before the light beam enters the first optical deflection device, the light beam is collimated to meet the requirement of sufficient deflection. Regarding 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 requirements of the first optical deflection device, such as the requirement that the aspect ratio should not be too large when cutting AOD crystals, 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 requirements for alignment in the deflection direction. After the light beam is deflected by the first and second optical deflection devices, the light beam has a high collimation and a small divergence angle in the width direction, and a low collimation and a large divergence angle in the length direction, thereby increasing the aspect ratio of the light beam reaching a distance, and forming a long scanning light beam with an aspect ratio that meets the requirements. 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, which can obtain better detection effect; it can simultaneously meet the long-distance and large field-of-view detection needs in application scenarios such as autonomous driving and in-vehicle navigation.

[0180] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The objectives and other advantages of the present invention can be achieved and obtained by the structures particularly pointed out in the written description, claims, and drawings.

[0181] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0182] 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:

[0183] Figure 1 This is a schematic structural diagram of the transmitting module in the first embodiment of the present utility model;

[0184] Figure 2 This is one of the three-dimensional structural diagrams of the emission module in the first embodiment of the present utility model;

[0185] Figure 3 This is the second schematic diagram of the three-dimensional structure of the transmitting module in the first embodiment of the present utility model;

[0186] Figure 4 This is a schematic structural diagram of the light source in the first embodiment of the present utility model;

[0187] Figure 5 This is a schematic diagram of a specific structure of the transmitting module in the first embodiment of the present utility model;

[0188] Figure 6 This is a schematic diagram of the light path in the vertical direction in the first embodiment of the present utility model;

[0189] Figure 7 This is a schematic diagram of the light path in the horizontal direction in the first embodiment of the present utility model;

[0190] Figure 8a Schematic diagram of the optical path when the polarization expansion device includes two positive lenses in Example 1 of the present utility model;

[0191] Figure 8b Schematic diagram of the optical path when the polarization expansion device includes a positive lens and a negative lens in Example 1 of the present utility model;

[0192] Figure 9 This is a schematic diagram of the structure of the transmitting module in the second embodiment of the present invention;

[0193] Figure 10a This is a schematic structural diagram of a second light deflection device with divided electrodes on one side of a liquid crystal half-wave plate in a second embodiment of the present invention;

[0194] Figure 10b This is a schematic structural diagram of a second light deflection device with electrodes divided into blocks on both sides of a liquid crystal half-wave plate in a second embodiment of the present invention;

[0195] Figure 10c This is a schematic structural diagram of a second light deflection device with a liquid crystal half-wave plate and a liquid crystal polarization grating plate with one side electrode block in the second embodiment of the present invention;

[0196] Figure 10d This is a schematic structural diagram of a second light deflection device with electrodes on both sides of a liquid crystal half-wave plate and a liquid crystal polarization grating in a second embodiment of the present invention;

[0197] Figure 11a This is a schematic structural diagram of a second light deflection device using a passive liquid crystal grating in the second embodiment of the present invention;

[0198] Figure 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 utility model;

[0199] Figure 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 utility model;

[0200] Figure 12 This is one of the example diagrams of the scanning path of the light deflection unit in the second embodiment of the present utility model;

[0201] Figure 13 This is the second example diagram of the scanning path of the light deflection unit in the second embodiment of the present invention;

[0202] Figure 14 This is the third example diagram of the scanning path of the light deflection unit in the second embodiment of the present invention;

[0203] Figure 15 This is a schematic diagram of the structure of the transmitting module in the third embodiment of the present invention;

[0204] Figure 16 This is a schematic diagram of the structure of the transmitting module in the fourth embodiment of the present utility model;

[0205] Figure 17 Schematic diagram of the structure of the transmitting module in the fifth embodiment of the present invention;

[0206] Figure 18 This is a schematic structural diagram of a laser radar system in an embodiment of the present utility model;

[0207] Figure 19 This is a flow chart of the laser radar scanning method in an embodiment of the present utility model.

[0208] Description of reference numerals:

[0209] 1. Transmitter module; 2. Receiver module;

[0210] 100, first light deflection device; 200, second light deflection device; 300, light source; 400, collimation device; 500, deflection expansion device; 600, control device;

[0211] 110, first control unit; 128, lens group; 1281, first polarization expanding lens; 1282, second polarization expanding lens;

[0212] 210, light deflection unit; 220, light deflection unit group; 230, second control unit; 240, temperature regulator;

[0213] 211, first electrode block; 2110, first electrode pair; 212, deflection sub-zone; 2121, deflection sub-zone; 213, first integral electrode; 214, liquid crystal half-wave plate; 215, half-wave plate liquid crystal layer; 216, liquid crystal polarization grating; 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 integral electrode;

[0214] 310. Light-emitting unit. DETAILED DESCRIPTION

[0215] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although 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. Rather, 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.

[0216] At present, AOD is combined 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 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 to form 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.

[0217] In order to meet the detection needs of long distance and large field of view and obtain better detection effects, the inventors of this application have fully studied the deflection requirements of AOD and LCPG, as well as the deflection and propagation characteristics of the light beam, and found that splicing the edge emitting laser (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 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. Therefore, the size and cost of AOD and LCPG can be reduced while meeting the requirements of scanning a larger field of view at a higher frame rate.

[0218] In addition, considering that the AOD deflects the light beam, the collimation of the light beam in the deflection direction is required to be sufficiently large. 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. This can meet the AOD's requirement to deflect the light beam in the width direction. At the same time, the aspect ratio of the light beam can be relatively reduced when it reaches the AOD, taking into account the characteristic that the aspect ratio is not 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, it can form a strip scanning beam after reaching a distance, thereby taking into account the deflection requirements of the AOD and the crystal size, 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.

[0219] Example 1

[0220] The first embodiment 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 and a second light deflection device 200;

[0221] A light source 300 is configured to emit a light beam, wherein the length of the light beam along the first direction is shorter than the length along the second direction;

[0222] 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;

[0223] 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.

[0224] The structure of the transmitting module provided in the first embodiment of the present invention is as follows: Figure 1 、 Figure 2 and Figure 3 As shown, another optional structure of the emission module includes a control device 600, a light source 300, a first light deflection device 100 and a second light deflection device 200;

[0225] A light source 300 is configured to emit a light beam, wherein the length of the light beam along the first direction is shorter than the length along the second direction;

[0226] 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;

[0227] The second light deflection device 200 is configured to deflect 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 project a scanning light beam; the length of the scanning light beam in the first direction is smaller than the length in the second direction;

[0228] The control device 600 is used to control the first light deflection device 100 and the second light deflection device 200 to deflect the light beam.

[0229] The transmitting module provided in the first embodiment of the present invention is Figure 5 As shown, an optional specific structure of the emission module may be based on the above optional 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.

[0230] Optionally, in the transmitting 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. Alternatively, the length of the scanning light beam emitted by the second light deflection device in the second direction may be less than the length of the light beam emitted by the light source in the second direction.

[0231] The transmitting module provided in the first embodiment of the present invention is Figure 5As shown, an optional specific structure of the transmitting module, based on the above optional structure, further includes: a deflection expanding 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 by which the deflection expanding device 500 amplifies the deflection angle of the light beam can be set as needed. Optionally, 1 <U<10。

[0232] The various optional structures of the above-mentioned transmitting module and the components involved therein are described in detail below with reference to the accompanying drawings.

[0233] In some embodiments, a light source control unit (not shown) can be used to control the light source 300 to emit light according to a preset time sequence. The shape of the generated light beam can be determined as needed. For example, the length along the first direction can be less than the length along the second direction. Thus, 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 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 vertical and the second direction can be horizontal.

[0234] The aforementioned transmitting module utilizes a strip-shaped beam whose length along the first direction is shorter than its length along the second direction. This, combined with the one-dimensional deflection of the first optical deflector 100 and the two-dimensional deflection of the second optical deflector 200, creates a long strip shape at the remote scanning position. The two-dimensional deflection of the second optical deflector 200 shortens the size of the strip-shaped beam, enabling segmented scanning of the field of view. This is because, after the field of view is divided into multiple scanning segments, the strip-shaped beam only needs to cover one scanning segment, and its length only needs to be the length of that segment in one direction. Compared to existing scanning methods, this allows for a significantly smaller beam size, significantly reducing the crosstalk caused by highly reflective objects. Furthermore, the length of the strip-shaped beam (the second direction) is aligned with the length of the field of view, reducing the number of deflections of the second optical deflector 200 in the second direction. This, in turn, reduces the number of optical deflection units required for the second optical deflector 200, enabling a thinner and smaller device. In addition, the size of the light beam used for scanning is reduced, and there is no need to specifically expand the light beam 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.

[0235] 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 optical deflection device 100 can also be within a certain range to adapt to the light aperture size of the first optical deflection device. After being deflected by the first optical deflection device 100 and the second optical deflection device 200, a scanning light beam with a certain aspect ratio is formed.

[0236] In some embodiments, the light beam emitted by the light source 300 is a strip-shaped beam with an aspect ratio of 20:1 to 100:1; the light beam incident on the first optical deflection device 100 has an aspect ratio of 3:1 to 1:2; and the scanning beam is a strip-shaped beam with an aspect ratio of 20:1 to 80:1. The two optical deflection devices deflect the beams within a certain aspect ratio range, optionally in combination with collimation and / or expansion, to form a strip-shaped scanning beam with a certain aspect ratio. This scanning beam can cover the length of a scanning sub-area within the field of view in one direction, thereby achieving regional scanning of the field of view.

[0237] 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.

[0238] 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 in different directions according to the aspect ratio requirements, such as Figure 4 In the figure, multiple light-emitting units 310 are spliced into a row along their length direction. Optionally, they can also be spliced into two or more rows, that is, multiple light-emitting units 310 are spliced into a row along their length direction. 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) can be used to control the light source to emit light according to a preset time sequence. The length of the generated light beam along the first direction is less than its length along the second direction. Therefore, 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.

[0239] The light-emitting unit 310 may be, for example but not limited to, at least one of a light-emitting structure such as a vertical cavity surface emitting laser (VCSEL), an edge emitting laser (EEL), a light emitting diode (LED), a laser diode (LD), or a fiber laser. The edge emitting laser may be a Fabry Perot (FP) laser, a distributed feedback (DFB) laser, or an electro-absorption modulated laser (EML), and the like, which is not limited in this application. For example, if the light-emitting unit 310 is an EEL, the light beam emitted by the EEL is a long and narrow beam. By splicing the EEL light-emitting units 310 along the long axis of the emitted light beam, a light beam meeting a preset aspect ratio can be emitted.

[0240] The first optical deflector 100 serves as a fine deflection device, and the second optical deflector 200 serves as a coarse deflection device to deflect the light beam. Specifically, the first optical deflector 100 sequentially deflects the light beam at finer angular intervals within a smaller deflection angle range, and the first optical deflector 100 sequentially deflects the light beam by a relatively small angle. The second optical deflector 200 deflects the light beam deflected by the first optical deflector 100 sequentially at coarser angular intervals within a larger deflection angle range in a time-sharing manner. In other words, the second optical deflector 200 deflects the light beam deflected by the first optical deflector 100 by a relatively large angle in a time-sharing manner, ultimately achieving a comprehensive scan of the field of view. Combining the fine and coarse deflection devices leverages the fine deflection device's fast response speed and high number of resolvable points to achieve detailed scanning within a narrow angular range. Leveraging the coarse deflection device's high diffraction efficiency and large deflection angle, the scanning range can be expanded to cover a wide field of view while using a smaller number of deflection angles. 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 first optical deflection device 100 can finely deflect the light beam by multiple first deflection angles within the vicinity of a second deflection angle coarsely deflected by the second optical deflection device 200. Ultimately, 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 by multiple different second deflection angles in the first and second directions. In other words, while the first optical deflection device 100 can deflect the light beam in one dimension, the second optical deflection device 200 can deflect the light beam in two dimensions. This reduces the number of deflection angles of the second optical deflection device 200 and allows for a thinner device. 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 this application does not limit this.

[0241] In some embodiments, the first optical deflection device 100 can optionally deflect the light beam periodically or non-periodically, or can deflect the light beam in a time-sharing manner in a certain sequence or simultaneously. Taking periodic time-sharing deflection as an example, the first optical deflection device 100 is configured to deflect the incident light beam in a predetermined sequence to a plurality of different first deflection angles 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 of the plurality of 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.

[0242] The first optical deflection device 100 is configured to sequentially deflect an incident light beam in a first direction by a plurality of different first deflection angles. The first optical deflection device 100 can deflect the light beam by a plurality of first deflection angles within a preset angular range. Specifically, the control device 600 can control the first optical deflection device 100 to generate a plurality of incident light beams at a plurality of first deflection angles within a preset angular range and at a preset deflection interval, and project the light beams onto the second optical deflection device 200. For example, within a range of -1.5 to +1.5 degrees, the light beam can be deflected by a plurality of first deflection angles spaced at regular intervals. The first deflection angles are a sequence of angles, such as -1.5, -1.0, -0.5, 0, 0.5, 1, 1.5, and so on, and the angular intervals can be set as desired. In some embodiments, the first optical deflection device 100 can repeatedly deflect the light beam by all or a portion of the plurality of first deflection angles according to a plurality of preset deflection cycles. A deflection cycle refers to the time required for the first optical deflection device 100 to deflect the light beam by the plurality of first deflection angles within the preset angular range. Alternatively, the deflection period refers to the time required for the first optical deflection device 100 to sequentially deflect the light beam by all or a portion of a plurality of pre-set first deflection angles. It should be understood that the durations of any two different deflection periods can be set to be the same or different; and 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 deflection period, the first optical deflection device 100 can repeatedly deflect the light beam by one or more of the first deflection angles two or more times. After completing deflection in one deflection period, the first optical deflection device 100 can enter the next deflection period and continue deflecting the light beam according to the number and order of the corresponding pre-set first deflection angles.

[0243] The first optical 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 at multiple different first deflection angles to project the incident light beam onto different positions on the second optical deflection device 200. The second optical deflection device 200 deflects the deflected light beams incident at different first deflection angles by the same second deflection angle to scan a corresponding scanning subarea within the field of view. Similarly, the second optical deflection device 200 deflects the light beams incident at different first deflection angles by multiple second deflection angles at each first deflection angle to scan multiple scanning subareas corresponding to the multiple different second deflection angles.

[0244] Optionally, the first optical deflection device 100 deflects the light beam at multiple first deflection angles within a deflection cycle, and the second optical deflection device 200 deflects the light beams deflected by the first optical deflection device 100 at multiple first deflection angles within the deflection cycle to the same or different second deflection angles. 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 within the deflection cycle.

[0245] It will be appreciated that in some embodiments, when completing a scan of the entire field of view, the first optical deflection device 100 and the second optical deflection device 200 can be configured to deflect the light beams at different first deflection angles and in what order, so that one scanning area is scanned first, then the next scanning area is scanned, and so on, until all scanning areas are scanned. Specifically, the second optical deflection device 200 can deflect light beams incident at different first deflection angles to the same second deflection angle within a single deflection cycle, thereby concentrating on scanning a corresponding scanning subarea within a single deflection cycle. This allows multiple deflection cycles to complete the scanning of multiple different scanning subareas.

[0246] See also Figure 2 As shown, the entire field of view can be divided into multiple scanning areas. Figure 2 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 the following: Figure 2 The scanning of the 16 scanning partitions shown in the figure corresponds to a second deflection angle for each scanning partition, that is, after the multiple first deflection angles deflected by the first optical deflection device 100 are deflected by the second optical deflection device 200 to the same second deflection angle, they can cover a scanning partition. Wherein, 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 scanning partitions corresponding to the 16 squares is completed.

[0247] In other embodiments, the second optical deflection device 200 can deflect a deflected light beam incident at different first deflection angles to two or more different second deflection angles within a single deflection cycle. In this case, instead of scanning a single scanning subarea within a single deflection cycle, the light beams are scanned in a skipped manner, corresponding to different positions along the deflection direction of the first optical deflection device 100 within two or more different scanning subareas. This allows for the scanning of all scanning subareas to be completed over multiple deflection cycles. For example, in this embodiment, because the light beams formed by the first and second optical deflection devices 100 and 200 scan scanning subareas corresponding to different second deflection angles within a single deflection cycle, the scanned positions are relatively far apart, thereby reducing crosstalk between adjacent scans.

[0248] See also Figure 3 As shown, the entire field of view can be divided into multiple scanning sub-areas, with a total of 16 scanning sub-areas, corresponding to the 16 grids in the figure. Within a deflection cycle, the second optical deflection device 200 can deflect the multiple light beams at the first deflection angles deflected by the first optical deflection device 100 to different second deflection angles, so as to alternately scan different scanning sub-areas. For example, within a first deflection cycle, the second optical deflection device 200 deflects the first light beam at the first deflection angle by the first second deflection angle to scan a small strip area in the first square of the first row; deflects the second light beam at the second first deflection angle by the second second deflection angle to scan a small strip area in the second square of the first row; .... Within a second deflection cycle, the second optical deflection device 200 deflects the first light beam at the first first deflection angle by the first second deflection angle to scan a small strip area in the second square of the first row; deflects the second light beam at the second first deflection angle by the second second deflection angle to scan a small strip area in the third square of the first row; .... Similarly, 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.

[0249] 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 having the AOD deflect the beam in the width direction of the beam can greatly reduce the number of angles of deflection of the LCPG in the first and second directions, for example Figure 2 and Figure 3 As shown, the deflection angles are 16, 8 in the horizontal direction and 2 in the vertical direction. The number of LCPG deflection angles 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 LCPG layers can also be reduced. For example, when the deflection angles are 16, four layers of LCPG are sufficient, and the LCPG can be made thinner and smaller in size.

[0250] In some embodiments, a specific structural example of the above-mentioned transmitting module is shown in Figure 5 As shown, a collimating device 400 is further included, which is configured to collimate the light beam before the light beam enters the first light deflecting 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.

[0251] The collimating device 400 can collimate the light beam emitted by the light source 300 in a first direction and a second direction perpendicular to each other, and the collimated light beam is then incident on the first light deflection device 100. 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 collimating 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 optical 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 source is 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 optical deflection device 100, and no strict collimation is required in other directions. The collimated light beam can meet the deflection requirements 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 naturally diffuse with a larger divergence angle in the non-deflection direction, which is convenient for the subsequent formation of a strip light beam.

[0252] The collimating device 400 may include at least one collimating lens. Optionally, to collimate the light beam to the required degree of collimation, the positional relationship between the collimating device 400 and the light source 300 may be configured based on the light beam collimation requirements. One optional configuration is to position the light source 300 on the focal plane of the collimating lens. When the collimating device 400 includes at least two collimating lenses, the focal planes of the at least two collimating lenses overlap.

[0253] 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 can be selected from lenses with different focal lengths to achieve output light beams with different collimations in different directions, wherein the cylindrical lens with a smaller focal length is arranged closer to the light source, and the cylindrical lens with a larger focal length is arranged relatively far away from the light source. The focal planes of the two cylindrical lenses can overlap, and the light source is arranged at the focal planes.

[0254] Optionally, the collimating device 400 includes a spherical lens configured to collimate the light beam along a first direction and a 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 based on the collimation requirements in the two directions to meet the collimation requirements in both directions. Optionally, the collimation of the collimated light beam can achieve the required collimation in at least the direction with the higher collimation requirement.

[0255] 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 both the first and second directions. In this case, collimation is performed simultaneously by the cylindrical lens and the spherical lens in the direction where high collimation is required, and collimation is performed simultaneously by the spherical lens in the direction where low collimation is required, 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 coincide, and the light source is disposed at the focal plane.

[0256] 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, where A > B. The first optical deflector 100 and the second optical deflector 200 are configured to deflect the light beam with an aspect ratio of B into a light beam with an aspect ratio of C, where C > B. In other words, 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 exiting the collimator, or incident on the first optical deflector, will decrease to B. After primary deflection by the first optical deflector and secondary deflection by the second optical deflector, the aspect ratio of the projected scanning light beam will increase again to C, forming a long strip of light.

[0257] 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 6 The vertical optical path and Figure 7 The horizontal optical path shown takes two cylindrical lenses as an example.

[0258] In the vertical direction, the light beam width V1 and the divergence angle θ1 of the light beam in the vertical direction (first direction) are collimated by a cylindrical lens with a focal length of F2. The beam waist diameter V2 in the first direction when the light beam enters the first optical deflection device 100, the divergence angle θ2 in the first direction when the light beam enters the first optical deflection device 100, and the focal length F2 of the collimating lens that collimates the light beam in the first direction satisfy the following relationships: θ2 = V1 / F2, and θ2V2 = θ1V1. The distance 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.

[0259] In the horizontal direction, the light source has a length H1 of light emitted in the horizontal direction (second direction), a divergence angle θ1 of light emitted in the horizontal direction (second direction), and is collimated by a cylindrical lens with a focal length F1. The beam waist diameter H2 in the second direction when the light beam enters the first light deflection device 100, the divergence angle θ2 in the second direction when the light beam enters 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 relationships: θ2 = H1 / F1, and θ2H2 = θ1H1. The distance between the optical center of the cylindrical lens with a focal length of F1 and the light source can be selected to be the focal length F1.

[0260] In some embodiments, when selecting a bar-shaped light source, H1>>V1 can be selected. Accordingly, since θ1~θ1, the appropriate lens focal lengths F1 and F2 can be selected to make θ2>>θ2. In this way, after passing through the subsequent spherical lens, the light spot will appear as a long bar in the far field.

[0261] In some embodiments, see Figure 5 As shown, the above-mentioned transmitting module also includes a deflection expanding 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.

[0262] 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 is the same as the deflection angle magnification of the deflected light beam in the deflection direction. That is, the polarization expanding device 500 can be arranged 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-emitting 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.

[0263] The polarization expanding device 500 may include at least one polarization expanding lens. The polarization expanding lens may be a single lens or a combination of two or more lenses. The polarization expanding lens may include at least one of a cylindrical lens, a spherical lens, a metalens, and a Fresnel lens, or any combination thereof. When the polarization expanding lens includes a combination of two or more lenses, the combination of the two or more lenses may be considered as a single lens.

[0264] The at least one polarization expander lens is configured to amplify the deflection angle of the light beam deflected by the first optical deflection device 100 in at least one of the first and second directions perpendicular to each other by a preset multiple. The polarization expander 500 can also amplify 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 expander lens is set according to the magnification of the deflection angle. When the polarization expander 500 includes two polarization expanders, one side focus of one polarization expander lens coincides with one side focus of the other polarization expander lens, and the magnification is the ratio of the focal lengths of the two polarization expanders.

[0265] The positional relationship between the first optical deflection device 100, the second optical deflection device 200, and the polarization expander 500 can be designed based on the parameters of each device. Optionally, the distance between the first polarization expander lens in the first optical deflection device 100 and the polarization expander 500 is equal to the focal length of the first polarization expander lens, and the distance between two adjacent polarization expanders is equal to the sum of the focal lengths of the two adjacent polarization expanders. This allows the light beam deflected by the first optical deflection device 100 to converge at its rear focal point after passing through the polarization expander lens and then further diverge, allowing the deflection angle of the light beam to be expanded to the desired angle within a shorter distance. This allows the second optical deflection device 200 to be positioned closer to the first optical deflection device 100.

[0266] 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.

[0267] 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 a first cylindrical lens group and a second cylindrical lens group; the first cylindrical lens group includes a first polarization expanding cylindrical lens and a 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 a third polarization expanding cylindrical lens and a 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.

[0268] Alternatively, the two polarization expanding lenses included in the polarization expanding device 500 may be single lenses. In one embodiment, the polarization expanding device 500 includes a first polarization expanding spherical lens and a second polarization expanding spherical lens, each configured to amplify the deflection angle of the light beam deflected by the first light deflection device in the first and second directions by a predetermined magnification, where the predetermined magnification 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. Using spherical lenses as the polarization expanding lenses can reduce the number of lenses used.

[0269] In some embodiments, see Figure 8a and Figure 8b As shown, the polarization expanding device 500 includes, for example, a first polarization expanding lens 1281 and a second polarization expanding lens 1282. The first polarization expanding lens 1281 and the second polarization expanding lens 1282 are arranged sequentially along the propagation direction of the light beam, with the focal point of one side of the first polarization expanding lens 1281 and the focal point of one side of the second polarization expanding lens 1282 being arranged to overlap with each other within the section between the first polarization expanding lens 1281 and the second polarization expanding lens 1282. That is, the light beam deflected by the first or second light deflecting device is first converged by the first polarization expanding lens 1281 onto the focal plane of the second polarization expanding lens 1282, and then deflected by the second polarization expanding lens 1282 to achieve amplification of the deflection angle.

[0270] For example, in Figure 8aIn the illustrated embodiment, both the first expander lens 1281 and the second expander lens 1282 have positive optical power. If the focal length of the first expander lens 1281 is F1 and the focal length of the second expander lens is F2, then the beam deflection angle magnification factor M by the expander 500 is M = F1 / F2. In other words, the angle of the beam deflected from the center of the field of view by the first or second optical deflector before entering the expander 500 is magnified M times after passing through the expander 500.

[0271] For example, in Figure 8b In the illustrated embodiment, the first expander lens 1281 has a positive optical focal length, and the second expander lens 1282 has a negative optical focal length. If the focal length of the first expander lens 1281 is F1 and the focal length of the second lens is F2, then the amplification factor M of the light beam deflection angle by the expander device 500 is M = F1 / F2. That is, the angle of the light beam deflected from the center of the field of view by the first optical deflection device or the second optical deflection device before entering the expander device 500 will be amplified M times after passing through the expander device 500.

[0272] It should be understood that the first polarization expander lens 1281 can be a single lens or a lens group including multiple lenses. Similarly, the second polarization expander lens 1282 can be a single lens or a lens group including multiple lenses.

[0273] It should be understood that the first polarization expander lens 1281 and the second polarization expander lens 1282 can both be spherical mirrors that are rotationally symmetric about the optical axis and are configured to amplify the deflection angle of the passing light beam in all directions by the same factor. For example, the first polarization expander lens 1281 and the second polarization expander lens 1282 can amplify the deflection angle of the passing light beam by a factor of M in both a first direction and a second direction, where the first direction is perpendicular to the second direction.

[0274] 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 this arrangement, 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 on 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 deflection 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 angular 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.

[0275] Taking the example of a deflection expander 500 positioned on the light-emitting side of the second optical deflection device 200, the first optical deflection device 100 is configured to deflect the light beam by a plurality of first deflection angles within a deflection cycle and project the deflected light beam onto a corresponding position on the second optical deflection device 200. The second optical deflection device 200 is configured to deflect the light beam by a predetermined second deflection angle within the deflection cycle. The deflection expander 500 is configured to amplify the deflection angle of the light beam deflected by the second optical deflection device 200 in the corresponding deflection direction by a predetermined multiple to project a scanning beam. This arrangement increases the deflection angle of the light beam deflected by the second optical deflection device and also allows for a more compact transmitter module.

[0276] In the two aforementioned configurations, the deflection expander 500 is positioned between the first optical deflection device 100 and the second optical deflection device 200, thereby increasing the deflection angle of the light beam deflected by the first optical deflection device. The deflection expander 500 allows light beams with adjacent deflection angles deflected by the first optical deflection device to be distinguished within a minimum distance, thereby shortening the distance between the second optical deflection device and the first optical deflection device, and making the overall structure of the transmitter module smaller. The deflection expander 500 is positioned on the light-emitting side of the second optical deflection device 200, thereby increasing the deflection angle of the light beam deflected by the second optical deflection device. The deflection expander 500 allows light beams with adjacent deflection angles deflected by the second optical deflection device to be distinguished within a minimum distance, thereby reducing the deflection angle requirement for the first optical deflection device when deflecting the light beam. This shortens the distance between the second optical deflection device and the first optical deflection device, and making the overall structure of the transmitter 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 on 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 polarization 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 angular 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.

[0277] In the above-mentioned transmitting module, the deflection accuracy of the first light deflection device 100 for the light beam is higher than the deflection accuracy of the second light deflection device 200 for the light beam.

[0278] In some embodiments, the first optical deflection device 100 deflects the light beam at a higher speed than the second optical deflection device 200. For approximately each second deflection angle of coarse deflection by the second optical deflection device 200, the first optical deflection device 100 performs multiple fine deflections of the first deflection angle. Therefore, in a single scan of the entire field of view, the number of fine deflections performed by the first optical deflection device 100 is several times greater than the number of coarse deflections performed by the second optical deflection device 200. Therefore, using the faster deflection speed of the first optical deflection device 100 to perform a higher number of fine deflections can reduce the optical deflection time required for scanning.

[0279] 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.

[0280] In some embodiments, the divergence angle of the strip-shaped light beam formed by the deflection expanding device 500 along the second direction is greater than or equal to the angular interval between two adjacent second deflection angles along the second direction by the second light deflecting device 200. This allows the edges of two adjacent light beams deflected at two adjacent second deflection angles in the second direction to slightly overlap, thereby ensuring full coverage of the scanning area and preventing any missed scans.

[0281] In some embodiments, the deflection angle range of the light beam deflected in the first direction by the first light deflector 100 is greater than or equal to the angular interval between two adjacent second deflection angles in the first direction by the second light deflector 200. This allows the edges of the scanning area covered by the light beams deflected at two adjacent second deflection angles in the first direction to slightly overlap, thereby ensuring full coverage of the scanning area and preventing any missed scans.

[0282] In some embodiments, when the light beam emitted by the light source is linearly polarized, the emission module further includes a half-wave plate disposed between the collimator 400 and the first light deflector 100 to change the polarization direction of the light beam. The optical axis of the half-wave plate is perpendicular to the direction of the light beam emitted by the collimator 400, and the electric field direction of the linearly polarized light forms a 45-degree angle with the fast axis of the half-wave plate, or the electric field direction of the linearly polarized light forms a 45-degree angle with the slow axis of the half-wave plate.

[0283] In the scheme where the first optical deflection device 100 is combined with the second optical deflection device 200 to deflect the light beam, in some cases, it is necessary to rotate the polarization direction of the light beam. In this case, this can be achieved by setting a 1 / 2 wave plate between the collimator 400 and the first optical 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 linearly polarized light, with the electric field direction parallel to the slow axis direction, for example, horizontal in this application. On the other hand, when designing the first optical deflection device 100, it is generally required that the polarization direction of the incident light is parallel to the ultrasonic direction, for example, vertical 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. Polarization 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.

[0284] In some embodiments, the control device 600 of the emission module can be an independent device, and the control of the first light deflection device 100 and the second light deflection device 200 can be realized by an independent device. The control device 600 can also be a discrete device, see Figure 5 As shown, the control device 600 includes a first control unit 110 and a second control unit 230;

[0285] The first control unit 110 is configured to control the first optical deflection device 100 to deflect a plurality of different first deflection angles in a time-sharing manner within a deflection period, and to direct the light beam at each first deflection angle to be incident on the second optical deflection device 200;

[0286] The second control unit 230 is used to control the second light deflection device 200 to receive the light beam in a time-division manner and deflect the light beam to a desired second deflection angle.

[0287] In the aforementioned transmitting module, the light beam is deflected at multiple different angles by the first and second optical deflection devices 100 and 200 in a time-sharing manner to scan a predetermined field of view. The predetermined field of view is shorter in the first direction than in the second direction. By aligning the second direction, in which the longer strip beam formed by the secondary deflection is aligned with the longer direction of the entire field of view to be scanned, the number of angles that the second optical deflection device must deflect the strip beam along the second direction is reduced, thereby reducing the size and cost of the second optical deflector and shortening the beam deflection time required for scanning.

[0288] In practical applications, the second optical 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; deflecting 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 multiple light beams with different first deflection angles to the same second deflection angle within one deflection period to complete the scanning of a corresponding scanning partition in the field of view; different deflection periods have different second deflection angles for the deflection of the multiple light beams with different first deflection angles; or within one deflection period, deflect multiple light beams with different first deflection angles to one of multiple different second deflection angles to scan partial areas in the corresponding scanning partitions; wherein, within one deflection period, multiple light beams with different first deflection angles are deflected to the same or different second deflection angles; and the light beams with each first deflection angle are deflected to different second deflection angles in different deflection periods.

[0289] The first optical deflection device 100 may be, for example but not limited to, an acousto-optic deflector (AOD). The AOD can deflect a light beam according to a preset acoustic wave frequency. The AOD may include an input aperture, an acousto-optic crystal, an acoustic wave generator, and an output aperture. Configuring the acousto-optic crystal according to a specific scheme can achieve quasi-continuous deflection of one-dimensional or two-dimensional light, with the deflection response time being proportional to the width of the light beam within the crystal. A control device 600 is configured to apply a drive signal to the acoustic wave generator of the first optical deflection device 100. The drive signal controls the frequency of the acoustic waves applied by the acoustic wave generator to the acousto-optic crystal of the first optical deflection device 100, thereby varying the deflection angle of the light beam by the first optical deflection device 100.

[0290] The second light deflection device 200 is, for example but not limited to, a liquid crystal polarization grating. By adjusting the arrangement 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, deflection of 2 degrees in the first direction and 8 degrees in the second direction is used as an example. In actual applications, the number of deflection angles in each direction can be 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 plate included in the liquid crystal polarization grating is nematic liquid crystal or blue phase liquid crystal. Using blue phase liquid crystal can further increase the speed of the second light deflection device in adjusting the deflection angle, shortening the deflection angle adjustment time.

[0291] In the above-mentioned transmitting module, the incident light beam of each device is different according to the positional relationship thereof. For example, when the collimating device 400 and the polarization expanding device 500 are not included, the incident light beam of the first optical deflection device 100 is the light beam emitted by the light source, and the incident light beam of the second optical deflection device 200 is the light beam deflected by the first optical deflection device 100. For another example, when the collimator 400 is not included but the polarization expander 500 is included, if the polarization expander 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 expander 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 expander 500; if the polarization expander 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 expander 500 is the light beam deflected by the second optical deflection device 200. For another example, when the deflection expander 500 is not included but the collimator 400 is included, the incident light beam to the collimator 400 is the light beam emitted by the light source, the light beam collimated by the first light deflector 100 is the light beam, and the incident light beam to the second light deflector 200 is the light beam deflected by the first light deflector 100. The same applies to other arrangements.

[0292] The transmitting module of the present invention increases the number of deflection angles the beam undergoes as it scans the entire field of view (FOV), thereby reducing the divergence angle of the beam after deflection by the optical deflection device. This is because the beam needs to cover the entire angular range of the FOV after a predetermined number of deflections. A greater number of deflection angles requires a smaller divergence angle. Reducing the divergence angle increases the beam's power per unit divergence angle, which helps improve the detection range of the LiDAR.

[0293] The above-mentioned emission module can be designed with specific design schemes as needed. When designing different schemes, the aspect ratio of the scanning field of view, the length ratio of the scanning spot reaching a distant point, the splicing method of the light source, etc. can be determined first. These can all be adjusted and designed as needed. Then, based on parameters such as the liquid crystal response time of the liquid crystal polarization grating, the vertical and horizontal light paths are designed, and the number and type of lenses in the light path are selected, such as the number of collimating lenses and polarization expander lenses to be used, and whether to use cylindrical lenses or spherical lenses; as well as the positional relationship between the various components. This achieves the goal of collimating a light beam with a certain aspect ratio emitted by the light source, collimating it, and then collimating it into a beam with a relatively small aspect ratio. After entering the first light deflection device 100, the first light deflection device 100 deflects it in the first direction, and the second light deflection device 200 deflects it in the first and second directions. Polarization expanders 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 beam with a relatively large aspect ratio. The following are several design examples:

[0294] Design 1

[0295] 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 4 shown.

[0296] Design Scheme 1 assumes that the liquid crystal response time of the liquid crystal polarization grating is 5 ms. The collimating element 400 uses collimating lenses F1 and F2, the first optical deflection element 100 uses an AOD, the second optical deflection element 200 uses a partitioned LCPG module, and the polarization expansion element 500 uses polarization expansion lenses F3, F4, F5, and F6.

[0297] In the vertical direction, the collimating lens F2 is used to collimate the beam, and the expanding lenses F3 and F4 are used to expand the beam. In the horizontal direction, the collimating lens F1 is used to collimate the beam, and the expanding lenses F5 and F6 are used to expand the beam.

[0298] The components of this design are selected in Table 1 below:

[0299] Table 1

[0300] Scanning spot shape Greater than 10(H)*1(V) AOD clear aperture Within the range of 1(H)*5(V) to 5(H)*1(V) LCPG module light deflection unit quantity 3(H)*1(V) LCPG module deflection angle number 8(H)*2(V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Cylindrical lenses F3, F4, F5, F6

[0301] 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.

[0302] The length L from the light source to the second light deflection device (LCPG module) is calculated by the following formula:

[0303] L = 2*(F1+F3+F4)+d;

[0304] F1, F3, and F4 are the focal lengths of lenses F1, F3, and F4, respectively. d is the distance from the back focal plane of lens F4 to the LCPG. The calculation formula for d is:

[0305] d*2*tan(Θv / 2)≥m*{θv 2 *d+Wv 2} 1 / 2 ,

[0306] Where Θv is the vertical deflection angle of the beam after passing through the AOD and the polarization expanding lens group, θv is the vertical divergence angle of the beam at this time, and Wv is the vertical beam waist diameter of the 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 for Wv is as follows:

[0307] Wv=Wv0*θv0 / θv

[0308] Wv0 and θv0 are the waist diameter and divergence angle of the laser beam emitted by the laser light source in the vertical direction.

[0309] The total dimensions of LCPG in horizontal and vertical directions are

[0310] Lh=d*2*tan(Θh / 2)

[0311] Lv=d*2*tan(Θv / 2)

[0312] Θh is the horizontal divergence angle of the laser beam incident on the LCPG module.

[0313] The vertical optical path is designed as follows:

[0314] 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.

[0315] The diffracted light beam out of the AOD 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.

[0316] 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.

[0317] The LCPG module response time is set at 5ms. During spot scanning, the deflection sections within the LCPG module illuminated by the spot cannot adjust their deflection direction. To complete 16 deflections (2 x 8 pixels) within 100ms, each layer of the liquid crystal half-wave plate must be divided into 10 equal sections along the vertical direction.

[0318] according to Figure 6 and Figure 7 The optical path shown can be used to calculate the vertical size of the LCPG module and the distance between the LCPG and the F4 back focal plane.

[0319] The horizontal optical path is designed as follows:

[0320] In the horizontal direction, the AOD does not deflect the incident laser beam. The laser beam exiting the AOD is first contracted by the horizontal cylindrical lens group F5 and F6 and the divergence angle is increased by 2 times.

[0321] Then it passes through the LCPG module and deflects in 8 directions in the horizontal direction to cover the horizontal scanning area.

[0322] Based on the LCPG response time of 5ms, the placement of the LCPG has been calculated in the above vertical optical path design, from which the horizontal size of the LCPG can be calculated.

[0323] Design 2

[0324] The difference between this solution and Design Solution 1 is that the horizontal optical path configuration is different.

[0325] 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.

[0326] 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.

[0327] The components for this design are listed in Table 2 below:

[0328] Table 2

[0329] Scanning spot shape Greater than 10(H)*1(V) AOD clear aperture Within the range of 1(H)*5(V) to 5(H)*1(V) LCPG module light deflection unit quantity 3(H)*1(V) LCPG module deflection angle number 8(H)*2(V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Cylindrical lens F3, F4

[0330] The length L from the light source to the second light deflection device (LCPG module) in this solution is consistent with that in Design Solution 1.

[0331] The vertical optical path design of this design scheme is the same as that of Scheme 1, and the horizontal optical path design is as follows:

[0332] In the horizontal direction, the AOD does not deflect the incident laser beam. The horizontal divergence angle of the AOD is a specified degree, and there is no horizontal beam reduction lens group to expand the beam.

[0333] Then it passes through the LCPG module and deflects in 8 directions in the horizontal direction to cover the horizontal scanning area.

[0334] Assuming the LCPG module response time is 5ms, the placement of the LCPG has been calculated in the vertical optical path design, from which the horizontal size of the LCPG can be calculated.

[0335] The structural difference between Solution 2 and Solution 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.

[0336] Technical Difference: Because the cylindrical lens combination F5 and F6, which only expands the beam horizontally, may affect the vertical divergence of the beam, Solution 2 omits cylindrical lenses F5 and F6. However, the size of the LCPG module must be increased accordingly to receive the full beam. Solution 1 and Solution 2 share the same distance between the light source and the LCPG module, so there is no difference in system size.

[0337] Design 3

[0338] 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 with instantaneous power that meet the requirements, spliced along the long axis (horizontal) direction.

[0339] Assuming the response time of the liquid crystal is 5ms, the aperture size of the AOD is 8*4 or 8*3.

[0340] The collimating lens is composed of two cylindrical lenses F1 and F2, and the expanding lens is composed of two spherical lenses F3 and F4.

[0341] The components for this design are listed in Table 3 below:

[0342] Table 3

[0343] Scanning spot shape Greater than 10(H)*1(V) AOD clear aperture Within the range of 1(H)*5(V) to 5(H)*1(V) LCPG module light deflection unit quantity 3(H)*1(V) LCPG module deflection angle number 8(H)*2(V) Collimating lens Cylindrical lenses F1, F2 Polarization expansion lens Spherical lens F3, F4

[0344] In design solution 3, the LCPG module has four layers, that is, four optical deflection units realize deflection at 16 separation angles.

[0345] 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.

[0346] 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.

[0347] The collimated beam enters the AOD. In the vertical direction, the beam divergence angle is θ2, and the beam waist diameter is V2, satisfying the relationships θ2 = V1 / F2 and θ2V2 = θ1V1. Similarly, in the horizontal direction, the beam divergence angle is θ2, and the beam waist diameter is H2, satisfying the relationships θ2 = H1 / F1 and θ2H2 = θ1H1.

[0348] In this solution, a long, strip-shaped EEL light source is typically chosen. For example, H1>>V1. Accordingly, since θ1~θ1, the appropriate lens focal lengths F1 and F2 can be selected to ensure θ2<<θ2. This way, after passing through the subsequent spherical lens, the light spot will appear as a long strip in the far field.

[0349] To ensure maximum light energy passes through the AOD, the vertical aperture 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 θ2<<θ2, so after collimation, the laser beam is nearly parallel in the vertical direction, while still having 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 vertical aperture of the AOD can be minimized to V2.

[0350] The AOD is configured to deflect the light beam in the vertical direction. In the collimating device 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 θ2 ≥ 3° can be allowed.

[0351] The light beam exits the AOD and enters the polarization expansion device, which amplifies the deflection angle of the light beam emitted by the AOD. This solution takes the Kepler lens group as an example. The focal lengths of the two polarization expansion lenses are F3 and F4, respectively, and the polarization expansion ratio is F3 / F4. If the AOD deflects the light beam within a range of +-1.5 degrees, the deflection range becomes +-(1.5*F3 / F4) degrees after passing through the AOD. Simultaneously, the divergence angles of the light beam, θ2, θ2, are also expanded by F3 / F4 times accordingly. The distance between the AOD and the first polarization expansion lens F3 is its focal length F3, and the interval between the polarization expansion lens groups 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.

[0352] The LCPG module includes at least one LCPG unit, and each LCPG unit includes a liquid crystal half-wave plate and an LCPG sheet.

[0353] The thickness of the liquid crystal half-wave plate and LCPG is primarily determined by the thickness of the glass substrate. In practice, the glass substrate thickness is typically << 1mm, and the total thickness of the multilayer liquid crystal is <1mm. In this case, the thickness of the LCPG can be ignored in optical path design.

[0354] The LCPG sheet in this solution can be either passive LCPG or active LCPG. The difference between the two is:

[0355] 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 achieve light beam deflection during operation.

[0356] 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.

[0357] In this solution, the LCPG units that deflect the light beam along the deflection direction with fewer deflection angles can be placed earlier in the optical path to improve the diffraction efficiency of the passing light beam. However, the corresponding beam deflection function can also be achieved without following the above order requirements.

[0358] The above are several design examples of the emission module. In actual applications, the optical path design and device selection of the emission module can be designed according to scanning needs.

[0359] Several optional structures of the transmitting module of the present invention are described below through specific embodiments.

[0360] Example 2

[0361] The structure diagram of the transmitting module provided in the second embodiment of the present invention is shown in FIG. Figure 9 As shown, the three-dimensional structure diagram is shown in Figure 5 As shown, the transmitting module includes a light source 300, a collimating device 400, a first optical deflection device 100, a deflection expansion device 500, a second optical deflection device 200, and a control device 600. In this embodiment, the first optical deflection device 100 deflects the light beam in one dimension in the first direction, and the second optical deflection device 200 deflects the light beam in two dimensions in the first direction and the second direction. In this embodiment, the second optical deflection device 200 adopts a partitioned structure. In this transmitting module:

[0362] A light source 300 is configured to emit a light beam, wherein the length of the light beam along the first direction is shorter than the length along the second direction;

[0363] The collimating device 400 is configured to collimate the light beam before the light beam enters the first light deflecting device 100;

[0364] 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 one deflection period;

[0365] 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 before the light beam is incident on the second light deflection device 200;

[0366] 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;

[0367] 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.

[0368] The collimating device 400 can be a collimating lens, the first light deflecting device 100 can be an AOD, the polarization expanding device 500 can be a polarization expanding lens, and the second light deflecting device 200 can be an LCPG module. Figure 6 As shown, the optical path in the second direction (horizontal direction) is shown in FIG. Figure 7 shown.

[0369] 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 4 As shown, the light source 300 may include a plurality of light emitting units 310 .

[0370] The collimator 400 collimates the light beam in both the first and second directions. A light source control unit can be used to control the light source to emit light in a preset time sequence. The collimation degree in the first direction is required to be higher, thereby reducing the divergence angle of the light beam in the first direction. 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 are inversely proportional. Therefore, a higher degree of collimation can be achieved in the width direction of the strip light beam than in the length direction. Figure 6 and Figure 7 As shown, two collimating lenses collimate the light beam in a first direction and a second direction respectively. The figure takes two cylindrical lenses as an example.

[0371] The first light deflector 100 deflects the light beam in a first direction and can deflect the light beam at multiple first deflection angles within a preset angle range. The multiple first deflection angles can have preset angle intervals. The first light deflector 100 can deflect the light beam according to a preset time sequence.

[0372] 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 6 As shown, the two polarization expanding lenses expand the light beam in the first direction. After the light beam emitted from the first optical deflection device 100 passes through the two polarization expanding lenses, the deflection angle in the first direction is increased. The expanded light beam is then projected onto the corresponding position of the second optical deflection device 200. Figure 7 As shown, the two expanding lenses expand the light beam in the second direction. 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 onto the corresponding position of the second optical deflection device 200.

[0373] 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.

[0374] The second light deflection device 200 may adopt a partitioned structure or a non-partitioned structure.

[0375] In this embodiment, the second optical deflection device 200 employs a partitioned structure as an example. This partitioned structure addresses the long wait time for deflection angle switching and slow angle adjustment, which impacts the LiDAR scanning and detection frame rate, when using liquid crystal polarization gratings for beam deflection. By dividing the second optical deflection device into different deflection zones, beams with different first deflection angles are expanded and projected onto different deflection zones of the second optical deflection device 200. Each deflection zone can then use its unexposed time to adjust its deflection angle. This eliminates the need for the scanning system to wait for the optical deflection device to adjust its state before changing the deflection angle, allowing for continuous scanning. This eliminates the wait time for angle adjustment and improves switching speed, allowing the required detection frame rate to be met while increasing the number of beam deflection angles. This design achieves a high frame rate, a wide field of view, and long-range measurement capabilities, meeting the requirements of applications such as automotive LiDAR. In this embodiment, the deflection zones in the second optical deflection device 200 are arranged along the first direction.

[0376] The structure of the second light deflection device 200 with a partitioned structure is shown in FIG. Figure 10a 、 10b, 10c and 10d. The second light deflection device 200 may include a plurality of deflection partitions 212, each of which can independently adjust the deflection angle, that is, each deflection partition 212 can independently adjust the deflection angle of the incident light beam; in the case of a partition structure:

[0377] 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 zones 212 of the second light deflection device 200;

[0378] a plurality of deflection sub-areas 212 configured so that the deflection sub-area 212 currently being scanned deflects the incident light beam at a second deflection angle required by the deflection sub-area 212;

[0379] 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 current deflection cycle is scanned by the incident light beam and before the next deflection cycle is scanned by the incident light beam.

[0380] The control device 600 can be used to control the first optical deflection device 100 to deflect the incident light beam by multiple different first deflection angles within a deflection cycle, corresponding to the deflection zones of the second optical deflection device 200. It can also be used to control the currently scanned deflection zone of the second optical deflection device 200 to deflect the incident light beam by a desired second deflection angle. It can also be used to control at least one deflection zone 212 that is not currently scanned to adjust its deflection angle relative to the light beam, so that the deflection angle of the at least one deflection zone 212 relative to the incident light beam is adjusted to the desired second deflection angle relative to the next deflection cycle after the incident light beam scan ends in the current deflection cycle and before the incident light beam scan begins in the next deflection cycle. Optionally, the control device 600 is specifically configured to concurrently execute the following control processes: controlling the currently scanned deflection zone of the second optical deflection device 200 to deflect the incident light beam, and controlling at least one deflection zone 212 that is not currently scanned to adjust its deflection angle relative to the light beam. That is, while the currently scanned deflection partition 212 of the second light deflecting device 200 deflects the incident light beam, at least one currently unscanned deflection partition 212 can adjust its deflection angle of the light beam under the control of the control device 600.

[0381] Within a deflection cycle, the control device 600 controls the first optical deflection device 100 to time-share deflect the light beam to a plurality of different first deflection angles, so that the plurality of deflection sub-areas 212 receiving the incident light beams and deflecting the incident light beams are received in a time-shared manner corresponding to the plurality of deflection sub-areas 212 incident on the second optical deflection device 200. The deflection cycle is the time required for the plurality of deflection sub-areas 212 to be scanned once by the incident light beams at the plurality of different first deflection angles. In other words, the deflection cycle is the time required for the incident light beams at the plurality of different first deflection angles to traverse and scan the plurality of deflection sub-areas 212. In this case, within a deflection cycle, all incident light beams at the plurality of different first deflection angles will scan all deflection sub-areas 212, i.e., each deflection sub-area 212 will be scanned without being missed.

[0382] Alternatively, 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. Within one deflection period, some of the deflection partitions 212 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 can be the same or different, and accordingly, the incident light beam of the specified portion of the first deflection angles can be the same or different.

[0383] During each deflection cycle, the control device 600 can control the first optical deflection device 100 to generate multiple incident light beams at different first deflection angles within a preset angle range and at a preset deflection time interval, and project them onto corresponding deflection sub-areas of the second optical deflection device 200. During a deflection cycle, the control device 600 can control the first optical deflection device 100 to deflect the incident light beam to multiple different first deflection angles in a time-sharing manner. The multiple incident light beams at different first deflection angles are incident on multiple deflection sub-areas in a time-sharing manner, and the multiple deflection sub-areas of the second optical deflection device 200 receive and deflect the incident light beams in a time-sharing manner. Furthermore, the first optical deflection device 100 is configured to sequentially direct the multiple incident light beams at different first deflection angles to corresponding deflection sub-areas of the second optical deflection device 200 in a preset order within a deflection cycle. Each deflection sub-area 212 is configured to deflect the incident light beam to a corresponding second deflection angle within a deflection cycle.

[0384] The above-mentioned second optical deflection device 200 can realize the control of at least one deflection partition 212 through the control device 600 to complete the adjustment of the second deflection angle once within the scanning interval of two adjacent deflection cycles, 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 light 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.

[0385] In one deflection cycle, a plurality of 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 the plurality of incident light beams with different first deflection angles can be pre-set and can be achieved by the control of the control device 600. Optionally, the deflection angles of the plurality of light beams with different first deflection angles vary from large to small in the first direction, or from small to large, or according to a preset random rule. Optionally, the deflection angles of the plurality of light beams with different first deflection angles can vary 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 the plurality of light beams with different first deflection angles can vary 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 at the multiple different first deflection angles of the light deflection unit group can also vary according to a preset random rule, for example, randomly varying from -1.5, 1, -0.5, 0, -1.0, 0.5, and 1.5. Within different deflection periods, the incident order of the incident light beams can be the same or different.

[0386] In the above-mentioned second optical deflection device 200, the multiple deflection partitions 212 are configured to deflect the incident light beam at multiple second deflection angles in one deflection cycle, which 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.

[0387] In the second light deflection device 200, a deflection subarea 212 can be configured to receive at least one incident light beam with a first deflection angle. Alternatively, a deflection subarea 212 can be configured to sequentially receive one, two, or more incident light beams with different first deflection angles within a deflection cycle.

[0388] In the 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 at multiple different first deflection angles. The multiple deflection partitions 212 can be arranged one-dimensionally along a direction, or arranged in a two-dimensional array. Their arrangement direction can be consistent with the scanning direction of the incident light beam at 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, arrangement along a direction is taken as an example.

[0389] When the incident light beam is a strip-shaped light beam having 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 cycle, 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 Figure 10a 、 10bAs shown in Figures 10c, 10d, and 10e, multiple deflection subareas 212 are arranged vertically. The deflection subareas 212 can be rectangular with an aspect ratio greater than a set threshold. The width of the deflection subareas is consistent with the scanning direction of the incident light beams at the multiple different first deflection angles. That is, the width of the deflection subareas is along the first direction, and the length of the deflection subareas is along the second direction.

[0390] In the second optical deflection device 200, the multiple deflection sub-areas 212 are configured such that each deflection sub-area 212 receives the same number of incident light beams, different numbers of incident light beams, or some numbers of the same and some numbers of different light beams. Accordingly, the widths of the multiple deflection sub-areas 212 are the same, different numbers of incident light beams, or some numbers of the same and some numbers of different light beams. The beam incident surfaces of the deflection sub-areas are rectangular with an aspect ratio greater than a predetermined threshold. The widths of the deflection sub-areas are aligned with the scanning directions of the light beams at the multiple different first deflection angles. The width of each deflection sub-area 212 is determined based on the number of incident light beams received and the width of the incident light beams.

[0391] Each deflection sub-area 212 can be configured to receive the same number of incident light beams. For example, each deflection sub-area 212 receives one incident light beam, i.e., there is a one-to-one correspondence between the incident light beams in the deflection sub-area 212, or each deflection sub-area 212 receives two or more incident light beams, with a one-to-two or one-to-many relationship between the deflection sub-area 212 and the incident light beams. In this case, the width of each deflection sub-area 212 can be the same, and the width of each deflection sub-area 212 is equal to the sum of the widths of the corresponding received light beams. For example, in a one-to-two relationship, the width of a deflection sub-area 212 is equal to the sum of the widths of the two light beams.

[0392] Each deflection sub-area 212 may receive a different number of incident beams. For example, the first deflection sub-area 212 receives one incident beam, the second deflection sub-area 212 receives two incident beams, the third deflection sub-area 212 receives three incident beams, and so on. In this case, the width of each deflection sub-area 212 is different, and the width of each deflection sub-area 212 is equal to the sum of the widths of the corresponding received beams.

[0393] The number of incident light beams received by each deflection sub-area 212 may be partially the same but partially different. For example, the first deflection sub-area 212 receives one incident light beam, the second deflection sub-area 212 receives two incident light beams, the third deflection sub-area 212 receives one incident light beam, the fourth deflection sub-area 212 receives two incident light beams, and so on. In this case, the width of each deflection sub-area 212 is partially the same but partially different, and the width of each deflection sub-area 212 is equal to the sum of the widths of the light beams received by it.

[0394] In some optional embodiments, the control device 600 can determine whether the deflection angle of each deflection partition 212 can be adjusted based on the scanning state of the 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 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 begin adjusting 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, thereby better ensuring that the angle can be adjusted in a timely manner. The non-scanning state refers to a state in which there is no incident light beam and no beam deflection is required.

[0395] In practical applications, the deflection sub-area 212 currently scanned by the incident light beam can be determined as a deflection sub-area in the scanning state, and the remaining deflection sub-areas 212 can be determined as deflection sub-areas in the non-scanning state. In other words, if a deflection sub-area is the deflection sub-area currently scanned by the incident light beam, the deflection sub-area is determined to be in the scanning state; otherwise, the deflection sub-area is determined to be in the non-scanning state.

[0396] Optionally, the deflection partition 212 currently scanned by the incident light beam and the next deflection partition 212 to be scanned can 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 incident light beam and the next deflection partition 212 to be scanned; 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 non-adjacent deflection partitions in position. That is, if a deflection partition 212 is the deflection partition currently scanned by the incident light beam or the next deflection partition to be scanned, the deflection partition 212 is determined to be in a scanning state; otherwise, the deflection partition 212 is determined to be 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 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.

[0397] Since the incident light beam deflected by the first light deflection device 100 can impinge on different positions of the second light deflection device 200, and different positions of the second light deflection device 200 correspond to different deflection sub-zones, it is possible to determine which deflection sub-zones are in a scanning state and which are in a non-scanning state based on the incident light beam's scanning position on the second light deflection device 200. The control device 600 is specifically configured to determine which deflection sub-zones 212 are currently in a scanning state and which are currently in a non-scanning state based on the scanning position of the incident light beam on the second light deflection device 200. For a deflection sub-zone 212 in a non-scanning state, if the scanning order of the deflection sub-zone 212 is before that of the deflection sub-zone 212 in a scanning state, it is considered that the deflection sub-zone has completed beam deflection for the current deflection cycle, and the deflection angle of the light beam of the deflection sub-zone 212 can be adjusted to the second deflection angle required for the next deflection cycle.

[0398] Adjusting the deflection angle of each deflection sub-area in the second optical deflection device 200 can be achieved by changing the voltage on the electrodes. Different deflection devices have different principles for deflecting light beams. For optical deflection devices that change the deflection angle by changing the refractive index, when the second optical deflection device 200 has a non-partitioned structure, the control device 600 is used to control the voltage applied to the electrodes of the second optical deflection device 200 to adjust the refractive index of the medium in the second optical deflection device 200 with respect to the incident light beam, thereby adjusting the deflection angle of the incident light beam by the second optical deflection device 200. When the second optical deflection device 200 has a partitioned structure, the control device 600 is used to control the voltage applied to the electrodes of each deflection sub-area 212 to adjust the refractive index of the medium in the deflection sub-area 212 with respect to the incident light beam, thereby adjusting the deflection angle of the incident light beam by the deflection sub-area 212.

[0399] For example: when the second light deflection device 200 adopts a liquid crystal polarization grating and has 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 has 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.

[0400] In some optional embodiments, see Figure 10a 、 10bAs shown in Figures 10c and 10d, the second optical deflection device 200 includes at least one optical deflection unit 210, which includes multiple deflection sub-sections 2121. The deflection sub-sections 212 include deflection sub-sections 2121 corresponding to positions in at least one optical deflection unit 210. When the second optical deflection device 200 includes one optical deflection unit 210, the deflection sub-section is one deflection sub-section 2121 on the one optical deflection unit 210. When the second optical deflection device 200 includes two optical deflection units 210, the deflection sub-section includes two deflection sub-sections 2121 corresponding to positions in the two optical deflection units 210. When the second optical deflection device 200 includes multiple optical deflection units 210, the deflection sub-sections 212 include multiple deflection sub-sections 2121 corresponding to positions in the multiple optical deflection units 210. The 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 second deflection angles. Figure 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 relationship between the number N of optical deflection units 210 and the required number M of deflection angles satisfies M=2. N .

[0401] The optical deflection unit 210 includes deflection sub-sections 2121 that can independently adjust the deflection angle of the light beam. Because the optical deflection unit 210 includes multiple deflection sub-sections 2121 with independently controllable deflection angles, light beams with different deflection angles can be incident on each of the deflection sub-sections 2121 and deflected. Therefore, the deflection angle of the light beam can be adjusted by utilizing the time when the deflection sub-section 2121 is not being scanned. When the second optical deflection device 200 includes at least one optical deflection unit 210, the control device 600 is specifically configured to control the voltages at the electrodes at both ends of each deflection sub-section 2121. By changing the voltages at the electrodes at both ends of at least one deflection sub-section 2121, the deflection angle of the at least one deflection sub-section 2121 with respect to the incident light beam is changed, thereby changing the second deflection angle of the corresponding deflection sub-section 212 with respect to the incident light beam. In other words, by adjusting the deflection angle of some or all of the multiple deflection sub-sections 2121 with respect to the incident light beam, the second deflection angle of the entire deflection sub-section 212 with respect to the incident light beam is changed.

[0402] The second optical deflection device 200 can angularly deflect the incident light beam in one direction or in two different directions. When deflection of the light beam only needs to be in one direction, the second optical deflection device 200 includes at least one optical deflection unit 210 to deflect the incident light beam in the same direction. In this case, the number of optical deflection units 210 is determined by the number of second deflection angles required, and can be one, two, or more.

[0403] 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.

[0404] Optionally, the light deflection unit group 220 with a smaller number of light beam deflection angles is set at a position relatively closer to the light incident side. This can achieve a better deflection effect. For example Figure 10a 、 10b , 10c and 10d, the optical deflection unit group 220 for deflecting the light in the first direction includes a light deflection unit 210 placed on the far left, achieving deflection at two angles in the first direction. Figure 6 The optical path diagram 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. Figure 7 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 the light beam at eight different angles in the second direction. Figure 7 Only three angles are shown. Placing the optical deflection unit 210, which deflects the light beam along a direction with fewer deflection angles, closer to the front of the optical path can improve the diffraction efficiency of the passing light beam. The corresponding beam deflection function can also be achieved without following the above order.

[0405] 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 of 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.

[0406] In some optional embodiments, the light deflection unit 210, for example but not limited to, uses a liquid crystal polarization grating. The liquid crystal polarization grating can deflect the outgoing light to a predetermined angle without amplifying the divergence angle of the incident light. The angle range can be up to plus or minus tens of degrees, so it is very suitable for expanding the scanning field angle. It can only deflect discrete angles and has a slow response speed. Therefore, 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, 2 N Deflects light at discrete angles.

[0407] 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.

[0408] 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-section corresponds to at least one first electrode block 211; each deflection sub-section 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

[0409] The electrodes on both sides of the liquid crystal half-wave plate 214 include a plurality of first electrode segments 211. Two opposing first electrode segments 211 form a first electrode pair 2110. Each deflection sub-segment 2121 corresponds to at least one first electrode pair 2110. Each deflection sub-segment 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.

[0410] 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 .

[0411] 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. The liquid crystal polarization grating 216 can be provided with electrodes or not. These two cases are described below.

[0412] 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 the electrodes on one side or both sides of the liquid crystal half-wave plate 214 into a block structure. The required voltage can be applied to each electrode block respectively, thereby achieving independent adjustment of the deflection angle of each deflection sub-area 2121.

[0413] For the case where one side of the electrode is made into a block structure, see Figure 10a As shown. One side electrode of the liquid crystal half-wave plate 214 includes multiple first electrode blocks 211, and the other side electrode is a first whole electrode 213. Each deflection sub-section 2121 corresponds to at least one first electrode block 211. Each deflection sub-section 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 portions refer to portions that are directly opposite in position, see Figure 10aAs shown in the dashed box, the portion corresponding to the position of at least one first electrode segment 211 refers to the portion of the liquid crystal polarization grating 216 located in the same dashed box as the at least one first electrode segment 211. In this case, each first electrode segment 211 corresponds to one deflection sub-segment 2121. Alternatively, multiple first electrode segments 211 may correspond to one deflection sub-segment 2121. Multiple first electrode segments 211 include two or more first electrode segments 211. The multiple first electrode segments 211 may be arranged in a regular array, such as, but not limited to, a one-dimensional or two-dimensional array, or may be arranged in an irregular array.

[0414] For the case where the electrodes on both sides are made into block structures, see Figure 10b As shown, the electrodes on both sides of the liquid crystal half-wave plate 214 include multiple first electrode blocks 211. Two opposing first electrode blocks form an electrode pair. Each deflection sub-section 2121 corresponds to at least one electrode pair. Each deflection sub-section 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 portions that are directly opposite to each other. Figure 10b The portion shown in the middle dashed box, which corresponds to the position of at least one electrode pair, refers to the portion on the liquid crystal polarization grating 216 located in the same dashed box as the at least one electrode pair. Figure 10b In the embodiment, the electrode blocks corresponding to the two sides of the liquid crystal half-wave plate 214 are directly opposite to each other. However, these corresponding partitioned electrodes may not be strictly opposite to each other, and a slight misalignment between them is also acceptable. In this case, each electrode pair corresponds to a deflection sub-partition 2121, and alternatively, multiple electrode pairs may correspond to one deflection sub-partition 2121. Multiple electrode pairs include cases 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, such as but not limited to a one-dimensional or two-dimensional array, or may be arranged in an irregular array.

[0415] 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 .

[0416] In some optional embodiments, the light deflection unit 210 includes a liquid crystal half-wave plate 214 and a liquid crystal polarization grating 216. The liquid crystal half-wave plate 214 includes electrodes disposed oppositely on two sides and a liquid crystal layer disposed between the electrodes. The liquid crystal polarization grating 216 is an active liquid crystal polarization grating, including electrodes disposed oppositely on two sides and a grating liquid crystal layer 2164 disposed between the electrodes. The control device 600 needs to adjust the voltages applied to the electrodes of the liquid crystal half-wave plate 214 and the electrodes of the active liquid crystal polarization grating 216 to change the deflection angle of the light beam passing through. The deflection sub-segments 2121 of the light deflection unit 210 can be implemented by forming a block structure of one or both electrodes of the liquid crystal half-wave plate 214 and a block structure of one or both electrodes of the liquid crystal polarization grating. A desired voltage can be applied to each electrode block, thereby independently adjusting the deflection angle of each deflection sub-segment 2121. In the light deflection unit 210 , the liquid crystal half-wave plate 214 further includes a first substrate 217 and a second substrate 218 disposed opposite to each other; the liquid crystal polarization grating 216 further includes a third substrate 2161 and a fourth substrate 2162 disposed opposite to each other.

[0417] The case where one side electrode of the liquid crystal polarization grating 216 is configured as a block structure is similar to the case where one side electrode of the liquid crystal half-wave plate 214 is configured as a block structure. The case where both side electrodes of the liquid crystal polarization grating 216 are configured as a block structure is similar to the case where both side electrodes of the liquid crystal half-wave plate 214 are configured as block structures, and will not be further described here. It should be noted that:

[0418] 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 formed into a block structure; Figure 10c As shown, one side of the liquid crystal half-wave plate 214 includes multiple first electrode segments 211, and the other side includes a first block electrode 213. One side of the liquid crystal polarization plate 216 includes multiple second electrode segments 2163, and the other side includes a second block electrode 2165. At least one second electrode segment 2163 on the liquid crystal polarization plate 216 and at least one first electrode segment 211 corresponding to a position on the liquid crystal half-wave plate 214 form a segment group. Each deflection sub-segment 2121 corresponds to at least one segment group, that is, each deflection sub-segment 2121 corresponds to at least one first electrode segment 211 on the liquid crystal half-wave plate 214 and also corresponds to at least one second electrode segment 2163 on the liquid crystal polarization plate 216. Each deflection sub-segment 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the segment group, and a portion on the liquid crystal polarization plate 216 corresponding to the segment group.

[0419] 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. Figure 10d As shown, the electrodes on both sides of the liquid crystal half-wave plate 214 include a plurality of first electrode blocks 211, with two opposing first electrode blocks 211 on the liquid crystal half-wave plate 214 forming a first electrode pair 2110. The electrodes on both sides of the liquid crystal polarization grating 216 include a plurality of second electrode blocks 2163, with two opposing second electrode blocks 2163 on the liquid crystal polarization grating 216 forming a second electrode pair 2160. At least one second electrode pair 2160 on the liquid crystal polarization grating 216 and at least one corresponding first electrode pair 2110 on the liquid crystal half-wave plate 214 form a block group. Each deflection sub-segment 2121 corresponds to at least one block group, that is, each deflection sub-segment 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 216. Each deflection sub-region 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 216 corresponding to the position of the block group.

[0420] In a light deflection unit 210, the electrodes on one side of the liquid crystal polarization plate 216 can be configured as a block structure, and the electrodes on both sides of the liquid crystal half-wave plate 214 can be configured as a block structure. Two opposing 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 plate 216 and at least one first electrode pair corresponding to a position on the liquid crystal half-wave plate 214 form a block group. Each deflection sub-segment 2121 corresponds to at least one block group, that is, each deflection sub-segment 2121 corresponds to at least one first electrode pair on the liquid crystal half-wave plate 214 and also corresponds to at least one second electrode block on the liquid crystal polarization plate 216. Each deflection sub-segment 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the block group position, and a portion on the liquid crystal polarization plate 216 corresponding to the block group position.

[0421] In a light deflection unit 210, the electrodes on both sides of the liquid crystal polarization plate 216 can be configured as a block structure, and the electrodes on one side of the liquid crystal half-wave plate 214 can be configured as a block structure. Two opposing second electrode blocks on the liquid crystal polarization plate 216 form a second electrode pair. At least one second electrode pair on the liquid crystal polarization plate 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-segment 2121 corresponds to at least one block group, that is, each deflection sub-segment 2121 corresponds to at least one first electrode block on the liquid crystal half-wave plate 214 and also to at least one second electrode pair on the liquid crystal polarization plate 216. Each deflection sub-segment 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the block group position, and a portion on the liquid crystal polarization plate 216 corresponding to the block group position.

[0422] 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.

[0423] It should be noted that, in the case where the second optical deflection device 200 includes at least two optical deflection units 210, the respective 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 these multiple deflection sub-partitions 2121 respectively to achieve this.

[0424] From another perspective, the multiple deflection sub-regions 2121 corresponding to the positions of different optical deflection units 210 that can form a deflection optical path can also be understood as a structurally separable deflection sub-region 212. Each deflection sub-region 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-regions 212 are arranged sequentially according to the deflection direction of the light beam at a first deflection angle. In other words, the deflection sub-regions include deflection sub-regions corresponding to the positions of at least one optical deflection unit; the deflection sub-regions 2121 of at least one optical deflection unit 210 included in a deflection sub-region 212 can form a deflection optical path. When a deflection sub-region 212 includes one optical deflection unit 210, the deflection sub-regions 2121 of this optical deflection unit 210 can form a deflection optical path. When a deflection sub-region 212 includes two optical deflection units, the deflection sub-regions 2121 of these two optical deflection units 210 can form a deflection optical path. When a deflection sub-section 212 includes a plurality of light deflection units 210 , the deflection sub-sections 2121 in the plurality of light deflection units can form a deflection light path.

[0425] Optionally, a quarter wave plate may be provided before the first 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.

[0426] The electrodes are, for example but not limited to, ITO electrodes. The shape and arrangement of the electrode blocks are determined by the shape of the light beam to be deflected and the variation in its scanning position on the optical deflection unit 210. The incident light beam is a long, strip-shaped beam with its length along the second direction, scanning along the first direction on the optical deflection unit 210. Correspondingly, the electrode blocks are also long, strip-shaped, with their length along the second direction, and the multiple electrode blocks are also arranged parallel to the first direction. Different electrode blocks are arranged separately, so that voltages can be applied independently to control the arrangement of corresponding portions of liquid crystal molecules within the respective blocks.

[0427] Theoretically, within the same optical deflection device, the liquid crystal half-wave plates 214 belonging to different optical deflection units 210 can also have different ITO electrode structures. For example, the electrode structure of the liquid crystal half-wave plates 214 in some optical deflection units 210 can be partitioned on both sides, while the electrode structure of the liquid crystal half-wave plates 214 in other optical deflection units 210 can be partitioned on one side and unpartitioned on the other side. The liquid crystal polarization gratings 216 belonging to different optical deflection units can also have different ITO electrode structures. For example, the electrode structure of the liquid crystal polarization gratings 216 in some optical deflection units 210 can be partitioned on both sides, while the electrode structure of the liquid crystal polarization gratings 216 in other optical deflection units 210 can be partitioned on one side and unpartitioned on the other side.

[0428] See also Figure 10a 、 10b As shown in Figures 10c and 10d, the liquid crystal half-wave plate 214 may further include a first substrate 217 and a second substrate 218 disposed opposite each other, with electrodes disposed on both sides of the first substrate 217 and the second substrate 218 on their inner surfaces facing each other, the inner surfaces being, for example, planar. The liquid crystal polarization grating 216 may further include a third substrate 2161 and a fourth substrate 2162 disposed opposite each other, with electrodes disposed on both sides of the third substrate 2161 and the fourth substrate 2162 on their inner surfaces facing each other, the inner surfaces being, for example, planar.

[0429] 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 in the second light deflection device 200 are active liquid crystal polarization gratings; the liquid crystal material of the liquid crystal layer may be, for example, but not limited to, one of nematic liquid crystal and blue phase liquid crystal.

[0430] Taking a passive liquid crystal polarization grating as an example, a passive liquid crystal polarization grating does not require the application of voltage to alter the liquid crystal arrangement during operation. By selecting whether or not to apply a voltage to the liquid crystal half-wave plate 214, the polarization state of the light beam passing through the passive liquid crystal polarization grating can be changed, thereby controlling the deflection direction of the light beam passing through the passive liquid crystal polarization grating. The passive liquid crystal polarization grating has a preset deflection angle for the light beam. The left-handed and right-handed polarization components of the incident light beam are deflected into the positive and negative first-order diffraction directions of the liquid crystal polarization grating. These two diffraction directions have equal angles relative to the incident direction, but are deflected in opposite directions. Therefore, by combining optical deflection units with different light beam deflection angles and applying corresponding voltages to the liquid crystal half-wave plate, it is possible to achieve deflection of the light beam at multiple preset angles.

[0431] For each incident light beam emitted by the first light deflection device 100 at a first deflection angle varying along the first direction, as the beam begins scanning, the voltage applied to the scanned deflection sub-area of the second light deflection device 200 is synchronously and sequentially changed, thereby switching the liquid crystal molecular arrangement in the scanned deflection sub-area to the state required for the next beam deflection angle. Thus, each deflection sub-area 212 can switch its liquid crystal arrangement state by utilizing the gaps between the first light deflection device 100 scanning the other deflection sub-areas along the first direction. When the light beam deflected by the first light deflection device 100 completes scanning the last deflection sub-area of the second light deflection device 200 within a deflection cycle, the liquid crystal molecular arrangement in the first deflection sub-area to be scanned in the next deflection cycle has already switched to the state required for the next beam deflection angle. Therefore, the first light deflection device 100 can be immediately controlled to deflect the light beam along the first direction to the first deflection sub-area to be scanned, thereby initiating scanning for 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 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.

[0432] See also Figure 11a The figure shows an example of a structure in which the second optical deflection device 200 uses a passive liquid crystal polarization grating. Each optical deflection unit 210 in the second optical deflection device 200 adopts a binary cascade. The 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 the arrangement, which is 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 N optical deflection units 210 arranged in sequence along the exit direction of the light beam to the passing light beam are ±r, ±2r, ±4r, ..., ±2 respectively. N-1 Correspondingly, the entire second light deflection device 200 including N light deflection units can deflect the passing light beam to the preset deflection angles of ±r, ±3r, ±5r…, ±(2 N-1)·r, it can be seen that the beam deflection angle provided by the second optical deflection device 200 is an odd multiple of the minimum deflection angle r of a single optical deflection unit for the passing light beam, with the maximum value of the odd number being two to the power of N minus one, where N is the number of optical deflection units included in the second optical deflection device 200. The angular interval between the preset deflection angles of adjacent levels is 2r, that is, the multiple preset deflection angles of the passing light beam provided by the second optical deflection device 200 are distributed in an arithmetic progression at preset angular intervals, with a deflection accuracy of 2r for the passing light beam. The angular interval can be considered the angular tolerance of the arithmetic progression. Therefore, the relationship between the second deflection angle range Ψ of the passing light beam and the total number M of different deflection angles that can be provided by the binary cascaded optical deflection units 210 is expressed as:

[0433] Ψ=(2 N -1)·r

[0434] M=2 N

[0435] Here, 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 .

[0436] During use, a voltage can be applied to the liquid crystal half-wave plate 214 in the light deflection unit 210 to select the polarization state of the light beam incident on the passive liquid crystal polarization grating 216 in the light deflection unit 210, thereby correspondingly controlling the direction of diffraction of the light beam when it passes through the passive liquid crystal polarization grating 216. For example, if a light beam is deflected in the direction of positive first-order diffraction after passing through the liquid crystal half-wave plate 214 with a saturated voltage 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 without a voltage applied and then passing through the passive liquid crystal polarization grating 216. Since the polarization state of the light beam is also changed when it is 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.

[0437] Figure 11bThis diagram shows the relationship between the voltage control of the binary cascaded optical deflection unit 210 and the deflection angle of the one-dimensional deflection of the passing light beam. The shaded areas in the figure indicate that a saturation voltage is applied to the corresponding liquid crystal half-wave plate 214. In this case, the liquid crystal half-wave plate 214 does not change the polarization state of the passing light beam. The white areas indicate 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 changes the polarization state of the passing light beam. Because the liquid crystal polarization gratings are all passive, no voltage can be applied to any of the passive liquid crystal polarization gratings 216. They deflect the passing light beam by a preset angle in the direction corresponding to the positive or negative first-order diffraction according to its polarization state. Figure 11b The second optical deflection device is exemplarily shown as comprising four optical deflection units in a binary cascade arrangement. Each optical deflection unit comprises a liquid crystal half-wave plate and a passive liquid crystal polarization grating. In order of the optical beam's exit direction, the first optical deflection unit comprises liquid crystal half-wave plate I and passive liquid crystal polarization grating I; the second optical deflection unit comprises liquid crystal half-wave plate II and passive liquid crystal polarization grating II; the third optical deflection unit comprises liquid crystal half-wave plate III and passive liquid crystal polarization grating III; and the fourth optical deflection unit comprises liquid crystal half-wave plate IV and passive liquid crystal polarization grating IV. Furthermore, the passive liquid crystal polarization gratings I-IV have the same grating vector orientation. The deflection angles of the passive liquid crystal polarization gratings I-IV relative to the optical beam increase in order by a natural number, with the natural number being the number of the optical deflection unit minus one, corresponding to r, 2r, 4r, and 8r. In practical applications, the deflection angle of each liquid crystal polarization grating relative to the optical beam can be selected as needed.

[0438] See also Figure 11a and Figure 11bAs shown, a reference frame is established with a horizontally incident light beam at 0 degrees, with leftward deflection as a positive angle and rightward deflection as a negative angle. If the polarization state of the light beam upon incident on the second light deflection device 200 causes the passive liquid crystal polarization plate to deflect the light beam toward the positive first-order diffraction direction, and if a deflection angle of +r is desired after the light beam passes through the entire second light deflection device, the voltage applied to the liquid crystal half-wave plate I must be turned off, causing the light beam passing through the liquid crystal half-wave plate I to first convert its polarization state. This allows the passive liquid crystal polarization plate I to deflect the light beam by -r and simultaneously return its polarization state to its incident state. Since the passive liquid crystal polarization plate II and the passive liquid crystal polarization plate III will then need to further deflect the light beam toward -2r and -4r, respectively, the voltages applied to the liquid crystal half-wave plate II and the liquid crystal half-wave plate III must be turned off accordingly to convert the polarization state of the light beam before entering the corresponding passive liquid crystal polarization plate II and the passive liquid crystal polarization plate 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 III. In this way, 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 formed by Figure 11b The voltage application method shown deflects the passing light beam to other preset deflection angles, such as angles of 3r, 5r, 7r, 9r, 11r, 13r, 15r, -r, -3r, -5r, -7r, -9r, -11r, -13r, and -15r in the figure. By varying the voltage applied to the liquid crystal half-wave plates I-IV, the polarization state of the light beam before entering the corresponding passive liquid crystal polarization grating plates I-IV is adjusted. The four light deflection units 210 cooperate to achieve 16 different deflection angles. It will be appreciated that achieving a different number of deflection angles can be achieved by providing a different number of light deflection units 210.

[0439] Figure 11c Schematic diagram of 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. Figure 11b The difference is that Figure 11b The four deflection units deflect the light beam in the same direction, such as horizontally or vertically. Figure 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 work together to achieve two deflection angles in the vertical direction and eight deflection angles in the horizontal direction. For example, Figure 11cThe angles shown in 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), (p, -h).

[0440] If an active liquid crystal polarization grating is used, the following differences apply: A passive liquid crystal polarization grating does not require voltage during operation; instead, it deflects the light beam by applying a corresponding voltage to the liquid crystal half-wave plate, resulting in a fast response and a simple driver. An active liquid crystal polarization grating requires voltage application for different deflection angles during operation; however, the voltages applied to both the liquid crystal half-wave plate and the active liquid crystal polarization grating must be adjusted separately for different deflection angles. When an active liquid crystal polarization grating is used, the voltages applied to both the liquid crystal half-wave plate and the active liquid crystal polarization grating in the light deflection unit 210 of the second light deflection device can be varied. By varying the applied voltages, different deflection angles can be achieved, which will not be further described here.

[0441] In some optional embodiments, in the second optical deflection device 200, the time required for adjusting the second deflection angle of the incident light beam by adjusting the deflection zones is no longer than the time interval between two adjacent deflection cycles when the deflection zones are scanned by the incident light beam. To ensure that each deflection zone has sufficient time to adjust its deflection angle, the number of deflection zones can be appropriately set within the duration of the deflection cycle. This is because if the number of deflection zones is too small, it cannot be guaranteed that the time interval between two adjacent deflection cycles when each deflection zone is scanned by the incident light beam is sufficient to complete the deflection angle adjustment. Therefore, the number of deflection zones is determined based on 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 having 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 a single deflection angle adjustment. In other words, the number of deflection zones can be set based on the number of deflection angles of the second optical deflection device 200, the required frame rate, and the time required for the second optical deflection device to complete a deflection angle adjustment. This ensures that, while meeting the required frame rate, the deflection zones can complete deflection angle adjustment within the interval between two scans. Specifically, the number D of deflection zones 212 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 200, F is the frame rate at which the second optical deflection device 200 completes a cycle of M deflection angles, and T is the time required for the second optical deflection device 200 to complete a deflection angle adjustment. Setting the number of deflection zones according to this formula is a preferred approach, as it allows each deflection zone to complete angle adjustment without waiting, allowing for the use of scanning intervals. Even setting a smaller number can still reduce waiting time to a certain extent.

[0442] The response speed of the liquid crystal half-wave plate 214 is on the order of several milliseconds. The system is inactive while adjusting the liquid crystal switching state. To meet the 10Hz frame rate requirement for optical scanning, a single pass through all scanning angles must be completed within 100ms. Therefore, to ensure system scanning efficiency, 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 liquid crystal polarization grating is divided into blocks. During light beam scanning, the light beam is incident on one electrode block, and the remaining electrode blocks not incident on the light beam can be adjusted to change the phase delay.

[0443] Take the example of the first light deflection device 100 deflecting the emitted light beam in the vertical direction. 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. Figure 12 、 Figure 13 、 Figure 14As shown, at the beginning of a frame (100ms duration), the light beam enters the first deflection sub-area, and the vertical beam width is designed to be the width of one deflection sub-area. The first optical deflection device 100 quasi-continuously deflects the light beam downward, and the light beam begins to enter the second deflection sub-area. At this point, the first and second deflection sub-areas are in a "scanning" state, and the state of the liquid crystal molecules therein cannot be adjusted. The remaining K-2 layers are in a "non-scanning" state. When the light beam leaves the first deflection sub-area and begins to enter the third deflection sub-area, the first deflection sub-area enters a "non-scanning" state, while the second and third deflection sub-areas enter a "scanning" state. According to the above rules, when the light beam enters the Dth deflection sub-area, a deflection cycle is completed. At this point, the first optical deflection device 100 deflects the light beam into the first deflection sub-area, and the second deflection cycle begins. Multiple deflection cycles are required within a frame, and during each deflection cycle, the second optical deflection device 200 deflects the light to one of multiple discrete angles.

[0444] See also Figure 12 、 Figure 13 、 Figure 14 As shown, in some embodiments, the light deflection unit 210 is divided into 1-D parallel 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 block, 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 the incident light beam scanning 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 block, 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, and the incident light beam can immediately and seamlessly start scanning the next second deflection angle again from the 1st deflection partition.

[0445] 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.

[0446] The above description uses the example of a beam scanning each deflection sub-area from top to bottom within a deflection cycle. In the next deflection cycle, the beam scans each deflection sub-area sequentially from top to bottom. In practice, scanning does not necessarily follow this order; the scanning order can be adjusted randomly, for example, rather than sequentially from top to bottom. Furthermore, within a deflection cycle, the second deflection angle of each beam can be the same or different, as long as the entire field of view is covered.

[0447] In the above-mentioned second optical deflection device 200, the optical deflection unit is divided into D deflection sub-partitions along the first direction. 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. Accordingly, 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.

[0448] In addition to LCPG, the second optical deflection device 200 may also utilize other suitable devices capable of achieving coarse light beam deflection. Any optical deflection device that is divided into multiple deflection zones 212 and each of which can independently adjust the light beam deflection angle is consistent with the concepts of the present invention. The second optical deflection device 200 is typically relatively thin, so when an incident light beam enters the optical deflection device, the beam path is not affected by the thickness of the optical deflection device and can be approximately straight.

[0449] In some optional embodiments, the second optical deflection device 200 further includes a temperature regulator 240 configured to adjust the time it takes for the second optical deflection device to adjust its deflection angle by changing the temperature of the second optical deflection device 200. To ensure that the liquid crystal molecules within the liquid crystal polarization grating in the second optical deflection device can function properly, it is necessary to control the temperature of the second optical 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 optical deflection device 200 within a preset temperature range. Furthermore, at different temperatures, the speed at which the liquid crystal molecules adjust their states varies, resulting in different times for each deflection partition to adjust its deflection angle. Therefore, the time it takes for each deflection partition to adjust its deflection angle can be changed by changing the temperature of the second optical deflection device 200.

[0450] The second optical deflection device 200, which adopts a partitioned structure, can synchronously refresh the arrangement of the liquid crystal molecules in the scanned deflection partition to the state required for the next second deflection angle by applying a change in voltage during the process of the incident position changing due to the change in the first deflection angle of the incident light beam, so that the switching of the light beam deflection angle can be seamless and does not require waiting. With existing LCPG modules, 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 correspondingly change the voltage applied to the ITO electrode of the liquid crystal half-wave plate. This process requires waiting for the liquid crystal molecules to change their arrangement state, which takes a long time. Therefore, during the above-mentioned switching of the deflection angle, the entire system of the existing LCPG module can only wait and cannot perform scanning and detection.

[0451] In some optional embodiments, the incident light beam may be in the form of a strip beam, and the second light deflection device 200 is configured to: when the incident light beam is in the form of a strip beam, deflect the incident light beams at multiple different first deflection angles by the same second deflection angle to scan a corresponding scanning subarea of the field of view; and deflect the light beams at each first deflection angle of the multiple light beams at different first deflection angles by multiple different second deflection angles to scan multiple scanning subareas corresponding to the multiple different second deflection angles. The scanning subareas are rectangular, and the length of the light beam after deflection by the second deflection angle is equal to the length of the scanning subarea in one direction.

[0452] It is understood that in some embodiments, when completing a scan of the entire field of view, the angles and order of the light beams at the first deflection angle and the second deflection angle can be configured to first complete the scan of one scan area, then proceed to scan the next scan area, and so on, until all scan areas are scanned. That is, within a deflection cycle, multiple incident light beams at different first deflection angles can be deflected by the same second deflection angle to complete the scan of a corresponding scan subarea within the field of view; different deflection cycles deflect the incident light beams at the multiple different first deflection angles at different second deflection angles, thereby concentrating on completing the scan of a corresponding scan subarea within a deflection cycle; after completing one scan subarea, the next deflection cycle scans the next scan subarea; thus, multiple deflection cycles can complete the scan of multiple different scan subareas.

[0453] See also Figure 2 As shown, the entire field of view can be divided into multiple scanning areas. Figure 2 In the figure, 16 scanning zones are used as an example, corresponding to the 16 grids in the figure. Different deflection zones of the second light deflection device 200 deflect the received strip incident light into different second deflection angles so that it can illuminate different scanning zones. One second deflection angle corresponds to one scanning zone. After multiple incident light beams of the first deflection angle are deflected into the second deflection angle, one scanning zone can be fully covered. 16 second deflection angles can correspond to 16 scanning zones. Figure 2 As shown, by deflecting 2 second deflection angles in the first direction and 8 second deflection angles in the second direction, the Figure 2 The scanning of the 16 scanning partitions shown in the figure corresponds to a second deflection angle for each scanning partition, that is, after the multiple different first deflection angles deflected by the first optical deflection device 100 are deflected to the same second deflection angle by the second optical deflection device 200, they can cover a scanning partition. Wherein, 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 can be deflected to 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 can be deflected to the second second deflection angle to complete the scanning of the scanning partition corresponding to the second square of the first row; ...; in the fourth deflection cycle, the multiple light beams with the first deflection angles can be 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.

[0454] In some other embodiments, the second optical deflection device 200 deflects incident light beams at multiple different first deflection angles by one of multiple different second deflection angles within a deflection cycle, respectively, to scan portions of corresponding scanning subareas. Within a deflection cycle, the incident light beams at multiple different first deflection angles are deflected by the same or different second deflection angles, and the incident light beams at each first deflection angle are deflected by different second deflection angles within different deflection cycles. Within a deflection cycle, each incident light beam at multiple different first deflection angles is randomly deflected by one of multiple different second deflection angles, such that the second deflection angles of all incident light beams at the first deflection angles within a deflection cycle are the same, partially the same, partially different, or completely different from each other. Optionally, within a deflection cycle, at least two incident light beams at multiple different first deflection angles are deflected by different second deflection angles, such that the second deflection angles of all incident light beams at the first deflection angles within a deflection cycle are partially the same, partially different, or completely different from each other.

[0455] For example, within a deflection cycle, a deflected light beam incident at different first deflection angles can be deflected to two or more different second deflection angles. In this case, within a deflection cycle, scanning is no longer concentrated on a single scanning subarea, but rather, scanning is performed in a skipped manner, corresponding to different positions along the first deflection angle within two or more different scanning subareas. This allows for the completion of scanning of all scanning subareas over multiple deflection cycles. For example, in this embodiment, within a deflection cycle, the positions scanned by the light beam formed after deflection at the second deflection angle corresponding to scanning subareas corresponding to different second deflection angles are relatively far apart, thereby reducing crosstalk between adjacent scans.

[0456] 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. Within a 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, within the first deflection cycle, the second optical deflection device 200 deflects the light beam of the first first deflection angle by the first second deflection angle to scan a small strip area in the first square of the first row; deflects the light beam of the second first deflection angle by the second second deflection angle to scan a small strip area in the second square of the first row; .... Within the second deflection cycle, the second optical deflection device 200 deflects the light beam of the first first deflection angle by the first second deflection angle to scan a small strip area in the second square of the first row; deflects the light beam of the second first deflection angle by the second second deflection angle to scan a small strip area in the third square of the first row; .... Similarly, the scanning area corresponding to each square is cross-scanned, and after multiple deflection cycles, all scanning subareas corresponding to all squares are scanned. This configuration allows the two scanning areas scanned within the field of view during two adjacent deflection cycles to be farther apart. The receiving module's photosensitive pixels used to sense these two corresponding scanning areas during these two adjacent scanning periods are also spaced farther apart, reducing crosstalk between these consecutively operating photosensitive pixels.

[0457] 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 angles are 16, 8 in the horizontal direction and 2 in the vertical direction, and 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 angles are 16, 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.

[0458] The scanning partition is rectangular, and the length of the strip beam after deflection 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. This allows the light beam deflected by the second deflection angle to cover a wider field of view than the block-shaped scanning light at the same total power. Therefore, the second optical deflection device 200 can cover a larger overall field of view by deflecting a smaller number of different angles. This results in fewer layers of the second optical deflection device 200 (that is, the number of optical deflection units 210), lower costs, and faster response speeds.

[0459] The above-mentioned transmitting module can be applied in the field of depth sensing technology, for example, but not limited to, in laser radar systems using all-solid-state scanning, as a light deflection structure to achieve full field of view coverage scanning, thereby increasing detection range and increasing transmission power per unit field of view angle. It can also be used in fields such as high-speed photography, optical engineering, space optical communications, non-destructive testing, optical sensing technology, optical multi-mode guidance technology, magneto-optical recording technology, magneto-optical imaging technology, laser display technology, and precision optical instruments. 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 performs fine deflection of the light beam, while 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. Because 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 full coverage of the field of view. The second light deflection device 200 may be a liquid crystal light deflection device.

[0460] 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 5 As shown, it includes a first control unit 110 and a second control unit 230;

[0461] 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 cause the incident light beam of each first deflection angle to be 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.

[0462] The second control unit 230 is configured to control the multiple deflection sub-zones 212 to receive the incident light beam in a time-sharing manner and deflect the incident light beam to a desired second deflection angle. Furthermore, the second control unit 230 is configured to control the deflection sub-zones 212 to pre-adjust their deflection angles relative to the incident light beam before being scanned by the incident light beam. The second control unit 230 is configured to adjust the deflection angle of at least one deflection sub-zone 212 relative to the incident light beam to the desired second deflection angle for the next deflection cycle after the incident light beam scan completes in the current deflection cycle and before the incident light beam scan begins in the next deflection cycle. The second control unit 230 may be provided separately or integrated with the second optical deflection device.

[0463] In some optional embodiments, the apparatus further includes 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.

[0464] The aforementioned partitioned light deflection unit 210 can synchronously refresh the arrangement of the liquid crystal molecules in the scanned deflection partitions to the state required for the next second deflection angle by applying a voltage change during a change in the incident position caused by a change in the first deflection angle of the incident light beam, thereby enabling seamless switching of the light beam deflection angle without waiting. In existing LCPG modules, 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 correspondingly change the voltage applied to the ITO electrode of the liquid crystal half-wave plate. This process requires waiting for the liquid crystal molecules to change their arrangement state, which is time-consuming. Therefore, during the aforementioned deflection angle switching process, the entire system of the existing LCPG module can only wait and cannot perform scanning and detection.

[0465] Example 3

[0466] The transmission module provided in the third embodiment of the present invention is shown in FIG. Figure 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 partitioned structure. At this time, the light beam deflected by the first optical deflection device 100 is expanded by the expansion device 500 and projected onto the corresponding position of the second optical deflection device. Since the second optical deflection device is not partitioned, within one deflection cycle, the first optical deflection device deflects multiple light beams with first deflection angles in the first direction, and the 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, it may be necessary to wait for a certain time to complete the adjustment of the deflection angle before the next deflection cycle begins.

[0467] Optionally, in this third embodiment, to reduce the waiting time for adjusting the deflection angle, the temperature of the second light deflection device can be adjusted to speed up the switching time of the liquid crystal molecule arrangement state. Alternatively, a blue phase liquid crystal with a faster corresponding speed can be used to speed up the angle switching time.

[0468] Example 4

[0469] The transmission module provided in the fourth embodiment of the present invention is shown in FIG. Figure 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.

[0470] Placing the polarization expander 500 behind the second optical deflection device 200 allows the second optical deflection device 200 to be close to the first optical deflection device 100, which is beneficial for shortening the optical path length. At the same time, it reduces the size of the light beam reaching the second optical deflection device 200, making the size of the second optical deflection device smaller, and is also beneficial for miniaturization of the entire module.

[0471] Example 5

[0472] The structure diagram of the transmitting module provided in the fifth embodiment of the present invention is shown in FIG. Figure 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.

[0473] Placing the polarization expander 500 behind the second optical deflection device 200 allows the second optical deflection device 200 to be close to the first optical deflection device 100, which is beneficial for shortening the optical path length. At the same time, it reduces the size of the light beam reaching the second optical deflection device 200, making the size of the second optical deflection device smaller, and is also beneficial for miniaturization of the entire module.

[0474] In the emission module provided by the embodiment of the present invention, the light beam emitted by the light source is a strip-shaped light beam, and an 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, while 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 of light in the far field that is narrow in the direction of light deflection and wide perpendicular to the direction of light deflection. This is more in line with the luminescence characteristics of the current mainstream high-power semiconductor laser source: the beam parameter product (BPP) of a high-power laser light source spliced together 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 being collimated by the lens and incident on the AOD, 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.

[0475] On this basis, LCPG is subsequently used as a coarse scanning device in the AOD, and the light beam emitted from the AOD is deflected at a larger angle in a time-sharing manner. For each angle to which the LCPG is deflected, the AOD performs a fine scan 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 the AOD is perpendicular to the light deflection direction of the AOD, so that compared with the block-shaped scanning light, at the same total power, the field of view angle covered by AOD scanning is larger. Therefore, the LCPG only needs to deflect a smaller number of different angles to cover a larger overall field of view. This requires fewer LCPG layers, lower costs, and faster response speeds.

[0476] The present invention also provides a laser radar system, the structure of which is as follows: Figure 18 As shown, it includes a receiving module 2 and the above-mentioned transmitting module 1. The receiving module 2 is configured to sense light signals from the field of view and obtain three-dimensional information of the field of view by processing and analyzing the light signals.

[0477] An embodiment of the present invention also provides an electronic device, comprising the above-mentioned laser radar system.

[0478] The present invention also provides a laser radar scanning method, the process of which is as follows: Figure 19 As shown, the following steps are included:

[0479] 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 first-level light deflection. The length of the light beam along the first direction is shorter than the length along the second direction.

[0480] 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 within a deflection period.

[0481] 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.

[0482] In a deflection cycle, the incident angles of the light beams with multiple different first deflection angles vary from large to small, or from small to large, or vary according to a preset random rule in each deflection direction.

[0483] 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.

[0484] In this step, the second light deflecting device may be controlled by the control device to deflect the light beam.

[0485] In some embodiments, the light beam emitted by the light source is a strip 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 beam with an aspect ratio of 20:1 to 80:1.

[0486] Optionally, the aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on 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 on the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 25:1.

[0487] In some embodiments, the above 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.

[0488] Among them, collimating the light beam includes: collimating the light beam with an aspect ratio of A in the first direction with a first collimation index, and collimating it in the 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, and project a light beam with an aspect ratio of C, and C>B.

[0489] In some embodiments, the collimating device collimates the light beam, including:

[0490] 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

[0491] A spherical lens collimates the incident light beam in a first direction and a second direction simultaneously; or

[0492] 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 simultaneously.

[0493] In some embodiments, the following relationships are satisfied between 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 that collimates the light beam along the first direction: θ2=V1 / F2, θ2V2=θ1V1.

[0494] The following relationship is satisfied between the luminous length H1 of the light source in the second direction, the divergence angle Θ1 of the light 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, Θ2H2 = Θ1H1.

[0495] 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.

[0496] 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.

[0497] In some embodiments, the deflection angle range of the plurality of first deflection angles deflected along the first direction during the first-level light deflection is greater than or equal to the angular interval between two adjacent second deflection angles along the first direction during the second-level light deflection.

[0498] In some embodiments, the deflection accuracy of the light beam at the first deflection angle is higher than the deflection accuracy of the light beam at the second deflection angle.

[0499] 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 range, wherein a length of the field of view range in the first direction is smaller than a length in the second direction.

[0500] In some embodiments, the divergence angle of the collimated light beam after collimation in the first direction is less than 1 / 10 of the divergence angle of the collimated light beam after collimation in the second direction.

[0501] In some embodiments, the method further includes: a polarization expander amplifying 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. This process may include: at least one polarization expander lens amplifying 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:

[0502] When the polarization expanding device includes two groups of cylindrical lenses, the first polarization expanding 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 expanding lens group includes a first polarization expanding cylindrical lens and a second polarization expanding cylindrical lens, 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 polarization expanding 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 expanding lens group includes a third polarization expanding cylindrical lens and a fourth polarization expanding cylindrical lens, 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;

[0503] When the polarization expanding device includes two spherical lenses, the first polarization expanding spherical lens and the second polarization expanding 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 expanding spherical lens to the focal length of the second polarization expanding spherical lens.

[0504] In some embodiments, the above method also includes: magnifying 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 multiple is the same as the deflection angle magnification multiple of the deflected light beam in the deflection direction.

[0505] 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 completed and before the next deflection cycle is started.

[0506] When the first optical deflection device 100 deflects the light beams at multiple different first deflection angles in a time-sharing manner, the multiple deflection sub-areas 212 are controlled to receive the light beams at multiple different first deflection angles in a time-sharing manner. The control of at least one deflection sub-area that is not currently being scanned to adjust the light beam deflection angle to a second deflection angle required for the next deflection period after the light beam scanning ends in the current deflection period and before the light beam scanning begins in the next deflection period includes: after determining that a deflection sub-area has completed light beam deflection in the current deflection period and is in a non-scanning state, controlling the deflection sub-area to adjust its light beam deflection angle to the second deflection angle required for the next deflection period before entering a scanning state in the next deflection period.

[0507] Optionally, if a deflection partition is the 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 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, the deflection partition is determined to be in a non-scanning state.

[0508] 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.

[0509] In some embodiments, the multiple second deflection angles used to deflect the light beam within a deflection cycle are all the same, or all different, or some are the same and some are different. A deflection sub-area can sequentially receive one, two, or more incident light beams with different first deflection angles within a deflection cycle. The multiple deflection sub-areas are configured such that the multiple second deflection angles used to deflect the light beam within a deflection cycle are all the same, or all different, or some are the same and some are different.

[0510] 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.

[0511] In some embodiments, the voltage applied to the electrodes of each deflection sub-area is controlled to adjust the refractive index of the medium within the deflection sub-area with respect to the light beam, thereby adjusting the deflection angle of the light beam by the deflection sub-area. When the second light deflection device utilizes a liquid crystal polarization grating, the voltage applied to the electrodes of each deflection sub-area is controlled to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating, thereby changing the second deflection angle of the light beam by the deflection sub-area.

[0512] Optionally, the second optical deflection device includes at least one optical deflection unit, and the optical deflection unit includes multiple 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 the at least one deflection sub-partition is changed by changing the voltages on the electrodes at both ends of the at least one deflection sub-partition, so as to achieve the second deflection angle of the light beam by the corresponding deflection sub-partition.

[0513] 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 and the second direction are perpendicular.

[0514] In some embodiments, the time required for adjusting the second deflection angle of the light beam by the deflection partition is no longer than the time interval between two adjacent scans of the deflection partition by the light beam.

[0515] In some embodiments, the number of deflection zones is determined based on 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 having 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 zones 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 completes one round of M deflection angles, and T is the time required for the second optical deflection device to complete one deflection angle adjustment.

[0516] In some embodiments, the following control processes are performed in parallel: controlling the currently scanned deflection subarea in the second light deflection device to deflect the light beam, and controlling at least one currently unscanned deflection subarea to adjust its deflection angle of the light beam.

[0517] 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, thereby completing the scanning of a corresponding scanning partition of 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, thereby completing 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 one direction of the scanning partition.

[0518] Optionally, within one deflection cycle, multiple light beams with different first deflection angles are deflected to the same second deflection angle to complete scanning of a corresponding scanning subarea within the field of view; each deflection cycle corresponds to a different second deflection angle; and different deflection cycles deflect the light beams with different first deflection angles at different second deflection angles.

[0519] Optionally, within one deflection cycle, multiple light beams with different first deflection angles are respectively deflected to one of multiple different second deflection angles to scan partial areas in corresponding scanning partitions; wherein, within one deflection cycle, multiple light beams with different first deflection angles are deflected to the same or different second deflection angles; and within different deflection cycles, each light beam with a first deflection angle is deflected to a different second deflection angle.

[0520] In some embodiments, the above 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.

[0521] The above-mentioned method of the embodiment of the present utility model, wherein the relevant contents have been described in detail in the relevant parts of the transmitting module and the lidar system, will not be repeated here.

[0522] In the above description of the embodiments of the present invention, when multiple is involved, it should be understood to include two or more.

[0523] Unless otherwise specifically stated, terms such as process, calculate, compute, determine, display, and the like may refer to the actions and / or processes of one or more processing or computing systems, or similar devices, that manipulate 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 the 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 referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0524] It should be understood that the specific order or hierarchy of steps in the disclosed processes 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 the present disclosure. The accompanying method claims present elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0525] In the foregoing 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 embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the invention comprises less than all the features of any individual disclosed embodiment. 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.

[0526] 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 may be implemented as electronic hardware, computer software, or a combination thereof. In order to clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described around their functions. Whether such functions are implemented as hardware or software depends on the specific application and the design constraints imposed on the entire system. A skilled person may implement the described functions in an adaptable manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection of this disclosure.

[0527] The steps of the methods or algorithms described in conjunction with the embodiments herein may be directly embodied as hardware, software modules executed by a processor, or a combination thereof. The software module may be located in a RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, register, hard disk, removable disk, 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 write information to the storage medium. Of course, the storage medium may also be an integral part of the processor. The processor and storage medium may be located in an ASIC. The ASIC may be located in a user terminal. Of course, the processor and storage medium may also be present in a user terminal as discrete components.

[0528] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. These software codes can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or external to the processor. In the latter case, it is communicatively coupled to the processor via various means, which are well known in the art.

[0529] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purposes of describing the above embodiments, but one of ordinary skill in the art will recognize that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of the appended claims. Furthermore, to the extent the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including," as explained in terms of "including," used as a transitional word in the claims. Furthermore, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or."

Claims

1. A transmitting module, characterized in that: comprising a light source, a first light deflection device and a second light deflection device; a light source 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; a first light deflecting device configured to deflect the light beam along a first direction by a plurality of first deflection angles; a second light deflecting device configured to deflect the light beam deflected by the first light deflecting device by a plurality of second deflection angles in a first direction and a second direction to project a scanning light beam; wherein the length of the scanning light beam in the first direction is smaller than the length in the second direction; The length of the scanning light beam in the second direction is not less than the length of the light beam emitted by the light source in the second direction.

2. The transmitting module according to claim 1, wherein: The light source includes a plurality of light-emitting units spliced together to emit a light beam with a required aspect ratio; The light emitting unit is at least one of an edge emitting laser (EEL), a vertical cavity surface emitting laser (VCSEL), a light emitting diode (LED), a laser diode (LD), a semiconductor laser, and a fiber laser.

3. The transmitting module according to claim 1, wherein: The light beam emitted by the light source is a strip-shaped 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; the scanning light beam is a strip-shaped light beam with an aspect ratio of 20:1 to 80:

1.

4. The transmitting module according to claim 3, wherein: The aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; the aspect ratio of the scanning light beam is 75:1; or The aspect ratio of the light beam emitted by the light source is 50:1; the aspect ratio of the light beam incident on the first light deflection device is 5:2; and the aspect ratio of the scanning light beam is 25:

1.

5. The transmitting module according to claim 1, wherein: It also includes a collimating device configured to collimate the light beam before the light beam enters the first light deflection device; wherein the collimation degree of the collimated light beam along the first direction is higher than the collimation degree along the second direction; the first direction is perpendicular to the second direction.

6. The transmitting module according to claim 5, wherein: The collimating device includes at least one collimating lens, and the light source is arranged on the focal plane of the collimating lens; when the collimating device includes at least two collimating lenses, the focal planes of the at least two collimating lenses coincide with each other.

7. The transmitting module according to claim 5, wherein: The collimating device includes a first cylindrical lens and a second cylindrical lens, 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; or, The collimating device includes a spherical lens configured to collimate the light beam along a first direction and a second direction; or, The collimating device 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 simultaneously.

8. The transmitting module according to claim 5, wherein: The collimating device is configured to collimate a light beam with an aspect ratio A into a light beam with an aspect ratio B, and A>B; The first light deflection device and the second light deflection device are configured to deflect the light beam with an aspect ratio of B and project a light beam with an aspect ratio of C, where C>B.

9. The transmitting module according to claim 5, wherein: The following relationships are satisfied among the light emitting width V1 of the light source in the first direction, the divergence angle θ1 of the light emitting from 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, θ2V2=θ1V1; The following relationship is satisfied between the luminous length H1 of the light source in the second direction, the divergence angle Θ1 of the light source 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, Θ2H2=Θ1H1.

10. The transmitting module according to claim 5, wherein: 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; The first direction is a vertical direction, and the second direction is a horizontal direction; or the first direction is a horizontal direction, and the second direction is a vertical direction.

11. The transmitting module according to claim 1, wherein: It also includes a deflection expansion device 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.

12. The transmitting module according to claim 11, wherein: The deflection expanding device is arranged 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 by a preset multiple before the light beam is incident on the second light deflection device; or The deflection expansion device is arranged on the light-emitting side of the second light deflection device, and is configured to amplify the deflection angle of the light beam deflected by the second light deflection device by a preset multiple.

13. The transmitting module according to claim 11, wherein: The divergence angle of the strip light beam formed after deflection expansion by the deflection expansion device along the second direction is greater than or equal to the angular interval between two adjacent second deflection angles of the second light deflection device along the second direction.

14. The transmitting module according to claim 11, wherein: The polarization expansion device includes at least one polarization expansion lens, which is a single lens or a combination of two or more lenses; the polarization expansion lens includes at least one or any combination of a cylindrical lens, a spherical lens, a super lens and a Fresnel lens; The at least one polarization expander lens is configured to magnify a 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 by a preset multiple.

15. The transmitting module according to claim 14, wherein: The focal length of the polarization expanding lens is set according to the magnification of the deflection angle. When the polarization expanding device includes two polarization expanding lenses, the focus of one side of one polarization expanding lens coincides with the focus of one side of the other polarization expanding lens, and the magnification is the ratio of the focal lengths of the two polarization expanding lenses.

16. The transmitting module according to claim 15, wherein: The distance between the first light deflection device and the first polarization expanding lens in the polarization expanding device 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.

17. The transmitting module according to claim 1, wherein: The first light deflection device is configured to deflect the light beam in the first direction by a deflection angle range that is greater than or equal to an angular interval between two adjacent second deflection angles of the second light deflection device in the first direction; The first light deflection device is configured to deflect the incident light beam at a plurality of different first deflection angles, wherein an angular interval between two adjacent first deflection angles is less than or equal to a divergence angle of the incident light beam along the deflection direction.

18. The transmitting module according to claim 1, wherein: The first light deflection device is an acousto-optic deflector, and the second light deflection device is a liquid crystal polarization grating, wherein the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating plate included in the liquid crystal polarization grating is nematic liquid crystal or blue phase liquid crystal; The deflection accuracy of the first light deflection device on the light beam is higher than the deflection accuracy of the second light deflection device on the light beam; The deflection speed of the light beam by the first light deflection device is higher than the deflection speed of the light beam by the second light deflection device.

19. The transmitting module according to any one of claims 1 to 18, wherein: The second optical deflection device includes at least two optical deflection unit groups, each optical deflection unit group includes at least one optical deflection unit, wherein at least one optical deflection unit group is configured to deflect the light beam in a first direction, and at least one optical deflection unit group is configured to deflect the light beam in a second direction.

20. The transmitting module according to claim 19, wherein: The second light deflection device includes a plurality of deflection sub-areas, and each deflection sub-area can independently adjust the deflection angle of the incident light beam; The plurality of deflection subareas are configured to deflect the light beam to a second deflection angle required by the deflection subarea currently being scanned; The transmitting module further includes a control device for controlling the 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.

21. The transmitting module according to claim 20, wherein: The arrangement direction of the multiple deflection subareas is consistent with the scanning direction of the light beams with multiple different first deflection angles.

22. The transmitting module according to claim 21, wherein: The plurality of deflecting sections included in the second light deflecting device are arranged along a first direction.

23. The transmitting module according to claim 20, wherein: The plurality of deflection sub-areas are configured such that: the number of light beams received by each deflection sub-area is the same, different, or partially the same and partially different; accordingly, the widths of the plurality of deflection sub-areas are the same, different, or partially the same and partially different; The 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 beams of multiple different first deflection angles. The width of each deflection partition is determined according to the number of received beams and the width of the beams.

24. The transmitting module according to claim 20, wherein: When the second light deflection device has a non-partitioned structure, the control device is used to control the voltage applied to the electrodes of the second light deflection device to adjust the refractive index of the medium in the second light deflection device with respect to the incident light beam, thereby adjusting the deflection angle of the incident light beam by the second light deflection device; When the second light deflection device has a partitioned structure, the control device is used to control the voltage applied to the electrodes of each deflection partition 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.

25. The transmitting module according to claim 20, wherein: When the second light deflection device adopts a liquid crystal polarization grating and has a non-partitioned structure, the control device 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 light beam by the second light deflection device; When the second light deflection device adopts a liquid crystal polarization grating and has a partitioned structure, the control device is used to control the voltage applied to the electrodes of each deflection partition to adjust the arrangement direction of the liquid crystal molecules in the liquid crystal polarization grating to change the second deflection angle of the deflection partition to the light beam.

26. The transmitting module according to claim 20, wherein: When the second optical deflection device includes at least two optical deflection units, the optical deflection unit includes multiple deflection sub-partitions; the deflection sub-partitions include deflection sub-partitions corresponding to the positions in the at least one optical deflection unit; the deflection sub-partitions in at least one optical deflection unit included in a deflection sub-partition can form a deflection optical path.

27. The transmitting module according to claim 26, wherein: When the second optical deflection device includes two optical deflection units, the deflection partition includes two deflection sub-partitions corresponding to the positions on the two optical deflection units; when the second optical deflection device includes multiple optical deflection units, the deflection partition includes multiple deflection sub-partitions corresponding to the positions on the multiple optical deflection units.

28. The transmitting module according to claim 27, wherein: The control device is specifically used to: respectively control the voltage on the two end electrodes of each deflection sub-partition, 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, so as to achieve the change of the second deflection angle of the corresponding deflection sub-partition to the light beam.

29. The transmitting module according to claim 20, wherein: The light deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarization grating, wherein the liquid crystal half-wave plate includes electrodes arranged on two sides opposite to each other and a half-wave plate liquid crystal layer arranged between the electrodes on both sides; One side electrode of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the other side electrode is a first whole electrode block, and each deflection sub-region corresponds to at least one first electrode block; each deflection sub-region includes a portion on the liquid crystal half-wave plate corresponding to the position of the at least one first electrode block and a portion on the liquid crystal polarization grating corresponding to the position of the at least one first electrode block; or The electrodes on both sides of the liquid crystal half-wave plate include a plurality of first electrode blocks, two opposing first electrode blocks form a first electrode pair, and each sub-deflection sub-area corresponds to at least one first electrode pair; each deflection sub-area includes a portion on the liquid crystal half-wave plate corresponding to the at least one first electrode pair and a portion on the liquid crystal polarization grating corresponding to the at least one first electrode pair; The deflection angle of the light beam caused by the corresponding deflection sub-region is adjusted by changing the voltage applied to the electrodes corresponding to the deflection sub-regions in the liquid crystal half-wave plate.

30. The transmitting module according to claim 20, wherein: The light deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarization grating plate; the liquid crystal half-wave plate includes electrodes arranged on two opposite sides and a half-wave plate liquid crystal layer arranged between the electrodes; the liquid crystal polarization grating plate includes electrodes arranged on two opposite sides and a grating liquid crystal layer arranged between the electrodes; One side electrode of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the other side electrode is a first whole electrode; one side electrode of the liquid crystal polarization grating plate includes a plurality of second electrode blocks, and the other side electrode is a second whole electrode; at least one second electrode block on the liquid crystal polarization grating plate and at least one first electrode block corresponding to a position on the liquid crystal half-wave plate form a block group; or The electrodes on both sides of the liquid crystal half-wave plate include a plurality of first electrode blocks, and two opposite first electrode blocks form a first electrode pair; the electrodes on both sides of the liquid crystal polarization grating plate include a plurality of second electrode blocks, and two opposite second electrode blocks form a second electrode pair; at least one second electrode pair on the liquid crystal polarization grating plate and at least one first electrode pair at a corresponding position on the liquid crystal half-wave plate form a block group; or One side electrode of the liquid crystal polarization grating comprises a plurality of second electrode blocks, and the other side electrode is a second whole electrode; both side electrodes of the liquid crystal half-wave plate comprise a plurality of first electrode blocks, and two opposing first electrode blocks form a first electrode pair; at least one second electrode block on the liquid crystal polarization grating and at least one first electrode pair corresponding to a position on the liquid crystal half-wave plate form a block group; or The electrodes on both sides of the liquid crystal polarization grating plate include a plurality of second electrode blocks, and two opposing second electrode blocks form a second electrode pair. The electrode on one side of the liquid crystal half-wave plate includes a plurality of first electrode blocks, and the electrode on the other side is a first whole electrode block. At least one second electrode pair on the liquid crystal polarization grating plate and at least one first electrode block corresponding to a position on the liquid crystal half-wave plate form a block group. Each deflection sub-partition corresponds to at least one block group; each deflection sub-partition includes a portion on the liquid crystal half-wave plate corresponding to the position of the block group, and a portion on the liquid crystal polarization grating corresponding to the position of the block group; The deflection angle of the light beam by the corresponding deflection sub-partition is adjusted by changing the voltage applied to the electrodes corresponding to the deflection sub-partition in the liquid crystal half-wave plate and the voltage applied to the electrodes corresponding to the deflection sub-partition in the liquid crystal polarization grating.

31. The transmitting module according to claim 29, wherein: The liquid crystal polarization grating plates of all the light deflection units in the second light deflection device are passive liquid crystal polarization grating plates, or the liquid crystal polarization grating plates of all the light deflection units in the second light deflection device are active liquid crystal polarization grating plates, or the liquid crystal polarization grating plates of some of the light deflection units in the second light deflection device are passive liquid crystal polarization grating plates, and the liquid crystal polarization grating plates of some of the light deflection units are active liquid crystal polarization grating plates; the liquid crystal material of the liquid crystal layer is nematic liquid crystal.

32. The transmitting module according to claim 29, wherein: The liquid crystal half-wave plate further comprises a first substrate and a second substrate arranged opposite to each other, wherein electrodes on both sides are respectively arranged on inner surfaces of the first substrate and the second substrate facing each other, and the inner surfaces are planes; The liquid crystal polarization grating plate further comprises a third substrate and a fourth substrate arranged opposite to each other. The electrodes on both sides are respectively arranged on the inner surfaces of the third substrate and the fourth substrate facing each other, and the inner surfaces are planes.

33. The transmitting module according to claim 29, wherein: The second light deflection device further includes a quarter wave plate arranged in front of the first liquid crystal half wave plate, for changing the polarization state of the light beam.

34. The transmitting module according to claim 29, wherein: The time for adjusting the second deflection angle of the light beam by the deflection partition is no longer than the time interval between two adjacent deflection periods of the deflection partition being scanned by the light beam.

35. The transmitting module according to claim 20, wherein: 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.

36. The transmitting module according to claim 1, wherein: The light beam is deflected at multiple different deflection angles in a time-sharing manner by the first light deflection device and the second light deflection device to scan a preset field of view range, wherein the length of the preset field of view range in the first direction is shorter than the length in the second direction.

37. The transmitting module according to claim 1, wherein: Also includes: Control devices; The control device is used to control the first light deflection device and the second light deflection device to deflect the light beam.

38. The transmitting module according to claim 37, wherein: When the first optical deflection device is an acousto-optic deflector, the control device is used to apply a driving signal to the acoustic wave generator of the first optical deflection device, and control the acoustic wave frequency of the acoustic wave generator acting on the acousto-optic crystal of the first optical deflection device through the driving signal, so as to change the deflection angle of the light beam by the first optical deflection device.

39. The transmitting module according to claim 1, wherein: Also includes: The temperature regulator 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.

40. The transmitting module according to claim 5, wherein: When the light beam emitted by the light source is linearly polarized light, it further includes a half-wave plate disposed between the collimating device and the first light deflecting device, 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 outgoing light beam of the collimator, and the electric field direction of the linearly polarized light forms a 45-degree angle with the fast axis of the 1 / 2 wave plate, or the electric field direction of the linearly polarized light forms a 45-degree angle with the slow axis of the 1 / 2 wave plate.

41. The transmitting module according to claim 1, wherein: The transmitting module is used in a laser radar system; or the transmitting module is a transmitting module in a laser radar system.

42. A laser radar system, characterized in that: It comprises a receiving module and a transmitting module as described in any one of claims 1 to 41, wherein the receiving module is configured to sense light signals from a field of view range and obtain three-dimensional information of the field of view range by processing and analyzing the light signals.

43. An electronic device, characterized in that: Including a lidar system as described in claim 42.

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