Optical scanning method

Abstract

The invention discloses a light scanning method, which comprises the following steps that: a first light deflection device deflects an incident light beam by a plurality of first deflection angles, and projects the deflected light beam to a polarization expanding device; the polarization expanding device amplifies the deflection angle of the deflected light beam in the corresponding deflection direction by a preset multiple, and projects the expanded light beam to the corresponding position of the second light deflection device; and the second light deflection device deflects the expanded light beam at a preset second deflection angle so as to project a scanning light beam. The light deflection angle can be continuously and finely adjusted within a larger angle range, and the structure of the light deflection device is miniaturized.

Description

Technical Field

[0001] This invention relates to the field of depth sensing technology, and in particular to an optical scanning method. Background Technology

[0002] In recent years, depth sensing systems, such as LiDAR, have begun to be commercialized on a large scale in fields such as optoelectronic sensing, intelligent manufacturing, 3D navigation, and imaging. Among them, the most commercially valuable and promising application is 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 within a wide field of view, ranging from approximately 300 meters away, and to have a signal update rate of ten to tens of frames per second to meet the application scenarios of high-speed vehicles. While meeting ranging performance requirements, the product also needs to have a relatively small size. To meet these performance requirements, current mainstream commercial vehicle-mounted LiDARs use mechanical rotating mirrors or MEMS galvanometer semi-solid-state scanning, illuminating targets within the scanned field of view in a time-division manner. However, due to the presence of rotating components, the system reliability and maintainability are not high.

[0003] Compared to traditional mechanical rotating mirror and semi-solid-state LiDAR, all-solid-state LiDAR offers significant advantages in system cost and reliability. Currently, the mainstream Direct Time-of-Flight (DTOF) Flash-type all-solid-state blind-spot LiDAR, such as the LiDAR disclosed in Chinese patent application CN202321460026.5, employs a wide-area emission method to cover the entire field of view. At the receiving end, a SPAD array is used to receive the reflected echo signals in a time-division and zone-division manner, ultimately achieving 3D imaging of targets within tens of meters. To meet vehicle navigation requirements without changing the frame rate, detection angle, and angular resolution, the detection power needs to be increased to achieve a detection range of hundreds of meters. This is currently limited by system heat dissipation capabilities and cost control requirements, making it difficult to achieve in engineering.

[0004] To improve the detection range of all-solid-state lidar, optical deflection structures are considered to amplify the optical deflection angle during all-solid-state optical scanning. For example, an acousto-optic deflector (AOD) combined with a liquid crystal polarization grating (LCPG) can be used for secondary deflection, which can achieve continuous and fine adjustment of the one-dimensional beam deflection angle within a large angle range. Summary of the Invention

[0005] The inventors of this application discovered that when using AOD combined with LCPG to achieve optical deflection, the beam deflected by AOD needs to travel a relatively long distance to distinguish beams with different deflection angles, resulting in a large distance between LCPG and AOD. The greater the distance between them, the larger the spot size of the beam after reaching LCPG, which leads to a large required size of LCPG. The large size of LCPG and the large distance between LCPG and AOD both result in a larger overall size of the optical deflection structure, making the overall shape of the lidar very large. This places higher demands on installation space, increases installation difficulty and equipment cost, and fails to meet the miniaturization requirements of lidar in various application scenarios.

[0006] In view of the above problems, the present invention is proposed to provide an optical deflection device, a transmitting module, a lidar system, an electronic device, and an optical scanning method that overcomes or at least partially solves the above problems.

[0007] This invention provides an optical deflection device, including a first optical deflection device, a second optical deflection device, and a polarization amplification device disposed on the light incident side of the second optical deflection device;

[0008] The first optical deflection device is configured to deflect the incident beam by multiple first deflection angles and project the deflected beam onto the polarization amplification device.

[0009] The polarization amplification device is configured to amplify the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, and project the amplified beam onto the corresponding position of the second optical deflection device.

[0010] The second optical deflection device is configured to deflect the amplified beam by a preset second deflection angle.

[0011] In some optional embodiments, the polarizing device includes at least one polarizing lens, which is a single lens or a combination of two or more lenses; the polarizing lens includes at least one or any combination of cylindrical lenses, spherical lenses, superlenses, and Fresnel lenses.

[0012] The at least one polarizing lens is configured to amplify the deflection angle of the light beam deflected by the first optical deflector by a preset factor in at least one of a first direction and a second direction that are perpendicular to each other.

[0013] In some optional embodiments, the focal length of the polarizing lens is set according to the magnification of the deflection angle; when the polarizing device includes two polarizing lenses, one side focal point of one polarizing lens coincides with one side focal point of the other polarizing lens, and the magnification is the ratio of the focal lengths of the two polarizing lenses.

[0014] In some optional embodiments, the distance between the first polarizing lens in the first optical deflection device and the polarizing device is the focal length of the first polarizing lens; the distance between two adjacent polarizing lenses is the sum of the focal lengths of the two adjacent lenses.

[0015] In some optional embodiments, the polarizing 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 polarizing cylindrical lens and a second polarizing cylindrical lens, configured to amplify the deflection angle of the light beam deflected by the first light deflecting device in a first direction by a preset factor, the preset factor being the ratio of the focal length of the first polarizing cylindrical lens to the focal length of the second polarizing cylindrical lens; the second cylindrical lens group includes a third polarizing cylindrical lens and a fourth polarizing cylindrical lens, configured to amplify the deflection angle of the light beam deflected by the first light deflecting device in a second direction by a preset factor, the preset factor being the ratio of the focal length of the third polarizing cylindrical lens to the focal length of the fourth polarizing cylindrical lens.

[0016] or

[0017] The polarizing device includes a first polarizing spherical lens and a second polarizing spherical lens, 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 factor, the preset factor being the ratio of the focal length of the first polarizing spherical lens to the focal length of the second polarizing spherical lens.

[0018] In some optional embodiments, the polarizing lens is configured to amplify the divergence angle of the beam deflected by the first optical deflector in the corresponding deflection direction by a preset factor, and the amplification factor of the divergence angle is the same as the amplification factor of the deflection angle of the beam in the deflection direction.

[0019] In some optional embodiments, the first optical deflection device is an acousto-optic deflection device, and the second optical deflection device is a liquid crystal polarization grating, wherein the liquid crystal material of the liquid crystal layer in the liquid crystal polarization grating sheet is a nematic liquid crystal or a blue phase liquid crystal.

[0020] In some alternative embodiments, the first optical deflector has a higher deflection accuracy for the light beam than the second optical deflector.

[0021] In some alternative embodiments, the first optical deflection device is configured as follows:

[0022] Among multiple different first deflection angles that deflect the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the beam along the deflection direction after being deflected by the first optical deflection device.

[0023] In some alternative embodiments, the first optical deflection device is configured to sequentially deflect the incident light beam in at least one of a first direction and a second direction by a plurality of different first deflection angles.

[0024] The second optical deflection device is configured to deflect the amplified beam at least in one of a first direction and a second direction by multiple different second deflection angles; the first direction and the second direction are perpendicular.

[0025] In some optional embodiments, the first optical deflector is configured to sequentially deflect the incident beam at multiple different first deflection angles in a first direction or a second direction; the second optical deflector is configured to deflect the polarized beam at multiple different second deflection angles in a two-dimensional array in the first and second directions; or

[0026] The first optical deflection device is configured to sequentially deflect the incident light beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflection device is configured to deflect the amplified light beam in a two-dimensional array in a first direction and a second direction by a plurality of different second deflection angles.

[0027] or

[0028] The first optical deflection device is configured to sequentially deflect the incident light beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflection device is configured to deflect the expanded light beam in a first direction or a second direction by a plurality of different second deflection angles.

[0029] or

[0030] The first optical deflection device is configured to deflect the incident light beam sequentially by a plurality of different first deflection angles in a first direction; the second optical deflection device is configured to deflect the expanded light beam by a plurality of different second deflection angles in a second direction.

[0031] or

[0032] The first optical deflection device is configured to deflect the incident beam by a plurality of different first deflection angles in a second direction; the second optical deflection device is configured to deflect the amplified beam by a plurality of different second deflection angles in a first direction.

[0033] In some alternative embodiments, the length of the light beam incident on the first light deflector in the first direction is less than the length in the second direction;

[0034] The first direction is the deflection direction of the incident beam by the first optical deflection device.

[0035] In some alternative embodiments, the second optical deflection device includes at least one optical deflection unit configured to deflect the amplified beam in a first direction or a second direction; or

[0036] The second optical deflection device includes at least two optical deflection unit groups, each optical deflection unit group including at least one optical deflection unit, wherein at least one optical deflection unit group is configured to deflect the expanded beam in a first direction, and at least one optical deflection unit group is configured to deflect the expanded beam in a second direction.

[0037] In some alternative embodiments, the first optical deflection device is configured to deflect the incident beam at multiple different first deflection angles within a deflection period and project the deflected beam onto a polarization expander so that the beam polarized by the polarization expander is incident at different positions of the second optical deflection device.

[0038] The deflection period is the time required for the first optical deflector to deflect all of the multiple different first deflection angles, or the deflection period is the time required for the first optical deflector to deflect a specified portion of the first deflection angles.

[0039] In some alternative embodiments, within a deflection period, the plurality of different first deflection angles of the beam vary from large to small, or from small to large, or vary according to a preset random rule in the corresponding deflection direction.

[0040] In some alternative embodiments, the second optical deflection device includes a plurality of deflection zones, each of which can be individually adjusted for the deflection angle of the incident beam; the plurality of deflection zones are configured such that the currently scanned deflection zone deflects the incident beam by the second deflection angle required.

[0041] The optical deflection device further includes a controller for controlling the currently scanned deflection partition in the second optical deflection device to deflect the incident beam, and for controlling at least one currently unscanned deflection partition to adjust its deflection angle to the beam, so that the deflection angle of at least one deflection partition to the incident beam is adjusted to the second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the incident beam and before the next deflection cycle has begun to be scanned by the incident beam.

[0042] In some optional embodiments, the controller is configured to control the first optical deflector to deflect the incident beam at multiple different first deflection angles in a deflection cycle, corresponding to multiple deflection zones incident on the second optical deflector, wherein the multiple deflection zones receive the incident beam and deflect the incident beam in a time-division manner.

[0043] In some optional embodiments, the first optical deflection device is configured to sequentially incident multiple incident beams with different first deflection angles onto corresponding deflection partitions in the second optical deflection device in a preset order within a deflection period; a deflection partition is configured to deflect the incident beams to a corresponding second deflection angle within a deflection period.

[0044] In some alternative embodiments, the plurality of deflection partitions are configured such that the plurality of second deflection angles deflecting the incident beam within a deflection cycle are all the same, all different, or partially the same and partially different.

[0045] In some alternative embodiments, a deflection partition may be configured to sequentially receive one, two or more incident beams with different first deflection angles corresponding to the expanded beams within a deflection period.

[0046] In some optional embodiments, the arrangement direction of the plurality of deflection partitions is consistent with the scanning direction of the plurality of incident beams with different first deflection angles.

[0047] In some optional embodiments, when the incident beam is a strip beam with an aspect ratio greater than a set threshold, the first optical deflection device is configured to deflect the incident beam at multiple different first deflection angles along a first direction within one deflection period to perform a one-dimensional scan of the second optical deflection device, and the multiple deflection partitions included in the second optical deflection device are arranged along the first direction of beam deflection.

[0048] When the incident beam is a non-strip beam with an aspect ratio within a set threshold range, the first optical deflection device is configured to deflect multiple different first deflection angles in a two-dimensional array scanning manner along a first direction and a second direction that are perpendicular to each other within one deflection cycle, so as to perform two-dimensional scanning on the second optical deflection device, and the multiple deflection partitions included in the second optical deflection device are arranged in a two-dimensional array along the first direction and the second direction; the first direction is the width direction of the beam, and the first direction is perpendicular to the second direction.

[0049] In some alternative embodiments, the plurality of deflection partitions are configured such that the number of incident beams received by each deflection partition is the same, different, or partially the same and partially different; correspondingly, the widths of the plurality of deflection partitions are the same, different, or partially the same and partially different.

[0050] 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 multiple incident beams with different first deflection angles, and the width of each deflection partition is determined according to the number of incident beams received and the width of the incident beams.

[0051] In some optional embodiments, the controller is specifically configured to: after determining that a deflection partition has completed the optical deflection of the current deflection cycle and is in a non-scanning state, control the deflection partition to adjust its deflection angle to the light beam, and adjust its deflection angle to the light beam to the second deflection angle required for the next deflection cycle before entering the scanning state in the next deflection cycle.

[0052] In some optional embodiments, the controller is specifically configured to: determine the deflection partition currently in a scanning state and the deflection partition in a non-scanning state based on the scanning position of the beam on the second optical deflection device; for the deflection partition in a non-scanning state, if the incident scanning sequence of the deflection partition is before that of the deflection partition in a scanning state, then the deflection partition is considered to have completed the beam deflection of the current deflection cycle.

[0053] In some optional embodiments, if a deflection zone is the deflection zone currently being scanned by the incident beam, then the deflection zone is determined to be in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state; or

[0054] If a deflection zone is the deflection zone that the incident beam is currently scanning or the next deflection zone to be scanned, then the deflection zone is determined to be in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state.

[0055] In some optional embodiments, the deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are determined as deflection partitions in the scanning state, and the remaining deflection partitions are determined as deflection partitions in the non-scanning state; the deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are deflection partitions that are adjacent in position.

[0056] In some optional embodiments, when the second optical deflection device has a non-partitioned structure, the control device is used to control the voltage applied to the electrodes of the second optical deflection device to adjust the refractive index of the medium in the second optical deflection device to the incident light beam, so as to adjust the deflection angle of the second optical deflection device to the incident light beam.

[0057] When the second optical 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 incident beam, so as to adjust the deflection angle of the deflection partition to the incident beam.

[0058] In some optional embodiments, when the second optical deflection device is 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 optical deflection device to adjust the arrangement direction of liquid crystal molecules in the liquid crystal polarization grating, so as to change the second deflection angle of the second optical deflection device on the incident beam.

[0059] When the second optical deflection device uses 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 liquid crystal molecules in the liquid crystal polarization grating, so as to change the second deflection angle of the incident beam by the deflection partition.

[0060] In some optional embodiments, when the second optical deflection device includes at least one optical deflection unit, the optical deflection unit includes a plurality of deflector partitions; the deflection partitions include deflector partitions in the at least one optical deflection unit that correspond to the position; the deflector partitions in at least one optical deflection unit included in a deflection partition can form a deflection optical path.

[0061] In some optional embodiments, when the second optical deflection device includes one optical deflection unit, the deflection partition is a deflector partition on the one optical deflection unit; when the second optical deflection device includes two optical deflection units, the deflection partition includes two deflector partitions on the two optical deflection units corresponding to each other; when the second optical deflection device includes multiple optical deflection units, the deflection partition includes multiple deflector partitions on the multiple optical deflection units corresponding to each other.

[0062] In some optional embodiments, the controller is specifically used to: control the voltage on the two end electrodes of each deflector section respectively, and change the deflection angle of at least one deflector section to the incident beam by changing the voltage on the two end electrodes of at least one deflector section, so as to change the second deflection angle of the corresponding deflection section to the incident beam.

[0063] In some optional embodiments, the optical deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarizing grating, wherein the liquid crystal half-wave plate includes electrodes disposed opposite to each other on both sides and a half-wave plate liquid crystal layer disposed between the two electrodes.

[0064] One side electrode of the liquid crystal half-wave plate includes multiple first electrode blocks, and the other side electrode is a first whole electrode. Each deflector partition corresponds to at least one first electrode block. Each deflector partition 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 polarizing grating corresponding to the position of the at least one first electrode block; or

[0065] The electrodes on both sides of the liquid crystal half-wave plate include multiple first electrode blocks, and two opposing first electrode blocks form a first electrode pair. Each sub-deflection zone corresponds to at least one first electrode pair. Each deflection zone includes a portion on the liquid crystal half-wave plate corresponding to the position of the at least one first electrode pair and a portion on the liquid crystal polarizing grating corresponding to the position of the at least one first electrode pair.

[0066] Specifically, the deflection angle of the beam by the corresponding deflector section is adjusted by changing the voltage applied to the electrode corresponding to the deflector section in the liquid crystal half-wave plate.

[0067] In some optional embodiments, the optical deflection unit includes a liquid crystal half-wave plate and a liquid crystal polarizing grating; the liquid crystal half-wave plate includes electrodes disposed opposite to each other on both sides and a half-wave plate liquid crystal layer disposed between the electrodes on both sides; the liquid crystal polarizing grating includes electrodes disposed opposite to each other on both sides and a grating liquid crystal layer disposed between the electrodes on both sides.

[0068] One side electrode of the liquid crystal half-wave plate includes multiple first electrode blocks, and the other side electrode is a first monolithic electrode; one side electrode of the liquid crystal polarizing grating includes multiple second electrode blocks, and the other side electrode is a second monolithic electrode; at least one second electrode block on the liquid crystal polarizing grating and at least one corresponding first electrode block on the liquid crystal half-wave plate form a block group; or

[0069] The electrodes on both sides of the liquid crystal half-wave plate each include multiple first electrode blocks, and two opposing first electrode blocks form a first electrode pair; the electrodes on both sides of the liquid crystal polarizing grating each include multiple second electrode blocks, and two opposing second electrode blocks form a second electrode pair; at least one second electrode pair on the liquid crystal polarizing grating and at least one corresponding first electrode pair on the liquid crystal half-wave plate form a block group; or

[0070] One side electrode of the liquid crystal polarizing grating includes multiple second electrode blocks, and the other side electrode is a second monolithic electrode; both sides of the liquid crystal half-wave plate include multiple first electrode blocks, and two opposing first electrode blocks form a first electrode pair; at least one second electrode block on the liquid crystal polarizing grating and at least one corresponding first electrode pair on the liquid crystal half-wave plate form a block group; or

[0071] Both sides of the liquid crystal polarizing grating include multiple second electrode blocks, and two opposing second electrode blocks form a second electrode pair. One side of the liquid crystal half-wave plate includes multiple first electrode blocks, and the other side electrode is a first whole electrode. At least one second electrode pair on the liquid crystal polarizing grating and at least one first electrode block corresponding to the position on the liquid crystal half-wave plate form a block group.

[0072] Each deflector partition corresponds to at least one block group; each deflector 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 polarizing grating plate corresponding to the position of the block group;

[0073] Specifically, the deflection angle of the beam by the corresponding deflector partition is adjusted by changing the voltage applied to the electrode corresponding to the deflector partition in the liquid crystal half-wave plate and the voltage applied to the electrode corresponding to the deflector partition in the liquid crystal polarizing grating.

[0074] In some optional embodiments, the liquid crystal polarization gratings of all the optical deflection units in the second optical deflection device are passive liquid crystal polarization gratings, or the liquid crystal polarization gratings of all the optical deflection units in the second optical deflection device are active liquid crystal polarization gratings, or the liquid crystal polarization gratings of some of the optical deflection units in the second optical deflection device are passive liquid crystal polarization gratings and the liquid crystal polarization gratings of some of the optical 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.

[0075] In some optional embodiments, the liquid crystal half-wave plate further includes a first substrate and a second substrate disposed opposite to each other, with electrodes on both sides respectively disposed on the inner surfaces of the first substrate and the second substrate facing each other, and the inner surfaces being planar.

[0076] The liquid crystal polarizing grating also includes a third substrate and a fourth substrate arranged opposite to each other, with electrodes on both sides respectively disposed on the inner surfaces of the third substrate and the fourth substrate facing each other, and the inner surfaces being planar.

[0077] In some alternative embodiments, the second optical 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 incident beam.

[0078] In some optional embodiments, the adjustment time of the second deflection angle of the incident beam by the deflection partition adjustment is not greater than the time interval between two adjacent deflection cycles of the deflection partition being scanned by the incident beam.

[0079] 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 multiple 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.

[0080] In some optional embodiments, the number D of the 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 completes one round of M deflection angles, and T is the time required for the second optical deflector to complete one deflection angle adjustment.

[0081] In some alternative embodiments, the first optical deflection device is configured to deflect the incident beam at multiple different first deflection angles along the first direction and project the deflected beam onto a polarizing device so that the beam polarized by the polarizing device is incident at different positions of the second optical deflection device.

[0082] The second optical deflection device is configured to deflect multiple incident 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; and to deflect each beam with a different first deflection angle to multiple different second deflection angles, thereby completing the scanning of multiple scanning partitions corresponding to the different multiple second deflection angles.

[0083] The scanning partition is rectangular, and the length of the beam after being deflected by the second deflection angle is equal to the length of one direction of the scanning partition.

[0084] In some alternative embodiments, the second optical deflection device is configured as follows:

[0085] Within one deflection cycle, multiple incident beams with different first deflection angles are deflected to the same second deflection angle, completing the scanning of a corresponding scanning zone within the field of view; the second deflection angle is different for the multiple incident beams with different first deflection angles in different deflection cycles; or

[0086] Within one deflection cycle, incident beams with multiple different first deflection angles are deflected to one of multiple different second deflection angles, and scan a portion of the corresponding scanning partition. Within one deflection cycle, the second deflection angles of the incident beams with multiple different first deflection angles may be the same or different. The second deflection angles of the incident beams with each first deflection angle are different in different deflection cycles.

[0087] In some optional embodiments, the above-described optical deflection device further includes a control device;

[0088] The control device is used to control the first optical deflection device and the second optical deflection device to deflect the light beam.

[0089] In some alternative embodiments, the controller is specifically used to perform the following control processes in parallel: controlling the currently scanned deflection partition in the second optical deflection device to deflect the incident beam, and controlling at least one currently unscanned deflection partition to adjust its deflection angle to the beam.

[0090] In some alternative embodiments, the controller includes a first control unit and a second control unit;

[0091] The first control unit is used to control the first optical deflection device to deflect multiple different first deflection angles in a deflection cycle, and to project the incident beam of each first deflection angle onto the corresponding deflection zone of the second optical deflection device.

[0092] The second control unit is used to control the plurality of deflection sections to receive the incident beam at different times and deflect the incident beam by the second deflection angle required, and to control the deflection sections to pre-adjust their deflection angles to the beam before being scanned by the incident beam; wherein, the deflection angle of at least one deflection section to the incident beam is adjusted to the second deflection angle required for the next deflection cycle after the current deflection cycle is scanned by the incident beam and before the next deflection cycle is scanned by the incident beam.

[0093] 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.

[0094] In some optional embodiments, the above-described optical deflection device further includes:

[0095] The temperature regulator is configured to change the time it takes for the second optical deflector to adjust its deflection angle by changing the temperature of the second optical deflector.

[0096] In some optional embodiments, the above-mentioned optical deflection device further includes: a collimating device disposed before the first optical deflection device to collimate the light beam in a first direction and a second direction that are perpendicular to each other;

[0097] The first direction is the direction in which the incident beam is deflected by the first optical deflection device, and the collimation of the collimated beam in the first direction is higher than that in the second direction.

[0098] In some alternative embodiments, the collimated beam has a divergence angle in the first direction that is less than 1 / 10 of the divergence angle in the second direction.

[0099] In some optional embodiments, the collimating device includes at least one collimating lens, and the emission position of the incident light beam is located 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.

[0100] In some alternative embodiments, the collimating device includes a first cylindrical lens and a second cylindrical lens, the first cylindrical lens being configured to collimate the beam along a first direction, and the second cylindrical lens being configured to collimate the beam along a second direction; or

[0101] Includes a spherical lens configured to collimate the light beam along a first direction and a second direction; or

[0102] It includes a cylindrical lens and a spherical lens, the cylindrical lens being configured to collimate the light beam along a first direction, and the spherical lens being configured to collimate the light beam along a first direction and a second direction.

[0103] In some optional embodiments, the following relationships are satisfied between the incident beam's emission width V1 in the first direction, its divergence angle θ1 in the first direction when emitted from the emission position, its beam waist diameter V2 in the first direction when the beam is incident on the first optical deflector, its divergence angle θ2 in the first direction when the beam is incident on the first optical deflector, and the focal length F2 of the collimating lens that collimates the beam along the first direction: θ2=V1 / F2,θ2V2=θ1V1.

[0104] In some optional embodiments, the following relationships are satisfied between the incident beam's emission length H1 in the second direction when emitted from the emission position, the divergence angle Θ1 in the second direction, the beam waist diameter H2 in the second direction when the beam is incident on the first optical deflector, the divergence angle Θ2 in the second direction when the beam is incident on the first optical deflector, and the focal length F1 of the collimating lens that collimates the beam along the second direction: Θ2=H1 / F1,Θ2H2=Θ1H1.

[0105] In some optional embodiments, the incident beam is a strip beam emitted from the emission position with an aspect ratio of 20:1 to 100:1; the beam incident on the first optical deflector has an aspect ratio of 3:1 to 1:2; and the scanning beam is a strip beam with an aspect ratio of 20:1 to 80:1.

[0106] In some optional embodiments, the aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; the aspect ratio of the scanning beam is 75:1; or

[0107] The aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; and the aspect ratio of the scanning beam is 25:1.

[0108] In some optional embodiments, when the light beam emitted by the light source is linearly polarized, a half-wave plate disposed between the collimating device and the first optical deflecting device is further included to change the polarization direction of the light beam.

[0109] The optical axis of the half-wave plate is perpendicular to the direction of the beam emitted from the collimating device, 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.

[0110] In some optional embodiments, the optical deflection device is used in the transmitting module of a lidar system; or the optical deflection device is an optical deflection device in the transmitting module of a lidar system.

[0111] This invention provides a transmitting module, including a light source and the aforementioned light deflection device;

[0112] The light source is used to emit a light beam to the light deflection device;

[0113] The light deflection device is used to deflect the light beam emitted by the light source to generate scanning light with different deflection angles and deflection angle switching sequences to achieve scanning of the field of view.

[0114] In some optional embodiments, the strip beam emitted by the light source has a shorter length along a first direction than along a second direction, where the first direction is the deflection direction of the incident beam by the first light deflecting device, and the second direction is perpendicular to the first direction; wherein,

[0115] The first optical deflecting device is configured to sequentially deflect the incident light beam at multiple different first deflection angles in a first direction; the second optical deflecting device is configured to deflect the polarized light beam at multiple different second deflection angles in a two-dimensional array in the first and second directions; or...

[0116] The first optical deflection device is configured to deflect the incident beam by a plurality of different first deflection angles in a first direction; the second optical deflection device is configured to deflect the amplified beam by a plurality of different second deflection angles in a second direction.

[0117] In some optional embodiments, the strip beam emitted by the light source has a shorter length along the second direction than along the first direction, the second direction being the deflection direction of the incident beam by the first light deflection device, and the second direction being perpendicular to the first direction; wherein,

[0118] The first optical deflecting device is configured to sequentially deflect the incident light beam by a plurality of different first deflection angles in the second direction; the second optical deflecting device is configured to deflect the polarized light beam by a plurality of different second deflection angles in the first and second directions in a two-dimensional array manner; or...

[0119] The first optical deflection device is configured to deflect the incident beam by a plurality of different first deflection angles in a second direction; the second optical deflection device is configured to deflect the amplified beam by a plurality of different second deflection angles in a first direction.

[0120] In some optional embodiments, the light source emits a non-strip beam with an aspect ratio within a set threshold range; wherein,

[0121] The first optical deflection device is configured to sequentially deflect the incident light beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflection device is configured to deflect the expanded light beam in a first direction or a second direction by a plurality of different second deflection angles.

[0122] The first optical deflection device is configured to sequentially deflect the incident light beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflection device is configured to deflect the amplified light beam in a two-dimensional array in a first direction and a second direction by a plurality of different second deflection angles.

[0123] The second direction is perpendicular to the first direction.

[0124] In some alternative embodiments, the light source includes any one or more combinations of edge-emitting lasers (EELs), vertical-cavity surface-emitting lasers (VCSELs), light-emitting diodes (LEDs), laser diodes (LDs), semiconductor lasers, and fiber lasers.

[0125] This invention provides a lidar system, including a receiving module and the aforementioned transmitting module;

[0126] The receiving module 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 sensed light signals.

[0127] This invention provides an electronic device including the aforementioned lidar system.

[0128] This invention provides an optical scanning method, comprising:

[0129] The first optical deflection device deflects the incident beam by multiple first deflection angles and projects the deflected beam onto the polarization amplification device;

[0130] The polarization amplification device amplifies the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, and projects the amplified beam onto the corresponding position of the second optical deflection device.

[0131] The second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam.

[0132] In some alternative embodiments, the first optical deflector deflects the incident beam by a plurality of first deflection angles, including:

[0133] The first optical deflection device deflects the incident light beam sequentially in at least one of the first and second directions by multiple different first deflection angles.

[0134] The second optical deflection device deflects the amplified beam by a preset second deflection angle, including:

[0135] The second optical deflection device deflects the amplified beam at least in one of the first and second directions by multiple different second deflection angles; the first and second directions are perpendicular.

[0136] In some optional embodiments, the polarizing device amplifies the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, including:

[0137] At least one polarizing lens amplifies the deflection angle of the light beam deflected by the first light deflection device by a predetermined factor in at least one of the mutually perpendicular first and second directions.

[0138] In some optional embodiments, at least one polarizing lens amplifies the deflection angle of the light beam deflected by the first optical deflecting device by a predetermined factor in at least one of a first direction and a second direction that are perpendicular to each other, including:

[0139] The first cylindrical lens group amplifies the deflection angle of the light beam deflected by the first light deflection device in the first direction by a preset factor. The first cylindrical lens group includes a first polarizing cylindrical lens and a second polarizing cylindrical lens. The preset factor is the ratio of the focal length of the first polarizing cylindrical lens to the focal length of the second polarizing cylindrical lens.

[0140] The second cylindrical lens group amplifies the deflection angle of the light beam deflected by the first light deflection device in the second direction by a preset factor. The second cylindrical lens group includes a third polarizing cylindrical lens and a fourth polarizing cylindrical lens. The preset factor is the ratio of the focal length of the third polarizing cylindrical lens to the focal length of the fourth polarizing cylindrical lens.

[0141] or

[0142] The first and second polarizing spherical lenses amplify the deflection angle of the light beam deflected by the first light deflecting device in the first and second directions by a preset factor, which is the ratio of the focal length of the first polarizing spherical lens to the focal length of the second polarizing spherical lens.

[0143] In some optional embodiments, the above method further includes:

[0144] The divergence angle of the beam deflected by the first optical deflection device is amplified by a preset factor in the corresponding deflection direction, and the amplification factor of the divergence angle is the same as the amplification factor of the deflection angle of the beam in that deflection direction.

[0145] In some alternative embodiments, within a deflection period, the deflection angle of the plurality of beams with different first deflection angles varies from large to small, or from small to large, or varies according to a preset random rule in each deflection direction.

[0146] In some alternative embodiments, multiple second deflection angles that deflect the beam within a deflection cycle may be the same, different, or partially the same and partially different.

[0147] In some optional embodiments, projecting the polarized beam onto the corresponding position of the second optical deflection device includes: the polarized beam being incident on the corresponding deflection zone of the second optical deflection device.

[0148] The second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam, including:

[0149] The controller controls multiple deflection zones in the second optical deflection device to receive amplified beams corresponding to beams with multiple different first deflection angles; the deflection angle of each deflection zone can be adjusted individually.

[0150] The second deflection angle required to deflect the beam by controlling the currently scanned deflection zone; and

[0151] Control at least one currently unscanned deflection zone to adjust the beam deflection angle to the second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the beam and before the next deflection cycle begins to be scanned by the beam.

[0152] In some optional embodiments, controlling the first optical deflector to deflect the incident beam by multiple first deflection angles includes: controlling the first optical deflector to deflect the incident beam by multiple different first deflection angles in a preset order within a deflection period.

[0153] Controlling multiple deflection zones in a second optical deflection device to receive multiple beams with multiple different first deflection angles includes: controlling the multiple deflection zones to receive multiple beams with multiple different first deflection angles at different times;

[0154] The deflection period is the time required for the first optical deflector to deflect all of the multiple different first deflection angles, or the deflection period is the time required for the first optical deflector to deflect a specified portion of the first deflection angles.

[0155] In some alternative embodiments, a deflection partition may sequentially receive one, two or more incident beams with different first deflection angles within a deflection period.

[0156] In some alternative embodiments, the plurality of deflection partitions are configured such that the plurality of second deflection angles deflecting the incident beam within a deflection cycle are all the same, all different, or partially the same and partially different.

[0157] In some alternative embodiments, the number of incident beams that each deflection partition can receive is the same, different, or partially the same and partially different; correspondingly, the widths of the plurality of deflection partitions are the same, different, or partially the same and partially different.

[0158] In some optional embodiments, controlling at least one currently unscanned deflection zone to adjust the deflection angle of the incident beam to a second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the beam and before the next deflection cycle begins to be scanned by the incident beam includes:

[0159] Once a deflection zone has completed the deflection of the incident beam in the current deflection cycle and is in a non-scanning state, the deflection zone is controlled to adjust its deflection angle to the beam. Before entering the scanning state in the next deflection cycle, its deflection angle to the beam is adjusted to the second deflection angle required for the next deflection cycle.

[0160] In some optional embodiments, if a deflection zone is the deflection zone currently being scanned by the incident beam, then the deflection zone is determined to be in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state; or

[0161] If a deflection zone is the deflection zone that the incident beam is currently scanning or the next deflection zone to be scanned, then it is determined that it is in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state.

[0162] In some optional embodiments, the deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are determined as deflection partitions in the scanning state, and the remaining deflection partitions are determined as deflection partitions in the non-scanning state; the deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are deflection partitions that are adjacent in position.

[0163] In some alternative embodiments, the voltage applied to the electrodes of each deflection zone is controlled to adjust the refractive index of the medium in the deflection zone to the incident beam, thereby adjusting the deflection angle of the deflection zone to the incident beam.

[0164] In some optional embodiments, when the second optical deflection device is a liquid crystal polarization grating, the voltage applied to the electrodes of each deflection partition is controlled to adjust the arrangement direction of liquid crystal molecules in the liquid crystal polarization grating, thereby changing the second deflection angle of the incident beam by the deflection partition.

[0165] In some optional embodiments, the second optical deflection device includes at least one optical deflection unit, which includes multiple deflector partitions. When the deflection partition includes a deflector partition corresponding to a position in the at least one optical deflection unit, the voltage on the two end electrodes of each deflector partition is controlled respectively. By changing the voltage on the two end electrodes of at least one deflector partition, the deflection angle of at least one deflector partition to the incident light beam is changed, thereby changing the second deflection angle of the corresponding deflector partition to the incident light beam.

[0166] In some alternative embodiments, where the second optical deflection device includes at least two optical deflection unit groups, each including at least one of the optical deflection units; the second deflection angle required to control the currently mapped deflection zone to deflect the incident beam includes:

[0167] The incident beam is deflected in the first direction by a second deflection angle required by the deflector partition of the optical deflection unit currently being scanned in at least one optical deflection unit group, and / or the incident beam is deflected in the second direction by a second deflection angle required by the deflector partition of the optical deflection unit currently being scanned in at least one optical deflection unit group, wherein the first direction and the second direction are perpendicular.

[0168] In some optional embodiments, the adjustment time of the second deflection angle of the incident beam by the deflection partition adjustment is not greater than the time interval between two adjacent scans of the deflection partition by the incident beam.

[0169] 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 multiple 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.

[0170] In some optional embodiments, the number D of the 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 completes one round of M deflection angles, and T is the time required for the second optical deflector to complete one deflection angle adjustment.

[0171] In some optional embodiments, the following control processes are performed in parallel: controlling the currently scanned deflection partition in the second optical deflection device to deflect the beam, and controlling at least one currently unscanned deflection partition to adjust its deflection angle to the beam.

[0172] In some optional embodiments, the field of view of the light scan is divided into multiple scanning partitions, the scanning partitions being rectangular, and the incident beam being a strip beam;

[0173] Scanning the field of view includes: deflecting multiple incident beams with different first deflection angles to the same second deflection angle to complete the scanning of one corresponding scanning partition of the field of view; and deflecting each beam with a first deflection angle of multiple incident beams with different first deflection angles to multiple different second deflection angles to complete the scanning of multiple scanning partitions corresponding to the multiple second deflection angles.

[0174] The length of the beam after the second deflection angle is equal to the length of one direction of the scanning partition.

[0175] In some optional embodiments, within one deflection cycle, incident beams with multiple different first deflection angles are deflected to the same second deflection angle to complete the scanning of a corresponding scanning partition of the field of view; each deflection cycle corresponds to different second deflection angles; different deflection cycles result in different second deflection angles for the incident beams with the multiple different first deflection angles; or

[0176] Within one deflection cycle, incident beams with multiple different first deflection angles are deflected to one of multiple different second deflection angles, and scan a portion of the corresponding scanning partition. Within one deflection cycle, the second deflection angles of the incident beams with multiple different first deflection angles may be the same or different. The second deflection angles of the incident beams with each first deflection angle are different in different deflection cycles.

[0177] In some optional embodiments, the method further includes: changing the temperature of the second optical deflector to change the time it takes for the second optical deflector to adjust its deflection angle.

[0178] In some alternative embodiments, the first optical deflector has a higher deflection accuracy for the light beam than the second optical deflector.

[0179] In some optional embodiments, among a plurality of different first deflection angles for deflecting the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the beam after deflection by the first optical deflection device along the deflection direction.

[0180] In some optional embodiments, the above method further includes:

[0181] Before the incident beam is incident on the first optical deflection device, the collimation device collimates the incident beam in the first direction and the second direction respectively.

[0182] The first direction is the direction in which the first optical deflection device deflects the incident beam, and the collimation requirement in the first direction is higher than the collimation requirement in the second direction.

[0183] In some alternative embodiments, the divergence angle of the collimated beam after collimation in the first direction is less than 1 / 10 of the divergence angle after collimation in the second direction.

[0184] In some optional embodiments, the collimating device collimates the incident beam in a first direction and a second direction, respectively, including:

[0185] One cylindrical lens collimates the incident beam along a first direction, and another cylindrical lens collimates the incident beam along a second direction; or

[0186] A spherical lens simultaneously collimates the incident beam along a first direction and a second direction; or

[0187] A cylindrical lens collimates the light beam along a first direction, and a spherical lens collimates the light beam simultaneously along both the first and second directions.

[0188] In some optional embodiments, the following relationships are satisfied between the incident beam's emission width V1 in the first direction, its divergence angle θ1 in the first direction when emitted from the emission position, its beam waist diameter V2 in the first direction when the beam is incident on the first optical deflector, its divergence angle θ2 in the first direction when the beam is incident on the first optical deflector, and the focal length F2 of the collimating lens that collimates the beam along the first direction: θ2=V1 / F2,θ2V2=θ1V1.

[0189] In some optional embodiments, the following relationships are satisfied between the incident beam's emission length H1 in the second direction when emitted from the emission position, the divergence angle Θ1 of the emission in the second direction, the beam waist diameter H2 in the second direction when the beam is incident on the first optical deflector, the divergence angle Θ2 in the second direction when the beam is incident on the first optical deflector, and the focal length F1 of the collimating lens that collimates the beam along the second direction: Θ2=H1 / F1,Θ2H2=Θ1H1.

[0190] In some optional embodiments, the incident beam is a strip beam emitted from the emission position with an aspect ratio of 20:1 to 100:1; the beam incident on the first optical deflector has an aspect ratio of 3:1 to 1:2; and the scanning beam is a strip beam with an aspect ratio of 20:1 to 80:1.

[0191] In some optional embodiments, the aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; the aspect ratio of the scanning beam is 75:1; or

[0192] The aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; and the aspect ratio of the scanning beam is 25:1.

[0193] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0194] The optical deflection device provided in this embodiment of the invention includes a polarization amplification device disposed between the first and second optical deflection devices to amplify the deflection angle of the beam deflected by the first optical deflection device. This allows adjacent beams deflected by the first optical deflection device to be distinguished within the shortest possible distance, thereby shortening the distance between the second and first optical deflection devices and making the overall structure of the optical deflection device smaller. By reducing the distance between the two stages of optical deflection devices through the polarization amplification device, the spot of the beam illuminating the second optical deflection device after being deflected by the first optical deflection device will become smaller as the distance decreases. The size of the second optical deflection device can also be smaller, further reducing the overall structure of the optical deflection device. This can meet the miniaturization requirements of vehicle-mounted LiDAR in applications such as intelligent driving. In addition, through the cooperation of the two stages of optical deflection devices and the polarization amplification device, continuous and fine adjustment of the beam deflection angle can be achieved within a wider angle range. At the same time, the angle interval between the beams deflected by the first optical deflection device can be smaller, achieving more refined optical scanning and improving the coverage effect of LiDAR optical scanning.

[0195] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0196] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. Attached Figure Description

[0197] 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:

[0198] Figure 1 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 1 of the present invention;

[0199] Figure 2 This is a three-dimensional structural diagram of the optical deflection device in Embodiment 1 of the present invention;

[0200] Figure 3 This is a three-dimensional structural diagram of the optical deflection device in Embodiment 1 of the present invention;

[0201] Figure 4 This is a specific structural example diagram of the optical deflection device in Embodiment 1 of the present invention;

[0202] Figure 5aThis is a schematic diagram of the optical path in the vertical direction in Embodiment 1 of the present invention;

[0203] Figure 5b This is a schematic diagram of the horizontal optical path in Embodiment 1 of the present invention;

[0204] Figure 6 This is a schematic diagram of the optical path when the polarization amplification device in Embodiment 1 of the present invention includes two positive lenses;

[0205] Figure 7 This is a schematic diagram of the optical path when the polarization amplification device in Embodiment 1 of the present invention includes a positive lens and a negative lens;

[0206] Figure 8 This is a schematic diagram of the structure of the first type of light source in Embodiment 1 of the present invention;

[0207] Figure 9 This is a schematic diagram of the second type of light source structure in Embodiment 1 of the present invention;

[0208] Figure 10 This is a schematic diagram of the third type of light source structure in Embodiment 1 of the present invention;

[0209] Figure 11 This is a schematic diagram of the fourth type of light source structure in Embodiment 1 of the present invention;

[0210] Figure 12 This is a schematic diagram of the fifth type of light source structure in Embodiment 1 of the present invention;

[0211] Figure 13 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 2 of the present invention;

[0212] Figure 14a This is a schematic diagram of the structure of the second optical deflection device with electrode blocks on one side of the liquid crystal half-wave plate in Embodiment 2 of the present invention;

[0213] Figure 14b This is a schematic diagram of the structure of the second optical deflection device with electrodes on both sides of the liquid crystal half-wave plate in Embodiment 2 of the present invention;

[0214] Figure 14c This is a schematic diagram of the structure of the second optical deflection device with one side electrode blocks of the liquid crystal half-wave plate and liquid crystal polarization grating in Embodiment 2 of the present invention;

[0215] Figure 14d This is a schematic diagram of the structure of the second optical deflection device in Embodiment 2 of the present invention, which is divided into two electrode blocks on both sides of the liquid crystal half-wave plate and the liquid crystal polarization grating.

[0216] Figure 15a This is a schematic diagram of the second optical deflection device structure using a passive liquid crystal grating in Embodiment 2 of the present invention;

[0217] Figure 15bThis is an example diagram showing the relationship between the applied voltage and the deflection angle of the second optical deflection device in Embodiment 2 of the present invention;

[0218] Figure 15c This is an example diagram showing the relationship between the applied voltage and the deflection angle of the second optical deflection device in Embodiment 2 of the present invention;

[0219] Figure 16 This is one of the example diagrams of the scanning path of the optical deflection unit in Embodiment 2 of the present invention;

[0220] Figure 17 This is the second example diagram of the scanning path of the optical deflection unit in Embodiment 2 of the present invention;

[0221] Figure 18 This is the third example diagram of the scanning path of the optical deflection unit in Embodiment 2 of the present invention;

[0222] Figure 19 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 3 of the present invention;

[0223] Figure 20 This is an example diagram of the beam deflection distribution in Embodiment 3 of the present invention;

[0224] Figure 21 This is a schematic diagram of the optical deflection device in Embodiment 4 of the present invention;

[0225] Figure 22 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 5 of the present invention;

[0226] Figure 23 This is a schematic diagram of the optical deflection device in Embodiment Six of the present invention;

[0227] Figure 24 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 7 of the present invention;

[0228] Figure 25 This is a schematic diagram of the composition and structure of the optical deflection device in Embodiment 8 of the present invention;

[0229] Figure 26 This is a schematic diagram of the structure of the transmitting module in an embodiment of the present invention;

[0230] Figure 27 This is a schematic diagram of the lidar system in an embodiment of the present invention;

[0231] Figure 28 This is a flowchart of the optical scanning method in an embodiment of the present invention.

[0232] Explanation of reference numerals in the attached figures:

[0233] 1. Transmitting module; 2. Receiving module; 10. Optical deflection device;

[0234] 100, First optical deflection device; 200, Second optical deflection device; 300, Light source; 400, Collimation device; 500, Polarizing device; 600, Control device; 110, First control unit; 128, Lens group; 1281, First polarizing lens; 1282, Second polarizing lens;

[0235] 210. Optical deflection unit; 220. Optical deflection unit group; 230. Second control unit; 240. Temperature regulator;

[0236] 211. First electrode block; 2110. First electrode pair; 212. Deflection zone; 2121. Deflector zone; 213. First monolithic electrode; 214. Liquid crystal half-wave plate; 215. Half-wave plate liquid crystal layer; 216. Liquid crystal polarizing 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 monolithic electrode; 310. Light-emitting unit. Detailed Implementation

[0237] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0238] To address the problems existing in the prior art, embodiments of the present invention provide an optical deflection device and a corresponding emission module.

[0239] Example 1

[0240] Embodiment 1 of the present invention provides an optical deflection device 10, the structure of which is described below. Figure 1 , Figure 2 and Figure 3 As shown, an optional structure of the optical deflection device includes a first optical deflection device 100 and a second optical deflection device 200, and a polarization amplification device 500 disposed on the incident light side of the second optical deflection device 200.

[0241] The first optical deflection device 100 is configured to deflect the incident beam by multiple first deflection angles and project the deflected beam onto the polarization expanding device 500.

[0242] The polarization amplification device 500 is configured to amplify the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, and project the amplified beam onto the corresponding position of the second optical deflection device 200.

[0243] A second light deflector 200, configured to deflect the beam after beam expansion by a preset second deflection angle to project a scanning beam.

[0244] Among them, the preset multiple U by which the beam deflector 500 amplifies the beam deflection angle can be set as needed. Optionally, 1 < U < 10. For example, it can be but is not limited to 2 times, 4 times, 5 times, etc.

[0245] Embodiment 1 of the present invention provides an optical deflector 10, the structure of which is as Figure 1 、 Figure 2 and Figure 3 shown. Another optional structure of the optical deflector includes a control device 600, a first light deflector 100, and a second light deflector 200, and a beam expander 500 provided on the incident light side of the second light deflector 200;

[0246] The first light deflector 100 is configured to deflect the incident beam by a plurality of first deflection angles and project the deflected beam onto the beam expander 500;

[0247] The beam expander 500 is configured to amplify the deflection angle of the deflected beam in the corresponding deflection direction by a preset multiple and project the beam after beam expansion onto a corresponding position of the second light deflector 200;

[0248] The second light deflector 200 is configured to deflect the beam after beam expansion by a preset second deflection angle to project a scanning beam;

[0249] The control device 600 is used to control the first light deflector 100 and the second light deflector 200 to deflect the beam. It can control the first light deflector 100 to deflect the incident beam and control the second light deflector 200 to deflect the beam after beam expansion.

[0250] For the optical deflector provided in Embodiment 1 of the present invention, referring to the optional specific structure shown in FIG. 5, on the basis of the above optional structure, it further includes: a collimating device 400, configured to collimate the beam before the beam enters the first light deflector 100; among them, the collimation degree of the collimated beam along the first direction is higher than the collimation degree along the second direction.

[0251] In this invention, to miniaturize the optical deflection device, a polarization amplification device 500 is added 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 and project the deflected beam onto the polarization amplification device 500. The polarization amplification device 500 can amplify the deflection angle of the light beam in the corresponding deflection direction by a preset factor and project the amplified beam onto 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 to project a scanning beam. Corresponding to the deflection of the light beam by the first optical deflection device 100 and the second optical deflection device 200 in at least one of the first and second directions, the polarization amplification device 500 amplifies the deflection angle of the light beam in at least one of the first and second directions by a preset factor. By using the polarization amplification device 500, beams deflected by adjacent deflection angles from the first optical deflection device can be separated within the shortest possible distance, thereby shortening the distance between the second and first optical deflection devices and making the overall structure of the optical deflection device smaller. With the reduced distance between the two stages of optical deflection devices, the spot of the beam illuminating the second optical deflection device 200 after being deflected by the first optical deflection device 100 will become smaller as the distance decreases. The size of the second optical deflection device 200 can also be reduced, further miniaturizing the overall structure of the optical deflection device and meeting the miniaturization requirements of automotive LiDAR in applications such as intelligent driving.

[0252] The aforementioned optical deflection device adds a polarization expanding device 500 between the first optical deflection device 100 and the second optical deflection device 200. The polarization expanding device 500 expands the deflection angle range of the first optical deflection device 100, making the area of ​​the rectangular region scanned by each deflection angle of the second optical deflection device 200 larger. This allows the second optical deflection device 200 to cover the entire field of view of the lidar with a smaller deflection angle, reducing the number of optical deflection units required for the second optical deflection device 200, simplifying the structure of the second optical deflection device 200, and reducing device cost.

[0253] The various optional structures of the above-mentioned optical deflection device and the components involved therein are described in detail below with reference to the accompanying drawings.

[0254] See Figure 4-8 As shown, the polarizing device 500 includes at least one polarizing lens, which can be a single lens or a combination of two or more lenses. The polarizing lens includes at least one or any combination of cylindrical lenses, spherical lenses, superlenses, and Fresnel lenses. When the polarizing lens includes a combination of two or more lenses, the combination of the two or more lenses can be considered as a single lens.

[0255] The aforementioned at least one polarizing lens is configured to amplify the deflection angle of the light beam deflected by the first light deflecting device 100 by a preset factor in at least one of a first direction and a second direction that are perpendicular to each other. The polarizing device 500 can also amplify the divergence angle of the light beam deflected by the first light deflecting device 100 in the corresponding deflection direction by a preset factor, and the divergence angle amplification factor is the same as the deflection angle amplification factor of the deflected light beam in that deflection direction. The focal length of the polarizing lens is set according to the amplification factor of the deflection angle. When the polarizing device 500 includes two polarizing lenses, one side focal point of one polarizing lens coincides with one side focal point of the other polarizing lens, and the amplification factor is the ratio of the focal lengths of the two polarizing lenses.

[0256] The positional relationship between the first optical deflecting device 100, the second optical deflecting device 200, and the polarizing device 500 can be designed according to the parameters of each device. Optionally, the distance between the first polarizing lens in the first optical deflecting device 100 and the polarizing device 500 is the focal length of the first polarizing lens; the distance between two adjacent polarizing lenses is the sum of the focal lengths of the two adjacent lenses. This allows the light beam deflected by the first optical deflecting device 100 to converge at its focal point after passing through the polarizing lens and then further diverge, so that the deflection angle of the light beam can be expanded to the required angle in a shorter distance. Therefore, the second optical deflecting device 200 can be set closer to the first optical deflecting device 100.

[0257] In some embodiments, the polarizing device includes two polarizing lenses, both of which are single lenses, both of which are combinations of two or more lenses, or one of the two polarizing lenses is a single lens and the other is a combination of two or more lenses.

[0258] Optionally, the polarizing device 500 may include two polarizing lenses that are combinations of two or more lenses. One possible configuration is that the polarizing 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 polarizing cylindrical lens and a second polarizing cylindrical lens, configured to amplify the deflection angle of the light beam deflected by the first light deflector in the first direction by a preset factor, the preset factor being the ratio of the focal length of the first polarizing cylindrical lens to the focal length of the second polarizing cylindrical lens; the second cylindrical lens group includes a third polarizing cylindrical lens and a fourth polarizing cylindrical lens, configured to amplify the deflection angle of the light beam deflected by the first light deflector in the second direction by a preset factor, the preset factor being the ratio of the focal length of the third polarizing cylindrical lens to the focal length of the fourth polarizing cylindrical lens. In practical applications, cylindrical lens groups can be set as needed. For example, a first cylindrical lens group can be set alone to amplify the beam polarization in the first direction; a second cylindrical lens group can be set alone to amplify the beam polarization in the second direction; or a first cylindrical lens group and a second cylindrical lens group can be set simultaneously to amplify the beam polarization in both the first and second directions.

[0259] Optionally, in a configuration where both polarizing lenses in the polarizing device 500 are single lenses, the polarizing device 500 includes a first polarizing spherical lens and a second polarizing spherical lens, configured to amplify the deflection angle of the beam deflected by the first light deflector in the first direction and the second direction by a preset factor. The preset factor is the ratio of the focal length of the first polarizing spherical lens to the focal length of the second polarizing spherical lens. Using spherical lenses as polarizing lenses can reduce the number of lenses used.

[0260] In some embodiments, see Figure 6 and Figure 7 As shown, the polarizing device 500 includes, for example, a first polarizing lens 1281 and a second polarizing lens 1282. The first polarizing lens 1281 and the second polarizing lens 1282 are arranged sequentially along the beam propagation direction. The focal point of one side of the first polarizing lens 1281 and the focal point of one side of the second polarizing lens 1282 coincide within the section between the first polarizing lens 1281 and the second polarizing lens 1282. That is, the beam deflected by the first or second optical deflecting device is first focused by the first polarizing lens 1281 onto the focal plane of the second polarizing lens 1282, and then amplified by the deflection angle after being refracted by the second polarizing lens 1282.

[0261] For example, in such Figure 6In the illustrated embodiment, both the first polarizing lens 1281 and the second polarizing lens 1282 have positive optical power. If the focal length of the first polarizing lens 1281 is F1 and the focal length of the second polarizing lens is F2, then the magnification factor M of the beam deflection angle by the polarizing device 500 is M = F1 / F2. That is, the angle at which the beam deflects from the center of the field of view by the first or second optical deflection device before entering the polarizing device 500 will be magnified by a factor of M after passing through the polarizing device 500.

[0262] For example, in such Figure 7 In the illustrated embodiment, the first polarizing lens 1281 has a positive optical power, and the second polarizing lens 1282 has a negative optical power. If the focal length of the first polarizing lens 1281 is F1 and the focal length of the second polarizing lens is F2, then the magnification factor M of the beam deflection angle of the polarizing device 500 is M = F1 / F2. That is, the angle at which the beam deflects from the center of the field of view before entering the polarizing device 500 is deflected by the first or second optical deflection device will be magnified by a factor of M after passing through the polarizing device 500.

[0263] It should be understood that the first polarizing lens 1281 can be a single lens or a lens group comprising multiple lenses. Similarly, the second polarizing lens 1282 can be a single lens or a lens group comprising multiple lenses.

[0264] It should be understood that the first polarizing lens 1281 and the second polarizing lens 1282 can both be rotationally symmetrical spherical mirrors about the optical axis, configured to magnify the deflection angle of the transmitted light beam by the same factor in all directions. For example, the first polarizing lens 1281 and the second polarizing lens 1282 magnify the deflection angle of the transmitted light beam by a factor of M in both the first and second directions, where the first direction is perpendicular to the second direction.

[0265] The aforementioned light deflection device 10 can generate a light beam from a light source. A light source control unit (not shown in the figure) can control the light source to emit light according to a preset time sequence. The length of the generated light beam along a first direction is less than its length along a second direction. Therefore, 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 perpendicular to the second direction; for example, the first direction can be vertical and the second direction can be horizontal. Optionally, the first direction can be horizontal and the second direction can be vertical. In some embodiments, the light source can include multiple light-emitting units, which are spliced ​​together to emit a light beam of the desired shape.

[0266] The light-emitting unit can be, for example, but not limited to, at least one of the following forms of light-emitting structures: Vertical Cavity Surface Emitting Laser (VCSEL), Edge Emitting Laser (EEL), Light Emitting Diode (LED), Laser Diode (LD), Semiconductor Laser, Fiber Laser, etc. The edge-emitting laser can be a Fabry Perot (FP) laser, a Distributed Feedback (DFB) laser, an Electro-absorption Modulated (EML) laser, etc., and this application does not limit this specific type.

[0267] In some embodiments, the first optical deflecting device 100 may optionally deflect the light beam periodically or non-periodically, or it may deflect multiple beams simultaneously in a certain order or time-division multiple times. Taking periodic time-division deflection as an example, the first optical deflecting device 100 is configured to deflect the incident light beam at multiple different first deflection angles in a preset order within a deflection period; the first optical deflecting device 100 deflects the incident light beam at multiple different first deflection angles within a deflection period, and projects the deflected light beam onto a polarizing device, so that the light beam amplified by the polarizing device is incident at different positions of the second optical deflecting device; the deflection period is the time required for the first optical deflecting device 100 to deflect all of the multiple different first deflection angles, or the deflection period is the time required for the first optical deflecting device 100 to deflect a specified portion of the first deflection angles.

[0268] Using a first optical deflector 100 as a fine-polarization device and a second optical deflector 200 as a coarse-polarization device, the light beam is deflected. Specifically, the first optical deflector 100 deflects the beam sequentially within a small deflection angle range at relatively fine angular intervals, and each deflection angle is relatively small. The second optical deflector 200 then deflects the beam deflected by the first optical deflector 100 sequentially within a larger deflection angle range at roughly the same time intervals. This allows for fine scanning over a wide field of view. Combining the fine and coarse polarization devices leverages the advantages of the fine polarization device—fast response speed and high number of resolvable points—to achieve fine scanning within a small angular range. By utilizing the high diffraction efficiency and large deflection angle of the coarse polarization device, the scanning range can be extended to cover a wide field of view with a smaller number of deflection angles. In some embodiments, the second optical deflecting device 200 is configured to further deflect the beam deflected by the first optical deflecting device 100 to form a beam that scans the field of view. In this case, the first optical deflecting device 100 can finely deflect the beam by multiple first deflection angles near a coarse second deflection angle by the second optical deflecting device 200, ultimately achieving quasi-continuous fine scanning within a large deflection angle range of the second optical deflecting device 200 with the deflection accuracy of the first optical deflecting device 100. The second optical deflecting device 200 can deflect the expanded beam by multiple different second deflection angles in at least one of the first and second directions. That is, the first optical deflecting device 100 can deflect the beam in one or two dimensions, and the second optical deflecting device 200 can also deflect the beam in one or two dimensions, which can reduce the number of deflection angles of the second optical deflecting device 200 and make the second optical deflecting device 200 thinner. It is understood that in some other embodiments, depending on the needs of the actual application, the first optical deflecting device 100 may also be configured to perform a secondary deflection on the beam deflected by the second optical deflecting device 200, and this application does not limit this. The deflection dimensions of the first optical deflecting device 100 and the second optical deflecting device 200 may, for example, but not limited to, one of the following:

[0269] Method 1: The first optical deflection device 100 is configured to deflect the incident beam sequentially by multiple different first deflection angles in the first or second direction; the second optical deflection device 200 is configured to deflect the amplified beam by multiple different second deflection angles in the first and second directions in a two-dimensional array manner.

[0270] Method 2: The first optical deflection device 100 is configured to deflect the incident beam in a two-dimensional array in the first and second directions by a plurality of different first deflection angles; the second optical deflection device 200 is configured to deflect the amplified beam in a two-dimensional array in the first and second directions by a plurality of different second deflection angles.

[0271] Method 3: The first optical deflection device 100 is configured to deflect the incident beam in a two-dimensional array in the first and second directions by a plurality of different first deflection angles; the second optical deflection device 200 is configured to deflect the amplified beam in the first or second direction by a plurality of different second deflection angles.

[0272] Method 4: The first optical deflector 100 is configured to deflect the incident beam by a plurality of different first deflection angles in a first direction; the second optical deflector 200 is configured to deflect the amplified beam by a plurality of different second deflection angles in a second direction.

[0273] Method 5: The first optical deflector 100 is configured to deflect the incident beam by a plurality of different first deflection angles in a second direction; the second optical deflector 200 is configured to deflect the amplified beam by a plurality of different second deflection angles in a first direction.

[0274] The first optical deflector 100 is configured to sequentially deflect an incident light beam at least one of a first direction and a second direction by a plurality of different first deflection angles. The first optical deflector 100 can deflect the incident light beam by a plurality of preset first deflection angles within each preset deflection cycle and at preset deflection time intervals, and project the deflected light beam onto the polarizer 500. The first optical deflector 100 can deflect the light beam by a plurality of first deflection angles within a preset angle range along the first direction. For example, within the range of -1.5 to +1.5 degrees, the light beam can be deflected by a plurality of first deflection angles with certain intervals. The first deflection angles are an angle sequence, such as -1.5, -1.0, -0.5, 0, 0.5, 1, 1.5, etc., and the angle intervals can be set as needed. In some embodiments, the first optical deflector 100 can repeatedly deflect all or part of the plurality of first deflection angles according to a plurality of preset deflection cycles. The deflection cycle refers to the time required for the first optical deflector 100 to deflect the light beam by a plurality of first deflection angles within the preset angle range. Alternatively, the deflection period can be described as the time required for the first optical deflecting device 100 to sequentially deflect the light beam by all or part of a preset number of first deflection angles. It should be understood that the duration of any two different deflection periods can be set to be the same or different; within any two different deflection periods, the number and order of the first deflection angles deflected by the first optical deflecting device 100 can be set to be the same or different. Within one deflection period, the first optical deflecting device 100 can also repeatedly deflect the light beam by one or more of the first deflection angles two or more times. After completing one deflection period, the first optical deflecting device 100 can enter the next deflection period and continue to deflect the light beam in a new round according to the corresponding set number and order of the first deflection angles.

[0275] The first optical deflector 100 is configured such that, among a plurality of different first deflection angles for deflecting the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the beam after deflection by the first optical deflector along the deflection direction. This allows the edges of two adjacent beams deflected by the first optical deflector to overlap slightly, thereby ensuring that the scanning area is fully covered and no scan is missed.

[0276] The length of the light beam incident on the first light deflector 100 in the first direction is less than the length in the second direction; the first direction is the deflection direction of the incident light beam by the first light deflector 100.

[0277] In the aforementioned optical deflection device, the deflection accuracy of the first optical deflection device 100 for a pair of light beams is higher than that of the second optical deflection device 200 for a pair of light beams.

[0278] Optionally, the second optical deflection device 200 includes at least one optical deflection unit, which is configured to deflect the expanded beam in a first direction or a second direction; or the second optical deflection device 200 includes at least two optical deflection unit groups, each optical deflection unit group including at least one optical deflection unit, wherein at least one optical deflection unit group is configured to deflect the expanded beam in a first direction, and at least one optical deflection unit group is configured to deflect the expanded beam in a second direction.

[0279] The second optical deflection device 200 can adopt a partitioned structure or an unpartitioned structure.

[0280] The aforementioned optical deflection device, through the cooperation of two stages of optical deflection devices and a polarization expander, can achieve continuous and precise adjustment of the beam deflection angle over a wider angle range. Simultaneously, it can reduce the angle interval between the deflection of the beam by the first optical deflection device, achieving more refined optical scanning and improving the coverage effect of lidar optical scanning. The deflection angle range of the beam by the first optical deflection device 100 is relatively small. The polarization expander is positioned between the first optical deflection device 100 and the second optical deflection device 200. The deflection angle range of the beam entering the polarization expander is also correspondingly small, concentrated near the optical axis. In this case, the polarization expander can better achieve the preset deflection multiple. Compared to placing the polarizing device after the second optical deflector 200, the deflection efficiency of the beam is higher and the overall structure of the device is simpler. This is because if the polarizing device is placed after the second optical deflector 200, the deflection angle range of the beam emitted from the second optical deflector 200 is larger, and the incident angle range of the beam entering the polarizing device is also larger. At this time, the efficiency of the edge beam with a large deflection angle will be reduced. In order to ensure that such edge beams can pass through the secondary lens in the polarizing device, more intermediate lenses need to be set to adjust the beam, and the entire polarizing optical system will become more complicated.

[0281] In some optional embodiments, a specific structural example of the above-described optical deflection device can be found below. Figure 4 As shown, it includes a collimating device 400, a first optical deflecting device 100, a polarization expanding device 500, and a second optical deflecting device 200. This optical deflecting device is related to... Figure 1The difference in the device shown is that a collimating device 400 is provided between the light source 300 and the first light deflecting device 100, and is configured to collimate the light beam before it enters the first light deflecting device 100; the light beam emitted by the light source 300 can be collimated in a first direction and a second direction that are perpendicular to each other; wherein, the collimation requirement in the first direction is higher than the collimation requirement in the second direction, that is, the collimation of the collimated light beam along the first direction is higher than the collimation along 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, and the collimated light beam is then incident on the first light deflecting device 100. Figure 4 The optical deflection device shown is illustrated by using two cylindrical lenses as the collimating device, two spherical lenses as the polarizing device, and a partitioned structure as the second optical deflection device 200. Figure 4 The optical path of the optical deflection device shown in the vertical direction (first direction) is shown in the figure. Figure 5a As shown, the optical path in the horizontal direction (second direction) is shown in the diagram. Figure 5b As shown. After adding the collimating device, the incident beam of the collimating device 400 is the beam emitted by the light source 300, the incident beam of the first optical deflecting device 100 is the beam collimated by the collimating device 400, and the incident beam of the polarizing device 500 is the beam deflected by the first optical deflecting device 100. The incident beam of the second optical deflecting device 200 is the beam polarized by the polarizing device 500.

[0282] In some optional embodiments, when the collimating device 400 collimates the beam, its collimation can be measured by the size of the divergence angle. Based on the general laws of light propagation, in a certain direction, the higher the collimation, the smaller the divergence angle of the beam, and the larger the size of the beam in that direction. Conversely, in a certain direction, the lower the collimation, the larger the divergence angle of the beam, and the smaller the size of the beam in that direction. The first optical deflection device 100, taking an AOD device as an example, typically has an aperture aspect ratio smaller than the strip beam emitted after the light sources are spliced ​​together. In order to fully deflect the beam, a high collimation requirement and a small beam divergence angle are required in the deflection direction, while a lower collimation requirement and a larger beam divergence angle are required in the non-deflection direction. Therefore, a suitable collimation device can be designed to strictly collimate the beam only in the deflection direction of the first optical deflection device 100, without strict collimation in other directions. This allows the collimated beam to meet the deflection requirements of the AOD device in the deflection direction, improving the efficiency of the beam deflection by the AOD device. It also allows the collimated beam to naturally diffuse with a large divergence angle in the non-deflection direction, which is convenient for the subsequent formation of a strip beam.

[0283] Optionally, the divergence angle of the collimated beam after collimation in the first direction is less than 1 / 10 of the divergence angle after collimation in the second direction. This allows the size of the beam incident on the first light deflection device 100 to be better suited to the size of its aperture.

[0284] The collimating device 400 includes at least one collimating lens, such as two cylindrical lenses, a spherical lens, or a combination of a cylindrical lens and a spherical lens, to collimate the strip beam emitted by the light source in a first and a second direction that are perpendicular to each other. Optionally, to achieve collimation of the beam according to collimation requirements, the positional relationship between the collimating device 400 and the light source 300 can be set according to the beam collimation requirements. One optional setting is that the light source 300 is positioned 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 coincide.

[0285] Optionally, the collimating device 400 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. In this case, the first and second cylindrical lenses can be selected with different focal lengths to achieve output light beams with different collimations in different directions. The cylindrical lens with the smaller focal length is positioned closer to the light source, while the cylindrical lens with the larger focal length is positioned relatively farther from the light source. The focal planes of the two cylindrical lenses can coincide, and the light source is located at the focal plane.

[0286] 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, the focal length of which is selected according to the collimation requirements in both directions to satisfy those requirements. Optionally, at least in the direction with the higher collimation requirement, the collimated light beam achieves the required collimation.

[0287] Optionally, the collimating device 400 includes a cylindrical lens and a spherical lens. 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 simultaneously along both the first and second directions. In this case, collimation is achieved simultaneously using both the cylindrical and spherical lenses in directions with high collimation requirements, and simultaneously using the spherical lens in directions with low collimation requirements, thereby obtaining output light beams with different collimations in different directions. Optionally, the focal planes of the cylindrical and spherical lenses can coincide, and the light source is positioned at the focal plane.

[0288] In some embodiments, the collimating device 400 is configured to collimate a beam with an aspect ratio of A into a beam with an aspect ratio of B, where A>B; the first optical deflecting device 100 and the second optical deflecting device 200 are configured to deflect the beam with an aspect ratio of B and project a beam with an aspect ratio of C, where C>B. That is, if the aspect ratio of the beam incident on the collimating device 400 is A, after being collimated by the collimating device 400, the aspect ratio of the beam exiting the collimating device or incident on the first optical deflecting device will decrease to B. After being deflected by the first optical deflecting device and the second optical deflecting device, the aspect ratio of the scanning beam projected to the distance will increase again to C, thus forming a long strip beam.

[0289] The focal length of the collimating lens in the collimating device 400 can be selected as needed, for example, based on the divergence angle and size of the collimated beam, or the divergence angle and size of the beam before collimation. See also Figure 5a The vertical optical path shown and Figure 5b The horizontal optical path shown is illustrated using two cylindrical lenses as an example. Using a spherical lens for the collimating device 400 can reduce the number of lenses required.

[0290] In the vertical direction: the luminous width V1 of the incident beam emitted from its position in the first direction (i.e., the luminous width V1 of the light source in the vertical direction (first direction), the divergence angle θ1 of the light source in the vertical direction (first direction), collimated by a cylindrical lens with a focal length of F2, the beam waist diameter V2 of the beam when it is incident on the first light deflecting device 100 in the first direction, the divergence angle θ2 of the beam when it is incident on the first light deflecting device 100 in the first direction, and the focal length F2 of the collimating lens that collimates the beam along the first direction satisfy the following relationships: θ2=V1 / F2, 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.

[0291] In the horizontal direction: the luminous length H1 of the incident beam emitted from its position in the second direction (i.e., the luminous length H1 of the light source in the horizontal direction (second direction), the divergence angle Θ1 of the light source in the horizontal direction (second direction), collimated by a cylindrical lens with a focal length of F1, the beam waist diameter H2 of the beam when it is incident on the first light deflecting device 100 in the second direction, the divergence angle Θ2 of the beam when it is incident on the first light deflecting device 100 in the second direction, and the focal length F1 of the collimating lens that collimates the beam along the second direction satisfy the following relationships: Θ2=H1 / F1, 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 as the focal length F1.

[0292] In some embodiments, when selecting a strip light source, H1 >> V1 can be chosen. Correspondingly, since Θ1 ~ θ1, by selecting appropriate lens focal lengths F1 and F2, Θ2 >> θ2 can be achieved, so that the light spot will appear as a strip in the far field after passing through the subsequent spherical lens.

[0293] In the aforementioned optical deflection device, the light source can emit a beam with a certain aspect ratio. When the beam is incident on the first optical deflection device 100, the aspect ratio can also be within a certain range to adapt to the 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 beam with a certain aspect ratio is formed.

[0294] In some embodiments, the light beam emitted by the light source 300 is a strip beam, that is, the incident beam is a strip beam when emitted from the emission position, with an aspect ratio of 20:1 to 100:1; the aspect ratio of the beam incident on the first light deflector 100 is 3:1 to 1:2; and the scanning beam is a strip beam with an aspect ratio of 20:1 to 80:1. By using beams with aspect ratios within a certain range, the two light deflectors deflect the beams, optionally combining collimation and / or polarization expansion to form a strip scanning beam with a certain aspect ratio. This allows the scanning beam to cover one directional length of a scanning partition within the field of view, thereby achieving regional scanning of the field of view.

[0295] Optionally, the aspect ratio of the beam emitted by the light source 300 is 50:1; the aspect ratio of the beam incident on the first light deflection device 100 is 5:2; and the aspect ratio of the scanning beam is 75:1; or optionally, the aspect ratio of the beam emitted by the light source 300 is 50:1; the aspect ratio of the beam incident on the first light deflection device 100 is 5:2; and the aspect ratio of the scanning beam is 25:1.

[0296] In some embodiments, when the light beam emitted by the light source is linearly polarized, the above-described light deflection device further includes a half-wave plate disposed between the collimating device 400 and the first light deflection device 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 from the collimating device 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.

[0297] In schemes where the first optical deflector 100 and the second optical deflector 200 deflect the light beam, it is sometimes necessary to rotate the polarization direction of the beam. This can be achieved by placing a half-wave plate between the collimator 400 and the first optical deflector 100. Taking an EEL light source as an example, the beam emitted by an EEL is generally approximately TE-mode linearly polarized light, with the electric field direction parallel to the slow axis direction, which in this application is, for example, horizontal. On the other hand, the first optical deflector 100 is generally designed to have the incident light polarization direction parallel to the ultrasonic wave direction, which in this application is, for example, vertical. In this case, the polarization direction needs to be rotated by 90 degrees before the beam incident, which can be achieved by setting a half-wave plate to rotate the polarization direction. The optical axis of the half-wave plate is perpendicular to the direction of the emitted beam, 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. Placing the half-wave plate after the collimator 40° ensures a small divergence angle when the incident beam enters the half-wave plate, preventing additional optical power loss due to a large divergence angle. The half-wave plate can be, for example, but not limited to, a zero-order wave plate.

[0298] Optionally, the first optical deflecting device 100 deflects the light beam by multiple first deflection angles within one deflection cycle, and the second optical deflecting device 200 re-deflects the light beam deflected by the first optical deflecting device 100 at the same or different second deflection angles within the same deflection cycle. Optionally, the second deflection angle re-deflected by the second optical deflecting device 200 on the light beam deflected by the first optical deflecting device 100 within the same deflection cycle can be one, two, or more.

[0299] In some embodiments, the deflection speed of the first optical deflector 100 on the light beam is higher than that of the second optical deflector 200 on the light beam. Around each second deflection angle of the coarse deflection by the second optical deflector 200, the first optical deflector 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 by the first optical deflector 100 is several times greater than the number of coarse deflections by the second optical deflector 200. Thus, using the faster-deflecting first optical deflector 100 for a greater number of fine deflections can reduce the optical deflection time required for scanning.

[0300] In some embodiments, the first optical deflection device 100 is configured such that, among a plurality of different first deflection angles for deflecting the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the incident beam along the deflection direction, thereby enabling a small overlap between the edges of two adjacent beams deflected by the first optical deflection device 100, thereby ensuring that the scanning area is fully covered and no scan is missed.

[0301] In some embodiments, the divergence angle of the strip beam formed by the polarizing device 500 along the second direction is greater than or equal to the angular interval between two adjacent second deflection angles of the second optical deflecting device 200 along the second direction. This allows the edges of two adjacent beams deflected by two adjacent second deflection angles in the second direction to partially overlap, thereby ensuring that the scanning area is fully covered and no areas are missed.

[0302] In some embodiments, the deflection angle range of the first optical deflecting device 100 deflecting the light beam along the first direction is greater than or equal to the angular interval between two adjacent second deflection angles of the second optical deflecting device 200 along the first direction. This allows for a small overlap between the edges of the scanning area covered by the light beams deflected by the two adjacent second deflection angles in the first direction, ensuring full coverage of the scanning area and preventing any missed scans.

[0303] In the case of an incident beam that is a strip beam, the above-mentioned light deflection device is configured such that: the first light deflection device 100 is configured to deflect the incident beam at multiple different first deflection angles along a first direction, and project the deflected beam onto the polarization expander 500, so that the beam amplified by the polarization expander 500 is incident at different positions of the second light deflection device 200; the second light deflection device 200 is configured to deflect the deflected beams incident at different first deflection angles at the same second deflection angle to complete the scanning of a corresponding scanning zone within the field of view; and so on, the second light deflection device 200 can deflect the deflected beams incident at different first deflection angles at multiple second deflection angles to complete the scanning of multiple scanning zones corresponding to different multiple second deflection angles.

[0304] In practical applications, the second optical deflection device 200 can be configured to deflect 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; by deflecting light beams incident at each position at different positions by multiple different second deflection angles, multiple scanning partitions corresponding to different second deflection angles can be completed; 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. Optionally, the second optical deflecting device 200 is configured to deflect multiple beams with different first deflection angles to the same second deflection angle within one deflection cycle, thereby completing the scanning of a corresponding scanning partition of the field of view; the second deflection angles deflected by the multiple beams with different first deflection angles are different in different deflection cycles; or within one deflection cycle, multiple beams with different first deflection angles are deflected to one of multiple different second deflection angles respectively, thereby scanning a portion of the corresponding scanning partition respectively; wherein, within one deflection cycle, the second deflection angles deflected by the multiple beams with different first deflection angles are the same or different; the second deflection angles deflected by each beam with a first deflection angle are different in different deflection cycles.

[0305] In the aforementioned optical deflection device, the light beam is deflected at multiple different angles by the first optical deflector 100 and the second optical deflector 200 to scan a preset field of view. The preset field of view has a length in the first direction that is shorter than its length in the second direction. By setting the longer second direction of the strip beam formed by the two-stage deflection to be consistent with the longer direction of the entire field of view to be scanned, the number of angles by which the second optical deflector deflects the strip beam along the second direction can be reduced, thereby reducing the size and cost of the second optical deflector and shortening the beam deflection time required for scanning.

[0306] It is understood that, in some embodiments, when completing the scanning of the entire field of view, the angle and order of beam deflection can be configured by the first light deflector 100 and the second light deflector 200 to complete the scanning of one scanning area first, then proceed to the scanning of the next scanning area, and so on, until all scanning areas are scanned. That is, the second light deflector 200 can deflect beams incident at different first deflection angles to the same second deflection angle within one deflection cycle, so as to complete the scanning of a corresponding scanning partition in one deflection cycle. Thus, multiple different scanning partitions can be scanned after multiple deflection cycles.

[0307] See Figure 2 As shown, the entire field of view can be divided into multiple scanning zones. Figure 2Taking 16 scanning partitions as an example, corresponding to 16 grids in the diagram. The second optical deflection device 200 deflects the light by 2 second deflection angles in the first direction and by 8 second deflection angles in the second direction, thus achieving [the desired effect]. Figure 2 The scanning of the 16 scanning partitions shown corresponds to a second deflection angle. That is, multiple first deflection angles deflected by the first optical deflector 100 are deflected by the second optical deflector 200 to the same second deflection angle, thus covering one scanning partition. 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. In actual scanning, within the first deflection cycle, the beams deflected by the first optical deflector 100 at multiple first deflection angles are all deflected by the first second deflection angle to complete the scanning of the first square in the first row; within the second deflection cycle, the beams deflected by the first optical deflector 100 at multiple first deflection angles are all deflected by the second second deflection angle to complete the scanning of the second square in the first row; and so on. In the fourth deflection cycle, the beams deflected by the first optical deflector 100 at multiple first deflection angles are all deflected by the fourth second deflection angle, and so on. Figure 2 The scan of the fourth square in the first row is completed; after 16 deflection cycles, the scan of all the scan partitions corresponding to the 16 squares is completed.

[0308] In some other embodiments, the second optical deflector 200 can deflect a deflected beam incident at different first deflection angles to two or more different second deflection angles within one deflection cycle. In this case, instead of focusing on scanning a single corresponding scanning partition within one deflection cycle, it skips between scanning different positions within two or more different scanning partitions along the deflection direction of the first optical deflector 100. Thus, after multiple deflection cycles, scanning of all scanning partitions can be completed. For example, in this embodiment, within one deflection cycle, the beams formed by the first optical deflector 100 and the second optical deflector 200 scan the scanning partitions corresponding to different second deflection angles, and the scanned positions are relatively far apart, which can reduce crosstalk between adjacent scans.

[0309] See Figure 3As shown, the entire field of view can be divided into multiple scanning zones, with 16 scanning zones corresponding to the 16 grids in the diagram. Within one deflection cycle, the second optical deflector 200 can deflect multiple beams of light with first deflection angles deflected by the first optical deflector 100 at different second deflection angles, so as to alternately scan different scanning zones. For example, within the first deflection cycle, the second optical deflector 200 deflects the beam with the first first deflection angle at the first second deflection angle to scan a small strip area in the first square of the first row; it deflects the beam with the second first deflection angle at the second second deflection angle to scan a small strip area in the second square of the first row; and so on. Within the second deflection cycle, the second optical deflector 200 deflects the beam with the first first deflection angle at the first second deflection angle to scan a small strip area in the second square of the first row; it deflects the beam with the second first deflection angle at the second second deflection angle to scan a small strip area in the third square of the first row; and so on. By doing this, 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.

[0310] Compared to scanning with a circular or near-circular beam, using a long, narrow beam to scan the field of view and deflecting the beam at the width of the beam via the AOD (Aspect-Oriented Deflection) significantly reduces the number of angles the LCPG deflects in the first and second directions. For example... Figure 2 and Figure 3 As shown, the LCPG deflects at 16 angles, 8 in the horizontal direction and 2 in the vertical direction. The number of angles that the LCPG deflects is related to the number of layers it contains (i.e., the number of optical deflection units in the second optical deflection device 200). Therefore, the number of layers of the LCPG can also be reduced. For example, when deflecting at 16 angles, only four layers of LCPG are needed. The LCPG can be made thinner and smaller in size.

[0311] The splicing method of the light source 300 in the above-mentioned light deflection device can be selected as needed.

[0312] Optional, see Figure 8 As shown, multiple light-emitting units can be spliced ​​together along the long axis to form a long beam that conforms to the aspect ratio. This splicing method can form a relatively long and thin beam, and the length direction of the beam is horizontal. This shape of beam is more suitable for scanning methods where the first light deflection device performs one-dimensional deflection in the vertical direction, and then the second light deflection device performs one-dimensional or two-dimensional deflection.

[0313] Optional, see Figure 9As shown, multiple light-emitting units can be spliced ​​together in two rows along the long axis to form a long beam that conforms to the aspect ratio. This splicing method creates a long beam with a width ratio of... Figure 8 The shape shown can be slightly wider. This beam shape is more suitable for scanning methods where the first optical deflector performs one-dimensional deflection in the vertical direction, and then the second optical deflector performs one-dimensional or two-dimensional deflection.

[0314] Optional, see Figure 10 As shown, multiple light-emitting units can be spliced ​​together along their long axis to form a long beam of light that conforms to the aspect ratio. This splicing method can create a relatively slender long beam of light. Figure 8 The difference is that the beam's length direction is vertical. This beam shape is more suitable for scanning methods where the first optical deflector performs one-dimensional deflection in the horizontal direction, and then the second optical deflector performs one-dimensional or two-dimensional deflection.

[0315] Optional, see Figure 11 As shown, multiple light-emitting units can be spliced ​​together in two columns along the long axis to form a long beam of light that conforms to the aspect ratio. This splicing method creates a long beam of light with a width ratio of... Figure 10 The shape shown can be slightly wider. This beam shape is more suitable for scanning methods where the first optical deflector performs one-dimensional deflection in the horizontal direction, and then the second optical deflector performs one-dimensional or two-dimensional deflection.

[0316] Optional, see Figure 12 As shown, multiple light-emitting units can be spliced ​​together along the short axis to form a long strip beam that conforms to the aspect ratio. This splicing method can form a relatively square block beam with small differences in length and width. Relatively speaking, this beam is more suitable for scanning methods where the first optical deflection device performs two-dimensional deflection, and then the second optical deflection device performs one-dimensional or two-dimensional deflection.

[0317] The first optical deflecting device 100 is, for example but not limited to, an acousto-optic deflector (AOD). The AOD can deflect the light beam according to a preset acoustic frequency. The AOD may include an entrance aperture, an acousto-optic crystal, an acoustic generator, and an exit aperture. Depending on the specific configuration, the acousto-optic crystal can achieve quasi-continuous deflection of one-dimensional or two-dimensional light, and the deflection response time is proportional to the width of the light beam within the crystal. The control device 600 is used to apply a driving signal to the acoustic generator of the first optical deflecting device 100, and control the acoustic frequency of the acoustic generator acting on the acousto-optic crystal of the first optical deflecting device 100 through the driving signal, so as to change the deflection angle of the light beam by the first optical deflecting device 100.

[0318] The second optical deflection device 200 is, for example, but not limited to, a liquid crystal polarization grating. By adjusting the arrangement of the liquid crystal molecules in the liquid crystal polarization grating, different second deflection angles can be achieved. The second optical deflection device 200 can deflect the light beam at more than one angle in the first direction, and also at more than one angle in the second direction, for example... Figure 2 and Figure 3 As shown, taking a deflection of 2 angles in the first direction and 8 angles in the second direction as an example, the number of angles deflected in each direction in practical applications can be set as needed. The second optical deflecting device 200 can adopt a partitioned structure or a non-partitioned structure. The liquid crystal material in the liquid crystal layer of the liquid crystal polarization grating is a nematic liquid crystal or a blue phase liquid crystal. When using blue phase liquid crystal, the speed of the second optical deflecting device in adjusting the deflection angle can be further improved, and the time for adjusting the deflection angle can be shortened.

[0319] In some embodiments, the controller 600 includes a first control unit 110 and a second control unit 230;

[0320] The first control unit 110 is used to control the first optical deflection device 100 to deflect multiple different first deflection angles in a deflection cycle, and to incident the beam of each first deflection angle onto the second optical deflection device 200 accordingly.

[0321] The second control unit 230 is used to control the second optical deflection device 200 to receive the light beam and deflect the light beam by the required second deflection angle.

[0322] In the aforementioned optical deflection device, the incident beam of each device varies depending on their positional relationship. For example, excluding the collimating device 400, the incident beam of the first optical deflecting device 100 is the beam emitted by the light source, the incident beam of the polarizing device 500 is the beam deflected by the first optical deflecting device 100, and the incident beam of the second optical deflecting device 200 is the beam amplified by the polarizing device 500. As another example, including the collimating device 400, the incident beam of the collimating device 400 is the beam emitted by the light source, the collimated beam of the first optical deflecting device 100 is the beam collimated by the collimating device, the incident beam of the polarizing device 500 is the beam deflected by the first optical deflecting device 100, and the incident beam of the second optical deflecting device 200 is the beam amplified by the polarizing device 500. Other arrangements follow the same principle.

[0323] The optical deflection device described in this embodiment of the invention increases the number of deflection angles of the beam during the scanning of the entire field of view (FOV), thereby reducing the divergence angle of the beam after deflection. This is because the beam needs to cover the entire FOV angle range after a preset number of deflections. The more deflection angles, the smaller the required divergence angle of the beam. Reducing the divergence angle increases the power of the beam per unit divergence angle, which is beneficial for improving the detection range of the lidar.

[0324] The aforementioned optical deflection device is used in the transmitting module of a lidar system; or the optical deflection device is an optical deflection device in the transmitting module of a lidar system.

[0325] The aforementioned light deflection device can be designed according to specific requirements. When designing different schemes, the aspect ratio of the scanning field of view, the length ratio of the scanning spot reaching the distance, and the splicing method of the light source 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 paths are selected, such as how many collimating lenses and polarizing lenses are used, whether cylindrical or spherical lenses are used, and the positional relationship between each device. This allows the light beam with a certain aspect ratio emitted by the light source to be collimated, and after collimation, the light beam with a relatively small aspect ratio is incident on the first light deflection device 100. The first light deflection device 100 performs fine deflection, and after polarization by the polarizing device 500, it is further coarsely deflected by the second light deflection device 200, thereby covering the required scanning field of view.

[0326] Design Scheme 1:

[0327] Assume the liquid crystal response time of the liquid crystal polarization grating is 5ms. The collimating device 400 uses two cylindrical lenses, F1 and F2; the first optical deflecting device 100 uses an AOD (Alternating Optical Discharge) module; the second optical deflecting device 200 uses a partitioned LCPG (Liquid Crystal Perpendicular Filter) module; and the polarization expanding device 500 uses four cylindrical lenses, F3, F4, F5, and F6. Specifically, in the vertical direction, collimating lens F2 is used for beam collimation, and polarization expanding lenses F3 and F4 are used for beam expansion. In the horizontal direction, collimating lens F1 is used for beam collimation, and polarization expanding lenses F5 and F6 are used for beam expansion.

[0328] The length L from the light source to the second optical deflection device (LCPG module) is calculated by the following formula;

[0329] L = 2*(F1 + F3 + F4) + d;

[0330] F1, F3, and F4 are the focal lengths of lenses F1, F3, and F4, respectively, and d is the length from the back focal plane of lens F4 to the LCPG. The formula for calculating d is:

[0331] d*2*tan(Θv / 2)≥m*{θv 2 *d+Wv 2} 1 / 2 ,

[0332] Where Θv is the vertical deflection angle of the beam after passing through the AOD and the polarizing 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 polarizing lens group. Θv and θv are given by the scanning spot parameters. The formula for calculating Wv is as follows;

[0333] Wv=Wv0*θv0 / θv

[0334] Wv0 and θv0 are the beam waist diameter and divergence angle of the laser beam emitted by the laser source in the vertical direction.

[0335] The total dimensions of the LCPG in the horizontal and vertical directions are respectively

[0336] Lh = d * 2 * tan(Θh / 2)

[0337] Lv = d * 2 * tan(Θv / 2)

[0338] Θh is the horizontal divergence angle of the laser beam incident on the LCPG module.

[0339] While this approach requires a large number of cylindrical lenses, it offers high power per unit field of view (FOV) and relatively low speed requirements for the LCPG. In this approach, the combination of cylindrical lenses F5 and F6, which expand the beam horizontally, may affect the beam divergence vertically. Considering this, cylindrical lenses F5 and F6 can be omitted, but the size of the LCPG module needs to be increased accordingly to receive the entire beam.

[0340] Design Scheme 2:

[0341] Assume the liquid crystal response time of the liquid crystal polarization grating is 5ms. The collimating device uses two cylindrical lenses, F1 and F2; the first optical deflector 100 uses an AOD (Alternating Optical Discharge) module; the second optical deflector 200 uses a partitioned LCPG (Liquid Crystal Polarizing Photoplethysmometer) module; and the polarizing device uses two spherical lenses, F3 and F4. Specifically, in the vertical direction, collimating lens F2 is used for beam collimation, and polarizing lenses F3 and F4 are used for beam polarization. In the horizontal direction, collimating lens F1 is used for beam collimation, and polarizing lenses F3 and F4 are used for beam polarization. The LCPG module has four layers, meaning four optical deflection units achieve 16 separation angles of deflection.

[0342] In the vertical direction: the light emission width V1 of the light source in the vertical direction (first direction), the divergence angle θ1 of the light emission in the vertical direction (first direction), collimated by a cylindrical lens with a focal length of F2, the beam waist diameter V2 of the light beam when it is incident on the first light deflecting device, the divergence angle θ2 of the light beam when it is incident on the first light deflecting device, and the focal length F2 of the collimating lens that collimates the light beam along the first direction satisfy the following relationships: θ2=V1 / F2, 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.

[0343] In the horizontal direction: the emission length H1 of the light source in the horizontal direction (second direction), the divergence angle Θ1 of the light source in the horizontal direction (second direction), collimated by a cylindrical lens with a focal length of F1, the beam waist diameter H2 of the beam when it is incident on the first light deflector in the second direction, the divergence angle Θ2 of the beam when it is incident on the first light deflector in the second direction, and the focal length F1 of the collimating lens that collimates the beam along the second direction satisfy the following relationships: Θ2=H1 / F1, 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 as the focal length F1.

[0344] In some embodiments, when a long, narrow light source is typically selected, H1 >> V1 can be chosen. Correspondingly, since Θ1 ~ θ1, by selecting appropriate lens focal lengths F1 and F2, Θ2 >> θ2 can be achieved, so that the light spot will appear as a long, narrow shape in the far field after passing through a subsequent spherical lens.

[0345] To maximize the amount of light energy that can pass through the AOD, the aperture of the AOD in the vertical direction should preferably be greater than or equal to V2, and the aperture in the horizontal direction should preferably be 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 is approximately parallel in the vertical direction, but still has a large divergence angle in the horizontal direction. Placing the AOD at a distance of twice the focal length F1 from the light source ensures that the aperture of the AOD in the vertical direction can be minimized to V2.

[0346] The AOD is configured to deflect the beam in the vertical direction. In the collimating device 400, the first cylindrical lens strictly collimates the beam in the vertical direction, requiring a divergence angle Θ2 ≤ 0.3°; the second cylindrical lens performs non-strict collimation of the beam in the horizontal direction, and in practice, a divergence angle θ2 ≥ 3° is allowed.

[0347] The light beam exits the AOD and enters the polarizing device 500, where the beam emitted from the AOD is deflected and amplified. This scheme uses a Keplerian lens group as an example, with two polarizing lenses having focal lengths of F3 and F4, and a polarization factor of F3 / F4. If the AOD deflects the beam by ±1.5 degrees, the deflection range after passing through the AOD becomes ±(1.5*F3 / F4) degrees. Simultaneously, the beam divergence angles Θ2 and θ2 are also correspondingly amplified by a factor of F3 / F4. The distance between the AOD and the first polarizing lens F3 is its focal length F3, and the interval between the polarizing lens groups F3 and F4 is F3+F4. After passing through F3 and F4, the beam narrows to its minimum at the rear focal plane of the lens, specifically V3 = V2*F4 / F3 in the vertical direction and H3 = H2*F4 / F3 in the horizontal direction.

[0348] This method eliminates the need for cylindrical lenses, reducing the number of lenses required. It also offers higher power per unit field of view (FOV) and lower speed requirements for the LCPG. Furthermore, using spherical lenses reduces optical distortion compared to cylindrical lenses when magnifying the beam's deflection angle.

[0349] The LCPG module includes at least one LCPG unit, and each LCPG unit includes a liquid crystal half-wave plate and an LCPG plate.

[0350] The thickness of the liquid crystal half-wave plate and LCPG sheet is mainly determined by the thickness of the glass substrate. In practice, the thickness of the glass substrate is generally taken to be << 1mm, and the total thickness of the multilayer liquid crystal is <1mm. In this case, the thickness of the LCPG can be ignored in the optical path design.

[0351] The LCPG chip in this solution can be either a passive LCPG or an active LCPG. The difference between the two is:

[0352] Passive LCPGs do not require the application of voltage during operation. LCPG modules using passive LCPGs only need to apply a corresponding voltage to the liquid crystal half-wave plate to deflect the beam during operation.

[0353] Active LCPGs require the application of corresponding voltages to different deflection angles during operation. LCPG modules using active LCPGs require the application of corresponding voltages to both the liquid crystal half-wave plate and the active LCPG during operation.

[0354] This scheme allows for the placement of LCPG units, which deflect the beam along a deflection direction with a smaller number of deflection angles, earlier in the optical path to improve the diffraction efficiency of the passing beam. However, the beam deflection function can also be achieved without adhering to the above-mentioned order.

[0355] The above are some design examples of optical deflection devices. In practical applications, the optical path design and device selection of optical deflection devices can be designed according to scanning requirements.

[0356] The following describes several typical structures of the optical deflection device of the present invention through specific embodiments.

[0357] Example 2

[0358] The optical deflection device provided in Embodiment 2 of the present invention is shown in the schematic diagram below. Figure 13 As shown, see the 3D structure diagram. Figure 4 As shown, the device includes a collimator 400, a first optical deflector 100, a polarization expander 500, a second optical deflector 200, and a control device 600. In this embodiment, the first optical deflector 100 deflects the light beam one-dimensionally in a first direction, and the second optical deflector 200 deflects the light beam two-dimensionally in both the first and second directions. In this embodiment, the second optical deflector 200 adopts a partitioned structure. Specifically, the first optical deflector 100 deflects the incident light beam sequentially by multiple different first deflection angles in the first direction, and the second optical deflector 200 deflects the light beam by multiple different second deflection angles in both the first and second directions. In this embodiment, the first optical deflector deflects the light beam one-dimensionally, and the second optical deflector deflects the light beam two-dimensionally, which is relatively suitable for situations where the light beam emitted by the light source is a long, narrow beam. In this optical deflection device:

[0359] Light source 300 is used to emit a light beam, the length of which along a first direction is less than the length along a second direction;

[0360] The collimating device 400 is configured to collimate the beam before it enters the first optical deflecting device 100;

[0361] The first optical deflection device 100 is configured to deflect the light beam along a first direction by a plurality of first deflection angles within a deflection cycle;

[0362] The polarization amplification device 500 is disposed between the first optical deflection device and the second optical deflection device, and is configured to amplify the deflection angle of the beam after it is deflected by the first optical deflection device 100 by a preset factor before it is incident on the second optical deflection device 200.

[0363] The second optical deflector 200 is configured to deflect the light beam deflected by the first optical deflector 100 along a first direction and a second direction by a plurality of second deflection angles.

[0364] The controller 600 is used to control the light source 300 to emit a light beam, and to control the first light deflector 100 and the second light deflector 200 to deflect the light beam.

[0365] Collimating device 400 can be a collimating lens, first optical deflecting device 100 can be an AOD (Alternating Optical Discharge) device, polarizing device 500 can be a polarizing lens, and second optical deflecting device 200 can be an LCPG (Liquid Crystal Photoplethysmography) module. The optical path of this device in the first direction (vertical direction) is shown below. Figure 5a As shown, the optical path in the second direction (horizontal direction) is described in [reference needed]. Figure 5b As shown.

[0366] Light source 300 emits a strip-shaped light beam, which is collimated by collimator 400 and then illuminates the first light deflector 100. The width direction of the strip-shaped light beam is the first direction, and the length direction is the second direction. The structure of the light source can be found in [reference needed]. Figure 7 As shown, the light source 300 may include multiple light-emitting units 310.

[0367] The collimating device 400 collimates the beam in both the first and second directions. A light source control unit can control the light source to emit light according to a preset time sequence. The collimation accuracy requirement is higher in the first direction, resulting in a smaller divergence angle of the beam in that direction. This requirement can be achieved through the characteristics of the collimating device. Since the collimated beam size and divergence angle are inversely proportional when the collimating device collimates the beam, a higher collimation accuracy than length can be obtained in the width direction of the strip beam. See also... Figure 5a and Figure 5b As shown, two collimating lenses collimate the light beam in the first and second directions, respectively. The figure uses two cylindrical lenses as an example.

[0368] The first optical deflector 100 deflects the light beam in a first direction and can deflect the light beam by multiple first deflection angles within a preset angle range. The multiple first deflection angles can have a set angular interval. The first optical deflector 100 can deflect the light beam according to a preset timing sequence.

[0369] The light beam deflected by the first optical deflector 100 is then amplified by the polarization expander 500 to increase the deflection angle of the beam in the first and second directions. See also Figure 5a As shown, two polarizing lenses amplify the polarization of the light beam in the first direction. The light beam emitted from the first optical deflecting device 100 is deflected at an increased angle in the first direction after passing through the two polarizing lenses. The amplified light beam is then projected onto the corresponding position of the second optical deflecting device 200. See also... Figure 5b As shown, two polarizing lenses amplify the polarization of the light beam in the second direction. The light beam emitted from the first optical deflection device 100 is deflected at an angle in the first direction after passing through the two polarizing lenses. The amplified light beam is then projected onto the corresponding position of the second optical deflection device 200.

[0370] The second optical deflector 200 deflects the light beam. In this embodiment, the second optical deflector 200 can deflect the light beam at multiple different angles in both the first and second directions. For example, it can deflect the light beam at two angles in the first direction and at eight angles in the second direction.

[0371] The second optical deflection device 200 can adopt a partitioned structure or an unpartitioned structure.

[0372] In this embodiment, the second optical deflection device 200 with a partitioned structure is used as an example. This partitioned structure solves the problem of long waiting times for deflection angle switching and slow angle adjustment when using a liquid crystal polarization grating to deflect the beam in a lidar system, thus affecting the lidar's scanning and detection frame rate. By dividing the second optical deflection device into different deflection partitions, beams with different first deflection angles are amplified and projected onto different deflection partitions of the second optical deflection device 200. Each partition can adjust its deflection angle during its un-illuminated time. The scanning system does not need to wait for the optical deflection device to adjust its state to change the deflection angle, allowing continuous scanning. This avoids the waiting time for angle adjustment, improves the switching speed, and can still meet the detection frame rate requirements even with an increased number of beam deflection angles. This design achieves high frame rate, large field of view, and long-range measurement capability, meeting the needs of applications such as automotive lidar. In this embodiment, the deflection partitions in the second optical deflection device 200 are arranged along the first direction.

[0373] The structure of the second optical deflection device 200 with a partitioned structure is shown in the figure. Figure 14a , 14b As shown in 14c and 14d, the second optical deflection device 200 may include multiple deflection zones 212, each capable of independently adjusting its deflection angle; that is, the deflection angle of the incident beam can be adjusted individually for each deflection zone 212. In the case of a zoned structure:

[0374] The first optical deflecting device 100 is configured to deflect the incident beam at multiple different first deflection angles within a deflection period, corresponding to the incident beam onto the corresponding deflection partition 212 of the second optical deflecting device 200.

[0375] Multiple deflection zones 212 are configured such that the currently scanned deflection zone 212 will deflect the incident beam by the second deflection angle required.

[0376] The controller 600 is used to control the first optical deflector 100 to deflect the incident beam and to control the currently scanned deflection partition 212 in the second optical deflector 200 to deflect the incident beam, and to control at least one currently unscanned deflection partition 212 to adjust its deflection angle to the beam, so that the deflection angle of at least one deflection partition 212 to the incident beam is adjusted to the second deflection angle required for the next deflection cycle after the current deflection cycle is finished being scanned by the incident beam and before the next deflection cycle is started.

[0377] The controller 600 can be used to control the first optical deflector 100 to deflect the incident beam at multiple different first deflection angles within a deflection cycle, corresponding to the incident beams onto the corresponding deflection sections of the second optical deflector 200; it can also be used to control the currently scanned deflection section of the second optical deflector 200 to deflect the incident beam at the required second deflection angle; and it can also be used to control at least one currently unscanned deflection section 212 to adjust its deflection angle to the beam, so that the deflection angle of at least one deflection section 212 to the incident beam is adjusted to the required second deflection angle for the next deflection cycle after the current deflection cycle has ended and before the next deflection cycle begins. Optionally, the controller 600 is specifically used to execute the following control processes in parallel: controlling the currently scanned deflection section of the second optical deflector 200 to deflect the incident beam, and controlling at least one currently unscanned deflection section 212 to adjust its deflection angle to the beam. In other words, while the second optical deflection device 200 deflects the incident beam in the currently scanned deflection partition 212, at least one currently unscanned deflection partition 212 can adjust its deflection angle to the beam under the control of the controller 600.

[0378] Within one deflection cycle, the controller 600 controls the first optical deflector 100 to deflect the beam at multiple different first deflection angles in a time-division manner, corresponding to multiple deflection partitions 212 incident on the second optical deflector 200. The multiple deflection partitions 212 receive and deflect the incident beam in a time-division manner. The deflection cycle is the time required for the multiple deflection partitions 212 to be scanned once by the incident beams at multiple different first deflection angles. Alternatively, the deflection cycle is the time required for the incident beams at multiple different first deflection angles to traverse and scan the multiple deflection partitions 212. In this case, within one deflection cycle, all the multiple incident beams at different first deflection angles will scan all the deflection partitions 212, meaning each deflection partition 212 is scanned and no partition is missed.

[0379] Alternatively, the deflection period is the time required for a specified portion of deflection partitions 212 out of multiple deflection partitions 212 to be scanned once by incident beams at a specified portion of the first deflection angles out of multiple different first deflection angles. In other words, the deflection period is the time required for incident beams at a specified portion of the first deflection angles out of multiple different first deflection angles to traverse and scan the specified portion of deflection partitions 212. Within one deflection period, a portion of the deflection partitions 212 are scanned, meaning that some deflection partitions 212 are missed. The specified portion of deflection partitions 212 can be the same or different in different deflection periods; correspondingly, the specified portion of the first deflection angle incident beams can be the same or different.

[0380] Within each deflection cycle, the controller 600 can control the first optical deflector 100 to generate multiple incident beams with different first deflection angles within a preset angle range and according to a preset deflection time interval, and project them onto the corresponding deflection zones of the second optical deflector 200. Within one deflection cycle, the controller 600 can control the first optical deflector 100 to deflect the incident beams at multiple different first deflection angles in a time-division manner. The multiple incident beams with different first deflection angles are incident into multiple deflection zones in a time-division manner. The multiple deflection zones of the second optical deflector 200 receive the incident beams in a time-division manner and deflect the incident beams. Furthermore, the first optical deflector 100 is configured to incident multiple incident beams with different first deflection angles sequentially onto the corresponding deflection zones of the second optical deflector 200 in a preset order within one deflection cycle; a deflection zone 212 is configured to deflect the incident beam at a corresponding second deflection angle within one deflection cycle.

[0381] The aforementioned second optical deflection device 200 can control at least one deflection partition 212 to complete a second deflection angle adjustment within the scanning interval of two adjacent deflection cycles through the control device 600. This allows at least one deflection partition to be adjusted to the required second deflection angle before the incident beam of the previously scanned deflection partition 212 ends. In other words, the control device 600 can control the beam emitted by the first optical deflection device 100 to be time-divisionally applied to each deflection partition 212. At least one deflection partition 212 will respond in advance to prepare for receiving the incident beam in the next deflection cycle. Before the beam of the next deflection cycle is incident on the deflection partition 212, the deflection angle of the incident beam of the deflection partition 212 has been pre-adjusted to the second deflection angle required for the next deflection cycle. This can reduce the waiting time for angle adjustment to a certain extent, so that at least one incident beam can be irradiated without waiting in the next deflection cycle, thereby improving the scanning frame rate of optical scanning. To further improve the scanning frame rate, optionally, the controller 600 can control each deflection partition 212 to complete a second deflection angle adjustment 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 previous deflection partition 212 ends, so that the incident beam of each first deflection angle can be directly irradiated without waiting, thereby improving the scanning frame rate of optical scanning.

[0382] Within one deflection period, multiple incident beams with different first deflection angles can be sequentially incident onto the corresponding deflection partition 212 in a preset order. The incident order of the multiple incident beams with different first deflection angles can be preset and controlled by the controller 600. Within one deflection period, the multiple different first deflection angles of the incident beams vary from large to small, from small to large, or vary according to a preset random rule in the corresponding deflection direction. Optionally, the incident angles of the multiple incident 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 sequentially. Optionally, the incident angles of the multiple incident 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 sequentially. Optionally, the incident angles of multiple incident beams with different first deflection angles in the optical deflection unit group can also vary according to a preset random rule, such as: randomly varying from -1.5, 1, -0.5, 0, -1.0, 0.5, 1.5. Within different deflection periods, the incident order of the incident beams can be the same or different.

[0383] The aforementioned second optical deflecting device 200 has multiple deflection sections 212 configured such that, within one deflection cycle, the multiple second deflection angles deflecting the incident beam are all the same, all different, or partially the same and partially different. Optionally, within one deflection cycle, the second deflection angle that further deflects the incident beams with multiple first deflection angles can be one, two, or more. For example: within one deflection cycle, multiple deflection sections 212 deflect multiple incident beams with multiple different first deflection angles by 1 degree; in the next cycle, multiple deflection sections 212 deflect multiple incident beams with multiple different first deflection angles by 2 degrees; ... and so on; another example: within one deflection cycle, the first deflection section 212 deflects at least one incident beam with a first deflection angle by 1 degree; the second deflection section 212 deflects at least one incident beam with a first deflection angle by 2 degrees; ... and so on. For example, within one deflection cycle, the first deflection zone 212 deflects the incident beam at least one first deflection angle by 1 degree; the second deflection zone 212 deflects the incident beam at least one first deflection angle by 1 degree; the third deflection zone 212 deflects the incident beam at least one first deflection angle by 3 degrees; the fourth deflection zone 212 deflects the incident beam at least one first deflection angle by 5 degrees; and so on.

[0384] The aforementioned second optical deflection device 200 may have a deflection partition 212 configured to receive an incident beam with at least one first deflection angle. Optionally, a deflection partition 212 may be configured to sequentially receive one, two, or more incident beams with different first deflection angles within one deflection cycle.

[0385] In the aforementioned second optical deflection device 200, the arrangement direction of the multiple deflection partitions 212 is consistent with the scanning direction of the multiple incident beams with different first deflection angles. The multiple deflection partitions 212 can be arranged one-dimensionally along a single direction or in a two-dimensional array. Their arrangement direction can be consistent with the scanning direction of the incident beam at the first deflection angle. For example, if the incident beam scans along a first direction, then the multiple deflection partitions 212 are also arranged along the first direction; if the incident beam performs a two-dimensional array scan, then the multiple deflection partitions are arranged in a two-dimensional array. The scanning method of the incident beam can be related to the shape of the incident beam. In this application, an arrangement along a single direction is used as an example.

[0386] When the incident beam is a strip beam with an aspect ratio greater than a set threshold, the first optical deflector 100 is configured to deflect the incident beam at multiple different first deflection angles along a first direction within one deflection period, so as to perform a one-dimensional scan of the second optical deflector 200, and the multiple deflection partitions 212 included in the second optical deflector 200 are arranged along the first direction of beam deflection; for example Figure 14a , 14bAs shown in 14c and 14d, multiple deflection partitions 212 are arranged vertically. Each deflection partition 212 can be a rectangle with an aspect ratio greater than a set threshold. The width direction of the deflection partition is consistent with the scanning direction of the incident beams at multiple different first deflection angles; that is, the width direction of the deflection partition is along the first direction, and the length direction of the deflection partition is along the second direction.

[0387] In the aforementioned second optical deflection device 200, multiple deflection partitions 212 are configured such that the number of incident beams received by each deflection partition 212 is the same, all different, or partially the same and partially different; correspondingly, the widths of the multiple deflection partitions 212 are the same, all 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, and the width direction of the deflection partition is consistent with the scanning direction of multiple beams with different first deflection angles. The width of each deflection partition 212 is determined according to the number of incident beams received and the width of the incident beams.

[0388] The number of incident beams received by each deflection partition 212 can be configured to be the same. For example, each deflection partition 212 can receive one incident beam, meaning there is a one-to-one correspondence between the incident beams in each deflection partition 212. Alternatively, each deflection partition 212 can receive two or more incident beams, with a one-to-two or one-to-many relationship between the deflection partition 212 and the incident beams. In this case, the width of each deflection partition 212 can be the same, equal to the sum of the widths of the beams it receives. For instance, in a one-to-two configuration, the width of one deflection partition 212 is equal to the sum of the widths of the two beams.

[0389] The number of incident beams received by each deflection partition 212 can be configured to be different. For example, the first deflection partition 212 receives one incident beam, the second deflection partition 212 receives two incident beams, the third deflection partition 212 receives three incident beams, and so on. In this case, the width of each deflection partition 212 is different, and the width of each deflection partition 212 is equal to the sum of the widths of the beams it receives.

[0390] The number of incident beams received by each deflection partition 212 can be configured such that some parts are the same and some parts are different. For example, the first deflection partition 212 receives one incident beam, the second deflection partition 212 receives two incident beams, the third deflection partition 212 receives one incident beam, the fourth deflection partition 212 receives two incident beams, and so on. In this case, the width of each deflection partition 212 is the same in some parts and different in others, and the width of each deflection partition 212 is equal to the sum of the widths of the beams it receives.

[0391] In some optional embodiments, the controller 600 can determine whether the deflection angle of each deflection partition 212 can be adjusted based on its scanning state. Each deflection partition 212 can adjust its deflection angle when it is in a non-scanning state. The controller 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 incident beam deflection of the current deflection cycle and is in a non-scanning state, the controller controls the deflection partition 212 to adjust its deflection angle. Before entering the scanning state in the next deflection cycle, the deflection angle of the deflection partition 212 is adjusted to the second deflection angle required for the next deflection cycle. Each deflection partition 212 can start adjusting its deflection angle after it has completed the deflection of the 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 where there is no incident beam and no beam deflection is required.

[0392] In practical applications, the deflection zone 212 currently being scanned by the beam can be defined as the deflection zone in the scanning state, and the remaining deflection zones 212 can be defined as the deflection zones in the non-scanning state. That is, if a deflection zone is the deflection zone currently being scanned by the incident beam, then the deflection zone is determined to be in the scanning state; otherwise, the deflection zone is determined to be in the non-scanning state.

[0393] Optionally, the deflection partition 212 currently being scanned by the beam and the next deflection partition 212 to be scanned can be determined as deflection partitions in a scanning state, while 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 other than the deflection partition 212 currently being scanned by the beam and the next deflection partition to be scanned. The deflection partition currently being scanned and the next deflection partition to be scanned can be either adjacent in position or not adjacent in position. That is, if a deflection partition 212 is either currently being scanned or will be scanned by the incident beam, then 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 being scanned by the incident beam and the next deflection partition to be scanned can be either adjacent in position or not adjacent in position. The incident beam is usually scanned into each deflection zone 212 in a set order. The controller 600 can determine the next deflection zone to be scanned based on the currently scanned deflection zone and the scanning order.

[0394] Since the incident beam deflected by the first optical deflector 100 can illuminate different positions of the second optical deflector 200, and different positions of the second optical deflector 200 correspond to different deflection zones, it is possible to determine which deflection zones are in a scanning state and which are in a non-scanning state based on the incident position. The control device 600 is specifically used to determine the deflection zone 212 currently in a scanning state and the deflection zone 212 currently in a non-scanning state based on the scanning position of the incident beam on the second optical deflector 200. For the non-scanning deflection zone 212, if its scanning sequence precedes that of the scanning deflection zone 212, it is considered that the deflection zone has completed the beam deflection of the current deflection cycle, and the deflection angle of the deflection zone 212 relative to the beam can be adjusted to the second deflection angle required for the next deflection cycle.

[0395] The deflection angle of each deflection zone in the aforementioned second optical deflecting device 200 can be adjusted by changing the voltage on the electrodes. Different deflecting devices deflect beams using different principles. For optical deflecting devices that change the deflection angle by changing the refractive index, when the second optical deflecting device 200 has a non-partitioned structure, the control device 600 controls the voltage applied to the electrodes of the second optical deflecting device 200 to adjust the refractive index of the medium in the second optical deflecting device 200 relative to the incident beam, thereby adjusting the deflection angle of the second optical deflecting device 200 relative to the incident beam. When the second optical deflecting device 200 has a partitioned structure, the control device 600 controls the voltage applied to the electrodes of each deflection zone 212 to adjust the refractive index of the medium in the deflection zone 212 relative to the incident beam, thereby adjusting the deflection angle of the deflection zone 212 relative to the incident beam.

[0396] For example, when the second optical deflecting 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 optical deflecting device to adjust the arrangement direction of liquid crystal molecules in the liquid crystal polarization grating, thereby changing the second deflection angle of the second optical deflecting device on the incident beam; when the second optical deflecting 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 liquid crystal molecules in the liquid crystal polarization grating, thereby changing the second deflection angle of the deflection partition on the incident beam.

[0397] In some alternative embodiments, see Figure 14a , 14bAs shown in 14c and 14d, the second optical deflection device 200 includes at least one optical deflection unit 210, and each optical deflection unit 210 includes a plurality of deflector partitions 2121; each deflection partition 212 includes a deflector partition 2121 corresponding to a position in the at least one optical deflection unit 210. When the second optical deflection device 200 includes one optical deflection unit 210, the deflection partition is one deflector partition 2121 on this one optical deflection unit 210; when the second optical deflection device 200 includes two optical deflection units 210, the deflection partition includes two deflector partitions 2121 corresponding to positions on these two optical deflection units 210. When the second optical deflection device 200 includes a plurality of optical deflection units 210, the deflection partition 212 includes a plurality of deflector partitions 2121 corresponding to positions on these plurality of optical deflection units 210. The aforementioned 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 14a , 14b Examples 14c and 14d illustrate this using four optical deflection units 210. In practical applications, the number of optical deflection units 210 can be set as needed. Multiple deflection angles can be combined using the deflection angles of each unit 210. For instance, if one optical deflection unit 210 can achieve two angles of deflection, and four angles of deflection are required during light scanning, then two optical deflection units 210 are used; if eight angles of deflection are required, then three optical deflection units 210 are used; if sixteen angles of deflection are required, then four optical deflection units 210 are used; and so on. That is, the relationship between the number of optical deflection units 210 N and the required number of deflection angles M satisfies M = 2. N .

[0398] The optical deflection unit 210 includes deflector sections 2121 whose deflection angles can be independently adjusted. Since the optical deflection unit 210 has multiple deflector sections 2121 whose deflection angles can be independently controlled, beams with different deflection angles can be incident on one of the deflector sections 2121 and deflected. Therefore, the deflection angle of the deflector section 2121 on the beam can be adjusted during the time when it is not scanned. When the second optical deflection device 200 includes at least one optical deflection unit 210, the controller 600 is specifically used to control the voltage on the two electrodes of each deflector section 2121. By changing the voltage on the two electrodes of at least one deflector section 2121, the deflection angle of at least one deflector section on the incident beam is changed, thereby changing the second deflection angle of the corresponding deflection section 212 on the incident beam. In other words, by adjusting the deflection angle of some or all of the multiple deflector sections 2121 on the beam, the second deflection angle of the entire deflection section 212 on the incident beam is changed.

[0399] The aforementioned second optical deflecting device 200 can deflect the incident beam in one direction or in two different directions. When only one direction needs to be deflected, the second optical deflecting device 200 includes at least one optical deflecting unit 210 that deflects the incident beam in the same direction. In this case, the number of optical deflecting units 210 is set according to the number of second deflection angles required, and can be one, two, or more.

[0400] To achieve angular deflection of the light beam in two different directions, the second optical deflection device 200 may include at least two optical deflection units 210, or the second optical deflection device 200 may include at least two optical deflection unit groups 220, each optical deflection unit group 220 including at least one optical deflection unit 210, wherein at least one optical deflection unit group 220 is configured to deflect the light beam in a first direction and at least one optical 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.

[0401] Optionally, the optical deflection unit group 220, which has a smaller number of deflection angles for the beam, is positioned relatively closer to the incident light side. This results in a better deflection effect. For example... Figure 14a , 14b As shown in 14c and 14d, the optical deflection unit group 220 for deflecting in the first direction includes an optical deflection unit 210, placed on the far left, to achieve deflection at two angles in the first direction. See also Figure 5a The diagram shows the optical path of the light deflection device 10 deflecting the light beam along the first direction. The light beam emitted by the light source 300 is collimated by the collimating device 400 and then incident on the first light deflection device 100. After being deflected, the light beam is amplified by the polarizing device 500 and then incident on different deflection zones corresponding to the second light deflection device 200. The second light deflection device 200 can deflect the light beam at two different angles in the first direction. The light deflection unit group 220 for deflecting the light beam in the second direction includes three light deflection units 210, which are placed on the far right to achieve deflection at eight angles in the second direction. See [reference needed]. Figure 5b The diagram shows the optical path of the light deflection device 10 deflecting the light beam along the second direction. The light beam emitted by the light source 300 is collimated by the collimating device 400 and then incident on the first light deflection device 100. After being deflected, the light beam is amplified by the polarizing 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 5bOnly three angles are shown in the diagram. Placing the optical deflection units 210, which deflect the beam along the deflection direction with the fewest deflection angles, earlier in the optical path can improve the diffraction efficiency of the beam. The beam deflection function can also be achieved without following the above-mentioned order.

[0402] The aforementioned second optical deflection device can be used in lidar systems employing all-solid-state scanning. As an optical deflection structure, it enables full-field coverage scanning, thereby increasing detection range and emission power per unit field of view. This second optical deflection device 200 can further deflect the beam emitted from the first optical deflection device 100. The first optical deflection device 100 performs fine deflection, while the second optical deflection device performs coarse deflection. The first optical deflection device can also be an optical phased array (OPA), an acousto-optic deflector (AOD), or an electro-optic deflector (EOD). Since the deflection angle of these devices is only about 2-3 degrees, the second optical deflection device 200 needs to further expand the deflection angle or deflect in different directions to achieve coverage of the field of view. The second optical deflection device 200 can also be a liquid crystal optical deflector.

[0403] In some optional embodiments, the light deflection unit 210 may be, for example but not limited to, a liquid crystal polarization grating. The liquid crystal polarization grating can deflect the outgoing light to a predetermined angle without amplifying the incident light divergence angle; the angle range can reach ± ​​tens of degrees, making it very suitable for expanding the scanning field of view. However, it can only deflect discrete angles and has a slow response speed; therefore, this application employs a partitioned approach for angle switching adjustment. Each light deflection unit 210 can deflect left-handed and right-handed circularly polarized light at two different angles, corresponding to the +1 and -1 diffraction order angles of the liquid crystal grating. By cascading N light deflection units 210, the diffraction of 2... N Light deflection at discrete angles.

[0404] The optical deflection unit 210 includes a liquid crystal half-wave plate 214 and a liquid crystal polarizing grating (LCPG) plate 216; the liquid crystal half-wave plate 214 includes electrodes disposed opposite to each other on both sides and a half-wave plate liquid crystal layer 215 disposed between the electrodes on both sides.

[0405] 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 monolithic electrode 213. Each deflector partition corresponds to at least one first electrode block 211. Each deflector partition 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one first electrode block 211, and a portion on the liquid crystal polarizing grating 216 corresponding to the position of at least one first electrode block 211; or

[0406] Both sides of the liquid crystal half-wave plate 214 include multiple first electrode blocks 211, and two opposing first electrode blocks 211 form a first electrode pair 2110. Each deflector partition 2121 corresponds to at least one first electrode pair 2110. Each deflector partition 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 polarizing grating 216 corresponding to the position of at least one first electrode pair 2110.

[0407] Specifically, the deflection angle of the beam by the corresponding deflector section 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflector section 2121 in the liquid crystal half-wave plate 214.

[0408] In other words, the liquid crystal half-wave plate 214 in the optical deflection unit 210 is equipped with electrodes, which can be divided into blocks on one side or both sides. The liquid crystal polarizing grating 216 can be equipped with electrodes or not. The two cases are described below.

[0409] In some optional embodiments, the liquid crystal polarizing grating 216 is a passive liquid crystal deflection grating without electrodes. The light deflection unit 210 changes the deflection direction of the light beam 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 rotor partition 2121 of the light deflection unit 210 can be realized by dividing one 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, thereby realizing the independent adjustment of the deflection angle of each deflection rotor partition 2121.

[0410] For cases where one electrode is made into a modular structure, see [reference needed]. Figure 14a 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 monolithic electrode 213. Each deflector partition 2121 corresponds to at least one first electrode block 211. Each deflector partition 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of at least one first electrode block, and a portion on the liquid crystal polarizing grating 216 corresponding to the position of at least one first electrode block 211. The portion corresponding to the position refers to the portion that is directly opposite in position. See [reference needed]. Figure 14aAs shown in the dashed box, the portion corresponding to the position of at least one first electrode block 211 refers to the portion on the liquid crystal polarizing grating 216 located within the same dashed box as at least one first electrode block 211. In this case, each first electrode block 211 corresponds to one deflector partition 2121. Alternatively, multiple first electrode blocks 211 may correspond to one deflector partition 2121. Multiple first electrode blocks 211 may include two or more first electrode blocks 211. Multiple first electrode blocks 211 may be arranged in a regular array, such as, but not limited to, a one-dimensional or two-dimensional array arrangement, or they may be arranged in an irregular array arrangement.

[0411] For cases where the electrodes on both sides are made into a block structure, see example... Figure 14b As shown, both sides of the liquid crystal half-wave plate 214 include multiple first electrode blocks 211, and two opposing first electrode blocks form an electrode pair. Each deflector partition 2121 corresponds to at least one electrode pair. Each deflector partition 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 polarizing grating 216 corresponding to the position of at least one electrode pair. The portion corresponding to the position refers to the portion that is directly opposite each other in position. See [reference needed]. Figure 14b As shown in the dashed box, the portion corresponding to the position of at least one electrode pair refers to the portion on the liquid crystal polarizing grating 216 located in the same dashed box as at least one electrode pair. Figure 14b In the liquid crystal half-wave plate 214, the corresponding electrode blocks on both sides are directly opposite each other. However, these corresponding electrode blocks may not be strictly aligned, and a slight misalignment between them is also acceptable. In this case, each electrode pair corresponds to one deflector partition 2121, and alternatively, multiple electrode pairs may correspond to one deflector partition 2121. Multiple electrode pairs may include two or more electrode pairs. The multiple first electrode blocks 211 in each side may be arranged in a regular array, such as, but not limited to, a one-dimensional or two-dimensional array arrangement, or an irregular array arrangement.

[0412] Specifically, the deflection angle of the beam by the corresponding deflector section 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflector section 2121 in the liquid crystal half-wave plate 214.

[0413] In some optional embodiments, the optical deflection unit 210 includes a liquid crystal half-wave plate 214 and a liquid crystal polarizing grating 216. The liquid crystal half-wave plate 214 includes electrodes disposed opposite to each other on both sides and a liquid crystal layer disposed between the electrodes on both sides. The liquid crystal polarizing grating 216 is an active liquid crystal polarizing grating, which includes electrodes disposed opposite to each other on both sides and a grating liquid crystal layer 2164 disposed between the electrodes on both sides. The controller 600 needs to adjust the voltage applied to the electrodes of the liquid crystal half-wave plate 214 and the electrodes of the active liquid crystal polarizing grating 216 to change the deflection angle of the light beam. The deflection rotor partition 2121 of the optical deflection unit 210 can be realized by making one or both sides of the electrodes of the liquid crystal half-wave plate 214 into a block structure and making one or both sides of the electrodes of the liquid crystal polarizing grating into a block structure. The required voltage can be applied to each electrode block, thereby realizing the independent adjustment of the deflection angle of each deflection rotor partition 2121. In the optical 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 polarizing grating 216 further includes a third substrate 2161 and a fourth substrate 2162 disposed opposite to each other.

[0414] The configuration of one side electrode of the liquid crystal polarizing grating 216 as a block structure is similar to that of the liquid crystal half-wave plate 214 described above. Similarly, the configuration of both side electrodes of the liquid crystal polarizing grating 216 as a block structure is also similar to that of the liquid crystal half-wave plate 214 described above, and will not be repeated here. It should be noted that:

[0415] In an optical deflection unit 210, both the liquid crystal polarizing grating 216 and the liquid crystal half-wave plate 214 can be configured as a block structure with one-sided electrodes; see [link / reference] Figure 14c 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 monolithic electrode 213; one side electrode of the liquid crystal polarizing grating 216 includes multiple second electrode blocks 2163, and the other side electrode is a second monolithic electrode 2165; at least one second electrode block 2163 on the liquid crystal polarizing grating 216 and at least one corresponding first electrode block 211 on the liquid crystal half-wave plate 214 form a block group; each deflector partition 2121 corresponds to at least one block group, that is, each deflector partition 2121 corresponds to at least one first electrode block 211 of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode block 2163 of the liquid crystal polarizing grating 216. Each deflector partition 2121 includes a portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and a portion on the liquid crystal polarizing grating 216 corresponding to the position of the block group.

[0416] In a single optical deflection unit 210, both the liquid crystal polarizing grating 216 and the liquid crystal half-wave plate 214 can be configured with block structures using electrodes on both sides, see [link / reference] Figure 14d As shown, the electrodes on both sides of the liquid crystal half-wave plate 214 each include a plurality of first electrode blocks 211, and two opposing first electrode blocks 211 on the liquid crystal half-wave plate 214 form a first electrode pair 2110; the electrodes on both sides of the liquid crystal polarizing grating 216 each include a plurality of second electrode blocks 2163, and two opposing second electrode blocks 2163 on the liquid crystal polarizing grating 216 form a second electrode pair 2160; at least one second electrode pair 2160 on the liquid crystal polarizing grating 216 and at least one first electrode pair 2110 on the liquid crystal half-wave plate 214 form a block group; each deflector partition 2121 corresponds to at least one block group, that is, each deflector partition 2121 corresponds to at least one first electrode pair 2110 of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode pair 2160 of the liquid crystal polarizing grating 216. Each deflector partition 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 polarizing grating plate 216 corresponding to the block group position.

[0417] In one optical deflection unit 210, one side electrode of the liquid crystal polarizing grating 216 can be selected as a block structure, and both sides electrodes of the liquid crystal half-wave plate 214 can be selected as a block structure. Two opposing first electrodes on the liquid crystal half-wave plate form a first electrode pair. At least one second electrode block on the liquid crystal polarizing grating 216 and at least one first electrode pair on the liquid crystal half-wave plate 214 corresponding to a block group are formed. Each deflector partition 2121 corresponds to at least one block group, that is, each deflector partition 2121 corresponds to at least one first electrode pair of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode block of the liquid crystal polarizing grating 216. Each deflector partition 2121 includes the portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and the portion on the liquid crystal polarizing grating 216 corresponding to the position of the block group.

[0418] In one optical deflection unit 210, the two side electrodes of the liquid crystal polarizing grating 216 can be selected as a block structure, and the one side electrode of the liquid crystal half-wave plate 214 can be selected as a block structure. Two opposing second electrodes on the liquid crystal polarizing grating 216 are divided into blocks to form a second electrode pair. At least one second electrode pair on the liquid crystal polarizing grating 216 and at least one first electrode block on the liquid crystal half-wave plate 214 corresponding to a position form a block group. Each deflector partition 2121 corresponds to at least one block group, that is, each deflector partition 2121 corresponds to at least one first electrode block of the liquid crystal half-wave plate 214, and also corresponds to at least one second electrode pair of the liquid crystal polarizing grating 216. Each deflector partition 2121 includes the portion on the liquid crystal half-wave plate 214 corresponding to the position of the block group, and the portion on the liquid crystal polarizing grating 216 corresponding to the position of the block group.

[0419] Specifically, the deflection angle of the beam by the corresponding deflector partition 2121 is adjusted by changing the voltage applied to the electrode corresponding to the deflector partition 2121 in the liquid crystal half-wave plate 214 and the voltage applied to the electrode corresponding to the deflector partition 2121 in the liquid crystal polarizing grating 216.

[0420] It should be noted that, in the case where the second optical deflection device 200 includes at least two optical deflection units 210, the deflection rotor partitions 2121 on the at least two different optical deflection units 210 are respectively arranged correspondingly to each other. In this case, the multiple deflection rotor partitions 2121 that are located at the positions of different optical deflection units 210 and 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 voltage applied to these multiple deflection rotor partitions 2121 respectively.

[0421] From another perspective, the multiple deflector partitions 2121, belonging to different optical deflection units 210 and corresponding to each other, which can form a deflection optical path, can also be understood as a structurally separable deflection partition 212. Each deflection partition 212 has a uniform deflection angle to the light beam and can be independently adjusted as a whole. The multiple deflection partitions 212 are arranged sequentially according to the deflection direction of the light beam at the first deflection angle. That is, a deflection partition includes at least one deflector partition corresponding to a position in an optical deflection unit; the deflector partitions 2121 of at least one optical deflection unit 210 included in a deflection partition 212 can form a deflection optical path. When a deflection partition 212 includes one optical deflection unit 210, the deflector partitions 2121 in this optical deflection unit 210 can form a deflection optical path. When a deflection partition 212 includes two optical deflection units, the deflector partitions 2121 in these two optical deflection units 210 can form a deflection optical path. When a deflection partition 212 includes multiple optical deflection units 210, the deflection rotor partitions 2121 in these multiple optical deflection units can form a deflection optical path.

[0422] Optionally, a quarter-wave plate can be set in front of the first liquid crystal half-wave plate to change the polarization state of the incident beam, so as to change the linearly polarized light emitted by the first light deflection device 100 into circularly polarized light.

[0423] The electrodes, for example but not limited to ITO electrodes, are used. The shape and arrangement of the electrode blocks depend on the shape of the beam to be deflected and its scanning position on the light deflection unit 210. The incident beam is an elongated beam with its length direction along the second direction, and it scans on the light deflection unit 210 along the first direction. Correspondingly, the electrode blocks are also elongated with their length direction along the second direction, and multiple electrode blocks are also arranged in parallel along the first direction. Different electrode blocks are set separately, so voltage can be applied independently to control the arrangement state of the corresponding liquid crystal molecules within the partition.

[0424] 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 some of the liquid crystal half-wave plates 214 belonging to different optical deflection units 210 can be partitioned on both sides, while the electrode structure of others can be partitioned on one side and not partitioned on the other. Similarly, 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 some of the liquid crystal polarization gratings 216 belonging to different optical deflection units 210 can be partitioned on both sides, while the electrode structure of others can be partitioned on one side and not partitioned on the other.

[0425] See Figure 14a , 14b As shown in 14c and 14d, the liquid crystal half-wave plate 214 may further include a first substrate 217 and a second substrate 218 disposed opposite to each other, with electrodes on both sides disposed on the inner surfaces of the first substrate 217 and the second substrate 218 facing each other, and the inner surfaces being, for example, planar. The liquid crystal polarizing grating 216 further includes a third substrate 2161 and a fourth substrate 2162 disposed opposite to each other, with electrodes on both sides disposed on the inner surfaces of the third substrate 2161 and the fourth substrate 2162 facing each other, and the inner surfaces being, for example, planar.

[0426] In some optional embodiments, all the liquid crystal polarization gratings 216 of the optical deflection units 210 in the second optical deflection device 200 are passive liquid crystal polarization gratings, or all the liquid crystal polarization gratings 216 of the optical deflection units 210 in the second optical deflection device 200 are active liquid crystal polarization gratings, or some of the liquid crystal polarization gratings 216 of the optical deflection units 210 in the second optical deflection device 200 are passive liquid crystal polarization gratings and some of the liquid crystal polarization gratings 216 of the optical deflection units 210 are active liquid crystal polarization gratings; the liquid crystal material of the liquid crystal layer may be, for example, but not limited to, nematic liquid crystal or blue phase liquid crystal.

[0427] Taking a passive liquid crystal polarizing grating as an example, the passive liquid crystal polarizing grating does not require an applied voltage to change the liquid crystal arrangement during operation. The polarization state of the passing light beam can be changed by selecting whether or not a voltage is applied to the liquid crystal half-wave plate 214, thereby controlling the deflection direction of the light beam through the passive liquid crystal polarizing grating. The deflection angle of the light beam by the passive liquid crystal polarizing grating is preset. The left-handed and right-handed polarization components of the incident light beam are deflected towards the positive and negative first-order diffraction directions of the liquid crystal polarizing grating. The angles between these two diffraction directions and the incident direction are equal, but the deflection directions are opposite. Therefore, by combining light deflection units with different deflection angles and applying corresponding voltages to the liquid crystal half-wave plate, multiple preset angles of deflection of the passing light beam can be achieved.

[0428] For each incident beam emitted by the first optical deflector 100 at a first deflection angle varying along the first direction, as the beam begins scanning, the voltage applied to the scanned deflection partitions in the second optical deflector 200 is simultaneously and sequentially changed, switching the liquid crystal molecule arrangement of the scanned deflection partitions to the state required by the next beam deflection angle. Thus, each deflection partition 212 can switch its liquid crystal arrangement state by using the gap between other deflection partitions scanned by the first optical deflector 100 along the first direction. When the beam deflected by the first optical deflector 100 has finished scanning the last deflection partition of the second optical deflector 200 within the deflection cycle, the liquid crystal molecule arrangement in the first deflection partition to be scanned in the next deflection cycle has already switched to the state required by the next beam deflection angle. Therefore, the first optical deflector 100 can be immediately controlled to deflect the beam along the first direction to the first deflection partition to be scanned to begin scanning the next deflection cycle without waiting. It can also be understood that the liquid crystal half-wave plate can update the liquid crystal arrangement in real time along the scanning direction of the beam at a preset frequency to achieve seamless switching of the beam deflection angle.

[0429] See Figure 15a The diagram illustrates a structural example of a passive liquid crystal polarizing grating used in the second optical deflector 200. In the second optical deflector 200, the optical deflection units 210 are cascaded in a binary configuration. Multiple optical deflection units are arranged sequentially along the beam propagation direction, and the deflection angles of the passing beam increase progressively in a power of two according to their arrangement. That is, the first optical deflector unit closest to the incident light side has the smallest deflection angle, while the unit farthest from the incident light side has the largest deflection angle. Assuming the deflection angle of the first optical deflector unit is r, the deflection angles of the N optical deflection units 210 arranged sequentially along the beam's exit direction are ±r, ±2r, ±4r, ..., ±2... N-1 r. Correspondingly, the entire second optical deflection device 200, including N optical deflection units, can deflect the passing light beam by 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 on the beam, and the maximum value of the odd multiple is 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 second optical deflection device 200 on the beam are distributed in an arithmetic sequence according to the preset angular interval, and the deflection accuracy of the beam is 2r. The angular interval can be regarded as the angular tolerance of the arithmetic sequence. Therefore, the relationship between the range Ψ of the second deflection angle of the beam on the beam based on the binary cascaded optical deflection unit 210 and the total number M of different deflection angles that can be provided is expressed as:

[0430] Ψ=(2 N -1)·r

[0431] M=2 N

[0432] Where r is the minimum deflection angle of the passing beam among the N optical deflection units, and N is the total number of optical deflection units 210 in the second optical deflection device 200.

[0433] During use, the polarization state of the light beam incident on the passive liquid crystal polarization grating 216 in the light deflection unit 210 can be selected by applying a voltage to the liquid crystal half-wave plate 214 in the light deflection unit 210, thereby controlling the deflection direction of the light beam when it passes through the passive liquid crystal polarization grating 216. For example, if the light beam is deflected in the positive first-order diffraction direction when it passes through the liquid crystal half-wave plate 214 with a saturated voltage applied and then through the passive liquid crystal polarization grating 216, then the light beam will be deflected in the negative first-order diffraction direction when it passes through the liquid crystal half-wave plate 214 without a voltage applied and then through the passive liquid crystal polarization grating 216. Since the polarization state of the light beam is 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, the voltage applied to the liquid crystal half-wave plate 214 in the next light deflection unit 210 needs to be turned off so that the liquid crystal half-wave plate 214 can change the polarization state of the 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, a saturation voltage needs to be applied to the liquid crystal half-wave plate 214 in the next light deflection unit 210 so that the polarization state of the light beam is not changed.

[0434] Figure 15bThis diagram illustrates 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 light beam. The shaded area indicates 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 light beam. The white area indicates that the saturation voltage applied to the liquid crystal half-wave plate 214 is turned off, and the corresponding liquid crystal half-wave plate 214 will change the polarization state of the light beam. Since all liquid crystal polarization gratings are passive, no voltage can be applied to any of the passive liquid crystal polarization gratings 216; they will deflect the light beam by a preset angle in the direction corresponding to the positive or negative diffraction order, depending on the polarization state of the light beam. Figure 15b The example illustrates a second optical deflection device comprising four cascaded optical deflection units in a binary configuration. Each optical deflection unit includes a liquid crystal half-wave plate and a passive liquid crystal polarization grating. The units are arranged sequentially along the beam emission direction: the first unit includes a liquid crystal half-wave plate I and a passive liquid crystal polarization grating I; the second unit includes a liquid crystal half-wave plate II and a passive liquid crystal polarization grating II; the third unit includes a liquid crystal half-wave plate III and a passive liquid crystal polarization grating III; and the fourth unit includes a liquid crystal half-wave plate IV and a passive liquid crystal polarization grating IV. Furthermore, the passive liquid crystal polarization gratings I-IV have the same grating vector direction. The deflection angle of the beam by the passive liquid crystal polarization gratings I-IV increases sequentially in power of 2, with the value being the optical deflection unit number minus one, corresponding to r, 2r, 4r, and 8r. In practical applications, the deflection angle of each liquid crystal polarization grating can be selected as needed.

[0435] See Figure 15a and Figure 15bAs shown, a reference frame is established with a horizontally incident beam as 0 degrees, a leftward deflection as a positive angle, and a rightward deflection as a negative angle. If the polarization state of the beam when it enters the second optical deflector 200 causes the passive liquid crystal polarizing grating to deflect the beam in the direction of positive first-order diffraction, and the beam wants to obtain a +r deflection angle after passing through the entire second optical deflector, the voltage to the liquid crystal half-wave plate I must be turned off. This causes the beam passing through the liquid crystal half-wave plate I to change its polarization state first. In this way, the passive liquid crystal polarizing grating I will deflect the passing beam by -r and simultaneously change the polarization state of the beam back to its incident polarization state. Since the passive liquid crystal polarizing gratings II and III are then required to continue deflecting the beam in the directions of -2r and -4r respectively, the voltages of the liquid crystal half-wave plates II and III must be turned off accordingly so that the beam changes its polarization state before entering the corresponding passive liquid crystal polarizing gratings II and 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 polarizing grating III, returning it to its incident polarization state. This allows the light beam to be deflected back to +8r in the opposite direction when passing through the passive plate IV, ultimately obtaining the deflection direction r. Similarly, the second optical deflection device 200 can also be deflected in the same way... Figure 15b The voltage application method shown deflects the passing light beam to other preset deflection angles, such as 3r, 5r, 7r, 9r, 11r, 13r, 15r, -r, -3r, -5r, -7r, -9r, -11r, -13r, and -15r in the figure. By changing the voltage application of the liquid crystal half-wave plates I-IV, the polarization state of the light beam before entering the corresponding passive liquid crystal polarization grating I-IV is adjusted. Through the cooperation of the four optical deflection units 210, 16 different deflection angles can be achieved. It can be understood that different numbers of deflection angles can be achieved by setting different numbers of optical deflection units 210.

[0436] Figure 15c This is a schematic diagram showing the relationship between the voltage control of the binary cascaded optical deflection unit 210 and the deflection angle for two-dimensional deflection of the light beam. Figure 15b The difference is that, Figure 15b The four deflection units in the middle deflect the beam in the same direction, such as horizontal or vertical. Figure 15c In the middle section, one of the four deflection units deflects the beam in the first direction, and the other three deflection units deflect the beam in the second direction. Here, p represents the minimum deflection angle of the beam in the vertical direction, and h represents the minimum deflection angle of the beam in the horizontal direction. The four deflection units working together can achieve two deflection angles in the vertical direction and eight deflection angles in the horizontal direction. For example... Figure 15cThe angles shown 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).

[0437] The difference between using an active liquid crystal polarizing grating and a passive liquid crystal polarizing grating is that a passive grating does not require an applied voltage during operation. Beam deflection is achieved simply by applying a corresponding voltage to the liquid crystal half-wave plate, resulting in fast response and a simple driving program. An active grating, on the other hand, requires applying a corresponding voltage for different deflection angles. This necessitates adjusting the applied voltages to both the liquid crystal half-wave plate and the active grating separately for each deflection angle. When using an active grating, the applied voltages to both the liquid crystal half-wave plate and the active grating in the optical deflection unit 210 of the second optical deflection device can be changed. By altering the applied voltage, different deflection angles can be achieved; further details are omitted here.

[0438] In some optional embodiments, in the second optical deflection device 200 described above, the adjustment time for the second deflection angle of the incident beam by the deflection partition adjustment is no greater than the time interval between two adjacent deflection cycles of the deflection partition being scanned by the incident beam. To ensure that each deflection partition has sufficient time for deflection angle adjustment, the number of deflection partitions can be reasonably set within the duration of the deflection cycle. This is because if the number of deflection partitions is too small, it cannot be guaranteed that the time interval between two adjacent deflection cycles of each deflection partition being scanned by the incident beam is sufficient to complete the deflection angle adjustment. Therefore, the number of deflection partitions 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 multiple beams with multiple different first deflection angles to multiple different second deflection angles, and the adjustment time required for the second optical deflection device 200 to complete one deflection angle adjustment. Alternatively, the number of deflection partitions can be set based on the number of deflection angles of the second optical deflection device, the required frame rate, and the time required for the second optical deflection device to complete one deflection angle adjustment. This ensures that, while meeting the required frame rate, the deflection partitions can complete the deflection angle adjustment within the interval between two scans. Specifically, the number D of deflection partitions 212 is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second optical deflection device 200, F is the frame rate at which the second optical deflection device 200 completes one round of deflection of M angles, and T is the time required for the second optical deflection device 200 to complete one deflection angle adjustment. Setting the number of deflection partitions according to this formula is a preferred method, ensuring that each deflection partition does not need to wait and can complete the angle adjustment during the scan interval. Even setting a smaller number can still reduce waiting time to some extent.

[0439] The response speed of the liquid crystal half-wave plate 214 is on the order of milliseconds. The system is inactive during the adjustment of the liquid crystal switching state. To meet the requirement of a 10Hz frame rate for optical scanning, a single pass through all scanning angles must be completed within 100ms. Therefore, to ensure system scanning efficiency, either the ITO electrode layer of the liquid crystal half-wave plate or both the liquid crystal half-wave plate and the liquid crystal polarizing grating are segmented. During beam scanning, the beam is incident on one electrode segment, while the remaining electrode segments not incident on the beam can be adjusted to change the phase delay.

[0440] Taking the first light deflection device 100 deflecting the emitted light beam in the vertical direction as an example. Assuming the liquid crystal response time is 5s, the combination of N light deflection units needs to achieve a total deflection of multiple discrete angles. Therefore, each light deflection unit needs to be divided into D deflection zones along the vertical direction. See [link / reference] Figure 16 , Figure 17 , Figure 18As shown, at the beginning of a frame (100ms in duration), the light beam enters the first deflection zone, and the beam width in the vertical direction is designed to be the width of one deflection zone. The first light deflecting device 100 deflects the beam quasi-continuously downwards at a downward angle, and the beam begins to enter the second deflection zone. At this time, the first and second deflection zones are in a "scanning" state, and the state of the liquid crystal molecules within them cannot be adjusted, while the remaining K-2 layers are in a "non-scanning" state. When the beam leaves the first deflection zone and begins to enter the third deflection zone, the first deflection zone enters a "non-scanning" state, while the second and third deflection zones are in a "scanning" state. According to the above rules, when the beam enters the Dth deflection zone, one deflection cycle is completed. At this time, the first light deflecting device 100 deflects the beam back into the first deflection zone, and the second deflection cycle begins. Multiple deflection cycles are required within one frame, and in each deflection cycle, the second light deflecting device 200 deflects the light to one of multiple discrete angles.

[0441] See Figure 16 , Figure 17 , Figure 18 As shown, in some embodiments, the light deflection unit 210 is divided into 1-D parallel deflection partitions. Corresponding to each second deflection angle, incident light beams at different first deflection angles scan vertically from the first partition to the Dth deflection partition. After the light beam deflected by the first light deflection device 100 leaves the first deflection partition and scans the second deflection partition, the first deflection partition, which has already been scanned, can begin to change the voltage applied to it through corresponding independently configured ITO electrode blocks, thereby switching the liquid crystal molecule arrangement state corresponding to the first deflection partition to the liquid crystal molecule arrangement state required for the next second deflection angle. In other words, during the process of the incident light beam scanning from the second deflection partition to the Dth deflection partition, the liquid crystal molecule arrangement state corresponding to the first deflection partition can be synchronously changed through the corresponding ITO electrode blocks, and the entire process is sufficient to complete the change of the liquid crystal molecule arrangement state of the first deflection partition. Therefore, for a second deflection angle, when the incident beam at the first deflection angle has scanned from the first deflection partition to the Dth deflection partition, and some liquid crystal molecules corresponding to the first deflection partition have completed the state change required for the next second deflection angle, the incident beam can immediately and seamlessly start scanning the next second deflection angle again from the first deflection partition.

[0442] For example, to meet a scan frame rate of 10Hz, for Figure 2 and Figure 3All 16 second deflection angles need to be scanned within 100ms. The scanning time for each second deflection angle is 100 / 16 = 6.25ms. The optical deflection unit is divided into 10 deflection zones, so the scanning time for each deflection zone is 6.25 / 10 = 0.625ms. As mentioned above, the liquid crystal state of the deflection zone cannot be changed during the scanning of the current deflection zone and the next deflection zone. Therefore, for a deflection zone, the time to adjust the deflection angle is 6.25 - 2 * 0.625 = 5ms. This time is equal to the adjustment time of the liquid crystal state during the switching of the next deflection angle. Therefore, 5ms is sufficient to meet the requirement of seamless switching of deflection angles.

[0443] The above description assumes that the beam scans each deflection zone sequentially from top to bottom within one deflection cycle, and then continues to scan each deflection zone sequentially from top to bottom in the next deflection cycle. In practical applications, the scanning order does not need to be followed; the scanning order can be randomly adjusted. For example, the beam may not be incident in a top-to-bottom order. Furthermore, within one deflection cycle, the second deflection angle of each beam can be the same or different, as long as it ultimately covers the entire field of view.

[0444] In the aforementioned second optical deflection device 200, the optical deflection unit is divided into D deflection rotor 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. Correspondingly, the size of the optical deflection unit in the second direction must satisfy the requirement of including the size of the light beam in the second direction.

[0445] The second optical deflection device 200 described above can be any suitable device besides an LCPG capable of coarse beam deflection, as long as it is divided into multiple deflection zones 212 and the deflection angle of each zone can be adjusted individually. This invention is consistent with the concept of this application. The second optical deflection device 200 is typically thin; therefore, when the incident beam enters the device, the beam path is not affected by the thickness of the device, allowing for approximately straight-line illumination.

[0446] In some optional embodiments, the second optical deflecting device 200 further includes a temperature regulator 240 configured to change the time it takes for the second optical deflecting device 200 to adjust its deflection angle by changing its temperature. To ensure the proper functioning of the liquid crystal molecules within the liquid crystal polarizing grating of the second optical deflecting device, the temperature of the second optical deflecting device 200 needs to be controlled within a certain temperature range. The temperature regulator can control the temperature of the second optical deflecting device 200 within a preset temperature range. Furthermore, the speed at which liquid crystal molecules adjust their state differs at different temperatures, resulting in different adjustment times for each deflection zone. Therefore, the adjustment time for the deflection angle of each deflection zone can be changed by altering the temperature of the second optical deflecting device 200.

[0447] The aforementioned second optical deflection device 200 with a partitioned structure can, during the change in incident position caused by the change in the first deflection angle of the incident beam, synchronously refresh the liquid crystal molecule arrangement of the scanned deflection partitions to the state required for the next second deflection angle by applying a voltage change. This allows for seamless switching of the beam deflection angle without waiting. For existing LCPG modules, since a uniform voltage is applied to the entire ITO electrode on the liquid crystal half-wave plate, when the LCPG module needs to switch the deflection angle of the beam, it needs to correspondingly change the voltage applied to the ITO electrode of the liquid crystal half-wave plate. This process requires waiting for the change in the liquid crystal molecule arrangement state, which takes a long time. Therefore, in existing LCPG modules, the entire system can only wait and cannot scan and detect during the aforementioned deflection angle switching process.

[0448] In some optional embodiments, the incident beam can be a strip beam. The second light deflector 200 is configured such that, when the incident beam is a strip beam: multiple incident beams with different first deflection angles are deflected to the same second deflection angle to complete scanning of a corresponding scanning partition of the field of view; and each beam with a different first deflection angle is deflected to multiple different second deflection angles to complete scanning of multiple scanning partitions corresponding to different second deflection angles. The scanning partition is rectangular, and the length of the beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition.

[0449] It is understood that, in some embodiments, when scanning the entire field of view, the angle and order of the beams with the first and second deflection angles can be configured to complete the scanning of one scanning area first, then proceed to the next scanning area, and so on, until all scanning areas are scanned. That is, within one deflection cycle, multiple incident beams with different first deflection angles can be deflected to the same second deflection angle to complete the scanning of a corresponding scanning partition of the field of view; different deflection cycles deflect the incident beams with different first deflection angles at different second deflection angles, thus completing the scanning of a corresponding scanning partition within one deflection cycle; after completing one scanning partition, the next deflection cycle scans the next scanning partition; thus, multiple different scanning partitions can be scanned correspondingly through multiple deflection cycles.

[0450] See Figure 2 As shown, the entire field of view can be divided into multiple scanning zones. Figure 2 Taking 16 scanning zones as an example, corresponding to 16 grids in the diagram. The second optical deflector 200, with different deflection zones, deflects the received strip-shaped incident light at different second deflection angles, illuminating different scanning zones. One second deflection angle corresponds to one scanning zone. Multiple incident beams with first deflection angles, after being deflected by the second deflection angle, can completely cover a scanning zone. Therefore, 16 second deflection angles can correspond to 16 scanning zones. See also... Figure 2 As shown, by deflecting two second deflection angles in the first direction and eight second deflection angles in the second direction, it is possible to achieve... Figure 2 The scanning of the 16 scanning partitions shown corresponds to a second deflection angle. That is, multiple different first deflection angles deflected by the first optical deflector 100 are deflected by the second optical deflector 200 to the same second deflection angle, thus covering one scanning partition. 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. In actual scanning, within the first deflection cycle, beams with multiple first deflection angles are all deflected by the first second deflection angle to complete the scanning of the first square in the first row; within the second deflection cycle, beams with multiple first deflection angles are all deflected by the second second deflection angle to complete the scanning of the second square in the first row; ...; within the fourth deflection cycle, beams with multiple first deflection angles are all deflected by the fourth second deflection angle, such as... Figure 2 The scan of the fourth square in the first row is completed; and so on, after 16 deflection cycles, the scan of all the scan partitions corresponding to the 16 squares is completed.

[0451] In some other embodiments, the second optical deflecting device 200 deflects incident beams with multiple different first deflection angles to one of multiple different second deflection angles within one deflection cycle, respectively scanning a portion of the corresponding scanning partition. Within one deflection cycle, the second deflection angles of the incident beams with multiple different first deflection angles may be the same or different; the second deflection angles of the incident beams with each first deflection angle are different in different deflection cycles. Within one deflection cycle, each incident beam with multiple different first deflection angles is randomly deflected to one of multiple different second deflection angles, such that the second deflection angles of all incident beams with first deflection angles within one deflection cycle are the same, partially the same, partially different, or completely different from each other. Optionally, within one deflection cycle, at least two incident beams with multiple different first deflection angles are deflected to different second deflection angles, such that the second deflection angles of all incident beams with first deflection angles within one deflection cycle are partially the same, partially different, or completely different from each other.

[0452] For example, within one deflection cycle, deflected beams incident at different first deflection angles can be deflected at two or more different second deflection angles. In this case, within one deflection cycle, instead of focusing on scanning a single corresponding scan partition, the beams are scanned at different positions along the first deflection angle within two or more different scan partitions in a skipping manner. After multiple deflection cycles, scanning of all scan partitions can be completed. For example, in this embodiment, within one deflection cycle, the scanned positions of the beams formed after deflection at the second deflection angle and the scan partitions corresponding to different second deflection angles are far apart, which can reduce crosstalk between adjacent scans.

[0453] See Figure 3As shown, the entire field of view can be divided into multiple scanning zones, with 16 scanning zones corresponding to the 16 grids in the diagram. Within one deflection cycle, the second optical deflector 200 can deflect beams with multiple first deflection angles to different second deflection angles, so as to alternately scan different scanning zones. For example, within the first deflection cycle, the second optical deflector 200 deflects a beam with a first first deflection angle to a first second deflection angle, scanning a small strip area in the first square of the first row; deflects a beam with a second first deflection angle to a second second deflection angle, scanning a small strip area in the second square of the first row; and so on. Within the second deflection cycle, the second optical deflector 200 deflects a beam with a first first deflection angle to a first second deflection angle, scanning a small strip area in the second square of the first row; deflects a beam with a second first deflection angle to a second second deflection angle, scanning a small strip area in the third square of the first row; and so on. By repeating this process, the scanning area corresponding to each square is scanned crosswise. After multiple deflection cycles, the scanning of all scanning partitions corresponding to all squares is completed. This configuration allows the two scanning areas corresponding to each other within the field of view to be relatively far apart in two adjacent deflection cycles. Consequently, the photosensitive pixels used by the receiving module to sense these two corresponding scanning areas are also relatively far apart during these two adjacent scanning periods, reducing crosstalk between these photosensitive pixels that operate sequentially.

[0454] Compared to scanning with a circular or near-circular light spot, using a long beam to scan the field of view and deflecting the beam in the width direction with a first light deflector (e.g., AOD) allows for a significant reduction in the number of angles the second light deflector (e.g., LCPG) deflects in the first and second directions. Figure 2 and Figure 3 As shown, the second optical deflection device 200 deflects 16 angles, 8 angles in the horizontal direction and 2 angles in the vertical direction. The number of angles deflected by the second optical deflection device 200 is related to the number of layers it contains (i.e. the number of optical deflection units in the optical deflection device). Therefore, the number of layers of the second optical deflection device 200 can also be reduced. For example, when deflecting 16 angles, the second optical deflection device 200 only needs four layers. The second optical deflection device 200 can be made thinner and smaller in size.

[0455] The scanning partition is rectangular. The length of the strip beam after being deflected by the second deflection angle is equal to the length of one direction of the scanning partition, for example... Figure 2 and Figure 3The length of the strip beam after being deflected by the second deflection angle is equal to the length of the scanning partition in the second direction. The long side of the strip beam emitted from the first optical deflector 100 is perpendicular to the optical deflection direction of the first optical deflector 100, which means that compared to the blocky scanning light, the beam deflected by the second deflection angle can cover a larger field of view at the same total power. Therefore, the second optical deflector 200 can cover a larger overall field of view by deflecting fewer different angles. This results in fewer layers of the second optical deflector 200 (i.e., fewer optical deflection units 210), lower cost, and faster response speed.

[0456] The aforementioned optical deflection device 10 can be applied in the field of depth sensing technology, such as, but not limited to, in lidar systems employing all-solid-state scanning, to achieve full-field-of-view coverage scanning as an optical deflection structure, thereby increasing detection range and emission power per unit field of view. It can also be used in high-speed photography, optical engineering, space optical communication, non-destructive testing, optical sensing technology, optical multimode guidance technology, magneto-optical recording technology, magneto-optical imaging technology, laser display technology, and precision optical instruments. The second optical deflection device 200 in the optical deflection device 10 can further deflect the beam emitted from the first optical deflection device 100; the first optical deflection device 100 performs fine deflection of the beam, while the second optical deflection device 200 performs coarse deflection. The first optical deflector 100 can also be an optical phased array (OPA), an acousto-optic deflector (AOD), or an electro-optic deflector (EOD). Since the deflection angle of these devices is only about 2-3 degrees, the second optical deflector 200 is needed to further expand the deflection angle or deflect in different directions to achieve coverage of the field of view. The second optical deflector 200 can be a liquid crystal optical deflector.

[0457] In some optional embodiments, the control device 600 of the above-described optical deflection device 10 can be an independent device, enabling control of the first optical deflection device 100 and the second optical deflection device 200 through a single independent device. The control device 600 can also be a discrete device, see [reference needed]. Figure 4 As shown, it includes a first control unit 110 and a second control unit 230;

[0458] The first control unit 110 is used to control the first optical deflection device 100 to deflect multiple different first deflection angles in a deflection cycle, and to project the incident beam of each first deflection angle onto the corresponding deflection zone of the second optical deflection device 200. The first control unit 110 can be set up separately or integrated with the first optical deflection device.

[0459] The second control unit 230 is used to control multiple deflection sections 212 to receive the incident light beam in a time-division manner and to deflect the incident light beam by the required second deflection angle, and to control the deflection sections 212 to pre-adjust their deflection angles to the light beam before being scanned by the incident light beam; wherein, the deflection angle of at least one deflection section 212 to the incident light beam is adjusted to the required second deflection angle for the next deflection cycle after the current deflection cycle has been scanned by the incident light beam and before the next deflection cycle begins to be scanned by the incident light beam. The second control unit 230 can be set independently or integrated with the second optical deflection device.

[0460] In some optional embodiments, the device further includes a temperature regulator 240 configured to change the time it takes for the second optical deflector 200 to adjust its deflection angle by changing the temperature of the second optical deflector 200. The temperature regulator 240 may be provided separately or integrated with the second optical deflector.

[0461] The aforementioned light deflection device with a partitioned structure can, during the change in incident position caused by the change in the first deflection angle of the incident beam, synchronously refresh the liquid crystal molecule arrangement of the scanned deflection partitions to the state required for the next second deflection angle by applying a change in voltage. This allows for seamless switching of the beam deflection angle without waiting. For existing LCPG modules, since a uniform voltage is applied to the entire ITO electrode on the liquid crystal half-wave plate, when the LCPG module needs to switch the deflection angle of the beam, the voltage applied to the ITO electrode of the liquid crystal half-wave plate needs to be changed accordingly. This process requires waiting for the change in the liquid crystal molecule arrangement state, which is time-consuming. Therefore, in existing LCPG modules, the entire system can only wait and cannot scan or detect during the aforementioned deflection angle switching process.

[0462] In this embodiment, when the second optical deflection device adopts a partitioned structure, a polarization amplification device is set between the first and second optical deflection devices to amplify the deflection angle of the beam deflected by the first optical deflection device. This allows adjacent beams deflected by the first optical deflection device to be separated within the shortest possible distance, illuminating different deflection partitions. This shortens the distance between the second and first optical deflection devices, making the overall structure of the optical deflection device smaller. By reducing the distance between the two stages of optical deflection devices through the polarization amplification device, the spot of the beam illuminating the second optical deflection device after deflection by the first optical deflection device becomes smaller as the distance decreases. The size of the second optical deflection device can also be smaller, further reducing the overall structure of the optical deflection device. This meets the miniaturization requirements of automotive LiDAR in applications such as intelligent driving. Furthermore, the cooperation of the two stages of optical deflection devices and the polarization amplification device allows for continuous and precise adjustment of the beam deflection angle within a wider angle range. It also allows for a smaller angle interval between the beams deflected by the first optical deflection device, achieving more precise optical scanning and improving the coverage effect of the LiDAR optical scanning.

[0463] Example 3

[0464] The optical deflection device provided in Embodiment 3 of the present invention is shown in the schematic diagram below. Figure 19 As shown. The difference from the optical deflection device provided in Embodiment 2 is that in this embodiment, the first optical deflection device 100 can deflect the light beam in two dimensions. Specifically, the first optical deflection device deflects the incident light beam sequentially in at least one of the first and second directions by multiple different first deflection angles, and the second optical deflection device deflects the expanded light beam in the first and second directions by multiple different second deflection angles.

[0465] In this embodiment, the first optical deflection device deflects the light beam in two dimensions, and the second optical deflection device deflects the light beam in two dimensions, which is relatively suitable for situations where the light beam emitted by the light source is not a long strip beam.

[0466] In Embodiment 2, when the first optical deflection device 100 deflects the light beam in one dimension, a strip beam is selected. Taking a scanning partition as an example, multiple strip beams with first deflection angles can be deflected to the same second deflection angle to cover a deflection partition.

[0467] In this third embodiment, the first optical deflection device 100 deflects the light beam in two dimensions. The light beam can be square, approximately square, or circular. An approximately square light beam refers to a light beam whose length and width difference is not greater than a preset difference.

[0468] When the first optical deflector deflects the light beam, the distribution of the multiple beams deflected at different first deflection angles can be found in [reference needed]. Figure 20As shown, the beam deflected each time corresponds to Figure 20 A small square in the middle, scanning multiple small squares in the first and second directions can cover a scanning area. Figure 20 The example shows the entire area. Completing scans of multiple areas can cover the entire field of view.

[0469] When the first optical deflection device 100 achieves two-dimensional deflection, it can be achieved by two optical deflection devices (AODs) working together. One AOD achieves deflection in the first direction, and the other AOD achieves deflection in the second direction.

[0470] The partitioning method of the second optical deflection device 200 can adopt the partitioning method in Embodiment 2. In this case, Figure 20 The beams corresponding to the small squares in the first row are all incident into a deflection zone, and the deflection zone can adjust the deflection angle when there is no beam incident.

[0471] The second optical deflection device 200 can also be divided into sections other than those in Embodiment 2, but in both the first and second directions, with the distribution of the deflection sections similar to... Figure 20 As shown in the image. At this time. Figure 20 The beams corresponding to the first small square are all incident on a deflection zone, and the deflection zone can adjust its deflection angle when there are no beams incident on it. Optionally, beams corresponding to multiple small squares can also be incident on a deflection zone; for example, beams corresponding to every 4 or 9 small squares can be grouped together, and each group of beams can be incident on a deflection zone.

[0472] Example 4

[0473] The optical deflection device provided in Embodiment 4 of the present invention is shown in the schematic diagram below. Figure 21 As shown. The difference between this embodiment and the optical deflection device provided in Embodiment 2 is that in this Embodiment 4, the second optical deflection device 200 does not employ a partitioned structure. In this case, the beam deflected by the first optical deflection device 100 is amplified by the polarization amplification device 500 and then 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 multiple beams deflected by the first optical deflection device in the first direction at multiple first deflection angles generally have the same second deflection angle to avoid waiting time for angle switching. One deflection cycle corresponds to completing the scanning of one scanning area; the next deflection cycle continues to complete the scanning of the next scanning area. Before the start of the next deflection cycle, a certain amount of time may be needed to adjust the deflection angle after one deflection cycle is completed.

[0474] In this embodiment, the first optical deflection device deflects the light beam in one dimension, and the second optical deflection device deflects the light beam in two dimensions, which is relatively suitable for situations where the light beam emitted by the light source is a long strip beam.

[0475] Optionally, in order to reduce the waiting time for deflection angle adjustment in this fourth embodiment, the temperature of the second optical 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 correspondingly faster speed can be used to speed up the angle switching time.

[0476] Example 5

[0477] The optical deflection device provided in Embodiment 5 of the present invention is shown in the schematic diagram below. Figure 22 As shown. The difference between this embodiment and the optical deflection device provided in Embodiment 3 is that in this Embodiment 5, the second optical deflection device 200 does not employ a partitioned structure. In this case, the beam deflected by the first optical deflection device 100 is amplified by the polarization amplification device 500 and then 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 multiple beams deflected by the first optical deflection device in the first and second directions at multiple first deflection angles are all deflected at the same second deflection angle. One deflection cycle corresponds to completing the scanning of one scanning area; the next deflection cycle continues to complete the scanning of the next scanning area. Before the start of the next deflection cycle, a certain amount of time may be needed to adjust the deflection angle.

[0478] In this embodiment, the first optical deflection device deflects the light beam in two dimensions, and the second optical deflection device deflects the light beam in two dimensions, which is relatively suitable for situations where the light beam emitted by the light source is not a long strip beam.

[0479] Example 6

[0480] The optical deflection device provided in Embodiment Six of the present invention is shown in the schematic diagram below. Figure 23 As shown. The difference between this embodiment and the optical deflection devices provided in Embodiments 3 and 5 is that in this embodiment, the first optical deflection device 100 can deflect the light beam in two dimensions, while the second optical deflection device 200 only deflects the light beam in one dimension. Specifically, the first optical deflection device sequentially deflects the incident light beam at least in one of the first and second directions by multiple different first deflection angles, and the second optical deflection device deflects the polarized light in either the first or second direction by multiple different second deflection angles.

[0481] In this embodiment, the first optical deflection device deflects the light beam in two dimensions, and the second optical deflection device deflects the light beam in one dimension, which is relatively suitable for situations where the light beam emitted by the light source is not a long strip beam.

[0482] When the first optical deflection device 100 achieves two-dimensional deflection, it can be achieved by two optical deflection devices (AODs), one of which achieves deflection in the first direction and the other achieves deflection in the second direction.

[0483] The second optical deflection device 200 can adopt either a partitioned structure or a non-partitioned structure. The case where the second optical deflection device 200 adopts a partitioned structure is similar to that in Embodiment 3, and the case where the second optical deflection device adopts a non-partitioned structure is similar to that in Embodiment 5.

[0484] See Figure 2 and Figure 3 As shown, when the second optical deflecting device 200 deflects the light beam in one dimension, it can deflect the beam at multiple second deflection angles in the second direction, such as eight second deflection angles, corresponding to the scanning of a row of eight scanning zones. Of course, in order to complete the scanning of the entire field of view, the deflection angle range of the first optical deflecting device 100 in the first direction and the size of the second optical deflecting device in the first direction can be increased to cover the entire length of the first direction, without requiring the second optical deflecting device 200 to deflect the beam at an angle in the first direction (vertical direction).

[0485] The optical deflection device in this embodiment is more suitable for scenarios where the field of view in the first direction (vertical direction) is less critical. In such scenarios, using a one-dimensional deflection LCPG module can simplify the structure of the LCPG module and reduce device costs.

[0486] Example 7

[0487] The optical deflection device provided in Embodiment 7 of the present invention is shown in the schematic diagram below. Figure 24 As shown. The optical deflection device provided in this embodiment differs from the optical deflection device in Embodiment 2 in that both the first optical deflection device 100 and the second optical deflection device 200 are one-dimensional deflectors, and they perform one-dimensional deflection in different directions, for example... Figure 24 As shown, the first optical deflecting device 100 deflects the light beam in the first direction, and the second optical deflecting device 200 deflects the light beam in the second direction. Alternatively, the first optical deflecting device 100 can deflect the light beam in the second direction, and the second optical deflecting device 200 can deflect the light beam in the first direction.

[0488] In this embodiment, the first optical deflection device deflects the light beam in one dimension, and the second optical deflection device deflects the light beam in one dimension, which is relatively suitable for situations where the light beam emitted by the light source is a long strip beam.

[0489] The second optical deflector 200 can adopt a partitioned structure or a non-partitioned structure. The case where the second optical deflector 200 adopts a partitioned structure is similar to that in Embodiment 2, and the case where the second optical deflector 200 adopts a non-partitioned structure is similar to that in Embodiment 4. The difference is that the second optical deflector 200 deflects the light beam in one dimension in one direction.

[0490] The optical deflection device in Embodiment 7 is more suitable for scenarios where the required field of view in the first direction (vertical direction) is relatively small. In such scenarios, using a one-dimensional deflection LCPG module simplifies the LCPG module's structure and reduces device costs. The second optical deflection device employs a partitioned structure, which also reduces the waiting time for angle switching. If the second optical deflection device uses a non-partitioned structure, to reduce the waiting time for deflection angle adjustment, the temperature of the second optical deflection device can be adjusted to accelerate the switching time of the liquid crystal molecule arrangement state. Alternatively, a blue phase liquid crystal with a correspondingly faster speed can be used to accelerate the angle switching time.

[0491] Example 8

[0492] The optical deflection device provided in Embodiment 8 of the present invention is shown in the schematic diagram below. Figure 25 As shown. The optical deflection device provided in Embodiment 7 differs from the optical deflection device in Embodiment 2 in that both the first optical deflection device 100 and the second optical deflection device 200 are one-dimensional deflectors, and both perform one-dimensional deflection in the same direction, for example... Figure 25 The beam deflection shown is performed in the first direction, but alternatively, the beam deflection can be performed in the second direction.

[0493] In this embodiment, the first optical deflection device deflects the light beam in one dimension, and the second optical deflection device deflects the light beam in one dimension, which is relatively suitable for situations where the light beam emitted by the light source is a long strip beam.

[0494] In the aforementioned optical deflection device, the angle range of the first optical deflection device deflecting the beam is equal to the angle interval between two adjacent second deflection angles of the second optical deflection device, so as to achieve high-precision deflection of the beam over a large angle range.

[0495] The optical deflection device in this embodiment is more suitable for scenarios where the field of view in the first direction (vertical direction) or the second direction (horizontal direction) is relatively small. In such scenarios, using a one-dimensional deflection LCPG module can simplify the structure of the LCPG module and reduce device costs. The second optical deflection device adopts a partitioned structure, which can also reduce the waiting time for angle switching.

[0496] The optical deflection device provided in this embodiment of the invention uses an AOD (Optical Optical Dispersion Device) as a one-dimensional fine scanning device. The AOD requires a high degree of collimation of the incident beam in the optical deflection direction, while the collimation requirement is relatively low in the direction perpendicular to the optical deflection direction. Therefore, the AOD can make the emitted beam appear as a stripe of light in the far field, narrow in the optical deflection direction and wide perpendicular to it. This is consistent with the light emission characteristics of current mainstream high-power semiconductor laser sources: the beam parametric product (BPP) of a high-power laser source composed of multiple light-emitting units (e.g., semiconductor EEL light sources) in the fast axis direction, i.e., the product of the beam waist radius and the divergence angle, is much smaller than the BPP in the slow axis direction. After being collimated by a lens and incident on the AOD, the beams in the optical deflection direction A and perpendicular to the optical deflection direction B can be collimated to approximately the same size, with the divergence angle A being much smaller than the divergence angle B, matching the characteristics of the AOD.

[0497] Building upon this, an LCPG is used as a coarse scanning device after the AOD (Aspect-Oriented Oscillator). The beam emitted from the AOD is deflected by a significant angle over time. For each angle to which the LCPG is deflected, the AOD performs a fine scan around that angle, achieving coverage of a wide field of view. During this process, the long side of the strip beam emitted from the AOD is perpendicular to the AOD's light deflection direction. This means that compared to a blocky scanning beam, the AOD can cover a larger field of view with the same total power. Therefore, the LCPG only needs to be deflected at fewer different angles to cover a larger overall field of view. This results in fewer LCPG layers required, lower cost, and faster response time.

[0498] This invention also provides a transmitting module, see [link to relevant documentation]. Figure 26 As shown, it includes a light source 300 and a light deflection device 10;

[0499] Light source 300 is used to emit a light beam to light deflection device 10;

[0500] The light deflection device 10 is used to deflect the incident light beam emitted by the light source 300 to generate scanning light with different deflection angles and deflection angle switching sequences to achieve scanning of the field of view.

[0501] The light source 300 includes at least one light source unit, which includes at least two light-emitting units 310 spliced ​​along the long axis to emit a strip-shaped incident beam with a required shape and size. The light source 300 includes any one or more combinations of a vertical-cavity surface-emitting laser, an edge-emitting laser, a light-emitting diode, a laser diode, a semiconductor laser, and a fiber laser.

[0502] The light beam emitted by the light source 300 can be either long or short.

[0503] In some embodiments, the strip beam emitted by the light source 300 has a length along a first direction that is shorter than its length along a second direction. The first direction is the deflection direction in which the first light deflecting device 100 deflects the incident beam, and the second direction is perpendicular to the first direction. In this case: the first light deflecting device 100 is configured to sequentially deflect the incident beam at multiple different first deflection angles in the first direction; the second light deflecting device 200 is configured to deflect the expanded beam at multiple different second deflection angles in a two-dimensional array in the first and second directions; or, the first light deflecting device 100 is configured to sequentially deflect the incident beam at multiple different first deflection angles in the first direction; and the second light deflecting device 200 is configured to deflect the expanded beam at multiple different second deflection angles in the second direction.

[0504] In some embodiments, the strip beam emitted by the light source 300 has a length along the second direction that is shorter than its length along the first direction. The second direction is the deflection direction of the incident beam by the first light deflecting device, and the second direction is perpendicular to the first direction. In this case, the first light deflecting device 100 is configured to deflect the incident beam sequentially by a plurality of different first deflection angles in the second direction; the second light deflecting device 200 is configured to deflect the expanded beam in the first and second directions by a plurality of different second deflection angles in a two-dimensional array manner; or, the first light deflecting device 100 is configured to deflect the incident beam sequentially by a plurality of different first deflection angles in the second direction; the second light deflecting device 200 is configured to deflect the expanded beam in the first direction by a plurality of different second deflection angles.

[0505] In some embodiments, the light source 300 emits a non-strip beam with an aspect ratio within a set threshold range; in this case:

[0506] The first optical deflector 100 is configured to sequentially deflect the incident beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflector 200 is configured to deflect the expanded beam in a first direction or a second direction by a plurality of different second deflection angles; or, the first optical deflector 100 is configured to sequentially deflect the incident beam in a two-dimensional array in a first direction and a second direction by a plurality of different first deflection angles; the second optical deflector 200 is configured to deflect the expanded beam in a two-dimensional array in a first direction and a second direction by a plurality of different second deflection angles; the second direction is perpendicular to the first direction.

[0507] This invention also provides a lidar system, the structure of which is described below. Figure 27 As shown, it includes a receiving module 2 and the aforementioned 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 sensed light signals.

[0508] This invention also provides an electronic device, including the aforementioned lidar system.

[0509] This invention also provides an optical scanning method, the process of which is described in [link to flowchart]. Figure 28 As shown, it includes:

[0510] S101: The first optical deflection device deflects the incident beam by multiple first deflection angles and projects the deflected beam onto the polarization amplification device;

[0511] In this step, the first optical deflector can be controlled by a controller to deflect the light beam. Within one deflection cycle, the first optical deflector deflects the light beam at multiple different first deflection angles in a preset order. The first optical deflector can be controlled to sequentially deflect the incident light beam at least one of a first direction and a second direction at multiple different first deflection angles; the first direction and the second direction are perpendicular.

[0512] The deflection period is the time required for the first optical deflector to deflect all of the multiple different first deflection angles, or the deflection period is the time required for the first optical deflector to deflect a specified portion of the first deflection angles.

[0513] Within one deflection cycle, the deflection angles of multiple beams with 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.

[0514] S102: The polarization amplification device amplifies the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, and projects the amplified beam onto the corresponding position of the second optical deflection device.

[0515] In this step, at least one polarizing lens amplifies the deflection angle of the light beam deflected by the first light deflecting device by a preset factor in at least one of the mutually perpendicular first and second directions. Optionally, at least one polarizing lens amplifies the deflection angle of the light beam deflected by the first light deflecting device by a preset factor in at least one of the mutually perpendicular first and second directions.

[0516] When the polarizing device includes two sets of cylindrical lenses, the first set of cylindrical lenses amplifies the deflection angle of the light beam deflected by the first light deflector in the first direction by a preset factor. The first set of cylindrical lenses includes a first polarizing cylindrical lens and a second polarizing cylindrical lens, and the preset factor is the ratio of the focal length of the first polarizing cylindrical lens to the focal length of the second polarizing cylindrical lens. The second set of cylindrical lenses amplifies the deflection angle of the light beam deflected by the first light deflector in the second direction by a preset factor. The second set of cylindrical lenses includes a third polarizing cylindrical lens and a fourth polarizing cylindrical lens, and the preset factor is the ratio of the focal length of the third polarizing cylindrical lens to the focal length of the fourth polarizing cylindrical lens; or

[0517] When the polarizing device includes two spherical lenses, the first polarizing spherical lens and the second polarizing spherical lens amplify the deflection angle of the light beam deflected by the first light deflecting device in the first direction and the second direction by a preset factor. The preset factor is the ratio of the focal length of the first polarizing spherical lens to the focal length of the second polarizing spherical lens.

[0518] S103: The second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam.

[0519] In this step, a second optical deflector can be controlled by a controller to deflect the beam. The second optical deflector deflects the amplified beam in at least one of the first and second directions by multiple different second deflection angles. Optionally, the multiple second deflection angles deflecting the incident beam within one deflection cycle may be the same, different, or partially the same and partially different.

[0520] In some embodiments, the method further includes: amplifying the divergence angle of the beam deflected by the first optical deflection device in the corresponding deflection direction by a preset factor to form a strip beam; and the amplification factor of the divergence angle is the same as the amplification factor of the deflection angle of the beam in the deflection direction.

[0521] In some embodiments, among a plurality of different first deflection angles for deflecting the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the beam after deflection by the first optical deflection device along the deflection direction.

[0522] In some embodiments, the deflection accuracy of the beam deflection at the first deflection angle is higher than the deflection accuracy of the beam deflection at the second deflection angle.

[0523] In some embodiments, the method further includes: before the incident beam is incident on the first optical deflector, a collimating device collimates the incident beam in a first direction and a second direction respectively; the first direction is the direction in which the first optical deflector deflects the incident beam, and the collimation requirement in the first direction is higher than the collimation requirement in the second direction. The first direction is perpendicular to the second direction.

[0524] In some embodiments, the collimating device collimates the incident beam in a first direction and a second direction, respectively, including:

[0525] One cylindrical lens collimates the incident beam along a first direction, and another cylindrical lens collimates the incident beam along a second direction; or

[0526] A spherical lens simultaneously collimates the incident beam along a first direction and a second direction; or

[0527] A cylindrical lens collimates the light beam along a first direction, and a spherical lens collimates the light beam simultaneously along both the first and second directions.

[0528] In some embodiments, the divergence angle of the collimated beam after collimation in the first direction is less than 1 / 10 of the divergence angle after collimation in the second direction.

[0529] In some embodiments, the following relationships are satisfied between the incident beam's emission width V1 in the first direction, its divergence angle θ1 in the first direction when emitted from the emission position, its beam waist diameter V2 in the first direction when the beam is incident on the first optical deflector, its divergence angle θ2 in the first direction when the beam is incident on the first optical deflector, and the focal length F2 of the collimating lens that collimates the beam along the first direction: θ2=V1 / F2,θ2V2=θ1V1.

[0530] The following relationships are satisfied between the incident beam's emission length H1 in the second direction when it is emitted from the emission position, the beam waist diameter H2 in the second direction when it is incident on the first optical deflector, the beam divergence angle Θ2 in the second direction when it is incident on the first optical deflector, and the focal length F1 of the collimating lens that collimates the beam along the second direction: Θ2=H1 / F1,Θ2H2=Θ1H1.

[0531] In some embodiments, the incident beam is a strip beam emitted from the emission position with an aspect ratio of 20:1 to 100:1; the beam incident on the first optical deflector has an aspect ratio of 3:1 to 1:2; and the scanning beam is a strip beam with an aspect ratio of 20:1 to 80:1.

[0532] Optionally, the aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; and the aspect ratio of the scanning beam is 75:1. Alternatively, the aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; and the aspect ratio of the scanning beam is 25:1.

[0533] In some embodiments, when the second optical deflection device employs a partitioned structure...

[0534] In step S102 above, the first optical deflection device deflects the incident beam at multiple different first deflection angles in a preset order within one deflection period.

[0535] In step S102 above, projecting the polarized beam onto the corresponding position of the second optical deflection device includes: the polarized beam is incident on the corresponding deflection zone of the second optical deflection device.

[0536] In step S103 above, the second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam. This includes: the controller controlling multiple deflection partitions in the second optical deflection device to receive amplified beams corresponding to multiple incident beams with different first deflection angles; each deflection partition can individually adjust the deflection angle of the incident beam; controlling the currently scanned deflection partition to deflect the incident beam by the required second deflection angle; and controlling at least one currently unscanned deflection partition to adjust the deflection angle of the incident beam to the required second deflection angle for the next deflection cycle after the current deflection cycle has been scanned by the incident beam and before the next deflection cycle begins to be scanned by the incident beam.

[0537] The control of multiple deflection zones in the second optical deflection device to receive multiple incident beams with different first deflection angles includes: controlling multiple deflection zones to receive multiple beams with different first deflection angles at different times.

[0538] When the first optical deflector deflects multiple beams with different first deflection angles at 100 minutes, multiple deflection partitions are controlled to receive multiple beams with different first deflection angles at 212 minutes. The aforementioned control of at least one currently unscanned deflection partition to adjust its beam deflection angle to the second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the beam, before the next deflection cycle begins scanning, includes: determining that after a deflection partition has completed beam deflection in the current deflection cycle and is in a non-scanning state, controlling that deflection partition to adjust its beam deflection angle to the second deflection angle required for the next deflection cycle before entering the scanning state in the next deflection cycle.

[0539] Optionally, if a deflection partition is the deflection partition currently being scanned by the beam, then 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 being scanned by the beam or the next deflection partition to be scanned, then the deflection partition is determined to be in a scanning state; otherwise, the deflection partition is determined to be in a non-scanning state.

[0540] Further optionally, when the deflection partition currently being scanned by the beam and the next deflection partition to be scanned are determined as deflection partitions in the scanning state, and the remaining deflection partitions are determined as deflection partitions in the non-scanning state, the deflection partition currently being scanned by the beam and the next deflection partition to be scanned are deflection partitions that are adjacent in position.

[0541] In some embodiments, the multiple second deflection angles deflecting the beam within one deflection cycle are all the same, all different, or partially the same and partially different. A deflection partition may sequentially receive one, two, or more incident beams with different first deflection angles within one deflection cycle. Multiple deflection partitions are configured such that the multiple second deflection angles deflecting the beam within one deflection cycle are all the same, all different, or partially the same and partially different.

[0542] In some embodiments, the number of beams that each deflection partition can receive is the same, different, or partially the same and partially different; correspondingly, the widths of the multiple deflection partitions are the same, different, or partially the same and partially different.

[0543] In some embodiments, the voltage applied to the electrodes of each deflection zone is controlled to adjust the refractive index of the medium in the deflection zone to the light beam, thereby adjusting the deflection angle of the deflection zone to the light beam. When the second optical deflection device employs a liquid crystal polarization grating, the voltage applied to the electrodes of each deflection zone 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 deflection zone to the light beam.

[0544] Optionally, the second optical deflection device includes at least one optical deflection unit, which includes multiple deflector partitions. If the deflection partitions include the deflector partitions corresponding to the positions in the at least one optical deflection unit, the voltage on the two end electrodes of each deflector partition is controlled respectively. By changing the voltage on the two end electrodes of at least one deflector partition, the deflection angle of at least one deflector partition to the light beam is changed, thereby changing the second deflection angle of the corresponding deflector partition to the light beam.

[0545] Optionally, if the second optical deflection device includes at least two optical deflection unit groups, each optical deflection unit group including at least one of the optical deflection units; the second deflection angle required to control the currently scanned deflection partition to deflect the beam includes: the second deflection angle required to deflect the beam in the first direction by the deflection partition currently scanned by the optical deflection unit in at least one optical deflection unit group, and / or the second deflection angle required to deflect the beam in the second direction by the deflection partition currently scanned by the optical deflection unit in at least one optical deflection unit group, wherein the first direction and the second direction are perpendicular.

[0546] In some embodiments, the adjustment time for the second deflection angle of the beam by the deflection partition adjustment is no greater than the time interval between two adjacent scans of the deflection partition by the beam.

[0547] In some embodiments, the number of deflection partitions is determined based on the number of second deflection angles deflected by the second optical deflector, the time required for the second optical deflector to deflect multiple beams with multiple different first deflection angles to multiple different second deflection angles, and the adjustment time required for the second optical deflector to complete one deflection angle adjustment. Optionally, the number of deflection partitions D is an integer greater than or equal to 2 / (1-FMT), where M is the number of deflection angles of the second optical deflector, 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 deflector to complete one deflection angle adjustment.

[0548] In some embodiments, the following control processes are executed in parallel: controlling the currently scanned deflection partition in the second optical deflection device to deflect the beam, and controlling at least one currently unscanned deflection partition to adjust its deflection angle to the beam.

[0549] In some embodiments, the field of view of the light scan is divided into multiple scanning partitions, each of which is rectangular, and the length of the field of view in a first direction is less than its length in a second direction. The incident beam is a strip beam; scanning the field of view includes: deflecting multiple beams with different first deflection angles to the same second deflection angle to complete the scanning of one corresponding scanning partition of the field of view; deflecting each beam with a different first deflection angle to multiple different second deflection angles to complete the scanning of multiple scanning partitions corresponding to the different second deflection angles; the length of the beam after deflection by the second deflection angle is equal to the length of one direction of the scanning partition.

[0550] Optionally, within one deflection cycle, multiple beams with different first deflection angles are deflected to the same second deflection angle to complete the scanning of a corresponding scanning partition of the field of view; each deflection cycle corresponds to different second deflection angles; different deflection cycles result in different second deflection angles for the multiple beams with different first deflection angles.

[0551] Optionally, within one deflection cycle, multiple beams with different first deflection angles are deflected to one of multiple different second deflection angles respectively, and scan a portion of the corresponding scanning partition; wherein, within one deflection cycle, the second deflection angles of the multiple beams with different first deflection angles are the same or different; the second deflection angles of the beams with each first deflection angle are different in different deflection cycles.

[0552] In some embodiments, the method further includes: changing the temperature of the second optical deflector to change the time for the second optical deflector to adjust the deflection angle.

[0553] The methods described in the embodiments of the present invention have been described in detail in the relevant parts of the transmitting module and the lidar system, and will not be repeated here.

[0554] In the above description of the embodiments of the present invention, when multiple are mentioned, it should be understood that two or more are included.

[0555] Unless otherwise specifically stated, terms such as processing, calculation, operation, determination, display, etc., may refer to the actions and / or processes of one or more processing or computing systems or similar devices that represent the manipulation and conversion of data representing physical (e.g., electronic) quantities within the registers or memory of the processing system into other data similarly representing physical quantities within the memory, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals can be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description can be represented by voltage, current, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0556] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0557] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0558] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0559] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0560] 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. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

[0561] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as interpreted when used as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. An optical scanning method, characterized in that, include: The first optical deflection device deflects the incident beam by multiple first deflection angles and projects the deflected beam onto the polarization amplification device; The polarization amplification device amplifies the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, and projects the amplified beam onto the corresponding position of the second optical deflection device. The second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam.

2. The method as described in claim 1, characterized in that, The first optical deflector deflects the incident beam by multiple first deflection angles, including: The first optical deflection device deflects the incident light beam sequentially in at least one of the first and second directions by multiple different first deflection angles. The second optical deflection device deflects the amplified beam by a preset second deflection angle, including: The second optical deflection device deflects the amplified beam at least in one of the first and second directions by multiple different second deflection angles; the first and second directions are perpendicular.

3. The method as described in claim 1, characterized in that, The polarization amplification device amplifies the deflection angle of the deflected beam in the corresponding deflection direction by a preset factor, including: At least one polarizing lens amplifies the deflection angle of the light beam deflected by the first light deflection device by a predetermined factor in at least one of the mutually perpendicular first and second directions.

4. The method as described in claim 3, characterized in that, At least one polarizing lens amplifies the deflection angle of the light beam deflected by the first optical deflecting device by a predetermined factor in at least one of a first direction and a second direction that are perpendicular to each other, including: The first cylindrical lens group amplifies the deflection angle of the light beam deflected by the first light deflection device in the first direction by a preset factor. The first cylindrical lens group includes a first polarizing cylindrical lens and a second polarizing cylindrical lens. The preset factor is the ratio of the focal length of the first polarizing cylindrical lens to the focal length of the second polarizing cylindrical lens. The second cylindrical lens group amplifies the deflection angle of the light beam deflected by the first light deflection device in the second direction by a preset factor. The second cylindrical lens group includes a third polarizing cylindrical lens and a fourth polarizing cylindrical lens. The preset factor is the ratio of the focal length of the third polarizing cylindrical lens to the focal length of the fourth polarizing cylindrical lens. or The first and second polarizing spherical lenses amplify the deflection angle of the light beam deflected by the first light deflecting device in the first and second directions by a preset factor, which is the ratio of the focal length of the first polarizing spherical lens to the focal length of the second polarizing spherical lens.

5. The method as described in claim 1, characterized in that, Also includes: The divergence angle of the beam deflected by the first optical deflection device is amplified by a preset factor in the corresponding deflection direction, and the amplification factor of the divergence angle is the same as the amplification factor of the deflection angle of the beam in that deflection direction.

6. The method as described in claim 1, characterized in that, Within one deflection period, the deflection angle of the multiple beams with different first deflection angles varies from large to small, or from small to large, or varies according to a preset random rule in each deflection direction. Multiple second deflection angles that deflect the beam within a deflection cycle may be the same, different, or partially the same and partially different.

7. The method as described in claim 1, characterized in that, The step of projecting the polarized beam onto the corresponding position of the second optical deflection device includes: the polarized beam being incident on the corresponding deflection zone of the second optical deflection device. The second optical deflection device deflects the amplified beam by a preset second deflection angle to project a scanning beam, including: The controller controls multiple deflection zones in the second optical deflection device to receive amplified beams corresponding to beams with multiple different first deflection angles; the deflection angle of each deflection zone can be adjusted individually. The second deflection angle required to deflect the beam by controlling the currently scanned deflection zone; and Control at least one currently unscanned deflection zone to adjust the beam deflection angle to the second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the beam and before the next deflection cycle begins to be scanned by the beam.

8. The method as described in claim 7, characterized in that, The control of the first optical deflection device to deflect the incident beam by multiple first deflection angles includes: controlling the first optical deflection device to deflect the incident beam by multiple different first deflection angles in a preset order within one deflection period. Controlling multiple deflection zones in a second optical deflection device to receive multiple beams with multiple different first deflection angles includes: controlling the multiple deflection zones to receive multiple beams with multiple different first deflection angles at different times; The deflection period is the time required for the first optical deflector to deflect all of the multiple different first deflection angles, or the deflection period is the time required for the first optical deflector to deflect a specified portion of the first deflection angles.

9. The method as described in claim 7, characterized in that, A deflection zone can sequentially receive one, two, or more incident beams with different first deflection angles within one deflection cycle; The plurality of deflection zones are configured such that the plurality of second deflection angles deflecting the incident beam within one deflection cycle are all the same, all different, or partially the same and partially different. The number of incident beams that each deflection partition can receive is the same, all different, or partially the same and partially different; correspondingly, the widths of the plurality of deflection partitions are all the same, all different, or partially the same and partially different.

10. The method as described in claim 7, characterized in that, The control of at least one currently unscanned deflection zone to adjust the deflection angle of the incident beam to the second deflection angle required for the next deflection cycle after the current deflection cycle has been scanned by the beam and before the next deflection cycle begins to be scanned by the incident beam includes: Once a deflection zone has completed the deflection of the incident beam in the current deflection cycle and is in a non-scanning state, the deflection zone is controlled to adjust its deflection angle to the beam. Before entering the scanning state in the next deflection cycle, its deflection angle to the beam is adjusted to the second deflection angle required for the next deflection cycle.

11. The method as described in claim 10, characterized in that, If a deflection zone is the deflection zone currently being scanned by the incident beam, then the deflection zone is determined to be in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state. If a deflection zone is the deflection zone that the incident beam is currently scanning or the next deflection zone to be scanned, then it is determined to be in a scanning state; otherwise, the deflection zone is determined to be in a non-scanning state.

12. The method as described in claim 10, characterized in that, The deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are defined as deflection partitions in the scanning state, and the remaining deflection partitions are defined as deflection partitions in the non-scanning state; the deflection partition currently being scanned by the incident beam and the next deflection partition to be scanned are deflection partitions that are adjacent in position.

13. The method as described in claim 7, characterized in that, By controlling the voltage applied to the electrodes of each deflection zone, the refractive index of the medium in the deflection zone to the incident beam is adjusted, thereby adjusting the deflection angle of the deflection zone to the incident beam. The adjustment time for the second deflection angle of the incident beam by the deflection partition adjustment is no greater than the time interval between two adjacent scans of the deflection partition by the incident beam.

14. The method as described in claim 7, characterized in that, When the second optical deflection device uses a liquid crystal polarization grating, the voltage applied to the electrodes of each deflection zone 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 deflection zone to the incident beam.

15. The method as described in claim 7, characterized in that, The second optical deflection device includes at least one optical deflection unit, which includes multiple deflection rotor sections. When the deflection section includes the deflection rotor section corresponding to the position in the at least one optical deflection unit, the voltage on the two end electrodes of each deflection rotor section is controlled respectively. By changing the voltage on the two end electrodes of at least one deflection rotor section, the deflection angle of at least one deflection rotor section to the incident light beam is changed, so as to change the second deflection angle of the corresponding deflection section to the incident light beam.

16. The method as described in claim 7, characterized in that, The second optical deflection device includes at least two optical deflection unit groups, wherein each optical deflection unit group includes at least one of the optical deflection units; The second deflection angle required to deflect the incident beam by the currently depicted deflection zone includes: The incident beam is deflected in the first direction by a second deflection angle required by the deflector partition of the optical deflection unit currently being scanned in at least one optical deflection unit group, and / or the incident beam is deflected in the second direction by a second deflection angle required by the deflector partition of the optical deflection unit currently being scanned in at least one optical deflection unit group, wherein the first direction and the second direction are perpendicular.

17. The method as described in claim 7, characterized in that, 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 multiple 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.

18. The method as described in claim 7, characterized in that, The number of deflection partitions D 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 deflection of M deflection angles, and T is the time required for the second optical deflection device to complete one deflection angle adjustment.

19. The method as described in claim 7, characterized in that, The following control processes are executed in parallel: controlling the currently scanned deflection partition in the second optical deflection device to deflect the beam, and controlling at least one currently unscanned deflection partition to adjust its deflection angle to the beam.

20. The method as described in claim 7, characterized in that, The field of view of the optical scan is divided into multiple scanning zones, each of which is rectangular, and the incident beam is a strip beam. Scanning the field of view includes: deflecting multiple incident beams with different first deflection angles to the same second deflection angle to complete the scanning of one corresponding scanning partition of the field of view; and deflecting each beam with a first deflection angle of multiple incident beams with different first deflection angles to multiple different second deflection angles to complete the scanning of multiple scanning partitions corresponding to the multiple second deflection angles. The length of the beam after the second deflection angle is equal to the length of one direction of the scanning partition.

21. The method as described in claim 20, characterized in that, Within one deflection cycle, multiple incident beams with different first deflection angles are deflected to the same second deflection angle to complete the scanning of a corresponding scanning zone of the field of view; each deflection cycle corresponds to different second deflection angles; different deflection cycles result in different second deflection angles for the multiple incident beams with different first deflection angles. or Within one deflection cycle, incident beams with multiple different first deflection angles are deflected to one of multiple different second deflection angles, and scan a portion of the corresponding scanning partition. Within one deflection cycle, the second deflection angles of the incident beams with multiple different first deflection angles may be the same or different. The second deflection angles of the incident beams with each first deflection angle are different in different deflection cycles.

22. The method as described in claim 7, characterized in that, Also includes: Changing the temperature of the second optical deflector changes the time it takes for the second optical deflector to adjust its deflection angle.

23. The optical deflection device as described in claim 1, characterized in that, The first optical deflection device has a higher deflection accuracy for the light beam than the second optical deflection device. Among multiple different first deflection angles that deflect the incident beam, the angular interval between two adjacent first deflection angles is less than or equal to the divergence angle of the beam along the deflection direction after being deflected by the first optical deflection device.

24. The method according to any one of claims 1-23, characterized in that, Also includes: Before the incident beam is incident on the first optical deflection device, the collimation device collimates the incident beam in the first direction and the second direction respectively. The first direction is the direction in which the first optical deflection device deflects the incident beam, and the collimation requirement in the first direction is higher than the collimation requirement in the second direction.

25. The method as described in claim 24, characterized in that, The divergence angle of the collimated beam after collimation in the first direction is less than 1 / 10 of the divergence angle after collimation in the second direction.

26. The method as described in claim 24, characterized in that, The collimating device collimates the incident beam in a first direction and a second direction, respectively, including: One cylindrical lens collimates the incident beam along a first direction, and another cylindrical lens collimates the incident beam along a second direction; or A spherical lens simultaneously collimates the incident beam along a first direction and a second direction; or A cylindrical lens collimates the light beam along a first direction, and a spherical lens collimates the light beam simultaneously along both the first and second directions.

27. The method as described in claim 24, characterized in that, The following relationships are satisfied between the incident beam's emission width V1 in the first direction, its divergence angle θ1 in the first direction when emitted from the emission position, its beam waist diameter V2 in the first direction when the beam is incident on the first optical deflector, its divergence angle θ2 in the first direction when the beam is incident on the first optical deflector, and the focal length F2 of the collimating lens that collimates the beam along the first direction: θ2=V1 / F2,θ2V2=θ1V1; The following relationships are satisfied between the incident beam's emission length H1 in the second direction when it is emitted from the emission position, the beam waist diameter H2 in the second direction when it is incident on the first optical deflector, the beam divergence angle Θ2 in the second direction when it is incident on the first optical deflector, and the focal length F1 of the collimating lens that collimates the beam along the second direction: Θ2=H1 / F1,Θ2H2=Θ1H1.

28. The method as described in claim 24, characterized in that, The incident beam is a strip beam emitted from the emission position with an aspect ratio of 20:1 to 100:1; the beam incident on the first optical deflector has an aspect ratio of 3:1 to 1:2; the scanning beam is a strip beam with an aspect ratio of 20:1 to 80:

1.

29. The method as described in claim 24, characterized in that, The aspect ratio of the incident beam emitted from its position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; the aspect ratio of the scanning beam is 75:1; or The aspect ratio of the incident beam emitted from the emission position is 50:1; the aspect ratio of the beam incident on the first optical deflector is 5:2; and the aspect ratio of the scanning beam is 25:1.

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