WO2023083109A1 - 用于激光雷达的发射器和激光雷达 - Google Patents

用于激光雷达的发射器和激光雷达 Download PDF

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Publication number
WO2023083109A1
WO2023083109A1 PCT/CN2022/129832 CN2022129832W WO2023083109A1 WO 2023083109 A1 WO2023083109 A1 WO 2023083109A1 CN 2022129832 W CN2022129832 W CN 2022129832W WO 2023083109 A1 WO2023083109 A1 WO 2023083109A1
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divergence angle
laser
transmitter
present disclosure
initial
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PCT/CN2022/129832
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English (en)
French (fr)
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郝成龙
谭凤泽
朱健
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深圳迈塔兰斯科技有限公司
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Publication of WO2023083109A1 publication Critical patent/WO2023083109A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/481—Constructional features, e.g. arrangements of optical elements
    • G01S7/4814—Constructional features, e.g. arrangements of optical elements of transmitters alone
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
    • G01S17/88—Lidar systems specially adapted for specific applications
    • G01S17/89—Lidar systems specially adapted for specific applications for mapping or imaging
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/483—Details of pulse systems
    • G01S7/484—Transmitters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
    • G01S7/491—Details of non-pulse systems
    • G01S7/4911—Transmitters

Definitions

  • the present disclosure relates to the technical field of optical metalens, and in particular, the present disclosure relates to a transmitter for lidar and lidar.
  • Lidar is a scanning sensor that uses non-contact laser ranging technology. Its working principle is similar to that of a general radar system, that is, it detects targets by emitting laser beams, and forms point clouds and acquires data by collecting reflected beams. , these data can be generated into accurate three-dimensional images after photoelectric processing. With this technology, high-precision physical space environment information can be accurately obtained, and the ranging accuracy can reach centimeter level. Therefore, lidar is widely used as a basic component in scientific and industrial fields such as automotive autonomous driving, precision modeling, and 3D remote sensing.
  • LiDAR is mainly composed of transmitter, receiver, signal processing unit and display unit.
  • the transmitter mainly includes a laser source, an optical modulation module, a beam control module and a scanning control module. Specifically, after optical modulation and beam control by the optical modulation module and beam control module, the laser light emitted by the laser source is projected into the space under the control of the scanning control module, so that the laser beam scans in the space in a specific way.
  • the laser beam irradiates the target, the phenomenon of scattering occurs, and the scattered photoelectric signal is received by the receiver of the laser radar, and then converted into an electrical signal by the signal processing unit, amplified and information processed, so as to display the target signal on the display unit .
  • the scanning control module of the traditional laser radar transmitter is mainly realized by using a mechanical scanning module and a MEMS micro-vibration mirror scanning module.
  • the non-mechanical scanning laser radar transmitter does not have rotating components, the hardware cost and wear consumption are reduced to a certain extent, and it can continue to work even when individual devices in the light source array are damaged, making the reliability A great improvement has been achieved on the surface, so it has received extensive attention.
  • a metalens is a flat lens manufactured by a semiconductor process, which has the advantages of small size (thin thickness), light weight, simple structure, low cost, and high productivity. Due to the aforementioned advantages, metalenses can also be used in emitters for LiDAR. However, in the prior art, metalenses are only used to collimate laser light in the transmitter of LiDAR, while the generation of multi-lines still requires multiple laser light sources arranged in predetermined orientations, and the generation of far-field point clouds is still Diffractive optical elements are required, which do not take advantage of the metalenses described above.
  • An object of the present disclosure is to provide a metalens-based transmitter for lidar and a lidar using the same.
  • a transmitter for lidar which includes: a laser surface light source emitting an initial beam with an initial divergence angle; a first hyperlens, the initial beam passes through the first hyperlens, so that it has An initial light beam with an initial divergence angle is transformed into a first light beam with a first divergence angle; a second metalens, the first light beam passes through the second metalens such that the first light beam with the first divergence angle is transformed into a second light beam with a second divergence angle of the second beam, the second beam is used to generate point clouds or multilines in the far field, where the first metalens is located between the second metalens and the laser surface light source, and where the first divergence angle is smaller than the initial divergence angle, And the second divergence angle is smaller than the first divergence angle.
  • a ratio between the first divergence angle and the initial divergence angle is less than 1/5.
  • the second divergence angle is determined by the furthest working distance of the lidar and the smallest size of an object detectable at the furthest working distance.
  • the laser surface light source includes a plurality of laser source arrays, and each laser source array is composed of a plurality of laser sources.
  • multiple laser source arrays are sequentially turned on in a predetermined sequence.
  • multiple laser source arrays are randomly lit.
  • the laser source array corresponding to the central field of view is turned on more than the laser source arrays outside the central field of view.
  • each of the first hyperlens and the second hyperlens includes a substrate and a microstructure layer disposed on the substrate, and wherein the microstructure layer includes microstructure units arranged in an array.
  • the size and shape of the microstructure unit are determined according to the working band of the laser radar.
  • point clouds or multilines are generated at the far field by adjusting the phase of the initial beam.
  • a lidar comprising the transmitter according to the above aspect of the present disclosure.
  • a metalens can be used to simultaneously realize the function of generating far-field point clouds or multi-lines and the function of beam collimation, thereby reducing the number of lenses in the transmitter, thereby reducing the overall cost of the laser radar. size, weight and cost.
  • a laser surface light source composed of a laser source array can be used to implement a non-mechanical scanning emitter, thereby reducing the complexity of the emitter and improving the overall service life of the lidar.
  • FIG. 1 shows a schematic diagram of a configuration of a transmitter for lidar according to an embodiment of the present disclosure.
  • FIG. 2 shows a plan view of a laser surface light source according to an embodiment of the present disclosure.
  • 3A to 3D show schematic diagrams of examples in which laser source arrays included in a laser surface light source are sequentially turned on according to an embodiment of the present disclosure.
  • FIGS. 4A and 4B illustrate perspective views of one microstructure unit of the first and second hyperlenses according to an embodiment of the present disclosure.
  • 5A and 5B illustrate plan views of microstructure layers of first and second metalens according to embodiments of the disclosure.
  • 6A-6C show schematic diagrams of configurations of transmitters for lidar according to alternative embodiments of the present disclosure.
  • FIG. 7 shows a schematic diagram of a configuration of a transmitter 700 for lidar according to an example of the present disclosure.
  • Figure 8A shows the relationship between focal plane spot size and field of view angle when point cloud phase is not considered.
  • Figure 8B shows a graph of the modulation transfer function corresponding to Figure 8A.
  • FIG. 9A shows a phase diagram of a first metalens according to an example of the present disclosure
  • FIG. 9B shows a phase diagram of a second metalens according to an example of the present disclosure
  • FIG. 9C shows a phase diagram of a second metalens according to an example of the present disclosure.
  • FIG. 10 is a graph showing the relationship between the transmittance and phase of the square nanopillars at the working wavelength band of 905 nm and the side length of the square nanopillars according to an example of the present disclosure.
  • Embodiments are described herein with reference to cross section illustrations that are idealized embodiments. Accordingly, variations in shape from the illustrations as a result, for example, of manufacturing techniques and/or tolerances are to be expected. Thus, embodiments described herein should not be construed as limited to the particular shapes of regions as illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. For example, a region illustrated or described as flat may, typically, have rough and/or nonlinear features. Also, acute corners shown may be rounded. Thus, the regions shown in the figures are schematic in nature and their shapes are not intended to illustrate the precise shape of a region and are not intended to limit the scope of the claims.
  • FIG. 1 shows a schematic diagram of a configuration of a transmitter 100 for lidar according to an embodiment of the present disclosure.
  • the transmitter 100 for lidar includes: a laser surface light source 101, which emits an initial beam L 0 with an initial divergence angle ⁇ 0 ; a first hyperlens 102, through which the initial beam L 0 passes The first hyperlens 102, so that the initial beam L 0 with the initial divergence angle ⁇ 0 is transformed into the first beam L 1 with the first divergence angle ⁇ 1 ; the second hyperlens 103, the first beam L 1 passes through the second hyperlens lens 103 such that the first light beam L 1 with a first divergence angle ⁇ 1 is transformed into a second light beam L 2 with a second divergence angle ⁇ 2 for generating a point cloud or multiple line, where the first metalens 102 is located between the second metalens 103 and the laser surface light source 101, and where the first divergence angle L 1 is smaller than the initial divergence angle L 0 , and the second divergence angle ⁇ 2 is
  • the second divergence angle ⁇ 2 is extremely small, close to zero, that is, the second light beam L 2 is approximately parallel light, so the specific position of the second divergence angle ⁇ 2 is not clearly marked in Fig. 1 .
  • FIG. 2 shows a plan view of a laser surface light source 101 according to an embodiment of the present disclosure.
  • the laser surface light source 101 includes a plurality of laser source arrays, and each laser source array is composed of a plurality of laser sources.
  • the laser surface light source 101 may be in the form of a laser source array.
  • the laser surface light source 101 may include N laser source arrays 101-i with the same structure, where 1 ⁇ i ⁇ N.
  • N is a square number of a natural number greater than 1, such as 4, 9, 16, 25 and so on.
  • each laser source array is composed of a plurality of laser sources.
  • each laser source array may include M laser sources with the same structure, where M is a natural number greater than 1.
  • each laser source array 101-i may also include a greater or lesser number of laser sources.
  • the laser sources in each laser source array 101-i are shown as being arranged in a square form in FIG. Arranged in the form of polygons, or in the form of other shapes with spatial symmetry.
  • the laser light emitted by the laser surface light source 101 is compressed and collimated by the first hyperlens 102 and the second hyperlens 103 to generate a point cloud or multiple lines in the far field. Since the laser sources at different positions on the laser surface light source 101 correspond to different exit angles at the second hyperlens 103, and then correspond to different field angles at the far field, the non-central field of view of the laser surface light source 101 The laser beam emitted by the laser source at corresponds to the obliquely outgoing far-field parallel light and the corresponding point cloud or multiline.
  • the laser light emitted by the laser source at the center position 1 of the field of view of the laser surface light source 101 passes through the second hyperlens 103 with respect to the field of view angle of the direction perpendicular to the laser surface light source 101 to be 0. .
  • the laser light emitted by the laser source at position 2 off the center of the field of view of the surface laser light source 101 has an angle of view of 15° relative to the direction perpendicular to the surface laser light source 101 after passing through the second hyperlens 103 .
  • the laser light emitted by the laser source at position 3 away from the center of the field of view of the laser surface light source 101 has an angle of view of 30° relative to the direction perpendicular to the laser surface light source 101 after passing through the second hyperlens 103 .
  • the plurality of laser source arrays 101-i included in the laser surface light source 101 are turned on sequentially.
  • the laser source of the non-central field of view of the laser surface light source 101 corresponds to the obliquely emitted far-field parallel light and the corresponding point cloud or multiline, it is possible to use the laser source array included in the laser surface light source 101 to light up sequentially. way to scan in the far field.
  • 3A to 3D are schematic diagrams illustrating an example of lighting up of the laser source array 101 - i included in the laser surface light source 101 according to an embodiment of the present disclosure.
  • multiple laser source arrays 101-i are sequentially turned on in a predetermined sequence. As shown by the arrows in FIG. 3A , the laser source array 101 - i can be turned on sequentially in an S-shaped manner in the horizontal direction. According to an embodiment of the present disclosure, as shown by the arrows in FIG. 3B , the laser source arrays 101 - i may be turned on sequentially in an S-shaped manner in the vertical direction. According to an embodiment of the present disclosure, as shown by the arrow in FIG. 3C , the laser source array 101 - i can be turned on sequentially in an outward spiral manner starting from the laser source array at the center of the field of view. After each of the laser source arrays 101-i is turned on once, one scan cycle is completed, and then the next scan cycle starts.
  • the lighting mode of the laser source array 101-i included in the laser surface light source 101 that is, the scanning mode is not limited to the examples shown in FIGS. 3A to 3C .
  • the source arrays 101-i can also be turned on sequentially in other set order.
  • the plurality of laser source arrays 101-i can also be randomly lit. Specifically, in one scanning period, the multiple laser source arrays 101-i can be turned on in random order, as long as each of the multiple laser source arrays 101-i is turned on once. After each of the laser source arrays 101-i is turned on once, one scan cycle is completed, and then the next scan cycle starts.
  • the laser source arrays corresponding to the central field of view are turned on more often than those corresponding to the laser source arrays outside the central field of view.
  • the laser source array corresponding to the central field of view area is marked by a dashed box.
  • the central field of view needs to be scanned multiple times in each scan cycle.
  • the number of times of lighting the laser source array outside the central field of view can be set to 1 in each scanning period, and the number of times of turning on the laser source array inside the central field of view (inside the dotted line frame) can be set to 1.
  • the number of lighting times of the laser source array is set to m, where m is a natural number greater than or equal to 2.
  • the laser source array 101-i in each scanning period, can be turned on in a preset order, wherein the laser source array outside the central field of view is only turned on once, while the central field of view The laser source array inside is lit m times. This scanning method of different lighting times (frequency) of laser source arrays at different positions can ensure that the lidar has a sufficient refresh frequency for the front central field of view.
  • the plurality of laser source arrays 101-i included in the laser surface light source 101 can also be randomly lit, as long as the number of laser light source arrays corresponding to the central field of view is greater than those corresponding to the outside of the central field of view The number of times the laser source array is lit is enough, which can reduce the crosstalk problem of point cloud data in a similar field of view that may be caused during the process of sequentially lighting up the laser source array.
  • a metalens is a specific application of a metasurface.
  • a metasurface is a layer of subwavelength artificial nanostructure film that can modulate incident light according to the metasurface microstructure units on it.
  • the microstructure units of the metasurface contain all-dielectric or plasmonic nanoantennas, which can directly adjust the phase, amplitude and polarization of light.
  • 4A and 4B illustrate perspective views of one microstructure unit of the first hyperlens 102 and the second hyperlens 103 according to an embodiment of the present disclosure.
  • 5A and 5B illustrate plan views of the microstructure layers of the first and second hyperlenses 102, 103, according to embodiments of the disclosure.
  • each of the first hyperlens 102 and the second hyperlens 103 includes a substrate and a microstructure layer disposed on the substrate, wherein the microstructure layer includes array of microstructural units.
  • microstructure units may be arranged in a regular hexagonal array.
  • microstructure units may be arranged in a square array.
  • the microstructure units included in the microstructure layer may also include other forms of array arrangement, and all these variants are within the scope of the present disclosure.
  • the microstructure unit may have a nanostructure.
  • nanostructures are provided at the center and/or apex of each microstructure unit.
  • nanostructures are all-dielectric building blocks.
  • the nanostructure has high transmittance in the near-infrared light band.
  • nanostructures may be formed from at least one of the following materials: titanium oxide, silicon nitride, fused silica, aluminum oxide, gallium nitride, gallium phosphide, amorphous silicon, crystalline silicon, and hydrogenated amorphous silicon etc.
  • the nanostructures in the microstructural units of the metalens may have the form of nanopillars.
  • the cross section of the nanopillar shown in FIG. 4A is circular and the cross section of the nanopillar shown in FIG. 4B is square, the present disclosure is not limited thereto. Nanostructures may also take other forms of structures, all such variations are within the scope of this disclosure.
  • the size and shape of the microstructure unit are determined according to the working band of the laser radar. That is to say, the working wavelength bands of the first hyperlens 102 and the second hyperlens 103 are commonly used wavelength bands of lidar, including 850nm, 905nm, 940nm, 1550nm and so on. According to an embodiment of the present disclosure, air or other materials that are transparent or translucent in the working wavelength band may be filled between the nanostructures. According to an embodiment of the present disclosure, the absolute value of the difference between the refractive index of the filled material and the refractive index of the nanostructure should be greater than or equal to 0.5.
  • the first metalens 102 can compress the initial beam L 0 with the initial divergence angle ⁇ 0 emitted by the laser surface light source 101 into the first beam L 1 with the first divergence angle ⁇ 1 .
  • the ratio between the first divergence angle ⁇ 1 and the initial divergence angle ⁇ 0 is less than 1/5.
  • the phase on the first metalens 102 It may be to correct the aberration of the convergence phase of the second hyperlens 103 .
  • the laser surface light source 101 is disposed near the focal plane of the first metalens 102 .
  • the distance between the laser surface light source 101 and the first metalens 102 should be smaller than the focal depth of the first metalens 102 .
  • the depth of focus ⁇ f of the first hyperlens 102 can be determined by the following formula (1).
  • ⁇ c is the central wavelength of the laser beam
  • F is the F-number of the first hyperlens, calculated by dividing the focal length of the first hyperlens 102 by the aperture of the first hyperlens 102 .
  • the second metalens 103 can further compress the first light beam L1 having the first divergence angle ⁇ 1 transmitted through the first metalens 102 into a second beam L1 having the second divergence angle ⁇ 2.
  • Beam L 2 .
  • the second light beam L 2 is used to generate a point cloud or a multi-line at the far field, so the second divergence angle ⁇ 2 should satisfy the following formula (2).
  • L is the farthest working distance of the lidar
  • d is the minimum size of the target that can be detected at the farthest working distance L. That is to say, according to an embodiment of the present disclosure, the second divergence angle ⁇ 2 is determined by the furthest working distance of the lidar and the smallest size of an object detectable at the furthest working distance.
  • the farthest working distance L is much larger than the minimum size d of the target that can be detected at the farthest working distance L, so the second divergence angle ⁇ is extremely small (approximately zero, so it is not shown in Fig. 1), so that The second light beam L 2 is approximately parallel light.
  • the second metalens 103 has the function of compressing and collimating light beams.
  • the phase required for the function of the second hyperlens 103 to compress the divergence angle of the laser beam is The corresponding phase can be calculated by inversely deriving the incident parallel light with the maximum field angle at the far field focused on the laser surface light source 101
  • the second metalens 103 also has the function of generating point clouds or multi-lines at the far field. Specifically, the laser beams emitted by the laser source array at different positions in the laser surface light source 101 are added to generate a point cloud or a multi-line phase at the far field.
  • the phase on the second hyperlens 103 It can be calculated by the following formula (3).
  • mod() is the remainder function. Can be given by point cloud or multi-line pattern combined with GS algorithm as phase recovery method. Since the phase control method of lidar is known to those skilled in the art, its details will not be described in more detail herein.
  • point clouds or multilines can be generated at the far field by adjusting the phase of the initial beam.
  • the aperture of the second hyperlens 103 is smaller than the aperture of the first hyperlens 102 .
  • This is determined by the functions of the first hyperlens 102 and the second hyperlens 103 .
  • the first metalens 102 directly faces the laser surface light source 101, and is used to compress the initial beam L 0 with a relatively large initial divergence angle ⁇ 0 into a first beam L 1 with a first divergence angle ⁇ 1 , considering From the size of the initial divergence angle ⁇ 0 , the distance between the laser surface light source 101 and the first metalens 102 , and the plane size of the laser surface light source 101 , the first metalens 102 has a larger aperture.
  • the second metalens 103 is used to further compress the first divergence angle ⁇ 1 into a second divergence angle ⁇ 2 and generate point clouds or multilines at the far field. Therefore, as shown in Figure 1, after the light beam passes through the first hyperlens 102, the laser beams emitted by the laser source arrays at different positions on the laser surface light source 101 need to be converged to the same position, so the second hyperlens 103 The aperture is smaller than the aperture of the first metalens 102 .
  • first hyperlens 102 and the second hyperlens 103 are shown in FIG.
  • the structural layers all face the laser surface light source 101, but the present disclosure is not limited thereto.
  • 6A to 6C show schematic diagrams of configurations of a transmitter 100 for lidar according to alternative embodiments of the present disclosure. As shown in FIGS. 6A to 6C , the orientations of the microstructure layers of the first hyperlens 102 and the second hyperlens 103 can be set arbitrarily, and all such variations are within the scope of the present disclosure.
  • the present disclosure also provides a lidar, which includes the above-mentioned transmitter.
  • FIG. 7 shows a schematic diagram of a configuration of a transmitter 700 for lidar according to an example of the present disclosure.
  • the working band of the transmitter 700 in this example is at 905nm, that is, it emits a laser beam with a center wavelength of 905nm.
  • the far-field structure is a point cloud or a multi-line combination.
  • the diagonal length of the laser surface light source 701 is 11.5 mm, and the distance between the laser surface light source 701 and the first hyperlens 702 is 7.3 mm.
  • the diameter of the first hyperlens 702 is 17 mm, and the diameter of the second hyperlens 703 is 7 mm.
  • Figure 8A shows the relationship between focal plane spot size and field of view angle when point cloud phase is not considered. As shown in Fig. 8A, the maximum light spot is 33 ⁇ m, which is smaller than the design requirement of 100 ⁇ m.
  • Figure 8B shows a graph of the modulation transfer function corresponding to Figure 8A.
  • FIG. 9A shows a phase diagram of a first metalens 702 according to an example of the present disclosure
  • FIG. 9B shows a phase diagram of a second metalens 703 according to an example of the present disclosure
  • FIG. 9C shows a phase diagram of a second metalens 703 according to an example of the present disclosure.
  • Simulation diagram of the disclosed example projecting a point cloud of 256 points at the far field.
  • FIG. 10 is a graph showing the relationship between the transmittance and the phase of the square nanopillars at a working wavelength band of 905 nm and the side length of the square nanopillars according to an example of the present disclosure.
  • the phases of the first hyperlens 702 and the second hyperlens 703 shown in FIG. 9A and FIG. 9B considering the data of nanostructures in the superlens under the working wavelength band of 905 nm as shown in FIG. 10 , it can be obtained according to different positions
  • the corresponding nanostructures are set at the phase at , so as to obtain the entire processing layout of the first superlens 702 and the second superlens 703, wherein the microstructure units of the first superlens 702 and the second superlens 703 all have a square period, and the side length It is 450nm, and the substrate material is quartz glass.
  • the material of the nanostructure is amorphous silicon, and the nanostructure is a nano-square column with a side length ranging from 100nm to 350nm and a column height of 600nm.
  • the filling material between the nano-square columns is silane, covering the phase from 0 to 2 ⁇ , and the average The transmittance is greater than 95.6%.
  • a metalens can be used to simultaneously realize the function of generating far-field point cloud or multi-line and the function of beam collimation, thereby reducing the The number of lenses, which can reduce the overall volume, weight and cost of lidar.
  • a laser surface light source composed of a laser source array can be used to realize a non-mechanical scanning transmitter, thereby reducing the complexity of the transmitter At the same time, the overall service life of the lidar is improved.

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Abstract

本公开提供了用于激光雷达的发射器和激光雷达。根据本公开的发射器包括：激光面光源，发射具有初始发散角的初始光束；第一超透镜，初始光束通过第一超透镜，使得具有初始发散角的初始光束被变换为具有第一发散角的第一光束；第二超透镜，第一光束通过第二超透镜，使得具有第一发散角的第一光束被变换为具有第二发散角的第二光束，第二光束用于在远场处产生点云或多线，其中，第一超透镜位于第二超透镜和激光面光源之间，以及其中，第一发散角小于初始发散角，并且第二发散角小于第一发散角。根据本公开的用于激光雷达的发射器和包括其的激光雷达具有结构简单、体积小、成本低、寿命长等优点。

Description

用于激光雷达的发射器和激光雷达 技术领域
本公开涉及光学超透镜的技术领域，具体地，本公开涉及用于激光雷达的发射器和激光雷达。
背景技术
激光雷达是一种采用非接触激光测距技术的扫描式传感器，其工作原理与一般的雷达系统类似，即通过发射激光光束来探测目标，并通过搜集反射回来的光束来形成点云和获取数据，这些数据经光电处理后可生成为精确的三维立体图像。采用这项技术，可以准确的获取高精度的物理空间环境信息，测距精度可达厘米级。因此，激光雷达在汽车自动驾驶、精密建模以及三维遥感等科学和工业领域中作为基本元器件有着极为广泛的应用。
激光雷达主要由发射器、接收器、信号处理单元和显示单元构成。进一步地，发射器主要包括激光源、光学调制模块、波束控制模块和扫描控制模块。具体地，激光源发射的激光在通过光学调制模块和波束控制模块进行光学调制和波束控制之后，在扫描控制模块的控制下投射到空间中，使得激光束按照特定的方式在空间中扫描。当激光束照射到目标时，发生散射现象，而散射回来的光电信号由激光雷达的接收器接收，随后由信号处理单元转换为电信号并进行放大和信息处理，从而在显示单元上显示目标信号。
传统的激光雷达的发射器的扫描控制模块主要使用机械式扫描模块和MEMS微震镜扫描模块来实现。然而，非机械扫描式的激光雷达的发射器由于不具备旋转组件而在一定程度降低了硬件成本和磨损消耗，并且在光源阵列中的个别器件损坏的情况下仍可持续工作，使 得在可靠性上实现了极大提升，因此已得到广泛的关注。
超透镜是一种通过半导体工艺制造的平面透镜，具有体积小(厚度薄)、重量轻、结构简单、成本低、产能高等优点。由于上述优点，超透镜也可以用在激光雷达的发射器中。然而，在现有技术中，超透镜在激光雷达的发射器中仅被用于准直激光，而多线的产生仍然需要按预定取向排列的多个激光光源，而且远场点云的产生仍需要衍射光学元件，这样并不能发挥上文所述的超透镜的优点。
因此，仍需要一种能够充分发挥超透镜的优点的非机械扫描式的激光雷达的发射器。
发明内容
在下文中给出了关于本公开的简要概述，以便提供关于本公开的某些方面的基本理解。但是，应当理解，此概述并非关于本公开的穷举性概述，也非意在确定本公开的关键性部分或重要部分，更非意在限定本公开的范围。此概述的目的仅在于以简化的形式给出关于本公开的某些发明构思，以此作为稍后给出的更详细的描述的前序。
本公开的目的在于提供基于超透镜的用于激光雷达的发射器和使用该发射器的激光雷达。
根据本公开的一个方面，提供了一种用于激光雷达的发射器，其包括：激光面光源，发射具有初始发散角的初始光束；第一超透镜，初始光束通过第一超透镜，使得具有初始发散角的初始光束被变换为具有第一发散角的第一光束；第二超透镜，第一光束通过第二超透镜，使得具有第一发散角的第一光束被变换为具有第二发散角的第二光束，第二光束用于在远场处产生点云或多线，其中第一超透镜位于第二超透镜和激光面光源之间，以及其中第一发散角小于初始发散角，并且第二发散角小于第一发散角。
根据本公开的实施方式，第一发散角与初始发散角之间的比率小于1/5。
根据本公开的实施方式，第二发散角由激光雷达的最远工作距离和在最远工作距离处可探测的目的的最小尺寸确定。
根据本公开的实施方式，激光面光源包括多个激光源阵列，每个激光源阵列由多个激光源构成。
根据本公开的实施方式，多个激光源阵列按预定顺序依次点亮。
根据本公开的实施方式，多个激光源阵列随机地点亮。
根据本公开的实施方式，在多个激光源阵列中，对应于中心视场的激光源阵列的点亮次数大于对应于中心视场外部的激光源阵列的点亮次数。
根据本公开的实施方式，第一超透镜和第二超透镜中的每个包括基板和设置在基板上的微结构层，以及其中微结构层包括布置成阵列的微结构单元。
根据本公开的实施方式，微结构单元的尺寸和形状根据激光雷达的工作波段确定。
根据本公开的实施方式，通过调整初始光束的相位在远场处产生点云或多线。
根据本公开的另一方面，提供了一种激光雷达，其包括根据本公开的上述方面的发射器。
根据本公开的技术方案，可以使用一个超透镜同时实现产生远场点云或多线的功能以及光束准直的功能，从而减少了发射器中的透镜的数量，从而可以减小激光雷达的整体体积、重量和成本。此外，根据本公开的技术方案，可以使用由激光源阵列构成的激光面光源实现非机械扫描式的发射器，从而在降低发射器的复杂度的同时提高了激光雷达的整体使用寿命。
附图说明
所包括的附图用于提供本公开的进一步理解，并且被并入本说明书中构成本说明书的一部分。附图示出了本公开的实施方式，连同下 面的描述一起用于说明本公开的原理。
图1示出了根据本公开的实施方式的用于激光雷达的发射器的配置的示意图。
图2示出了根据本公开的实施方式的激光面光源的平面视图。
图3A至图3D示出了根据本公开的实施方式的激光面光源中包括的激光源阵列依次点亮的示例的示意图。
图4A和图4B示出了根据本公开的实施方式的第一超透镜和第二超透镜的一个微结构单元的透视图。
图5A和图5B示出了根据本公开的实施方式的第一超透镜和第二超透镜的微结构层的平面视图。
图6A至图6C示出了根据本公开的替选实施方式的用于激光雷达的发射器的配置的示意图。
图7示出了根据本公开的示例的用于激光雷达的发射器700的配置的示意图。
图8A示出了在不考虑点云相位时焦平面光斑大小与视场角度之间的关系。
图8B示出了与图8A对应的调制传递函数的曲线图。
图9A示出了根据本公开的示例的第一超透镜的相位图，图9B示出了根据本公开的示例的第二超透镜的相位图，并且图9C示出了根据本公开的示例的在远场处投影256个点的点云的仿真图。
图10示出了根据本公开的示例的纳米方柱在905nm的工作波段下的透射率和相位与纳米方柱的边长之间的关系的曲线图。
具体实施方式
现将在下文中参照附图更全面地描述本公开，在附图中示出了各实施方式。然而，本公开可以以许多不同的方式实施，并且不应被解释为限于本文阐述的实施方式。相反，这些实施方式被提供使得本公开将是详尽的和完整的，并且将向本领域技术人员全面传达本公开的 范围。通篇相同的附图标记表示相同的部件。再者，在附图中，为了清楚地说明，部件的厚度、比率和尺寸被放大。
本文使用的术语仅用于描述具体实施方式的目的，而非旨在成为限制。除非上下文清楚地另有所指，否则如本文使用的“一”、“一个”、“该”和“至少之一”并非表示对数量的限制，而是旨在包括单数和复数二者。例如，除非上下文清楚地另有所指，否则“一个部件”的含义与“至少一个部件”相同。“至少之一”不应被解释为限制于数量“一”。“或”意指“和/或”。术语“和/或”包括相关联的列出项中的一个或更多个的任何和全部组合。
除非另有限定，否则本文使用的所有术语，包括技术术语和科学术语，具有与本领域技术人员所通常理解的含义相同的含义。如共同使用的词典中限定的术语应被解释为具有与相关的技术上下文中的含义相同的含义，并且除非在说明书中明确限定，否者不在理想化的或者过于正式的意义上将这些术语解释为具有正式的含义。
“包括”或“包含”的含义指明了性质、数量、步骤、操作、部件、部件或它们的组合，但是并未排除其他的性质、数量、步骤、操作、部件、部件或它们的组合。
本文参照作为理想化的实施方式的截面图描述了实施方式。从而，预见到作为例如制造技术和/或公差的结果的、相对于图示的形状变化。因此，本文描述的实施方式不应被解释为限于如本文示出的区域的具体形状，而是应包括因例如制造导致的形状的偏差。例如，被示出或描述为平坦的区域可以典型地具有粗糙和/或非线性特征。而且，所示出的锐角可以被倒圆。因此，图中所示的区域在本质上是示意性的，并且它们的形状并非旨在示出区域的精确形状并且并非旨在限制权利要求的范围。
在下文中，将参照附图描述根据本公开的示例性实施方式。
图1示出了根据本公开的实施方式的用于激光雷达的发射器100的配置的示意图。
如图1所示，根据本公开的用于激光雷达的发射器100包括：激 光面光源101，其发射具有初始发散角θ 0的初始光束L 0；第一超透镜102，初始光束L 0通过第一超透镜102，使得具有初始发散角θ 0的初始光束L 0被变换为具有第一发散角θ 1的第一光束L 1；第二超透镜103，第一光束L 1通过第二超透镜103，使得具有第一发散角θ 1的第一光束L 1被变换为具有第二发散角θ 2的第二光束L 2，第二光束L 2用于在远场处产生点云或多线，其中第一超透镜102位于第二超透镜103和激光面光源101之间，以及其中第一发散角L 1小于初始发散角L 0，并且第二发散角θ 2小于第一发散角θ 1。如下文将进一步详细描述的，第二发散角θ 2极小，接近于零度，即第二光束L 2近似于平行光，因此在图1中未明确标出第二发散角θ 2的具体位置。
图2示出了根据本公开的实施方式的激光面光源101的平面视图。
根据本公开的实施方式，激光面光源101包括多个激光源阵列，每个激光源阵列由多个激光源构成。
具体地，如图2所示，激光面光源101可以具有激光源阵列的形式。根据本公开的实施方式，激光面光源101可以包括结构相同的N个激光源阵列101-i，其中1≤i≤N。优选地，N为大于1的自然数的平方数，例如4、9、16、25等。例如，图2中的激光面光源101包括5×5(即N＝25)个激光源阵列101-1至101-25。根据本公开的实施方式，每个激光源阵列由多个激光源构成。
根据本公开的实施方式，每个激光源阵列可以包括结构相同的M个激光源，其中M是大于1的自然数。例如，如图2中所示，每个激光源阵列可以包括例如4×4(即M＝16)个激光源。根据本公开的实施方式，每个激光源阵列101-i也可以包括数目更多或更少的激光源。尽管在图2中每个激光源阵列101-i中的激光源被示出为以正方形的形式布置，但是本公开不限于此，每个激光源阵列101-i中的激光源也可以以正六边形的形式布置，或者以具有空间对称性的其他形状的形式布置。
如图1中所示，激光面光源101发射的激光经过第一超透镜102和第二超透镜103的压缩和准直在远场处产生点云或多线。由于激光 面光源101上位于不同位置的激光源对应于第二超透镜103处的不同的出射角度，进而对应于远场处的不同的视场角度，因此位于激光面光源101的非中心视场处的激光源发射的激光束对应于斜出射的远场平行光以及相应的点云或多线。例如，如图1所示，激光面光源101的视场中心位置1处的激光源发射的激光在经过第二超透镜103之后相对于与激光面光源101垂直的方向的视场角度为0直。激光面光源101的偏离视场中心的位置2处的激光源发射的激光在经过第二超透镜103之后相对于与激光面光源101垂直的方向的视场角度为15°。此外，激光面光源101的远离视场中心的位置3处的激光源发射的激光在经过第二超透镜103之后相对于与激光面光源101垂直的方向的视场角度为30°。
因此，根据本公开的实施方式，激光面光源101中包括的多个激光源阵列101-i依次点亮。换言之，由于激光面光源101的非中心视场的激光源对应于斜出射的远场平行光和相应的点云或多线，因此可以使用激光面光源101中包括的激光源阵列依次点亮的方式在远场处进行扫描。
图3A至图3D示出了根据本公开的实施方式的激光面光源101中包括的激光源阵列101-i点亮的示例的示意图。
根据本公开的实施方式，多个激光源阵列101-i按预定顺序依次点亮。如图3A中的箭头所示，激光源阵列101-i可以在水平方向上按照S形的方式依次点亮。根据本公开的实施方式，如图3B中的箭头所示，激光源阵列101-i可以在竖直方向上按照S形的方式依次点亮。根据本公开的实施方式，如图3C中的箭头所示，激光源阵列101-i可以从视场的中心位置处的激光源阵列开始上按照向外的螺旋形的方式依次点亮。在全部激光源阵列101-i中的每一个点亮一次之后，完成一个扫描周期，随后开始下一个扫描周期。
本领域技术人员应认识到，激光面光源101中包括的激光源阵列101-i的点亮方式，即扫描方式不限于图3A至图3C中所示的示例，根据本公开的实施方式，激光源阵列101-i也可以以其他设定的顺序 依次点亮。
此外，根据本公开的实施方式，多个激光源阵列101-i还可以随机地点亮。具体地，在一个扫描周期中，多个激光源阵列101-i可以按照随机的顺序被点亮，只要多个激光源阵列101-i中的每一个被点亮一次即可。在全部激光源阵列101-i中的每一个点亮一次之后，完成一个扫描周期，随后开始下一个扫描周期。
根据本公开的实施方式，在多个激光源阵列101-i中，对应于中心视场的激光源阵列的点亮次数大于对应于中心视场外部的激光源阵列的点亮次数。如图3D所示，激光面光源103中包括的激光源阵列101-i中的对应于中心视场区域的激光源阵列由虚线框标出。为了保证激光雷达对前方中心视场有足够的刷新频率，因此在每个扫描周期内，中心视场需要多次被扫描到。因此，根据本公开的实施方式，可以在每个扫描周期中将中心视场外(虚线框外)的激光源阵列的点亮次数设定为1，而将中心视场内(虚线框内)的激光源阵列的点亮次数设定为m，其中m是大于或等于2的自然数。根据本公开的实施方式，在每个扫描周期中，可以按照预先设定的顺序点亮激光源阵列101-i，其中中心视场外的激光源阵列仅被点亮1次，而中心视场内的激光源阵列被点亮m次。这种不同位置的激光源阵列的不同点亮次数(频率)的扫描方式可以保证激光雷达对前方中心视场有足够的刷新频率。
根据本公开的实施方式，激光面光源101中包括的多个激光源阵列101-i也可以随机地点亮，只要对应于中心视场的激光源阵列的点亮次数大于对应于中心视场外部的激光源阵列的点亮次数即可，这样可以减少依次点亮激光源阵列的过程中可能带来的相近视场下点云数据的串扰问题。
接下来对根据本公开的实施方式的第一超透镜102和第二超透镜103进行更详细的描述。
超透镜是超表面的一种具体应用。超表面是一层亚波长的人工纳米结构膜，可根据其上的超表面微结构单元来调制入射光。超表面的微结构单元包含全介质或等离子的纳米天线，可直接调控光的相位、 幅度和偏振等特性。
图4A和图4B示出了根据本公开的实施方式的第一超透镜102和第二超透镜103的一个微结构单元的透视图。图5A和图5B示出了根据本公开的实施方式的第一超透镜102和第二超透镜103的微结构层的平面视图。
如图4A和图4B所示，根据本公开的实施方式，第一超透镜102和第二超透镜103中的每个包括基板和设置在基板上的微结构层，其中微结构层包括布置成阵列的微结构单元。
如图5A所示，根据本公开的实施方式，微结构单元可以布置成正六边形的阵列。此外，如图5B所示，根据本公开的实施方式，微结构单元可以布置成正方形的阵列。本领域技术人员应认识到，微结构层中包括的微结构单元还可以包括其他形式的阵列布置，所有这些变型方案均涵盖于本公开的范围内。
根据本公开的实施方式，微结构单元可以具有纳米结构。如图4A和图4B所示，根据本公开的实施方式，每个微结构单元的中心位置和/或顶点位置处分别设置有纳米结构。根据本公开的实施方式，纳米结构是全介质结构单元。根据本公开的实施方式，纳米结构在近红外光波段具有高透射率。根据本公开的实施方式，纳米结构可由如下材料中的至少之一形成：氧化钛、氮化硅、熔融石英、氧化铝、氮化镓、磷化镓、非晶硅、晶体硅和氢化非晶硅等。
超透镜的微结构单元中的纳米结构可以具有纳米柱的形式。尽管图4A中所示的纳米柱的截面是圆形，并且图4B中所示的纳米柱的截面是正方形，但是本公开不限于此。纳米结构还可以采用其他形式的结构，所有这些变型方案均涵盖于本公开的范围内。
根据本公开的实施方式，微结构单元的尺寸和形状根据激光雷达的工作波段确定。也就是说，第一超透镜102和第二超透镜103的工作波段为激光雷达常用的波长波段，包括850nm、905nm、940nm、1550nm等。根据本公开的实施方式，各纳米结构之间可以填充空气或者在工作波段透明或半透明的其他材料。根据本公开的实施方式， 所填充的材料的折射率与纳米结构的折射率之间的差值的绝对值应大于等于0.5。
如图1中所示，第一超透镜102可以将激光面光源101发射的具有初始发散角θ 0的初始光束L 0压缩成具有第一发散角θ 1的第一光束L 1。根据本公开的实施方式，第一发散角θ 1与初始发散角θ 0之间的比率小于1/5。此外，根据本公开的实施方式，第一超透镜102上的相位
Figure PCTCN2022129832-appb-000001
可以为校正第二超透镜103的汇聚相位的像差。
此外，根据本公开的实施方式，激光面光源101设置在第一超透镜102的焦平面附近。具体地，根据本公开的实施方式，激光面光源101与第一超透镜102之间的距离应小于第一超透镜102的焦点深度。第一超透镜102的焦点深度Δf可以由下式(1)确定。
Δf＝±2λ cF 2          (1)
其中λ c是激光束的中心波长，F是第一超透镜的F数，通过第一超透镜102的焦距除以第一超透镜102的口径来计算。
此外，如图1中所示，第二超透镜103可以将透射通过第一超透镜102的具有第一发散角θ 1的第一光束L 1进一步压缩成具有第二发散角θ 2的第二光束L 2。根据本公开的实施方式，第二光束L 2用于在远场处产生点云或多线，因此第二发散角θ 2应满足下式(2)。
θ 2·L≤d         (2)
其中，L是激光雷达的最远工作距离，d是在最远工作距离L处能够探测的目标的最小尺寸。也就是说，根据本公开的实施方式，第二发散角θ 2由激光雷达的最远工作距离和在最远工作距离处可探测的目的的最小尺寸确定。通常，最远工作距离L远大于在最远工作距离L处能够探测的目标的最小尺寸d，因此第二发散角θ 2极小(近似为零，因此未在图1中示出)，使得第二光束L 2近似于平行光。
如上文所述，第二超透镜103具有压缩和准直光束的功能。具体地，设第二超透镜103压缩激光束的发散角的功能所需的相位为
Figure PCTCN2022129832-appb-000002
可以通过逆向推导远场处的具有最大视场角度的平行光入射聚焦到激光面光源101来计算相应的相位
Figure PCTCN2022129832-appb-000003
此外，根据本公开的实施方式，第二超透镜103还具有在远场处产生点云或多线的功能。具体地，激光面光源101中的不同位置处的激光源阵列发射的激光束被添加用于在远场处产生点云或多线的相位
Figure PCTCN2022129832-appb-000004
综上所述，考虑到第二超透镜103的上述两个功能，第二超透镜103上的相位
Figure PCTCN2022129832-appb-000005
可以通过下式(3)来计算。
Figure PCTCN2022129832-appb-000006
其中，mod()为取余函数。
Figure PCTCN2022129832-appb-000007
可以由点云或者多线的图案结合作为相位恢复方法的G-S算法给出。鉴于激光雷达的相控方法对于本领域技术人员是已知的，因此本文不对其细节进行更详细的描述。
因此，根据本公开的实施方式，可以通过调整初始光束的相位在远场处产生点云或多线。
此外，根据本公开的实施方式，第二超透镜103的口径小于第一超透镜102的口径。这是由第一超透镜102和第二超透镜103的功能所决定的。具体地，第一超透镜102直接面对激光面光源101，用于将具有较大的初始发散角θ 0的初始光束L 0压缩成具有第一发散角θ 1的第一光束L 1，考虑到初始发散角θ 0的大小、激光面光源101与第一超透镜102之间距离以及激光面光源101的平面尺寸，第一超透镜102具有较大的口径。作为对比，第二超透镜103用于进一步将第一发散角θ 1压缩成第二发散角θ 2并且在远场处产生点云或多线。因此，如图1所示，光束在经过第一超透镜102之后，激光面光源101上的不同位置处的激光源阵列发射的激光束都需要汇聚到相同的位置，因此第二超透镜103的口径小于第一超透镜102的口径。
本领域技术人员应认识到，尽管图1中将第一超透镜102和第二超透镜103示出为它们的微结构层具有相同的取向，即第一超透镜102和第二超透镜103微结构层均面向激光面光源101，但是本公开不限 于此。图6A至图6C示出了根据本公开的替选实施方式的用于激光雷达的发射器100的配置的示意图。如图6A至图6C所示，第一超透镜102和第二超透镜103的微结构层的取向可以任意设置，所有这样的变型方案均涵盖于本公开的范围内。
此外，本公开还提供了一种激光雷达，其包括根据上文所述的发射器。
示例
图7示出了根据本公开的示例的用于激光雷达的发射器700的配置的示意图。
该示例的发射器700的工作波段在905nm处，即发射中心波长为905nm的激光束。该示例对光束准直的要求如下：有效口径6mm、焦距10mm、视场角度(FOV)＝60角，平行光入射到焦平面的光斑小于100μm为像差可接受标准。远场结构为点云或者多线组合。
据此，激光面光源701的对角线长度为11.5mm，激光面光源701与第一超透镜702之间的距离为7.3mm。第一超透镜702的直径为17mm，第二超透镜703的直径为7mm。本领域技术人员应认识到，本文所提及的透镜的“口径”和“直径”是两个不同的概念。具体地本文中的“口径”意指透镜的入瞳直径，而“直径”意指透镜的几何直径。
图8A示出了在不考虑点云相位时焦平面光斑大小与视场角度之间的关系。如图8A所示，最大光斑为33μm，小于设计要求的100μm。
图8B示出了与图8A对应的调制传递函数的曲线图。
此外，图9A示出了根据本公开的示例的第一超透镜702的相位图，图9B示出了根据本公开的示例的第二超透镜703的相位图，并且图9C示出了根据本公开的示例的在远场处投影256个点的点云的仿真图。
图10示出了根据本公开的示例的纳米方柱在905nm的工作波段下的透射率与相位和纳米方柱的边长之间的关系的曲线图。
根据图9A和图9B中示出的第一超透镜702和第二超透镜703的相位，考虑如图10所示的905nm的工作波段下的超透镜中的纳米结构的数据，可根据不同位置处的相位设置相应的纳米结构，从而得到第一超透镜702和第二超透镜703的整个加工版图，其中第一超透镜702和第二超透镜703的微结构单元均具有正方形周期，边长为450nm，基板材料为石英玻璃。纳米结构的材料为非晶硅，纳米结构为边长从100nm到350nm变化且柱高为600nm的纳米方柱，纳米方柱之间的填充材料为硅烷，覆盖从0到2π的相位，并且平均透射率大于95.6％。
根据本公开的用于激光雷达的发射器和包括该发射器的激光雷达，可以使用一个超透镜同时实现产生远场点云或多线的功能以及光束准直的功能，从而减少了发射器中的透镜的数量，从而可以减小激光雷达的整体体积、重量和成本。此外，根据本公开的用于激光雷达的发射器和包括该发射器的激光雷达，可以使用由激光源阵列构成的激光面光源实现非机械扫描式的发射器，从而在降低发射器的复杂度的同时提高了激光雷达的整体使用寿命。
尽管参照本公开的示例性实施方式描述了本公开，但是本领域技术人员将理解，在不偏离权利要求中阐述的本公开的精神和范围的情况下，可以进行各种修改和变化。

Claims (11)

  1. 一种用于激光雷达的发射器，包括：
    激光面光源，发射具有初始发散角的初始光束；
    第一超透镜，所述初始光束通过所述第一超透镜，使得具有所述初始发散角的所述初始光束被变换为具有第一发散角的第一光束；
    第二超透镜，所述第一光束通过所述第二超透镜，使得具有所述第一发散角的所述第一光束被变换为具有第二发散角的第二光束，所述第二光束用于在远场处产生点云或多线，
    其中，所述第一超透镜位于所述第二超透镜和所述激光面光源之间，以及
    其中，所述第一发散角小于所述初始发散角，并且所述第二发散角小于所述第一发散角。
  2. 根据权利要求1所述的发射器，其中，所述第一发散角与所述初始发散角之间的比率小于1/5。
  3. 根据权利要求1所述的发射器，其中，所述第二发散角由所述激光雷达的最远工作距离和在所述最远工作距离处可探测的目的的最小尺寸确定。
  4. 根据权利要求1所述的发射器，其中，所述激光面光源包括多个激光源阵列，每个激光源阵列由多个激光源构成。
  5. 根据权利要求4所述的发射器，其中，所述多个激光源阵列按预定顺序依次点亮。
  6. 根据权利要求4所述的发射器，其中，所述多个激光源阵列随机地点亮。
  7. 根据权利要求5或6所述的发射器，其中，在所述多个激光源阵列中，对应于中心视场的激光源阵列的点亮次数大于对应于中心视场外部的激光源阵列的点亮次数。
  8. 根据权利要求1所述的发射器，其中，所述第一超透镜和所述第二超透镜中的每个包括基板和设置在所述基板上的微结构层，以及
    其中，所述微结构层包括布置成阵列的微结构单元。
  9. 根据权利要求1所述的发射器，其中，所述微结构单元的尺寸和形状根据所述激光雷达的工作波段确定。
  10. 根据权利要求1所述的发射器，其中，通过调整所述初始光束的相位在远场处产生所述点云或多线。
  11. 一种激光雷达，包括根据权利要求1至10中任一项所述的发射器。
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JP2022542172A (ja) 2019-07-26 2022-09-29 メタレンズ，インコーポレイテッド アパーチャメタ表面およびハイブリッド屈折メタ表面イメージングシステム
CN113900078A (zh) * 2021-11-09 2022-01-07 深圳迈塔兰斯科技有限公司 用于激光雷达的发射器和激光雷达
CN114637120A (zh) * 2022-03-31 2022-06-17 天津山河光电科技有限公司 一种多功能超表面分束器
US11927769B2 (en) 2022-03-31 2024-03-12 Metalenz, Inc. Polarization sorting metasurface microlens array device
CN114859446B (zh) * 2022-06-14 2023-06-02 深圳迈塔兰斯科技有限公司 复合超透镜及其形成方法和点阵投影系统

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108627982A (zh) * 2017-03-15 2018-10-09 中国科学院苏州纳米技术与纳米仿生研究所 光学系统及其光学装置
CN109669226A (zh) * 2019-01-07 2019-04-23 浙江大学 一种基于超表面透镜组阵列的激光雷达扫描装置及其设计方法
CN111090148A (zh) * 2019-12-06 2020-05-01 武汉大学 一种基于超表面透镜的多芯光纤复用和解复用装置及方法
CN213814260U (zh) * 2020-12-31 2021-07-27 杭州中科极光科技有限公司 一种激光光源及激光显示系统
CN214098104U (zh) * 2021-01-07 2021-08-31 深圳迈塔兰斯科技有限公司 一种3D-ToF模组
CN113900078A (zh) * 2021-11-09 2022-01-07 深圳迈塔兰斯科技有限公司 用于激光雷达的发射器和激光雷达

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107102503A (zh) * 2016-02-19 2017-08-29 中国科学院苏州纳米技术与纳米仿生研究所 消除激光散斑的光源系统以及投影装置
US11057115B1 (en) * 2020-09-30 2021-07-06 Visera Technologies Company Limited Optical communication device

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108627982A (zh) * 2017-03-15 2018-10-09 中国科学院苏州纳米技术与纳米仿生研究所 光学系统及其光学装置
CN109669226A (zh) * 2019-01-07 2019-04-23 浙江大学 一种基于超表面透镜组阵列的激光雷达扫描装置及其设计方法
CN111090148A (zh) * 2019-12-06 2020-05-01 武汉大学 一种基于超表面透镜的多芯光纤复用和解复用装置及方法
CN213814260U (zh) * 2020-12-31 2021-07-27 杭州中科极光科技有限公司 一种激光光源及激光显示系统
CN214098104U (zh) * 2021-01-07 2021-08-31 深圳迈塔兰斯科技有限公司 一种3D-ToF模组
CN113900078A (zh) * 2021-11-09 2022-01-07 深圳迈塔兰斯科技有限公司 用于激光雷达的发射器和激光雷达

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