A laser radar system and calibration method thereof

Abstract

The embodiment of the present invention discloses a laser radar system and a calibration method thereof, which relates to the field of laser radar technology and is invented to enable simple and quick calibration operations. The laser radar system includes: a laser emitting unit, a scanning unit, a receiving unit and a control unit; wherein the laser emitting unit includes a light source and a collimator located on the light emission path of the light source, the light source has more than two laser output channels, and the laser beams output by different laser output channels are all collimated by the collimator and then output in a divergent manner; and / or the receiving unit includes a photodetector, the photodetector has more than two pixels, and a converging lens is provided on the light receiving path of the more than two pixels, so that the more than two pixels receive the light reflected back by the target through a converging lens. The present invention is suitable for detecting the distance of a target.

Description

Technical Field

[0001] The present invention relates to the field of laser radar technology, and in particular to a laser radar system and a calibration method thereof. Background Art

[0002] Lidar is a radar system that emits laser beams to detect the position, speed and other characteristic quantities of a target. Its working principle is to emit a detection signal (laser beam) to the target, and then compare the received signal reflected from the target (target echo) with the emitted detection signal. After appropriate processing, relevant information about the target can be obtained, such as the target's distance, direction, height, speed, attitude, and even shape.

[0003] At present, the most widely used is the multi-line laser radar based on mechanical rotation scanning. A multi-line laser radar refers to a radar that emits multiple laser beams from a laser source and can generate multiple scanning lines in one scan. In a multi-line laser radar, a collimator needs to be configured for each laser beam in the laser emitting unit, and a converging lens needs to be configured for each target echo in the receiving unit. When calibrating the optical axes of the laser emitting unit and the receiving unit, since the number of laser beams emitted by the laser source is large, the number of collimators and converging lenses configured is also correspondingly large, making the calibration difficult and taking a long time. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a laser radar system and a calibration method thereof, which can perform calibration operations simply and quickly.

[0005] In a first aspect, an embodiment of the present invention provides a laser radar system, comprising: a laser emitting unit, a scanning unit, a receiving unit and a control unit, wherein the control unit controls the laser emitting unit to emit laser, and the laser is emitted after being scanned by the scanning unit so as to be received by the receiving unit after being reflected by a target; wherein the laser emitting unit comprises a light source and a collimator located on a light emission path of the light source, the light source has more than two laser output channels, and laser beams output by different laser output channels are all collimated by the collimator and then output in a divergent manner; and / or the receiving unit comprises a photodetector, the photodetector has more than two pixels, and a converging lens is provided on the light receiving path of the more than two pixels, so that the more than two pixels receive light reflected back by the target through a converging lens.

[0006] According to a specific implementation manner of the embodiment of the present invention, the light source and the collimator are connected together and can rotate together to calibrate the optical axes of the laser emitting unit and the receiving unit.

[0007] According to a specific implementation manner of the embodiment of the present invention, the photoelectric detector can move and / or rotate relative to the converging lens to calibrate the optical axes of the laser emitting unit and the receiving unit.

[0008] According to a specific implementation manner of the embodiment of the present invention, the photodetector and the converging lens can move and / or rotate together to calibrate the optical axes of the laser emitting unit and the receiving unit.

[0009] According to a specific implementation manner of the embodiment of the present invention, the laser emitted by the light source is a pulsed laser; and the outlets of the two or more laser output channels are linearly arranged in a vertical direction.

[0010] According to a specific implementation of an embodiment of the present invention, different light beams output by the collimator have a beam angle in the vertical direction; the scanning angle of the scanning unit in the vertical direction is less than the smallest angle among the beam angles. The light beams output by the collimator are provided with a fixed angle, and the angles between different light beams are in the vertical direction by adjusting the rotation direction of the collimator along the optical axis. After adjustment, the collimator is fixed with a clamping member of the collimator.

[0011] According to a specific implementation manner of the embodiment of the present invention, the scanning angle of the scanning unit in the vertical direction is adjustable.

[0012] According to a specific implementation manner of the embodiment of the present invention, the number of the picture elements is the same as the number of the laser output channels, and the more than two picture elements correspond one-to-one to the more than two laser output channels.

[0013] In a second aspect, an embodiment of the present application further provides a calibration method that can be used for any of the aforementioned laser radar systems, the calibration method comprising:

[0014] Rotate the light source together with the collimator to adjust the position where the light beam output by the collimator is incident on the scanning unit; and / or,

[0015] The positions of the two or more picture elements relative to the converging lens are adjusted, or the two or more picture elements are rotated or moved together with the converging lens, so that the light beam emitted after being scanned by the scanning unit is accurately received by the receiving unit after being reflected by the target.

[0016] According to a specific implementation of an embodiment of the present invention, different light beams output by the collimator have a beam angle in the vertical direction; the calibration method also includes: adjusting the scanning angle of the scanning unit in the vertical direction so that the scanning angle is smaller than the smallest angle among the beam angles.

[0017] In the laser radar system and calibration method provided by the embodiments of the present invention, two or more pulsed lasers emitted by the laser emitting unit are collimated and outputted through only one collimator, and / or only one converging lens is configured on the light receiving paths of more than two picture elements of the receiving unit, thereby greatly reducing the number of required collimators and / or converging lenses. In this way, when calibrating the optical axis between the laser emitting unit and the receiving unit, the complexity of the operation can be reduced, making the calibration operation simpler and faster. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of a laser radar system according to an embodiment of the present application.

[0020] Figure 2 Schematic diagram of the end face of the optical fiber head of the optical fiber laser in one embodiment of the present application.

[0021] Figure 3 Schematic diagram of a laser transmitter that integrates a fiber laser and a collimator.

[0022] Figure 4 Schematic diagram of an APD photodetector in one embodiment of the present application.

[0023] Figure 5 It is a schematic diagram of a receiving unit receiving a pulsed laser in one embodiment of the present application.

[0024] Figure 6 This is a schematic diagram of laser emitting by a laser radar system in one embodiment of the present application.

[0025] Figure 7 Schematic diagram of the scanning trajectory of the laser radar system in one embodiment of the present application. DETAILED DESCRIPTION

[0026] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It should be clear that the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] The embodiments of the present application aim to provide a laser radar system and a calibration method thereof that can perform calibration operations simply and quickly.

[0028] Figure 1 This is a schematic diagram of a laser radar system according to an embodiment of the present application. Figure 1 The laser radar system 100 of this embodiment includes: a laser emitting unit 200, a scanning unit 300, a receiving unit 400 and a control unit 500. The control unit 500 controls the laser emitting unit 200 to emit laser. The laser emitted by the laser emitting unit 200 is emitted after being scanned by the scanning unit 300 so as to be received by the receiving unit 400 after being reflected by the target.

[0029] The laser emitting unit 200 is used to generate pulsed laser and collimate the pulsed laser for output. It may include a light source and a collimator located on the light output path of the light source. The light source has more than two laser output channels. The laser beams output by different laser output channels are collimated by a collimator for output. Each laser beam is output through an optical fiber. Multiple optical fibers corresponding to multiple laser beams are connected to an optical fiber output connector. The optical fiber head is connected to a collimator to realize the collimated output of multiple light beams.

[0030] The light source may be a semiconductor light source, a fiber-coupled light source, or other types of light sources. In terms of wavelength, the light source may be a light source with a wavelength of 905 nm, 1550 nm, or other wavelengths. In one example, the light source is a narrow pulse laser fiber laser with a wavelength of 1550 nm.

[0031] The light source can emit more than two pulsed laser beams. The light source emits more than two pulsed laser beams, which are output through different laser output channels.

[0032] In one example, the light source includes a light source. The light source can emit a pulsed laser beam. The pulsed laser beam is split into two or more pulsed laser beams by a beam splitting device (such as a beam splitter). The two or more pulsed laser beams obtained after beam splitting are output through different laser output channels.

[0033] In another example, the light source includes more than two light sources. Each light source can emit a pulsed laser beam, and accordingly, the more than two light sources can simultaneously emit more than two pulsed laser beams. The more than two pulsed laser beams emitted simultaneously by the more than two light sources are output through different laser output channels.

[0034] When the light source includes more than two light sources, the spacing between the light sources is specifically arranged. In one embodiment, the spacing between the light sources is fixed, for example, 100-300 microns, and arranged in a straight line, triangle or rectangle.

[0035] In order to make the laser radar system 100 have a higher vertical resolution (also called vertical angular resolution), the outlets of more than two laser output channels of the laser emitting unit 200 can be arranged linearly in the vertical direction (such as the vertical direction), so that the scanning unit 300 can form more scanning tracks in the vertical direction, thereby increasing the vertical resolution of the laser radar system 100. The vertical resolution refers to the angular resolution of adjacent light rays in the vertical direction. The vertical resolution is less than or equal to the scanning angle. Figure 7 The vertical resolution of the top and bottom of the trajectory diagram formed by the mid-scan is equal to the scanning angle, and the vertical resolution of the middle part will be smaller than the scanning angle due to the interlaced superposition of the two channel trajectories.

[0036] In order to ensure that the laser radar system 100 has a high vertical resolution without excessively increasing the size of the light source in the vertical direction, the two or more pulsed laser beams emitted by the light source are collimated by a collimator and then output in a divergent manner, so that the different light beams output by the collimator have a preset beam angle in the vertical direction, and the beam angle is greater than 0.5 degrees and less than 5 degrees.

[0037] Accordingly, the scanning angle of the scanning unit 300 in the vertical direction is smaller than the smallest beam angle among the beam angles. Thus, the middle portion of the scanning trajectory diagram formed by the scanning unit 300 has a higher vertical resolution than the top and bottom portions.

[0038] The scanning angle of the scanning unit 300 in the vertical direction can be adjusted dynamically to achieve dynamic adjustment of the vertical resolution of the laser radar system 100. Specifically, the control unit 500 can dynamically adjust the vibration amplitude of the galvanometer corresponding to each line in the scanning unit 300 to dynamically adjust the scanning line angle of the scanning unit 300 in the vertical direction, thereby dynamically adjusting the vertical resolution of the laser radar system 100.

[0039] The scanning unit 300 includes a multi-faceted prism and a galvanometer. The multi-faceted prism is used to realize horizontal scanning, and the galvanometer is used to realize vertical scanning. The combination of the multi-faceted prism and the galvanometer can realize horizontal and vertical scanning detection of the laser radar system 100. Among them, the galvanometer can be a galvanometer driven by a motor or a galvanometer driven by a MEMS (micro-electromechanical system); the prism can be a prism with multiple reflective surfaces such as 2, 3, 4, or 6 surfaces.

[0040] The receiving unit 400 includes a photodetector, which has more than two pixels. A converging lens is provided on the light receiving path of the more than two pixels so that the more than two pixels receive the light reflected back by the target through a converging lens. The photodetector can be a photodetector made of different materials such as silicon-based and InGaAs. It can be a PIN photodetector, an APD (Aualanche Photo Diode) photodetector (also called an avalanche photodetector), a Geiger mode photodetector, and other types of photodetectors. In terms of the number and arrangement of pixels, the photodetector can be a linear photodetector or a planar array photodetector. The spacing between each pixel of the photodetector is specifically arranged. In one embodiment, the arrangement of the pixels of the photodetector is a linear arrangement or a planar array arrangement, and the spacing between each pixel can be a fixed and equal spacing, for example, 500-1000 microns.

[0041] In order to make the laser detection of the laser radar system 100 have a higher accuracy, when the light source (or the port of the laser output channel) of the laser emitting unit 200 is arranged in a linear array or a planar array, the pixels of the photodetector of the corresponding receiving unit 400 are also arranged in a linear array or a planar array, and each light source (or laser output channel) corresponds to each pixel one by one. For example, there are two laser output channels of the light source in the laser emitting unit 200, namely L1 and L2; there are also two pixels on the photodetector, namely R1 and R2, R1 corresponds to L1, and R2 corresponds to L2. The laser beam emitted from the L1 channel and collimated by the collimator is emitted toward the target after being scanned by the scanning unit 300, and is received by the pixel R1 after being reflected by the target; the laser beam emitted from the L2 channel and collimated by the collimator is emitted toward the target after being scanned by the scanning unit 300, and is received by the pixel R2 after being reflected by the target.

[0042] The receiving unit 400 may also include a signal conditioning circuit for processing the pulse echo received by the photodetector and reflected by the target and converged by the converging lens, such as performing noise removal or signal enhancement processing. The pulse echo processed by the signal conditioning circuit is output to the control unit 500, and the control unit 500 calculates the target distance according to the time that the pulse echo lags behind the transmitted pulse.

[0043] The control unit 500 is used to control the laser emitting unit 200 to emit pulsed laser, and then control the scanning unit 300 to scan and detect the target, and finally realize the point cloud display of the laser radar by reading the echo signal of the receiving unit 400 and calculating the distance. The control unit 500 can also be used to calculate the intensity information of the echo signal returned by the target.

[0044] When the laser radar system 100 starts working, the control unit 500 controls the laser emitting unit 200 to emit a pulsed laser, which is reflected by the galvanometer and the multi-faceted prism and then emitted toward the target. After being reflected by the target, the pulsed laser is received by the photoelectric detector of the receiving unit 400 along the prism and the galvanometer and generates an echo signal. The echo signal is processed by the signal conditioning circuit of the receiving unit 400 and then output to the control unit 500. The control unit 500 calculates the target distance based on the time that the pulse echo lags behind the emitted pulse. At the same time, the control unit 500 can obtain the angle data of the galvanometer and the prism in real time, and the three-dimensional point cloud information of the target can be obtained after solving. Through continuous scanning of the galvanometer and the prism, the control unit 500 can solve the point cloud information of the target in real time, and finally send it to the host computer to display the point cloud data of the target in real time.

[0045] The optical axis between the laser emitting unit 200 and the receiving unit 400 can be calibrated by changing the positions of the light source and the collimator, so that the laser beam emitted by the laser emitting unit 200 is emitted toward the target after being scanned by the scanning unit 300, and is accurately received by the receiving unit 400 after being reflected by the target. Specifically, the optical axis of the light source or the collimator can be used as the rotation axis, and the light source and the collimator can be rotated, or the light source and the collimator can be moved in three-dimensional space to calibrate the optical axis of the laser emitting unit 200 and the receiving unit 400.

[0046] Compared with configuring a collimator for each pulse laser beam, in this embodiment, more than two pulse laser beams are collimated and output through only one collimator. In this way, when calibrating the optical axis between the laser emitting unit 200 and the receiving unit 400, the complexity of the operation can be reduced, making the calibration operation simpler and faster.

[0047] To further simplify the calibration operation, the light source and the collimator can be adjusted as a whole. In one example, the collimator and the light source are connected (or integrated) together so that the light source and the collimator can be adjusted as a whole.

[0048] In addition to calibrating the optical axis between the laser emitting unit 200 and the receiving unit 400 by changing the position of the light source and the collimator, the optical axis between the laser emitting unit 200 and the receiving unit 400 can also be calibrated by changing the position of the photodetector and / or the converging lens.

[0049] In one example, the photodetector can move and / or rotate relative to the converging lens to calibrate the optical axes of the laser emitting unit 200 and the receiving unit 400, so that the laser beam emitted by the laser emitting unit 200 is emitted toward the target after being scanned by the scanning unit 300, and is accurately received by the receiving unit 400 after being reflected by the target. The movement of the photodetector relative to the converging lens can be a movement in three-dimensional space (approaching or moving away, moving left and right, moving up and down, etc.). The rotation of the photodetector relative to the converging lens can be a rotation made with the optical axis of the converging lens as the rotation axis.

[0050] In another example, the photodetector and the converging lens can move and / or rotate together to calibrate the optical axes of the laser emitting unit 200 and the receiving unit 400, so that the laser beam emitted by the laser emitting unit 200 is emitted toward the target after being scanned by the scanning unit 300, and is accurately received by the receiving unit 400 after being reflected by the target. The movement of the photodetector and the converging lens together can also be movement in three-dimensional space (forward or backward, left and right, up and down, etc.). The rotation of the photodetector and the converging lens together can also be rotation with the optical axis of the converging lens as the rotation axis.

[0051] Compared with configuring a converging lens for each pixel, in this embodiment, there is only one converging lens on the light receiving path of more than two pixels. In this way, when calibrating the optical axis between the laser emitting unit 200 and the receiving unit 400, the complexity of the operation can be reduced, making the calibration operation simpler and faster.

[0052] In the above embodiment, the optical axis calibration between the laser emitting unit 200 and the receiving unit 400 can be performed by changing the position of the light source and the collimator, and by changing the position of the photodetector and / or the converging lens. The embodiment of the present application is not limited to this. In other embodiments, the optical axis calibration between the laser emitting unit 200 and the receiving unit 400 can be performed only by changing the position of the light source and the collimator. In this case, the two or more pulsed laser beams emitted by the light source only need to be collimated and output through a collimator; and the two or more pixels of the photodetector can be configured with a converging lens together, or they can be configured with their own converging lenses respectively. In some other embodiments, the optical axis calibration between the laser emitting unit 200 and the receiving unit 400 can be performed only by changing the position of the photodetector and / or the converging lens. In this case, the two or more pixels of the photodetector only need to be configured with a converging lens together; and the two or more pulsed laser beams emitted by the light source can be collimated and output through a collimator, or they can be collimated and output through different collimators respectively.

[0053] The following is a detailed description of the laser radar system of the present application using a specific embodiment as an example:

[0054] See also Figure 1 The laser radar system 100 of this embodiment includes: a laser emitting unit 200, a scanning unit 300, a receiving unit 400 and a control unit 500.

[0055] The light source of the laser emitting unit 200 is a narrow pulse laser fiber laser with a wavelength of 1550 nm. Figure 2 FIG. 1 is a schematic diagram of the end face of the optical fiber head of the optical fiber laser in this embodiment, see FIG. Figure 2 The fiber head 201 of the fiber laser has two laser output channels 202a and 202b, and the two laser output channels 202a and 202b are arranged at a specific interval, for example, a fixed interval between 100-300 microns.

[0056] Figure 3 Schematic diagram of a laser transmitter with integrated fiber laser and collimator, see Figure 3 The laser light outputted from two laser output channels 202a and 202b of the optical fiber head of the optical fiber laser is outputted through a collimator to form two laser beams 204a and 204b with a fixed angle.

[0057] The laser emitter 200 integrated with a fiber laser and a collimator is fixed on a laser emitting structure (not shown in the figure), and the rotation angle can be adjusted along the central optical axis of the laser emitter 200 to ensure that the two emitted laser beams 204a and 204b can be detected by the two pixels of the receiving APD photodetector.

[0058] The center distance between the two laser output channels 202 a and 202 b matches the center distance between two pixels of the APD photodetector of the receiving unit 400 .

[0059] The galvanometer of the scanning unit 300 is driven by a motor, and the scanning mode, scanning angle range and scanning frequency of the galvanometer are controlled by the control unit 500; the prism adopts a six-sided prism, and the scanning optical angle of each face is above 90 degrees.

[0060] The photodetector of the receiving unit 400 is an InGaAs-based APD photodetector. Figure 4 Schematic diagram of the APD photodetector in this embodiment. Figure 4 The APD photodetector 401 includes two linearly arranged pixels 402a and 402b. The two pixels 402a and 402b are arranged at a specific center distance. For example, the distance between the two pixels is fixed between 500-1000 microns.

[0061] Figure 5 FIG. 1 is a schematic diagram of a receiving unit receiving a pulsed laser in this embodiment. Figure 5The converging lens (also referred to as the receiving lens) 403 converges the pulsed lasers 404a and 404b of the two laser beams 204a and 204b of the laser emitting unit 200 after being reflected by the target onto the two picture elements 402b and 402a respectively.

[0062] The converging lens 403 is fixed on the receiving structure (not shown in the figure). The position of the converging lens 403 remains unchanged, and the optical axis of the APD photodetector of the receiving unit 400 and the optical axis of the laser emitting unit 200 are calibrated by adjusting the position of the APD photodetector 401 relative to the converging lens 403 in three dimensions.

[0063] When the center line connecting the two pixels 402a and 402b of the APD photodetector forms an angle with the horizontal direction of the machine, the center line connecting the two laser output channels 202a and 202b of the laser emitting unit 200 also forms an angle with the horizontal direction of the machine, and the angle should be the same as the angle between the center line connecting the two pixels 402a and 402b of the APD photodetector and the horizontal direction of the machine.

[0064] The control unit 500 can calculate the distance information and intensity information of the target in real time, and read the angle information of the prism and the galvanometer of the scanning unit 300 in real time.

[0065] The two laser output channels 202a and 202b of the laser emitting unit 200 of the laser radar system 100 correspond one to one with the two picture elements 402a and 402b of the receiving unit 400.

[0066] Figure 6 Schematic diagram of laser emitting by the laser radar system in this embodiment. Figure 6 In the figure, the two laser beams 204a and 204b emitted by the laser emitting unit 200 of the laser radar system 100 are linearly arranged in the vertical direction.

[0067] Figure 7 FIG. 1 is a schematic diagram of the scanning trajectory of the laser radar system in this embodiment. Figure 7 As shown, the two laser beams emitted by the laser emitting unit 200 of the laser radar system 100 are respectively a beam 204a and a beam 204b, and the beam angle α of the two laser beams 204a and 204b is fixed. The light spot 207 of the light beam 204b is scanned in the horizontal direction to form a beam trajectory 208, and the light spot 207 of the light beam 204a is scanned in the horizontal direction to form a beam trajectory 209;

[0068] Figure 7 In the example, the beam angle α is greater than the vertical scanning angle β. Since the beam angle α is greater than the vertical scanning angle β, Figure 7The vertical resolution of the top and bottom of the trajectory diagram formed by the middle scan will be lower than the vertical resolution of the middle part. Among them, the scanning angle β refers to the angle between two adjacent lines scanned by the galvanometer, and is also the angle between two adjacent light rays formed by a laser beam such as 204a scanning.

[0069] In the above-mentioned laser radar system embodiments, the laser radar system 100 can send instructions through the host computer to switch between multiple working modes in real time, thereby realizing dynamic real-time adjustment of the horizontal field of view angle, vertical field of view angle, horizontal resolution, vertical resolution, and refresh frame rate.

[0070] In addition, in the scanning unit 300, since a scanning method combining a prism and a galvanometer is adopted, and both the laser emitting unit 200 and the receiving unit 400 emit and receive pulsed lasers through the scanning unit 300, a high-density point cloud display of the target can be achieved by using fewer light sources and photodetectors.

[0071] Furthermore, the laser emitting unit 200, the receiving unit 400 and the control unit 500 can all be fixedly mounted on a platform or a bracket, and only the prism and the galvanometer can rotate relative to the platform or the bracket, so that the life and reliability of the entire laser radar system 100 are greatly improved.

[0072] The present application also provides a laser radar system calibration method, which can be applied to the laser radar system described in any of the above embodiments. The calibration method may include:

[0073] Rotate the light source together with the collimator to adjust the position where the light beam output by the collimator is incident on the scanning unit; and / or,

[0074] Adjust the positions of two or more pixels relative to the converging lens, or rotate or move two or more pixels together with the converging lens, so that the light beam emitted after scanning by the scanning unit can be accurately received by the receiving unit after being reflected by the target.

[0075] The calibration method of this embodiment can be applied to Figure 1 In the system embodiment shown, the implementation principle and technical effects are similar and will not be repeated here.

[0076] In order to improve the vertical resolution of the laser radar system, in one embodiment, different light beams output by the collimator have a beam angle in the vertical direction, and the beam angle is greater than 0.5 degrees and less than 5 degrees; the calibration method may also include: adjusting the scanning angle of the scanning unit in the vertical direction so that the scanning angle is less than the smallest beam angle among the beam angles. The light beam output by the collimator is provided with a fixed angle, and the angle between different light beams is adjusted in the vertical direction by adjusting the rotation direction of the collimator along the optical axis. After adjustment, the collimator is fixed with the collimator clamp.

[0077] It should be noted that the various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0078] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A laser radar system, It is characterized in that include: A laser emitting unit, a scanning unit, a receiving unit and a control unit, wherein the control unit controls the laser emitting unit to emit laser light, wherein the laser light is emitted after being scanned by the scanning unit so as to be received by the receiving unit after being reflected by a target; wherein the laser emitting unit comprises a light source and a collimator located on a light emission path of the light source, wherein the light source has more than two laser output channels which are linearly arranged in a vertical direction, and laser beams output by different laser output channels are all collimated by the collimator and then output in a divergent manner; wherein the receiving unit comprises a photodetector, wherein the photodetector has more than two picture elements, wherein the number of the picture elements is the same as the number of the laser output channels, wherein the more than two picture elements correspond to the more than two laser output channels one by one, and a converging lens is provided on a light receiving path of the more than two picture elements so that the more than two picture elements receive light reflected back from a target through a converging lens; wherein the scanning unit comprises a multifaceted prism and a galvanometer, wherein the multifaceted prism is used to realize horizontal scanning, and the galvanometer is used to realize vertical scanning.

2. The laser radar system according to claim 1, It is characterized in that The light source is connected to the collimator and can rotate together to calibrate the optical axes of the laser emitting unit and the receiving unit.

3. The laser radar system according to claim 1 or 2, It is characterized in that The photoelectric detector can be moved and / or rotated relative to the converging lens to calibrate the optical axes of the laser emitting unit and the receiving unit.

4. The laser radar system according to claim 1 or 2, It is characterized in that The photodetector and the converging lens can be moved and / or rotated together to calibrate the optical axes of the laser emitting unit and the receiving unit.

5. The laser radar system according to claim 4, It is characterized in that Different light beams output by the collimator have a beam angle in the vertical direction; the scanning angle of the scanning unit in the vertical direction is smaller than the smallest angle among the beam angles.

6. The laser radar system according to claim 5, It is characterized in that The scanning angle of the scanning unit in the vertical direction is adjustable.

7. A calibration method for a laser radar system according to any one of claims 1 to 6, It is characterized in that include: Rotate the light source together with the collimator to adjust the position where the light beam output by the collimator is incident on the scanning unit; and / or, The positions of the two or more picture elements relative to the converging lens are adjusted, or the two or more picture elements are rotated or moved together with the converging lens, so that the light beam emitted after being scanned by the scanning unit is accurately received by the receiving unit after being reflected by the target.

8. The calibration method according to claim 7, It is characterized in that Different light beams output by the collimator have a beam angle in the vertical direction; The calibration method further includes: adjusting a scanning angle of the scanning unit in a vertical direction so that the scanning angle is smaller than a smallest angle among the beam angles.

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