Laser radar optical performance comprehensive detection device and method

Abstract

The application provides a kind of laser radar optical performance comprehensive detection device and method, it is related to laser radar detection technical field, it aims at solving the technical problems of single function, insufficient general-purpose and low test efficiency of prior art.Testing function is single, insufficient general-purpose and low test efficiency of prior art.The device comprises: parallel light tube objective, for focusing the laser light source emitted by laser radar system;Splitting mirror, for splitting the optical path of parallel light tube objective into two orthogonal conjugate focal planes;Charge coupled device detector, located at one of the conjugate focal planes, for receiving the laser light source focused by parallel light tube objective;Test laser light source, located at the other conjugate focal plane, for generating laser light source consistent with the wavelength of laser radar system, to simulate the laser echo at infinity;Wherein, the test laser light source is configured to be able to move along the corresponding conjugate focal plane, by adjusting the position of the test laser light source movement, the optical performance of laser radar system can be comprehensively detected.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser radar detection, more particularly, to a laser radar optical performance comprehensive detection device and method. BACKGROUND

[0002] Laser radars are widely used in the fields of spaceflight, automatic driving, surveying and mapping, etc., and therefore, efficient and high-precision comprehensive detection and evaluation of the optical performance of the laser radars is an indispensable link in the current laser radar equipment testing and adjustment.

[0003] In the development and production process of laser radars, the evaluation and testing of the following four optical performance indexes are mainly performed: laser radar optical axis parallelism detection, laser divergence angle testing, laser radar instantaneous receiving field of view, and laser radar scanning field of view angle.

[0004] The existing technology does not have a device and method for simultaneously performing comprehensive evaluation of the above optical indexes, and the existing technology devices and methods close to the present application can only test the laser optical axis parallelism and the laser divergence angle. The existing technology methods for testing the optical axis parallelism include a four-quadrant detector optical axis parallelism testing method, an optical reverse device optical axis parallelism testing method, and a light-emitting diode (LED) assisted light illumination charge coupled device (CCD) imaging parallelism testing method. However, the above methods all have defects such as single testing function, insufficient universality, and insufficient testing efficiency. SUMMARY

[0005] In view of this, the present application provides a laser radar optical performance comprehensive detection device and method, aiming to solve the technical problems of the single testing function, insufficient universality, and low testing efficiency of the existing technology.

[0006] One aspect of the present application provides a laser radar optical performance comprehensive detection device, comprising: a collimator objective lens for focusing a laser light source emitted by a laser radar system; a beam splitter for splitting the optical path of the collimator objective lens into two orthogonal conjugate focal planes; a charge coupled device (CCD) detector arranged at a position corresponding to one of the conjugate focal planes, for receiving the laser light source focused by the collimator objective lens and forming a light spot at a target center position; and a test laser light source arranged at a position corresponding to the other conjugate focal plane, for generating a laser light source consistent with the wavelength of the laser radar system, the laser light source generated by the test laser light source being capable of being focused by the collimator objective lens to the laser radar system, thereby simulating a laser echo at an infinite distance; wherein the test laser light source is configured to be movable along the corresponding conjugate focal plane, and the optical performance of the laser radar system is comprehensively detected by adjusting the position of the test laser light source.

[0007] According to an embodiment of the present application, the laser radar system comprises: a transmitting system for transmitting a laser light source; and a receiving system for receiving a laser echo simulated by the test laser light source.

[0008] According to an embodiment of the present application, the device further comprises: a three-dimensional adjustment platform for adjusting the position of the test laser light source.

[0009] According to an embodiment of the present application, the three-dimensional adjustment platform comprises: a control system, wherein the control system is configured to control the movement of the three-dimensional adjustment platform through control instructions input by an external controller and output the position information of the test laser light source.

[0010] According to an embodiment of the present application, the device further comprises: a host computer in communication connection with the control system, for generating control instructions; wherein the host computer is integrated with a test program, and the test program is configured to control the movement of the three-dimensional adjustment platform, read the spot centroid position and size of the laser radar system, read the coordinates of the test laser light source, and calculate and output the test data results corresponding to the optical axis parallelism, the laser divergence angle, the receiving instantaneous field of view, and the scanning field of view.

[0011] According to an embodiment of the present application, the device further comprises: a 180° reflective element for calibrating the coordinate conversion relationship between the test laser light source and the target surface of the charge coupled device detector.

[0012] According to an embodiment of the present application, the device further comprises: a goniometer for verifying the relationship between the spot position coordinates and the angle of the target surface of the charge coupled device detector.

[0013] According to an embodiment of the present application, the device further comprises: a laser energy attenuation element arranged between the laser radar system and the collimator objective lens, for attenuating the intensity of the laser light source emitted by the laser radar system.

[0014] According to an embodiment of the present application, the collimator objective lens is configured as a reflective collimator objective lens.

[0015] Another aspect of the present application provides a laser radar optical performance comprehensive detection method, comprising: controlling a test laser light source to move along a corresponding conjugate focal plane to search for an optimal position; monitoring the intensity of a received signal of a laser radar system in real time, wherein, when the intensity of the received signal is monitored to be maximum, the position of the test laser light source is recorded; according to the spot centroid position of a charge coupled device detector, the optical axis corresponding to a transmitting system of the laser radar system is calibrated, and according to the position of the test laser light source, the optical axis corresponding to a receiving system of the laser radar system is calibrated; according to the optical axis corresponding to the transmitting system and the optical axis corresponding to the receiving system after calibration, the optical axis parallelism is calculated; according to the spot diameter on the charge coupled device detector, the laser divergence angle of the laser radar system is calculated; according to the limit position of the movement of the test laser light source, the receiving instantaneous field of view of the laser radar system is calculated, wherein the limit position represents the position corresponding to the maximum intensity of the received signal and the position corresponding to the minimum intensity of the received signal; according to the coordinate position of the edge point of the laser scanning angle of the laser radar system, the scanning field of view angle of the laser radar system is calculated; and according to the optical axis parallelism, the laser divergence angle, the receiving instantaneous field of view and the scanning field of view angle, the optical performance comprehensive detection data of the laser radar system is generated.

[0016] Compared with the prior art, the laser radar optical performance comprehensive detection device and method provided by the present application embodiment has at least the following beneficial effects:

[0017] (1) The laser radar optical performance comprehensive detection device and method provided by the present application embodiment uses a parallel light tube objective lens to divide the laser light source emitted by the laser radar system to be tested into two conjugate imaging paths through a beam splitter, and then combines conjugate coordinate conversion calibration and a multi-wavelength laser echo simulation light source to establish an infinite remote laser echo light path simulation, so that the optical axis parallelism, the laser divergence angle, the receiving instantaneous field of view and the scanning field of view angle of the laser radar can be tested with high precision and quantification, thereby solving the technical problems of the prior art, such as single test function, insufficient universality and low test efficiency.

[0018] (2) The laser radar optical performance comprehensive detection device and method provided by the present application embodiment uses a parallel light tube objective lens, a beam splitter and a high-precision three-dimensional adjustment platform to establish the conjugate relationship between the test laser light source and the target surface of the charge coupled device detector, and the laser radar system transceiver optical axis included angle can be calculated through the spot centroid offset, so that the high-precision measurement of μ rad level is realized.

[0019] (3) The laser radar optical performance comprehensive detection device and method provided by the present application embodiment integrates the centroid reading algorithm program, the laser radar received signal intensity discrimination and position path search algorithm program in the upper computer, so that the unnecessary manual intervention process can be simplified, and the high-efficiency automatic detection test mode is realized.

[0020] (4) The laser radar optical performance comprehensive detection device and method provided by the embodiment of the present application is different from the prior art which needs to additionally introduce illumination at the laser radar receiving system end, but uses a test laser light source to combine a laser radar receiving signal strength discrimination and a position path search algorithm to calibrate the optical axis of the laser radar receiving system. This kind of method does not need to additionally design illumination for the laser radar receiving system, does not increase additional illumination structure design or interface design, and is suitable for testing laser radars of various structural layout types such as transceiver combination, separation, unit detection and array detection. BRIEF DESCRIPTION OF DRAWINGS

[0021] The above and other objects, features and advantages of the present application will become more apparent from the following description of embodiments of the present application taken in conjunction with the accompanying drawings, in which:

[0022] Figure 1 A structural diagram of the prior art for measuring parallelism of a laser ranging machine transmitting and receiving system by a four-quadrant detector is schematically shown;

[0023] Figure 2 A structural diagram of the prior art for calibrating optical axis parallelism by an optical reverse device is schematically shown;

[0024] Figure 3 A structural diagram of the prior art for measuring optical axis of a transmitting and receiving system by an auxiliary illumination method is schematically shown;

[0025] Figure 4 A structural diagram of a laser radar optical performance comprehensive detection device according to the embodiment of the present application is schematically shown;

[0026] Figure 5 A coordinate conversion relationship diagram between a test laser light source and a CCD target surface according to the embodiment of the present application is schematically shown. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. It is to be understood, however, that the description is merely exemplary of the present application, and is not intended to limit the scope of the present application. In the following detailed description of the embodiments of the present application, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that one or more embodiments of the present application can be practiced without these specific details. In other instances, well-known structures and functions have not been described in detail in order to avoid obscuring aspects of the present application.

[0028] The terms used herein are merely used to describe specific embodiments, and are not intended to limit the present application. The terms "include", "comprise" and the like used herein indicate the presence of the described features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0029] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0030] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0031] In the embodiments of this invention, the collection, updating, analysis, processing, use, transmission, provision, disclosure, and storage of data (e.g., including but not limited to user personal information) comply with relevant laws and regulations, are used for legitimate purposes, and do not violate public order and good morals. In particular, necessary measures have been taken to prevent unauthorized access to user personal information data and to maintain the security of user personal information and network security.

[0032] LiDAR is widely used in aerospace, autonomous driving, surveying and mapping, and other fields. Therefore, efficient and high-precision comprehensive testing and evaluation of its optical performance is an indispensable part of the testing and assembly of LiDAR equipment. This invention aims to address the evaluation and testing of the following optical performance indicators during the research and development and production of LiDAR:

[0033] (1) LiDAR optical axis parallelism detection

[0034] The parallelism of the optical axes of the lidar transmitting and receiving systems directly determines the lidar's detection capability. Real-time and accurate measurement of the optical axes of the laser transmitting and receiving systems is an important basis for lidar optical assembly and adjustment.

[0035] (2) Laser divergence angle test

[0036] The laser divergence angle of a lidar determines its angular resolution and pointing accuracy performance.

[0037] (3) Instantaneous receiving field of view of lidar

[0038] The instantaneous field of view of a lidar refers to the effective detection field of view that a lidar can receive at a fixed point in an instant. The instantaneous field of view of a lidar affects the performance indicators of the lidar, such as anti-interference and pointing accuracy.

[0039] (4) LiDAR scanning field of view

[0040] The scanning field of view of a lidar refers to the effective detection range of the lidar.

[0041] However, there is currently no device or method for comprehensively evaluating the above-mentioned optical indicators simultaneously. Existing devices and methods similar to this invention can only test the parallelism of the laser optical axis and the laser divergence angle. Existing methods for testing the parallelism of the optical axis include: the optical axis parallelism test method using a four-quadrant detector, the optical axis parallelism test method using an optical inversion device, and the parallelism test method using a light-emitting diode (LED) assisted light from a receiving system to illuminate a charge-coupled device (CCD) for imaging.

[0042] For example, Figure 1 The diagram illustrates a prior art structural diagram of a laser rangefinder transmitter-receiver system for measuring parallelism using a four-quadrant detector.

[0043] like Figure 1 As shown, this device uses a cornerstone prism to achieve a 180° fold in the emitted laser beam, and replaces the ranging receiver detector with a four-quadrant detector to test the angular deviation between the receiving and receiving optical axes. This device requires the laser rangefinder structure to allow for interchangeability between the ranging detector and the four-quadrant detector, increasing the design complexity of the laser rangefinder and limiting the versatility of the testing device. Furthermore, replacing the ranging detector with the four-quadrant detector introduces structural positioning errors, affecting the accuracy of the optical axis test.

[0044] For example, Figure 2 The diagram schematically illustrates the structure of prior art for checking the parallelism of optical axes using an optical reverse device.

[0045] like Figure 2 As shown, this device uses an optical inversion device to partially sample and reflect the laser emitted by the transmitting system, causing a portion of the light to be deflected 180° and enter the receiving optical system. The returned signal is used to determine whether there is a deviation between the optical axes of the transmitting and receiving optical systems. The energy distribution of the laser spot reflected back by this device differs from the energy distribution of the entire emitted laser beam, thus introducing uncontrollable deviations in the optical axis measurement and affecting the accuracy calibration of the optical axis.

[0046] For example, Figure 3 This diagram schematically illustrates the structure of a transceiver system for measuring the optical axis using auxiliary illumination, as described in the prior art.

[0047] like Figure 3As shown, this device uses a parabolic reflector, a beam splitter, and a cornerstone prism to calibrate the position of the white light source within the CCD as a measurement reference. It measures the positional relationship between the emitted laser and the light spot formed by the receiving system after LED illumination on the CCD target surface, calculating the optical axis parallelism between the receiving and transmitting systems. The reflector attenuates the laser intensity entering the CCD. This device can quantitatively measure the angle between the transmitting and receiving systems and the laser divergence angle. However, its reliance on the LED illumination receiving structure limits the layout of the lidar or rangefinder receiving structure. For larger detectors, it is difficult to achieve rear LED illumination, resulting in insufficient test versatility.

[0048] It is evident that existing technologies for testing the optical performance of lidar suffer from drawbacks such as limited testing functionality, insufficient versatility, and inefficient testing. Specifically:

[0049] Regarding the limitation of limited testing functionality:

[0050] Existing optical axis testing devices or methods only detect the optical axis consistency (parallelism) of the transceiver optical system through indirect means (optical axis transition method), and lack the ability to verify the strength of the laser echo signal.

[0051] Existing testing devices or methods can simultaneously test the divergence angle and the parallelism of the light and shadow axes of lidar or rangefinder lasers, but lack means and methods for simultaneously measuring laser emission power.

[0052] Regarding the lack of versatility:

[0053] Existing technologies for detecting the laser receiving and transmitting axes of lidar employ methods such as replacing the detection element (four-quadrant detector) or adding an auxiliary illumination source. These methods impose specific structural requirements on the laser receiving system to meet the testing requirements of the laser testing system. However, this increases the design complexity of the lidar and reduces the versatility of the testing system.

[0054] Existing methods for detecting the optical axis of a lidar receiver employ an optical inversion device to partially sample and reflect the emitted laser. While introducing an optical inversion device during assembly and adjustment can solve the problem of test versatility, the centroid of the light spot formed by the partial sampled emitted laser after reflection by the inversion device or component does not coincide with the centroid of the full-aperture laser emission spot. This optical axis calibration method has significant uncertainty and introduces large errors.

[0055] Regarding the drawback of low testing efficiency:

[0056] Most existing technologies rely on human eyes to observe the optical axis deviation at the CCD target surface, which has the disadvantages of inconsistent interpretation and low testing efficiency.

[0057] Existing technologies rely on manual adjustment of the optical path. For example, manually adjusting the CCD position using a translation stage can easily introduce human error.

[0058] Based on this, embodiments of the present invention provide a comprehensive testing device for the optical performance of lidar, which aims to solve the technical problems of existing technologies having limited testing functions, insufficient versatility, and low testing efficiency.

[0059] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0060] Figure 4 The diagram illustrates the structure of a comprehensive testing device for the optical performance of a lidar according to an embodiment of the present invention.

[0061] like Figure 4 As shown, the structure of the comprehensive testing device for the optical performance of lidar in this embodiment may include, for example, the lidar system under test, a collimator objective lens, a beam splitter, a charge-coupled device detector (CCD detector), and a test laser source.

[0062] Among them, the collimator objective lens is used to focus the laser source emitted by the lidar system to form a collimated beam (parallel beam).

[0063] A beam splitter is used to divide the optical path of a collimator objective into two orthogonal conjugate focal planes. One path is used to test the output light from the laser source, and the other path is used for imaging by the CCD detector. The two paths are conjugate through the collimator objective and the beam splitter.

[0064] The CCD detector is positioned at a location corresponding to one of the conjugate focal planes to receive the laser light source focused by the collimator objective lens and form a light spot at the target center.

[0065] The test laser source is located at a position corresponding to another conjugate focal plane to generate a laser source with the same wavelength as the lidar system. The laser source generated by this test laser source can be focused onto the lidar system by the collimator objective lens to simulate the laser echo at infinity.

[0066] The test laser source is configured to move along the corresponding conjugate focal plane. By adjusting the position of the test laser source, the optical performance of the lidar system is comprehensively tested.

[0067] In this embodiment, the test laser source and CCD detector are located on two optical conjugate surfaces of the collimator objective lens, respectively. The spatial correspondence for angle and position calibration is established by beam splitting imaging via a beam splitter, thereby achieving high-precision imaging and centroid measurement.

[0068] The comprehensive testing device for the optical performance of lidar provided in this invention uses a collimator objective to split the laser source emitted by the lidar system under test into two conjugate imaging paths through a beam splitter. Combined with conjugate coordinate transformation calibration and multi-wavelength laser echo simulation light source, an infinite laser echo optical path simulation is established. This allows for high-precision quantitative testing of the lidar's optical axis parallelism, laser divergence angle, instantaneous receiving field of view, and scanning field of view. Therefore, it solves the technical problems of existing technologies, such as limited testing functions, insufficient versatility, and low testing efficiency.

[0069] According to an embodiment of the present invention, a lidar system may specifically include a transmitting system and a receiving system.

[0070] The transmitting system is used to emit laser light sources.

[0071] The receiving system is used to receive laser echoes generated by the simulated test laser source.

[0072] According to an embodiment of the present invention, the comprehensive testing device for the optical performance of lidar may further include, for example, a high-precision three-dimensional adjustment platform.

[0073] This high-precision three-dimensional adjustment platform is used to adjust the position of the test laser source, achieving optical path alignment, traversing the focal plane of the test laser source, and accurately locating the intersection of the optical axes. The high-precision three-dimensional adjustment platform features high displacement accuracy and strong motion stability.

[0074] According to an embodiment of the present invention, the high-precision three-dimensional adjustment platform is configured with a control system, wherein the control system is configured to control the movement of the three-dimensional adjustment platform through control commands input from an external controller (such as a host computer), and output the position information of the test laser source.

[0075] The comprehensive testing device for the optical performance of lidar provided in this invention utilizes a collimator objective, a beam splitter, and a high-precision three-dimensional adjustment platform to establish a conjugate relationship between the test laser source and the CCD detector target surface. The angle between the light and light axes of the lidar system can be calculated by the centroid offset of the light spot, achieving high-precision measurement at the μrad level.

[0076] According to an embodiment of the present invention, the comprehensive testing device for the optical performance of lidar may further include, for example, a host computer.

[0077] The host computer communicates with the control system and is used to generate control commands.

[0078] The host computer integrates a test program, which is configured to control the movement of the three-dimensional adjustment platform, read the position and size of the laser radar system's spot centroid, read the coordinates of the test laser source, and calculate and output the optical axis parallelism, laser divergence angle, receive the instantaneous field of view, and the test data results corresponding to the scanning field of view.

[0079] In this embodiment, the host computer can specifically integrate a centroid reading algorithm program, a lidar received signal strength discrimination and position path search algorithm program, which can simplify unnecessary manual intervention processes and realize a highly efficient automated detection and testing method.

[0080] According to an embodiment of the present invention, the comprehensive optical performance testing device for lidar may further include, for example, a 180° reflective element.

[0081] The 180° reflective element is used to calibrate the coordinate transformation relationship between the test laser source and the target surface of the CCD detector.

[0082] According to an embodiment of the present invention, the comprehensive testing device for the optical performance of lidar may further include, for example, a goniometer.

[0083] The goniometer is used to verify the relationship between the position coordinates of the target spot on the CCD detector and the angle.

[0084] According to an embodiment of the present invention, the comprehensive optical performance testing device for lidar may further include, for example, a laser energy attenuation element.

[0085] The laser energy attenuation element is located between the lidar system and the collimator objective lens to attenuate the intensity of the laser source emitted by the lidar system.

[0086] According to an embodiment of the present invention, the collimator objective is configured as a reflective collimator objective.

[0087] The working principle of this comprehensive testing device for the optical performance of lidar is as follows:

[0088] The test laser source and the CCD target surface are positioned on two conjugate focal planes formed by a beam splitter and placed on the collimator objective lens. A high-precision 180° reflector is then used to calibrate the coordinate transformation relationship between the test laser source and the CCD target surface. The test laser source is then moved across the focal planes, and the positions of the traversed points are recorded to establish the correspondence between the focal plane coordinates of the test laser source and the CCD pixel points. Figure 5 As shown.

[0089] Figure 5 The diagram illustrates the coordinate transformation relationship between the test laser source and the CCD target surface according to an embodiment of the present invention.

[0090] likeFigure 5 As shown, coordinate relationship calibration allows for real-time capture of the test laser source position at the CCD target surface. After establishing the coordinate transformation relationship, a precision goniometer is used to verify the relationship between the position coordinates and angles of the light spot at the CCD target surface (to verify the collimator distortion error).

[0091] In this embodiment, by utilizing the correspondence between the focal plane image height and angle of the calibrated collimator objective lens, the parallelism of the lidar optical axis, the laser divergence angle, the instantaneous field of view of reception, and the scanning field of view can be quantitatively tested with high precision.

[0092] The comprehensive testing device for the optical performance of lidar provided in this invention differs from the prior art, which requires additional illumination at the lidar receiving system. Instead, it uses a test laser source combined with lidar received signal strength discrimination and position path search algorithms to calibrate the optical axis of the lidar receiving system. This method does not require additional illumination design for the lidar receiving system, nor does it add any additional illumination structure design or interface design. It is suitable for testing lidar with various structural layout types, such as combined transmit and receive, separate transmit and receive, unit detection, and array detection.

[0093] This invention also provides a comprehensive testing method for the optical performance of lidar, implemented based on the lidar optical performance comprehensive testing device described above. This method may include, for example:

[0094] S1 controls the test laser source to move along the corresponding conjugate focal plane to search for the optimal position.

[0095] In this embodiment, the laser emitted by the lidar emitting system is attenuated by the laser energy attenuation element and then imaged onto the CCD target surface by the collimator objective lens. The host computer records the centroid position of the emitted laser spot of the lidar system.

[0096] The laser emitted from the test laser source passes through the collimator objective lens and is then incident into the lidar receiving system. The host computer controls the test laser source to move along the focal plane to search and monitors the intensity of the signal received by the lidar system in real time.

[0097] S2, monitors the intensity of the signal received by the lidar system in real time, and records the position of the test laser source when the intensity of the received signal is the maximum.

[0098] In this embodiment, the position of the test light source is recorded when the host computer detects the position with the maximum signal strength.

[0099] S3. Based on the position of the centroid of the CCD detector's spot, calibrate the optical axis corresponding to the transmitting system of the lidar system, and based on the position of the test laser source, calibrate the optical axis corresponding to the receiving system of the lidar system.

[0100] In this embodiment, the centroid position of the CCD spot is utilized. To calibrate the optical axis of the lidar transmitting system, the position of the test laser source is used. Calibrate the optical axis of the lidar receiving system.

[0101] S4. Based on the optical axis corresponding to the calibrated transmitting system and the optical axis corresponding to the receiving system, the optical axis parallelism is calculated.

[0102] In this embodiment, the angle between the optical axes is calculated based on the optical axis corresponding to the calibrated transmitting system and the optical axis corresponding to the receiving system.

[0103] For example, the angle θ between optical axes can be calculated as follows:

[0104] (1)

[0105] Where θ represents the angle between the optical axes, and f represents the focal length of the collimator objective.

[0106] S5. The laser divergence angle of the lidar system is calculated based on the spot diameter on the CCD detector.

[0107] In this embodiment, the diameter of the Gaussian-distributed spot 1 / e² on the CCD is... This can reflect the divergence angle of the emitted laser from the lidar system.

[0108] For example, the divergence angle of the emitted laser can be calculated in the following way. :

[0109] (2)

[0110] S6. Based on the extreme positions of the test laser source movement, the instantaneous field of view of the lidar system is calculated. The extreme positions represent the positions corresponding to the maximum intensity of the received signal and the minimum intensity of the received signal.

[0111] In this embodiment, the host computer controls the test laser source to move along the focal plane to search for and monitor the intensity of the signal received by the lidar. When it moves to the extreme positions where the lidar system can receive the test laser signal, the laser source will move to the extreme positions at both ends. At that time, the instantaneous field of view received by the lidar can be calculated.

[0112] For example, the instantaneous field of view of the receiver can be calculated in the following way. :

[0113] (3)

[0114] S7. The scanning field of view of the lidar system is calculated based on the coordinates of the edge points of the laser scanning angle emitted by the lidar system.

[0115] In this embodiment, the coordinate positions of the edge points of the scanning angle of the emitted beam of the lidar system are recorded. This allows the calculation of the laser radar scanning field of view.

[0116] For example, the scanning field of view can be calculated in the following way. :

[0117] (4)

[0118] S8 generates comprehensive optical performance test data for the lidar system based on optical axis parallelism, laser divergence angle, instantaneous receiving field of view, and scanning field of view.

[0119] Through the above operations, high-precision quantitative testing of lidar optical axis parallelism, laser divergence angle, instantaneous field of view of reception, and scanning field of view can be completed, obtaining comprehensive optical performance test data, effectively solving the technical problems of existing technologies having single testing functions, insufficient versatility, and low testing efficiency.

[0120] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A device for comprehensive detection of optical performance of a laser radar, characterized in that, The device comprises: a parallel light tube objective lens for focusing a laser light source emitted by a laser radar system; a beam splitter for splitting the optical path of the parallel light tube objective lens into two orthogonal conjugate focal planes; a charge coupled device detector arranged at a position corresponding to one of the conjugate focal planes, for receiving the laser light source focused by the parallel light tube objective lens and forming a light spot at a target center position thereof; a test laser light source arranged at a position corresponding to the other conjugate focal plane, for generating a laser light source consistent with the wavelength of the laser radar system, the laser light source generated by the test laser light source being capable of being focused by the parallel light tube objective lens to the laser radar system, thereby simulating a laser echo at an infinite distance; a three-dimensional adjustment platform for adjusting the position of the test laser light source, comprising a control system, wherein the control system is configured to control the movement of the three-dimensional adjustment platform through control instructions input by an external controller and output position information of the test laser light source; a host computer in communication connection with the control system, for generating control instructions, wherein the host computer integrates a test program configured to control the movement of the three-dimensional adjustment platform, read the light spot centroid position and size of the laser radar system, and read the coordinates of the test laser light source, and calculate and output test data results corresponding to optical axis parallelism, laser divergence angle, receiving instantaneous field of view, and scanning field of view; a 180° reflecting element for calibrating the coordinate conversion relationship between the test laser light source and the target surface of the charge coupled device detector; wherein the test laser light source is configured to move along the corresponding conjugate focal plane, and the optical performance of the laser radar system is comprehensively detected by adjusting the position of the test laser light source; wherein after the positions of the charge coupled device detector and the test laser light source are set, the coordinate conversion relationship between the test laser light source and the target surface of the charge coupled device detector is calibrated using the 180° reflecting element, and the test laser light source is translated across the focal plane, the traversal point positions are recorded, the corresponding relationship between the focal plane coordinate points of the test laser light source and the pixel points of the charge coupled device detector is established, and the corresponding relationship is used to perform high-precision quantitative testing on the laser radar optical axis parallelism, laser divergence angle, receiving instantaneous field of view, and scanning field of view angle.

2. The apparatus of claim 1, wherein, The laser radar system comprises: a transmitting system for transmitting a laser light source; a receiving system for receiving the laser echo simulated by the test laser light source.

3. The apparatus of claim 1, wherein, The device further comprises: a goniometer for verifying the relationship between the target surface light spot position coordinates and the angle of the charge coupled device detector.

4. The apparatus of claim 1, wherein, The device further comprises: a laser energy attenuation element arranged between the laser radar system and the parallel light tube objective lens, for attenuating the intensity of the laser light source emitted by the laser radar system.

5. The apparatus of claim 1, wherein, The parallel light tube objective lens is configured as a reflective parallel light tube objective lens.

6. A method for comprehensive detection of optical performance of a laser radar, applied to the comprehensive detection device of optical performance of a laser radar according to any one of claims 1-5, characterized in that, The method comprises: The test laser light source is controlled to move along a corresponding conjugate focal plane to search for an optimal position, wherein the outgoing laser of the laser radar emission system is attenuated by a laser energy attenuation element, then imaged by the parallel light tube objective to the target surface of the charge coupled device detector, and the laser spot centroid position of the laser radar system is recorded by the upper computer. The outgoing laser of the test laser light source is incident to the laser radar receiving system after passing through the parallel light tube objective, and the upper computer controls the test laser light source to move along the focal plane to search for an optimal position; The intensity of the received signal of the laser radar system is monitored in real time, wherein when the intensity of the received signal is monitored to be maximum, the position of the test laser light source is recorded; According to the laser spot centroid position of the charge coupled device detector, the optical axis corresponding to the emission system of the laser radar system is calibrated, and according to the position of the test laser light source, the optical axis corresponding to the receiving system of the laser radar system is calibrated; According to the calibrated optical axis corresponding to the emission system and the optical axis corresponding to the receiving system, the optical axis parallelism is calculated; According to the laser spot diameter on the charge coupled device detector, the laser divergence angle of the laser radar system is calculated; According to the limit position of the movement of the test laser light source, the receiving instantaneous field of view of the laser radar system is calculated, wherein the limit position represents the position corresponding to the maximum intensity of the received signal and the position corresponding to the minimum intensity of the received signal of the laser radar system; According to the coordinate position of the edge point of the laser scanning angle of the laser radar system, the scanning field of view angle of the laser radar system is calculated; According to the optical axis parallelism, the laser divergence angle, the receiving instantaneous field of view and the scanning field of view angle, the comprehensive detection data of the optical performance of the laser radar system is generated.

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