Testing device for laser radar lens

Abstract

The utility model provides a testing device of a laser radar lens. The laser radar lens is a transmitting end lens or a receiving end lens. The test device comprises a light source configured to emit test light to the laser radar lens; the reference plane is fixedly arranged relative to the laser radar lens and is used for calibrating the position of a light-emitting surface or a light-sensing surface corresponding to the laser radar lens; the imaging module is configured to at least move to a first set position and a second set position along the optical axis of the laser radar lens; the first set position is the position when the imaging module images the test light focused by the laser radar lens, and the second set position is the position when the imaging module images the reference plane; the position detection module is configured to obtain coordinates of a first set position and a second set position. Thus, through the testing device provided by the embodiment of the invention, common testing of the defocusing amount and the focal length of the laser radar lens can be effectively realized, and the hardware cost and the process cost are reduced.

Description

Technical Field

[0001] This disclosure relates to the field of lidar technology, and more specifically, to a testing device for lidar lenses. Background Technology

[0002] In recent years, with the rapid development of autonomous driving and intelligent transportation technologies, LiDAR, as an important environmental perception sensor, has faced increasingly higher requirements for performance and accuracy. One of the core components of a LiDAR system is the optical lens, and the accurate measurement of its parameters is crucial to ensuring the performance of the entire system.

[0003] Many lidar systems widely use single-photon avalanche diode (SPAD) detectors. In SPAD-based lidar systems, the coupling efficiency of the optical system is a critical parameter, affecting ranging capability, signal stability, and multi-field calibration accuracy. The defocusing amount of the optical lens has a significant impact on coupling efficiency; a larger defocusing amount leads to a decrease in coupling efficiency, which in turn affects the system's ranging capability and causes changes in the position-energy curve, making it difficult to calibrate performance parameters such as reflectivity at different fields of view. Simultaneously, the focal length is also crucial, significantly affecting the optical lens's field of view and image sharpness.

[0004] To ensure the performance of a LiDAR system, the defocus and focal length of the LiDAR optical lens need to be precisely measured and controlled. Therefore, a measurement system capable of quickly and accurately detecting the defocus and focal length is required for the specific lens of a LiDAR system.

[0005] The content of the background section is merely the technology known to the inventors of this disclosure and does not necessarily represent the prior art in this field. Utility Model Content

[0006] In view of this, the purpose of this disclosure is to provide a testing device for lidar lenses, which can effectively test both the defocusing amount and focal length of lidar lenses, thereby ensuring the quality of lidar optical lenses.

[0007] This disclosure provides a testing device for a lidar lens, wherein the lidar lens is a transmitting lens or a receiving lens; the transmitting lens is used to guide the detection beam emitted by the emitting surface of the lidar to the outside of the lidar, and the receiving lens is used to guide the echo beam generated after the detection beam is reflected on an object to the photosensitive surface inside the lidar.

[0008] The testing apparatus includes:

[0009] A light source is configured to emit test light toward the lidar lens;

[0010] A reference plane is fixedly set relative to the lidar lens and is used to calibrate the position of the light-emitting surface or photosensitive surface corresponding to the lidar lens;

[0011] An imaging module is configured to be movable along the optical axis of the lidar lens to at least a first predetermined position and a second predetermined position; the first predetermined position is the position of the imaging module when imaging the test light focused by the lidar lens, and the second predetermined position is the position of the imaging module when imaging the reference plane;

[0012] The position detection module is configured to obtain the coordinates of the first set position and the second set position.

[0013] Optionally, it also includes a track, on which the imaging module is slidably mounted.

[0014] Optionally, the track includes a first track whose length direction is along the optical axis of the lidar lens, and a second track slidably connected to the first track; wherein the imaging module is slidably mounted to the first track, and the length direction of the second track intersects the length direction of the first track.

[0015] Optionally, the reference plane is the supporting surface of the lidar lens, which is the surface of the lidar lens used to fix the corresponding light-emitting surface or photosensitive surface.

[0016] Optionally, it also includes a calibration plate, which is detachably fixed between the lidar lens and the imaging module. The calibration plate includes a first surface and a second surface that are parallel to each other. The first surface and the second surface are set at a preset interval. The first surface is coplanar with the reference plane, and the second surface is a reflective surface.

[0017] The imaging module can also be moved to a third preset position, which is the position where the imaging module images the second surface.

[0018] The position detection module is also configured to obtain the coordinates of the third set position.

[0019] Optionally, the imaging module includes an autocollimator.

[0020] Optionally, the imaging module includes an imaging unit;

[0021] The testing apparatus also includes a displacement sensor fixed to the imaging unit; the displacement sensor is configured to detect the reference plane.

[0022] Optionally, the displacement sensor is a contact displacement sensor or a non-contact displacement sensor.

[0023] Optionally, the imaging module includes an autocollimator or an imaging unit, and a contact surface fixed relative to the autocollimator or the imaging unit; the autocollimator or the imaging unit is capable of imaging the contact surface, and the contact surface is used to contact the reference plane.

[0024] Optionally, the imaging module further includes a target fixture, which is fixedly connected to the autocollimator or the imaging unit, and the surface of the target fixture facing away from the autocollimator or the imaging unit is the abutment surface.

[0025] The testing apparatus for lidar lenses provided in this disclosure can test lidar lenses. By setting a reference plane fixed relative to the lidar lens, the position of the light-emitting surface or the photosensitive surface of the lidar lens is calibrated, thereby avoiding errors caused by inconsistencies between the position of the light-emitting surface or the photosensitive surface and the actual working position, and improving the reliability of the test. This disclosure can utilize the imaging module to move to a first set position for imaging the test light focused by the lidar lens and a second set position for imaging the reference plane. The position detection module can obtain the coordinates of the first set position and the second set position, thereby effectively testing the defocus amount and focal length of the lidar lens based on the coordinates of the first set position and the second set position. Thus, this disclosure embodiment can simultaneously measure the defocus amount and focal length of the lidar lens using the same testing apparatus. The testing apparatus provided in this disclosure embodiment is not only simple in structure but also more comprehensive, effectively saving testing hardware costs and testing procedures.

[0026] Furthermore, the testing device provided in this embodiment tests the lidar lens externally, which can adapt to lidar lenses of various shapes, thereby meeting diverse testing needs.

[0027] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the accompanying drawings used in the embodiments will be described exemplarily below. These drawings are incorporated in and constitute a part of this specification. They illustrate embodiments conforming to this disclosure and, together with the specification, serve to explain the technical solutions of this disclosure. It should be understood that the following drawings only show some embodiments of this disclosure and should not be considered as limiting the scope. Those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0029] Figure 1Exemplary structures of lidar provided in some embodiments of this disclosure are shown;

[0030] Figure 2a , Figure 2b A schematic diagram of the defocus amount is shown;

[0031] Figure 3 A schematic block diagram of a test apparatus for a lidar lens provided in some embodiments of this disclosure is shown;

[0032] Figure 4a , Figure 4b An optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of this disclosure is shown;

[0033] Figure 5a , Figure 5b An optical schematic diagram of a test apparatus for a lidar lens provided in other embodiments of this disclosure is shown;

[0034] Figure 6 A structural diagram of a test apparatus for a lidar lens provided in some embodiments of this disclosure is shown;

[0035] Figure 7a , Figure 7b An optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of the present disclosure is shown;

[0036] Figure 8a , Figure 8b An optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of the present disclosure is shown;

[0037] Figure 9 A structural diagram of a test apparatus for a lidar lens provided in other embodiments of this disclosure is shown;

[0038] Figure 10 A structural diagram of a test apparatus for a lidar lens provided in some embodiments of the present disclosure is shown. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. The components of the embodiments of this disclosure described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this disclosure provided in the accompanying drawings is not intended to limit the scope of the claimed disclosure, but merely represents selected embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0040] In this document, the term "and / or" merely describes a relationship, indicating that three relationships can exist. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Furthermore, the term "at least one" in this document means any combination of at least two of any one or more elements. For example, including at least one of A, B, and C can mean including any one or more elements selected from the set consisting of A, B, and C.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "coupling," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0043] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0044] To better understand the test objects of this solution, please refer to Figure 1 , Figure 1 Exemplary structures of lidar provided in some embodiments of this disclosure are shown. Lidar 100 includes a transmitting lens 110 and a receiving lens 120. In some embodiments, the lidar may further include a beam splitter 130 and a reflector 140. In some embodiments, the lidar may further include a transmitting unit, a receiving unit, and a scanning mirror (not shown). Here, the lidar lens tested by the testing apparatus provided in the embodiments of this disclosure is either the transmitting lens 110 or the receiving lens 120. Optionally, the transmitting lens and the receiving lens can be disposed in a single structural component. Alternatively, the transmitting lens and the receiving lens can be disposed separately. The transmitting unit may include one or more light emitters. The light emitter can emit a probe beam. The light-emitting surface corresponding to the transmitting lens 110 is the plane on which the transmitting unit emits the probe beam. The receiving unit may include one or more light receivers. The light receiver receives the echo beam of the probe beam reflected by an object and converts the optical signal into an electrical signal. The photosensitive surface corresponding to the receiving lens 120 is the plane on which the receiving unit receives the echo beam.

[0045] In some embodiments, the detection beam emitted from the emitting surface of the emitting unit can be transmitted to the beam splitter 130 via the emitting lens 110. The beam splitter 130 can reflect the detection beam onto the scanning mirror, and then the scanning mirror can reflect the detection beam into the external space of the lidar 100. The echo beam after the detection beam is reflected by the object can be reflected back to the beam splitter 130 via the scanning mirror. The beam splitter 130 can transmit the echo beam and enter the receiving lens 120. After the transmission direction is adjusted by the reflecting mirror 140, the echo beam can be transmitted to the receiving unit via the photosensitive surface. It should be noted that... Figure 1 The arrangement of the lidar lenses shown is merely an example. This disclosure is not intended to limit the structure of the lidar or the arrangement of its lenses. The transmitting and receiving lenses can be... Figure 1 The arrangement shown can also be other arrangements.

[0046] In some embodiments, the lidar may employ a paraxial optical path, for example, the optical paths of the transmitting lens and the receiving lens are separated. The transmitting unit may be positioned close to the transmitting lens. The receiving unit may be positioned close to the receiving lens.

[0047] In optical systems, controlling the defocus and focal length of a lens is extremely important. The defocus of a LiDAR lens can be represented by the difference between the emitter's light-emitting surface and the receiver's photosensitive surface from their theoretically designed positions. Ideally, when parallel light is incident on both the transmitter and receiver lenses, the focus of the transmitter lens converges on the emitter's surface, and the focus of the receiver lens converges on the photosensitive surface. However, in practical applications, assembly issues and other factors can cause the focal position to shift, resulting in defocus. For example, defocus can include two types. For a better understanding of defocus, please refer to [link to relevant documentation / references]. Figure 2a and Figure 2b This is a diagram illustrating the defocus amount. For example... Figure 2a As shown in the diagram, the lens focal point is located on plane a. If the luminescent / photosensitive surface is located on plane a', plane a' is farther from the lens than plane a, which can produce positive defocus; as... Figure 2b As shown, if the light-emitting surface / photosensitive surface is located in plane a", plane a" is closer to the lens than plane a, negative defocus can be generated.

[0048] The testing apparatus for lidar lenses provided in the embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0049] Please see Figure 3 , Figure 3 This is a schematic block diagram of a testing apparatus for a lidar lens provided in some embodiments of this disclosure. The testing apparatus 200 provided in the embodiments of this disclosure includes a light source 210, a reference plane 220, an imaging module 230, and a position detection module 240.

[0050] In some embodiments, the light source 210 can emit test light towards the lidar lens (transmitter lens 110 or receiver lens 120). The test light can be parallel light.

[0051] After the test light is emitted from the lidar lens (transmitter lens 110 or receiver lens 120), it is transmitted to the imaging module 230 via the reference plane 220. Here, the reference plane 220 is fixedly set relative to the lidar lens and is used to calibrate the position of the light-emitting surface or photosensitive surface corresponding to the lidar lens.

[0052] The position of the reference plane 220 is set according to the relative position of the transmitting lens 110 and the transmitting unit in the actual application, or according to the relative position of the receiving lens 120 and the receiving unit in the actual application. For example, the reference plane 220 can be as follows: Figure 3The reference plane 220 is shown as being spaced apart from the lidar lens. In other examples, the reference plane 220 may also be positioned against the lidar lens surface opposite to the light source 210.

[0053] The imaging module 230 can receive test light and perform imaging. For example, the imaging module 230 can be moved along the optical axis of the lidar lens to at least a first set position and a second set position. The first set position is the position of the imaging module 230 when imaging the test light after it has been focused by the lidar lens, and the second set position is the position of the imaging module 230 when imaging the reference plane 220.

[0054] The position detection module 240 can acquire the coordinates of a first set position and a second set position. Based on the coordinates of the first set position and the second set position, the defocus amount and focal length of the lidar lens can be determined.

[0055] Thus, the embodiments of this disclosure can simultaneously measure the defocus and focal length of the transmitting and receiving lenses of the lidar using the same testing device. The testing device provided by the embodiments of this disclosure is not only simple in structure but also more comprehensive, effectively saving hardware and process costs for testing.

[0056] In practical applications, depending on the testing needs, only the transmitting lens 110 can be tested, only the receiving lens 120 can be tested, or both the transmitting lens 110 and the receiving lens 120 can be tested.

[0057] The following section will use the test of the transmitter lens 110 as an example to explain the test process in detail.

[0058] Please see Figure 4a , Figure 4b , Figure 5a , Figure 5b and Figure 6 , Figure 4a , Figure 4b This is an optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of this disclosure. Figure 5a , Figure 5b This is an optical schematic diagram of a test apparatus for a lidar lens provided in other embodiments of this disclosure. Figure 6 This is a structural diagram of a test apparatus for a lidar lens provided in some embodiments of this disclosure.

[0059] The test light emitted by the light source 210 is transmitted to the imaging module 230 via the transmitting end lens 110 and the reference plane 220.

[0060] The imaging module 230 includes an imaging unit 231; the testing device 200 also includes a displacement sensor 250 fixed to the imaging unit 231; the displacement sensor 250 can detect the reference plane 220.

[0061] Imaging unit 231 can be a camera or other imaging device to achieve imaging function. Optionally, imaging unit 231 may also include a lens assembly. The lens assembly may include at least one lens to collimate the transmitted light.

[0062] In this way, the imaging unit 231 and the displacement sensor 250 can quickly and accurately detect the position, which helps to ensure the accuracy of the test.

[0063] Optionally, the displacement sensor 250 can be used with, for example... Figure 4a , Figure 4b The contact displacement sensor 251 shown is the same as or similar to, or may be... Figure 5a , Figure 5b The non-contact displacement sensor 252 shown is the same as or similar to that shown.

[0064] Here, by employing a contact displacement sensor 251, more reliable measurement results can be provided for reference planes 220 with high reflectivity or low contrast. By using a non-contact displacement sensor 252, scratches or damage to the surface of the lidar lens can be avoided. In practical applications, the choice between contact displacement sensor 251 and non-contact displacement sensor 252, based on actual needs, ensures that the testing device is compatible with lidar lenses of different materials and surface properties, improving the comprehensiveness and reliability of the test.

[0065] In some possible embodiments, see Figure 6 The testing device 200 may also include a track 260, on which the imaging module 230 is slidably mounted. This facilitates the movement of the imaging module 230 along the optical axis of the lidar lens.

[0066] In this way, the track 260 provides a precise movement path for the imaging module 230, avoiding positional deviations caused by manual adjustment or unstable movement, and ensuring the repeatability and accuracy of the position of the imaging module 230 in each test. This helps the imaging module 230 to achieve precise positioning between the first set position and the second set position, thereby improving the accuracy of the test.

[0067] Optionally, track 260 may include a first track 261 and a second track 262. Imaging module 230 is slidably mounted to the first track 261. The length direction of the first track 261 is along the optical axis of the lidar lens. The second track 262 can be slidably connected to the first track 261. The length direction of the second track 262 intersects the length direction of the first track 261. In some possible embodiments, the length direction of the second track 262 and the length direction of the first track 261 may be perpendicular to each other.

[0068] In this way, by setting the first track 261 and the second track 262, the imaging module 230 can move freely back and forth along the optical axis of the lidar lens, and can also move in another intersecting direction. This helps the imaging module 230 to align with the optical axis of the lidar lens, so that the imaging module 230 can move along the optical axis of the lidar lens and ensure the accuracy of the test.

[0069] See Figure 4a , Figure 4b and Figure 6 By adjusting the imaging unit 231 to slide on the first track 261 and / or the second track 262 (i.e., moving along the A1 and A2 directions, and / or moving along the B1 and B2 directions), the imaging unit 231 can clearly image the test light, and the current position is recorded as the first set position D1. By adjusting the imaging unit 231 to slide on the first track 261 and / or the second track 262 (i.e., moving along the A1 and A2 directions, and / or moving along the B1 and B2 directions), the contact displacement sensor 251 touches the reference plane 220, and the current position is recorded as the fourth set position D4.

[0070] Combination Figure 3 As can be seen, in this embodiment of the present disclosure, the coordinates of the first set position and the coordinates of the fourth set position can be obtained through the position detection module 240. The position detection module 240 can be located near the track. For example, the position detection module 240 can obtain the coordinates of the first set position and the coordinates of the fourth set position by acquiring images from the imaging module 230 or by acquiring information from the scale of the track 260.

[0071] For example, the coordinates of the first set position D1 can be determined based on the relative positional relationship between the first set position D1 and the zero position of the track 260, and the coordinates of the fourth set position D4 can be determined based on the relative positional relationship between the fourth set position D4 and the zero position of the track 260.

[0072] In practical applications, there is often a positional deviation between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251. To ensure measurement accuracy, the offset between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251 can be obtained. Optionally, the offset between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251 can be measured by other measuring devices (such as an autocollimator).

[0073] In some embodiments, the coordinates of the second set position can be determined based on the coordinates of the fourth set position and the offset between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251.

[0074] In some embodiments, the defocus amount of the lidar lens can be determined based on the coordinates of the first set position, the coordinates of the fourth set position, and the offset between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251. For example, the defocus amount of the lidar lens can be determined using the following formula (1):

[0075] δ=|D1-D4|+H1 (1)

[0076] δ represents the defocus amount of the lidar lens, D1 represents the coordinates of the first set position, D4 represents the coordinates of the fourth set position, and H1 represents the offset between the focal position of the imaging unit 231 and the zero position of the contact displacement sensor 251.

[0077] In some possible embodiments, the test light can form a test pattern; the position detection module 240 can also acquire the image of the test pattern when the imaging module 230 moves to the first set position D1; based on the size of the test pattern, the size of the image of the test pattern and the focal length of the imaging module 230, the focal length of the lidar lens can be obtained.

[0078] Optionally, the test pattern can be two points separated by a first distance. Correspondingly, the image of the test pattern is the image of two points separated by a second distance. Thus, the focal length of the lidar lens can be determined based on the first distance, the second distance, and the focal length of the imaging module 230.

[0079] For example, the focal length of the lidar lens can be obtained by the following formula (2):

[0080]

[0081] f1 represents the focal length of the lidar lens, d1 represents the first distance, d2 represents the second distance, and f2 represents the focal length of the imaging module 230.

[0082] according to Figure 4a , Figure 4b , Figure 5a and Figure 5b As can be seen, in some possible embodiments, the reference plane 220 is the support surface of the lidar lens, which is the surface of the lidar lens used to fix the corresponding light-emitting surface or photosensitive surface.

[0083] By setting the bearing surface as the reference plane, which can be the surface in the lidar lens used to fix the corresponding light-emitting or photosensitive surface, the imaging performance of the lidar lens in actual application can be reflected more accurately, avoiding errors caused by the inconsistency between the reference plane and the actual working position, and improving the accuracy and reliability of the test.

[0084] In some embodiments, such as Figure 6 As shown, the light source 210 can be a collimator. Combined with... Figure 4a , Figure 4b , Figure 5a and Figure 5b The light source 210 may include a collimator-embedded light source 211 and a first lens assembly 212. The collimator-embedded light source 211 can emit test light, which is parallel light. Optionally, the light source 210 may also be in other forms, as long as it can produce parallel light.

[0085] See Figure 5a , Figure 5b and Figure 6 . Figure 5a , Figure 5b The light source 210 in this embodiment may have the same or similar structure as the light source 210 in the foregoing embodiment. Figure 5a , Figure 5b The transmitting lens 110 in the above embodiment may have the same or similar structure as the transmitting lens 110 in the previous embodiment. Figure 5a , Figure 5b The imaging unit 231 in the above embodiment may have the same or similar structure as the imaging unit 231 in the previous embodiment. Figure 5a , Figure 5b The reference plane 220 in the above embodiment may have the same or similar structure as the reference plane 220 in the previous embodiment.

[0086] In some embodiments, the displacement sensor may include a non-contact displacement sensor 252. For example, when recording a first set position D1, if the reference plane 220 is within the detection accuracy range of the non-contact displacement sensor 252, there is no need to adjust the sliding of the imaging unit 231. The non-contact displacement sensor 252 can directly scan the reference plane 220 and record the current position as the fifth set position D5. If the reference plane 220 is not within the detection accuracy range of the non-contact displacement sensor 242, the imaging unit 231 is adjusted to slide on the first track 261 and / or the second track (i.e., move along the A1 and A2 directions, and / or move along the B1 and B2 directions) so that the non-contact displacement sensor 252 can scan the reference plane 220 and record the current position as the fifth set position D5.

[0087] In practical applications, there is often a positional deviation between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252. To ensure measurement accuracy, the offset between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252 can be obtained. Optionally, the offset between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252 can be measured by other measuring devices (such as an autocollimator).

[0088] In some embodiments, the coordinates of the second set position can be determined based on the coordinates of the fifth set position D5 and the offset between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252.

[0089] In some embodiments, the defocusing amount of the lidar lens can be determined based on the coordinates of the first set position, the coordinates of the fifth set position, and the offset between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252. For example, the defocusing amount of the lidar lens can be determined using the following formula (3):

[0090] δ=|D1-D5|+H2 (3)

[0091] δ represents the defocus amount of the lidar lens, D1 represents the coordinates of the first set position, D5 represents the coordinates of the fifth set position, and H2 represents the offset between the focal position of the imaging unit 231 and the zero position of the non-contact displacement sensor 252.

[0092] In some embodiments, refer to Figure 6 The testing device 200 may also include a reflector 270, which can adjust the optical path direction of the test light so that the test light can enter the lidar lens (transmitter lens 110). In some embodiments, the testing device 200 may not include the reflector 270, or may include other components to allow the test light to enter the lidar lens.

[0093] In some other possible embodiments, see Figure 7a and Figure 7b As shown, Figure 7a and Figure 7b This is an optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of the present disclosure. Test light emitted from the light source 210 is transmitted to the imaging module 230 via the transmitting lens 110 and the reference plane 220. Figure 7a , Figure 7b The light source 210 in this embodiment may have the same or similar structure as the light source 210 in the foregoing embodiment. Figure 7a , Figure 7b The transmitting lens 110 in the above embodiment may have the same or similar structure as the transmitting lens 110 in the previous embodiment. Figure 7a , Figure 7b The reference plane 220 in the above embodiment may have the same or similar structure as the reference plane 220 in the previous embodiment.

[0094] In some embodiments, the testing apparatus 200 includes a calibration plate 280. The calibration plate 280 is detachably fixed between the lidar lens (e.g., the transmitter lens 110 or the receiver lens) and the imaging module 230.

[0095] For example, the calibration plate 280 includes a parallel first surface 281 and a second surface 282, which are set at a preset interval. The first surface 281 may be coplanar with the reference plane 220. The second surface 282 may be a reflective surface.

[0096] The imaging module 230 can be moved to a third predetermined position D3. The third predetermined position D3 is the position of the imaging module 230 when imaging the second surface 282. The position detection module 240 can also obtain the coordinates of the third predetermined position D3. The method of obtaining the coordinates of the third predetermined position D3 is similar to the method of obtaining the coordinates of the first and fourth predetermined positions, and will not be described again here.

[0097] It should be noted that the imaging module 230 in this embodiment can also be referred to Figure 6 The slidable assembly on the track allows the imaging module 230 to be moved to the first set position and the third set position.

[0098] In some possible embodiments, the imaging module 230 includes an autocollimator 232.

[0099] Optionally, the autocollimator 232 may include a second lens assembly 2321, a beam splitter 2322, a camera 2323, and an autocollimator built-in light source 2324. The second lens assembly 2321 may include at least one lens.

[0100] For example, when obtaining the first set position, the calibration plate 280 does not need to be installed initially. The test light entering the autocollimator 232 passes through the second lens assembly 2321 and the beam splitter 2322, and is converged onto the camera 2323. Here, when imaging the test light, since the test light emitted by the light source 210 is used, the built-in light source 2324 of the autocollimator is not required. By adjusting the autocollimator 232 to slide on the track, the image of the test light on the autocollimator 232 is made clear, and the current position is recorded as the first set position D1.

[0101] Then, when obtaining the third set position, firstly, the calibration plate 280 is installed between the lidar lens and the autocollimator 232, so that the first surface 281 is coplanar with the reference plane 220. The autocollimator 232 is then adjusted to slide on the track until the second surface 282 is clearly imaged on the autocollimator 232, and the current position is recorded as the third set position D3. Here, since the image is of the second surface 282, the built-in light source 2324 of the autocollimator is required.

[0102] The method for determining the coordinates of the third set position D3 is similar to the method for determining the coordinates of the first set position and the fourth set position, and will not be repeated here.

[0103] In some embodiments, the coordinates of the second set position can be determined based on the coordinates of the third set position D3 and the thickness of the calibration plate 280. The thickness of the calibration plate 280 is the distance between the first surface 281 and the second surface 282.

[0104] Here, when the autocollimator 232 images the test light, the focal point of the image formed by the built-in light source 2324 of the autocollimator coincides with the focal point of the lidar lens. Therefore, the distance between the first set position D1 and the third set position D3, plus the thickness of the calibration plate 280, is the defocus amount of the lidar lens.

[0105] For example, the defocus amount of the lidar lens can be determined based on the coordinates of the first set position, the coordinates of the third set position, and the thickness of the calibration plate 280. For instance, the defocus amount of the lidar lens can be determined using the following formula (4):

[0106] δ=|D1-D3|+H3 (4)

[0107] δ represents the defocusing amount of the lidar lens, D1 represents the coordinates of the first set position, D3 represents the coordinates of the third set position, and H3 represents the thickness of the calibration plate.

[0108] The steps for determining the focal length in this embodiment are similar to those in the previous embodiments. For specific implementation details, please refer to the previous embodiments. Repeated steps will not be repeated here.

[0109] In some possible embodiments, the calibration plate 280 is a flat glass.

[0110] To ensure testing accuracy, the flatness and parallelism of the first surface 281 and the second surface 282 of the calibration plate 280 can meet the preset requirements.

[0111] In some other possible embodiments, see Figure 8a and Figure 8b As shown, Figure 8a and Figure 8b This is an optical schematic diagram of a test apparatus for a lidar lens provided in some embodiments of the present disclosure. Test light emitted from the light source 210 is transmitted to the imaging module 230 via the transmitting lens 110 and the reference plane 220. Figure 8a , Figure 8b The light source 210 in this embodiment may have the same or similar structure as the light source 210 in the foregoing embodiment. Figure 8a , Figure 8b The transmitting lens 110 in the above embodiment may have the same or similar structure as the transmitting lens 110 in the previous embodiment. Figure 8a , Figure 8b The reference plane 220 in the above embodiment may have the same or similar structure as the reference plane 220 in the previous embodiment.

[0112] The imaging module 230 includes an autocollimator 232 or an imaging unit 231, and an abutment surface 291 fixed relative to the autocollimator 232 or the imaging unit 231. The autocollimator 232 or the imaging unit 231 is capable of imaging the abutment surface 291, and the abutment surface 291 is used to abut against the reference plane 220.

[0113] To ensure testing accuracy, the flatness and parallelism of the contact surface 291 can meet the preset requirements.

[0114] In this way, the autocollimator 232 or the imaging unit 231 can image the contact surface 291, and the contact surface 291 is used to contact the reference plane 220. This design ensures that the relative position of the imaging module and the reference plane is accurate, providing a guarantee for subsequent measurements and improving the reliability of the measurement results.

[0115] here, Figure 8a and Figure 8b Taking the imaging module 230 as an autocollimator 232 as an example, the configuration of the imaging module 230 as an imaging unit 231 can be referred to Figure 4a , Figure 4b Corresponding embodiments or Figure 5a , Figure 5b The configuration of the imaging unit 231 in the corresponding embodiment will not be described again here. It should be noted that the test light emitted by the light source 210 is used in this embodiment, so the built-in light source 2324 of the autocollimator is not required.

[0116] In some possible embodiments, the imaging module 230 further includes a target fixture 290, which is fixedly connected to the autocollimator 222 or the imaging unit 221, and the surface of the target fixture 290 facing away from the autocollimator 232 or the imaging unit 231 is an abutment surface 291.

[0117] In this way, by selecting the target tooling 290 and using the surface of the target tooling 290 as the abutment surface 291, an abutment surface 291 that meets the measurement requirements can be quickly formed, which helps to make the measurement convenient and quick.

[0118] It should be noted that the imaging module 230 in this embodiment can also be referred to Figure 6 The slidable assembly on the track allows the imaging module 230 to be moved to the first set position and the second set position.

[0119] For example, the target fixture 290 is first fixedly connected to the autocollimator 232. The test light emitted by the light source 210 enters the transmitting lens 110, and after exiting the transmitting lens 110, it is transmitted to the autocollimator 232 via the target fixture 290. The test light entering the autocollimator 232 passes through the lens assembly 2321 and the beam splitter 2322, and is converged to form an image on the camera 2323. Here, when imaging the contact surface 291, the built-in light source 2224 of the autocollimator can be used.

[0120] By adjusting the autocollimator 232 to slide on the track, the image of the contact surface 291 on the autocollimator 232 is made clear, and the current position is recorded as the first set position D1. By adjusting the autocollimator 232 to slide on the track, the contact surface 291 is brought into contact with the reference plane 220, and the current position is recorded as the second set position D2.

[0121] The method for determining the coordinates of the second set position D2 is similar to the method for determining the coordinates of the first set position and the fourth set position, and will not be repeated here.

[0122] Here, the contact surface 291 is located at the focal point of the autocollimator 232 or the imaging unit 231. Therefore, the distance between the first set position D1 and the second set position D2 is the defocus amount of the lidar lens.

[0123] In some embodiments, the defocusing amount of the lidar lens can be determined based on the coordinates of a first predetermined position and the coordinates of a second predetermined position. For example, it can be determined using the following formula (5):

[0124] δ=|D1-D2| (5)

[0125] δ represents the defocusing amount of the lidar lens, D1 represents the coordinates of the first set position, and D2 represents the coordinates of the second set position.

[0126] The steps for determining the focal length in this embodiment are similar to those in the previous embodiments. For specific implementation details, please refer to the previous embodiments. Repeated steps will not be repeated here.

[0127] As can be seen from the foregoing, the aforementioned embodiment is illustrated using the testing of the transmitting lens 110 as an example. In other embodiments, the position and number of test lenses can be changed. For example, as... Figure 9 As shown, the receiving lens 120 can also be tested, such as... Figure 10 As shown, both the transmitting lens 110 and the receiving lens 120 can be tested.

[0128] The testing process for testing the transmitting lens and the receiving lens in this embodiment is similar, and the structure of the testing device used is similar. For details, please refer to the foregoing embodiments, and repeated parts will not be described again.

[0129] It should be noted that, see Figure 10 Because the arrangement of the lidar lenses illustrated in this embodiment is as follows... Figure 1 As shown, therefore in Figure 10 The system includes two testing devices, one for testing the transmitting lens 110 and the other for testing the receiving lens 120. For example, testing device 200 can test the transmitting lens 110, and testing device 300 can test the receiving lens 120.

[0130] Optionally, to save costs, the reflector 270 in test device 200 and the reflector 370 in test device 300 can share the same reflector, such as... Figure 10 As shown, the reflector used can be either reflector 270 or reflector 370.

[0131] Alternatively, the reflector 270 in the test device 200 and the reflector 370 in the test device 300 can each use their respective corresponding reflectors.

[0132] It should be noted that the embodiments disclosed herein are not intended to limit the execution order of testing the transmitting lens and testing the receiving lens. Testing the transmitting lens can be performed before or after testing the receiving lens, or the testing of the transmitting lens and the receiving lens can be performed simultaneously.

[0133] In practical applications, it is often necessary to control the defocus amount. For example, the performance attenuation needs to be controlled within 10%. Correspondingly, the defocus range of the lidar lens needs to be controlled within ±0.25mm. By selecting various components (such as autocollimators, imaging units, sensors, etc.) that meet the testing accuracy requirements to form a testing device, the above control can be achieved, thereby realizing high-precision measurement.

[0134] In some possible embodiments, the testing device provided in this disclosure can automatically complete the measurement of defocus amount and focal length, such as automatically sliding the imaging module, acquiring images, determining position coordinates, calculating defocus amount and focal length, etc., without manual processing, which helps to improve the automation and integration of the testing device.

[0135] It is understood that the structures illustrated in the embodiments of this disclosure do not constitute a specific limitation on the testing apparatus for lenses in lidar. In other embodiments of this disclosure, the testing apparatus for lenses in lidar may include more or fewer components than illustrated, or combine some components, or split some components, or have different component arrangements.

[0136] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0137] Finally, it should be noted that the above-described embodiments are merely specific implementations of this disclosure, used to illustrate the technical solutions of this disclosure, and not to limit it. The protection scope of this disclosure is not limited thereto. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this disclosure; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure. All should be covered within the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be determined by the protection scope of the claims.

Claims

1. A testing device for a lidar lens, characterized in that, The lidar lens is either a transmitting lens or a receiving lens; the transmitting lens is used to guide the detection beam emitted by the emitting surface of the lidar to the outside of the lidar, and the receiving lens is used to guide the echo beam generated after the detection beam is reflected on the object to the photosensitive surface inside the lidar. The testing apparatus includes: A light source is configured to emit test light toward the lidar lens; A reference plane is fixedly set relative to the lidar lens and is used to calibrate the position of the light-emitting surface or photosensitive surface corresponding to the lidar lens; An imaging module is configured to be movable along the optical axis of the lidar lens to at least a first predetermined position and a second predetermined position; the first predetermined position is the position of the imaging module when imaging the test light focused by the lidar lens, and the second predetermined position is the position of the imaging module when imaging the reference plane; The position detection module is configured to obtain the coordinates of the first set position and the second set position.

2. The testing apparatus according to claim 1, characterized in that, It also includes a track, on which the imaging module is slidably mounted.

3. The testing apparatus according to claim 2, characterized in that, The track includes a first track whose length direction is along the optical axis of the lidar lens, and a second track that is slidably connected to the first track; wherein the imaging module is slidably mounted to the first track, and the length direction of the second track intersects the length direction of the first track.

4. The testing apparatus according to claim 1, characterized in that, The reference plane is the supporting surface of the lidar lens, which is the surface of the lidar lens used to fix the corresponding light-emitting surface or photosensitive surface.

5. The testing apparatus according to any one of claims 1 to 4, characterized in that, It also includes a calibration plate, which is detachably fixed between the lidar lens and the imaging module. The calibration plate includes a first surface and a second surface that are parallel to each other and are set at a preset interval. The first surface is coplanar with the reference plane, and the second surface is a reflective surface. The imaging module can also be moved to a third preset position, which is the position where the imaging module images the second surface. The position detection module is also configured to obtain the coordinates of the third set position.

6. The testing apparatus according to claim 5, characterized in that, The imaging module includes an autocollimator.

7. The testing apparatus according to any one of claims 1 to 4, characterized in that, The imaging module includes an imaging unit; The testing apparatus also includes a displacement sensor fixed to the imaging unit; the displacement sensor is configured to detect the reference plane.

8. The testing apparatus according to claim 7, characterized in that, The displacement sensor can be a contact displacement sensor or a non-contact displacement sensor.

9. The testing apparatus according to any one of claims 1 to 4, characterized in that, The imaging module includes an autocollimator or an imaging unit, and a contact surface fixed relative to the autocollimator or the imaging unit; the autocollimator or the imaging unit is capable of imaging the contact surface, and the contact surface is used to contact the reference plane.

10. The testing apparatus according to claim 9, characterized in that, The imaging module further includes a target fixture, which is fixedly connected to the autocollimator or the imaging unit, and the surface of the target fixture facing away from the autocollimator or the imaging unit is the abutment surface.

Images