Detection apparatus, lidar, and vehicle

Abstract

Provided in the present disclosure are a detection apparatus, a LiDAR, and a vehicle. The detection apparatus comprises: an emitting end and a receiving end, wherein the emitting end comprises a laser device and an emitting lens assembly; the receiving end comprises a receiving lens assembly and a detector; the laser device and the detector are arranged on a common circuit board; the emitting lens assembly comprises N emitting lenses; the receiving lens assembly comprises N receiving lenses; an ith emitting lens of the emitting lens assembly is the same as an ith receiving lens of the receiving lens assembly, i＝1, …, N, and N is an integer greater than 1; the focal length of the emitting lens assembly is different from the focal length of the receiving lens assembly; and a light-emitting surface of the laser device is located on a focal plane of the emitting lens assembly, and a photosensitive surface of the detector is located on a focal plane of the receiving lens assembly.

Description

Detection devices, lidar and vehicles

[0001] This disclosure claims priority to the Chinese patent application titled “Detection Device, LiDAR and Vehicle” and application number 202410371478.9 filed on March 28, 2024. This disclosure claims priority to the Chinese patent application titled “Detection Device, LiDAR and Vehicle” and application number 202420628141.7 filed on March 28, 2024. The contents of the priority application are incorporated herein by reference in their entirety. Technical Field

[0002] The present disclosure relates to the field of photoelectric detection, and more particularly to a detection device, a laser radar, and a vehicle. Background Art

[0003] LiDAR (LiDAR) is a radar system that uses laser beams to detect the position, velocity, and other characteristic parameters of an object. Due to its high resolution, strong resistance to active interference, compact size, and light weight, LiDAR is widely used in autonomous driving, transportation communications, drones, intelligent robots, and other fields.

[0004] In a LiDAR using a paraxial transceiver optical system, the detection device consists of a transmitter and a receiver. The transmitter includes a laser and a transmitting lens. The receiver includes a detector and a receiving lens. The laser and detector in the detection device typically have different specifications, and the laser's emitting surface and the detector's photosensitive surface may not be in the same plane. The receiving end can have a larger receiving aperture, which can improve the LiDAR's detection capability. The transmitting end can have a smaller transmitting aperture, which can reduce the size of the LiDAR. In some LiDARs, the transmitting and receiving lenses have different lens designs. For example, the number and type of lenses in the transmitting and receiving lenses differ. For example, the operating temperature range of LiDARs is -40°C to 120°C. LiDAR detection performance degrades in high and low temperatures because the focal length, image height, and other lens parameters of the lenses change at these temperatures. Transmitter and receiving lenses with different lens designs may cause the echo spot focused on the detector to exceed the detector's sensitivity range at these temperatures. In some LiDARs, the detector size is configured to be much larger than the echo spot to improve the stability of LiDAR detection performance at these temperatures. Summary of the Invention

[0005] The present disclosure aims to overcome the aforementioned and / or other problems in the prior art by providing a detection device. The device utilizes the same lens for both the transmitting and receiving lenses, enabling flexible adjustment of the focal length based on the position of the laser's light-emitting surface and the detector's light-sensitive surface. This helps ensure the stability of the detection performance of the device and lidar in both high and low temperature conditions.

[0006] According to some aspects of the present disclosure, a detection device is provided. The detection device includes: a transmitting end and a receiving end. The transmitting end includes a laser and a transmitting lens. The receiving end includes a receiving lens and a detector. The laser and the detector are arranged on a common circuit board. The transmitting lens includes N transmitting lenses. The receiving lens includes N receiving lenses. The i-th transmitting lens of the transmitting lens is the same as the i-th receiving lens of the receiving lens, i=1,…,N, and N is an integer greater than 1. The focal length of the transmitting lens is different from the focal length of the receiving lens, the light-emitting surface of the laser is located in the focal plane of the transmitting lens, and the light-sensitive surface of the detector is located in the focal plane of the receiving lens.

[0007] Optionally, the distance between the jth transmitting lens and the j+1th transmitting lens of the transmitting lens is different from the distance between the jth receiving lens and the j+1th receiving lens of the receiving lens, and 1≤j≤N-1.

[0008] Optionally, the transmitting aperture of the transmitting end is smaller than or equal to the receiving aperture of the receiving end.

[0009] Optionally, the back focal length of the receiving lens is smaller than the back focal length of the transmitting lens.

[0010] Optionally, the height of the laser on the common circuit board is smaller than the height of the detector on the common circuit board.

[0011] Optionally, the size of the photosensitive surface of the detector is greater than or equal to the size of the light-emitting surface of the laser.

[0012] Optionally, the receiving field of view of the receiving end is greater than or equal to the transmitting field of view of the transmitting end.

[0013] Optionally, the receiving lens includes a filter, and the filter is located between the Nth receiving lens and the detector. The Nth receiving lens is the receiving lens closest to the detector among the N receiving lenses.

[0014] Optionally, a first distance between the entrance pupil of the transmitting lens and the focal plane of the transmitting lens is greater than a second distance between the entrance pupil of the receiving lens and the focal plane of the receiving lens.

[0015] Optionally, the jth transmitting lens and the j+1th transmitting lens of the transmitting lens are connected by a first lens barrel portion, and the connecting portion has a first length. The jth receiving lens and the j+1th receiving lens of the receiving lens are connected by a second lens barrel portion, and the connecting portion has a second length, 1≤j≤N-1. The first length and the second length satisfy at least one of the following conditions:

[0016] The absolute value of the difference between the first length and the second length does not exceed 30% of the first length, and the absolute value of the difference between the first length and the second length does not exceed 30% of the second length; or the difference between the first length and the second length is less than ±0.5 mm.

[0017] Optionally, the thermal expansion coefficient of the first lens barrel part is between 10 ppm / °C and 50 ppm / °C, and the thermal expansion coefficient of the second lens barrel part is between 10 ppm / °C and 50 ppm / °C.

[0018] Optionally, at least one of the N emitting lenses is a plastic lens.

[0019] Optionally, at least one of the front surface and the back surface of the plastic lens is an even-order aspheric surface configured to correct aberrations.

[0020] Optionally, the plastic lens is rotationally symmetric, and the sag of the plastic lens decreases monotonically in a direction from the rotation center toward the edge of the lens.

[0021] Optionally, the plastic lens is a rotationally symmetric circular lens. Furthermore, at a first temperature, at least one of the front or rear surfaces of the plastic lens has a target sag distribution to reduce aberrations of the plastic lens, wherein the sag at a preset point on at least one of the front or rear surfaces of the plastic lens has a target value. At a second temperature, the sag at at least one of the front or rear surfaces of the plastic lens has a preset value. The second temperature is lower than the first temperature. When the sag at the preset point of the plastic lens increases with increasing temperature, the preset value is lower than the target value; or when the sag at the preset point of the plastic lens decreases with increasing temperature, the preset value is higher than the target value.

[0022] Optionally, the transmitting lens and the receiving lens are configured as wide-angle lenses, the vertical transmitting field of view of the transmitting end is greater than 70 degrees, and the vertical receiving field of view of the receiving end is greater than 70 degrees.

[0023] Optionally, the transmitting lens and the receiving lens have the same distortion curve.

[0024] According to other aspects of the present disclosure, a laser radar is provided, comprising the detection device as described above.

[0025] According to other aspects of the present disclosure, a vehicle is provided, comprising the laser radar as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0027] FIG1 shows a schematic diagram of an exemplary detection device consistent with some embodiments of the present disclosure.

[0028] FIG. 2 illustrates a schematic diagram of an exemplary lens group including a first lens and a second lens, consistent with some embodiments of the present disclosure.

[0029] FIG3 illustrates a schematic diagram of an exemplary detection device consistent with some embodiments of the present disclosure.

[0030] FIG4 illustrates a schematic diagram of an exemplary detection device consistent with some embodiments of the present disclosure.

[0031] FIG. 5A shows the surface shape of an exemplary plastic lens at room temperature consistent with some embodiments of the present disclosure.

[0032] FIG. 5B illustrates the difference in surface shape of an exemplary plastic lens at room temperature and ambient temperature, consistent with some embodiments of the present disclosure.

[0033] FIG. 5C illustrates the surface shape of an exemplary compensated plastic lens relative to an uncompensated plastic lens, consistent with some embodiments of the present disclosure.

[0034] FIG5D illustrates the surface shape of an exemplary compensated plastic lens at ambient temperature and the surface shape of an uncompensated plastic lens at room temperature, consistent with some embodiments of the present disclosure.

[0035] FIG6 shows a schematic diagram of an exemplary lidar consistent with some embodiments of the present disclosure.

[0036] FIG. 7 illustrates a schematic diagram of an exemplary distortion mismatch consistent with some embodiments of the present disclosure.

[0037] FIG8 shows a schematic diagram of exemplary distortion matching consistent with some embodiments of the present disclosure. DETAILED DESCRIPTION

[0038] The following describes the embodiments of the present disclosure. It should be noted that in the specific description of these embodiments, in order to provide a concise description, this specification cannot provide a detailed description of all the features of the actual embodiments. It should be understood that in the actual implementation of any embodiment, just as in the process of any engineering project or design project, in order to achieve the specific goals of the developer and to meet system-related or business-related restrictions, various specific decisions are often made, and this will also change from one embodiment to another. In addition, it is also understandable that although the efforts made in this development process may be complex and lengthy, for ordinary technicians in the field related to the contents disclosed by this disclosure, some changes in design, manufacturing or production based on the technical contents disclosed in this disclosure are just conventional technical means and should not be understood as the contents of this disclosure being insufficient.

[0039] Unless otherwise defined, the technical or scientific terms used in the claims and description should have the usual meaning understood by people with ordinary skills in the technical field to which the present disclosure belongs. The words "first", "second" and similar words used in the patent application description and claims of this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "one" or "a" do not indicate a quantity limitation, but rather indicate the existence of at least one. Words such as "include" or "comprising" mean that the elements or objects appearing before "include" or "comprising" cover the elements or objects listed after "include" or "comprising" and their equivalents, and do not exclude other elements or objects. Words such as "connect", "couple" or "connected" are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0040] In the present disclosure, unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined with each other to form new technical solutions. In the present disclosure, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form new technical solutions.

[0041] In the description of the embodiments of the present disclosure, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0042] The detection device provided according to the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0043] The present disclosure provides a detection device. The detection device includes a transmitter and a receiver. The transmitter includes a laser and a transmitting lens. The receiving end includes a receiving lens and a detector. The laser and detector are mounted on a common circuit board. The transmitting lens includes N transmitting lenses. The receiving lens includes N receiving lenses. The i-th transmitting lens of the transmitting lens is identical to the i-th receiving lens of the receiving lens, where i = 1, ..., N, and N is an integer greater than 1. The focal length of the transmitting lens is different from that of the receiving lens. The light-emitting surface of the laser is located in the focal plane of the transmitting lens, and the light-sensitive surface of the detector is located in the focal plane of the receiving lens. The transmitting and receiving lenses in the detection device of the present disclosure use the same lens. By configuring the same lens, the focal length can be flexibly adjusted, allowing the light-emitting surface of the laser to be located in the focal plane of the transmitting lens, and the light-sensitive surface of the detector to be located in the focal plane of the receiving lens. By using the same lens for both the transmitting and receiving lenses, performance changes of the transmitting and receiving lenses at high and low temperatures can offset each other, ensuring the stability of the detection performance of the detection device and the lidar at high and low temperatures.

[0044] Refer to Figure 1, which shows a schematic diagram of an exemplary detection device 100 consistent with some embodiments of the present disclosure. The detection device 100 may include a transmitter 10 and a receiver 20. The transmitter 10 may include a laser 110 and a transmitting lens 120. The laser 110 may emit a detection beam. The transmitting lens 120 may guide the detection beam into the field of view of the laser radar. The receiving end 20 may include a detector 210 and a receiving lens 220. The receiving lens 220 may guide the echo formed by the detection beam after reflection from an object to the detector 210. As shown in Figure 1, the laser 110 and the detector 210 may be arranged on a common circuit board 130. This can facilitate assembly and debugging and is suitable for mass production. In some embodiments, the laser 110 and the detector 210 may be arranged on two circuit boards. The laser circuit board and the detector circuit board may be placed parallel to each other within the laser radar. Optionally, the laser circuit board and the detector circuit board may be located on the same plane. Alternatively, the laser circuit board and the detector circuit board may be located on different planes.

[0045] In some embodiments of the present disclosure, the laser 110 may be various types of lasers, including but not limited to a vertical cavity surface emitting laser (VCSEL), an edge-emitting laser (EEL), etc. The detector 210 may be various types of detectors, including but not limited to a single photon avalanche diode (SPAD), an avalanche photodiode (APD), a silicon photomultiplier (SiPM), etc.

[0046] In some embodiments, the transmitting lens 120 may include N transmitting lenses 12. The receiving lens 220 may include N receiving lenses 22. N is an integer greater than 1. For example, the N transmitting lenses may be numbered sequentially from 1 to N along the optical axis direction of the transmitting lens 120, such as the first transmitting lens 121, the second transmitting lens 122, ..., the Nth transmitting lens 12 N For example, the N receiving lenses can be numbered from 1 to N in sequence along the optical axis direction of the receiving lens 220, namely, the first receiving lens 221, the second receiving lens 222, ..., the Nth receiving lens 22 N The ith emitting lens 12 of the emitting lens 120 i The i-th receiving lens 22 of the receiving lens 220 i The same, i=1,…,N. For example, N is equal to 2, 3, 4, 5, 6, etc. For example, each transmitting lens of the transmitting lens 120 is respectively the same as each receiving lens of the receiving lens 220. Alternatively, some transmitting lenses in the transmitting lens 120 are the same as some receiving lenses in the receiving lens 220. For example, the first transmitting lens 121 of the transmitting lens 120 can be the same as the first receiving lens 221 of the receiving lens 220. For example, the second transmitting lens 122 of the transmitting lens 120 can be the same as the second receiving lens 222 of the receiving lens 220. …. For example, the N-1th transmitting lens 121 of the transmitting lens 120 can be the same as the first receiving lens 221 of the receiving lens 220. N-1 Can be used with the N-1th receiving lens 22 of the receiving lens 220 N-1 For example, the Nth emitting lens 12 of the emitting lens 120 N Can be used with the Nth receiving lens 22 of the receiving lens 220 NFor example, the transmitting lens 120 includes three transmitting lenses, for example, a first transmitting lens 121, a second transmitting lens 122, and a third transmitting lens 123. The receiving lens 220 includes three receiving lenses, for example, a first receiving lens 221, a second receiving lens 222, and a third receiving lens 223. The i-th transmitting lens 12i of the transmitting lens 120 is identical to the i-th receiving lens 22i of the receiving lens 220, where i = 1, …, N. For example, the first transmitting lens 121 is identical to the first receiving lens 221, the second transmitting lens 122 is identical to the second receiving lens 222, and the third transmitting lens 123 is identical to the third receiving lens 223. For another example, the first transmitting lens 121 is identical to the first receiving lens 221, the second transmitting lens 122 is identical to the second receiving lens 222. For another example, the second transmitting lens 122 is identical to the second receiving lens 222, and the third transmitting lens 123 is identical to the third receiving lens 223. For another example, the first transmitting lens 121 is identical to the first receiving lens 221, and the third transmitting lens 123 is identical to the third receiving lens 223. For another example, the first transmitting lens 121 is identical to the first receiving lens 222. For another example, the second transmitting lens 122 is identical to the second receiving lens 222. For another example, the third transmitting lens 123 is identical to the third receiving lens 223.

[0047] In some embodiments, the transmitting lens 120 may include S transmitting lenses 12. S is an integer greater than 1. The receiving lens 220 may include P receiving lenses 22. P is an integer greater than 1. Optionally, S and P may be equal or unequal. For example, S is greater than P, or S is less than P. For example, S is equal to 2, 3, 4, 5, 6, etc. For example, P is equal to 2, 3, 4, 5, 6, etc. The i-th transmitting lens 12 of the transmitting lens 120 is equal to i The j-th receiving lens 22 of the receiving lens 220 j The same, i=1, ..., S, j=1, ..., P. For example, the first transmitting lens 121 of the transmitting lens 120 can be the same as the second receiving lens 222 of the receiving lens 220. For example, the second transmitting lens 122 of the transmitting lens 120 can be the same as the first receiving lens 221 of the receiving lens 220. For example, the S-1th transmitting lens 121 of the transmitting lens 120 can be the same as the second receiving lens 222 of the receiving lens 220. S-1 Can be used with the Pth receiving lens 22 of the receiving lens 220 PFor example, the transmitting lens 120 includes three transmitting lenses, for example, a first transmitting lens 121, a second transmitting lens 122, and a third transmitting lens 123. The receiving lens 220 includes three receiving lenses, for example, a first receiving lens 221, a second receiving lens 222, and a third receiving lens 223. For example, the first transmitting lens 121 is the same as the third receiving lens 223, the second transmitting lens 122 is the same as the first receiving lens 221, and the third transmitting lens 123 is the same as the second receiving lens 222. For another example, the first transmitting lens 121 is the same as the first receiving lens 221, the second transmitting lens 122 is the same as the third receiving lens 223, and the third transmitting lens 123 is the same as the second receiving lens 222. For another example, the first transmitting lens 121 is the same as the second receiving lens 222, the second transmitting lens 122 is the same as the first receiving lens 221, and the third transmitting lens 123 is the same as the third receiving lens 223. For another example, the first transmitting lens 121 is identical to the third receiving lens 223, the second transmitting lens 122 is identical to the second receiving lens 222, and the third transmitting lens 123 is identical to the first receiving lens 221. For another example, the first transmitting lens 121 is identical to the first receiving lens 221. For another example, the second transmitting lens 122 is identical to the second receiving lens 222. For another example, the third transmitting lens 123 is identical to the third receiving lens 223. For another example, the first transmitting lens 121 is identical to the second receiving lens 222. For another example, the second transmitting lens 122 is identical to the third receiving lens 223. For another example, the third transmitting lens 123 is identical to the first receiving lens 221.

[0048] In some embodiments, the focal length of the transmitting lens 120 may be different from the focal length of the receiving lens 220. 11 Located at the focal plane of the transmitting lens 120, and the photosensitive surface P of the detector 210 21 Located at the focal plane of the receiving lens 220. The light emitting surface P of the laser 110 11 The focal plane of the transmitting lens 120 may include the light emitting surface P of the laser 110. 11 Accurately located at the focal plane of the transmitting lens 120 and the light emitting surface P of the laser 110 11 The distance from the focal plane of the emitting lens 120 is less than a preset value. 11 Slightly deviated from the focal plane of the transmitting lens 120. The photosensitive surface P of the detector 210 21 The focal plane of the receiving lens 220 may include the photosensitive surface P of the detector 210. 21 Accurately located at the focal plane of the receiving lens 220 and the photosensitive surface P of the detector 210 21 The distance from the focal plane of the receiving lens 220 is less than a preset value.21 Slightly deviate from the focal plane of the receiving lens 220. Optionally, the photosensitive surface P of the detector 210 21 The degree of deviation from the focal plane of the receiving lens 220 can be related to the light emitting surface P of the laser 110. 11 The degree of deviation from the focal plane of the transmitting lens 120 may be the same or different.

[0049] In the detection device 100 of the present disclosure, the transmitting lens 120 and the receiving lens 220 use the same lens to achieve different focal lengths. This allows the light-emitting surface of the laser 110 to be located in the focal plane of the transmitting lens 120, and the light-sensitive surface of the detector 210 to be located in the focal plane of the receiving lens 220. Because the transmitting lens 120 and the receiving lens 220 use the same lens, their performance changes at high and low temperatures offset each other, ensuring the stability of the detection performance of the detection device and the lidar at both high and low temperatures, and eliminating the need to design the detector size to be much larger than the echo spot size at room temperature.

[0050] The advantages of using the same lens for both the transmitting and receiving lenses are: (1) it can reduce the number of lens types and ease the difficulty of lens management and production management; (2) it can reduce lens costs, and the more identical lenses used, the lower the cost; (3) it can reduce the impact of lens batch errors on lidar performance, and the errors of identical lenses in the transmitting and receiving lenses (such as curvature radius, thickness, eccentricity, and tilt) can offset each other.

[0051] In addition, at high and low temperatures, the focal length, image height and other parameters of the lens change. The reasons are: the refractive index of the lens changes at high and low temperatures; the thermal expansion and contraction of the lens barrel at high and low temperatures causes the position of the lens to change, and the radius of curvature of the lens to change. The above problems can be solved or alleviated by the present disclosure. Since the transmitting lens and the receiving lens use the same lens (for example, the type and / or number of lenses are the same, such as at least part of the lenses in the transmitting lens and at least part of the lenses in the receiving lens use the same type, and for example, the number of lenses in the transmitting lens is the same as the number of lenses in the receiving lens), the above changes cancel each other out on the transmitting lens and the receiving lens, which can ensure the stability of the detection performance of the detection device and the laser radar at high and low temperatures.

[0052] In some embodiments of the present disclosure, the distance between the jth transmitting lens and the j+1th transmitting lens of the transmitting lens 120 may be different from the distance between the jth receiving lens and the j+1th lens of the receiving lens 220, where 1≤j≤N-1. N may be 2, 3, 4, 5, 6, etc. For example, the transmitting lens 120 includes three transmitting lenses. For example, the distance between the first transmitting lens and the second transmitting lens of the transmitting lens 120 may be different from the distance between the first receiving lens and the second lens of the receiving lens 220, and the distance between the second transmitting lens and the third transmitting lens of the transmitting lens 120 may be different from the distance between the second receiving lens and the third lens of the receiving lens 220. For another example, the distance between the first transmitting lens and the second transmitting lens of the transmitting lens 120 may be different from the distance between the first receiving lens and the second lens of the receiving lens 220. For another example, the distance between the second transmitting lens and the third transmitting lens of the transmitting lens 120 may be different from the distance between the second receiving lens and the third lens of the receiving lens 220. In this way, the focal length (eg, back focal length) of the transmitting lens 120 can be made different from the focal length (eg, back focal length) of the receiving lens 220 while using the same lens.

[0053] The following uses a lens system including a first lens and a second lens as an example to illustrate the focal length and back focal length of a lens system. Referring to FIG2 , a schematic diagram of an exemplary lens system including a first lens L1 and a second lens L2, consistent with some embodiments of the present disclosure, is shown. For example, if the focal length of the first lens L1 is f1, the focal length of the second lens L2 is f2 (the focal length of a convex lens is a positive number, and the focal length of a concave lens is a negative number), and the distance between the optical center of the first lens L1 and the optical center of the second lens L2 is d, the focal length f of the lens system formed by the first lens L1 and the second lens L2 can be defined as:

[0054] The back focal length (BFL) of the lens group formed by the first lens L1 and the second lens L2 can be determined according to formula (1).

[0055] The back focal length BFL of the lens group can be the distance from the last lens (for example, the second lens L2 in the example of FIG. 2 ) to the back focal length F BACK The back focus can be located at the intersection of the back focal plane and the optical axis.

[0056] In some embodiments, for a system including N emission lenses (a first emission lens 121, a second emission lens 122, ..., an Nth emission lens 12 N) of the emitting lens 120, the lens group L of the first emitting lens 121 and the second emitting lens 122 can be determined according to formula (1): 12 Focal length f 12 and back focal length BFL 12 , the lens group L 12 Combined with the third emitting lens 123 to determine the lens group L 123 Focal length f 123 and back focal length BFL 123 And so on, the calculation is combined in sequence until the Nth emitting lens 12 N , the focal length f of the transmitting lens 120 can be determined t and back focal length BFL t .

[0057] In some embodiments, for a system including N receiving lenses (a first receiving lens 221, a second receiving lens 222, ..., an Nth receiving lens 22 N ) receiving lens 220, the lens group L′ of the first receiving lens 221 and the second receiving lens 222 can be determined according to formula (1): 12 The focal length f′ 12 and back focal length BFL′ 12 , the lens group L′ 12 Combined with the third receiving lens 223 to determine the lens group L' 12 The focal length f′ 123 and back focal length BFL′ 123 , and so on, the calculation is combined in sequence until the Nth receiving lens 22 N , the focal length f of the receiving lens 220 can be determined r and back focal length BFL r .

[0058] 3 , which shows a schematic diagram of an exemplary detection device 100 consistent with some embodiments of the present disclosure. As shown in FIG3 , the laser 110 and the detector 210 may be disposed on a common surface of a common circuit board 130 .

[0059] In some embodiments, the height h1 of the laser 110 on the common circuit board 130 may be different from the height h2 of the detector 210 on the common circuit board 130. 11 The photosensitive surface P of the detector 210 21 By adjusting the focal length f of the transmitting lens 120 t and back focal length BFL t , the light emitting surface P11 of the laser 110 can be located at the focal plane of the transmitting lens 120. By adjusting the focal length f of the receiving lens 220 r and back focal length BFLr , the photosensitive surface P of the detector 210 can be 21 Located at the focal plane of the receiving lens 220.

[0060] In some embodiments, the transmitting lens 120 and the receiving lens 220 use the same lens. The distance between the jth transmitting lens and the j+1th transmitting lens of the transmitting lens 120 can be set to be different from the distance between the jth receiving lens and the j+1th lens of the receiving lens 220, so that the back focal length BFL of the receiving lens 220 is r Different from the back focal length BFL of the transmitting lens 120 t . j is a positive integer, and 1≤j<N. For example, the distance between the first transmitting lens 121 and the second transmitting lens 122 of the transmitting lens 120 may be different from the distance between the first receiving lens 221 and the second receiving lens 222 of the receiving lens 220. For example, the distance between the second transmitting lens 122 and the third transmitting lens 123 of the transmitting lens 120 may be different from the distance between the second receiving lens 222 and the third receiving lens 223 of the receiving lens 220. For example, the N-1th transmitting lens 121 of the transmitting lens 120 may be different from the distance between the first receiving lens 221 and the second receiving lens 222 of the receiving lens 220. N-1 With the Nth emission lens 12 N The distance between the receiving lens 220 and the receiving lens 221 may be different from the distance between the receiving lens 220 and the receiving lens 221. N-1 With the Nth receiving lens 22 N When the transmitting lens 120 and the receiving lens 220 each include N lenses with a fixed focal length, each of the transmitting lens 120 and the receiving lens 220 includes (N-1) degrees of freedom for adjusting the focal length, where the degrees of freedom represent the distance between any two adjacent lenses. By flexibly adjusting the distance between adjacent lenses, different focal lengths and back focal plane positions can be achieved for the transmitting lens 120 and the receiving lens 220.

[0061] The height h1 of the laser 110 on the common circuit board 130 and the height h2 of the detector 210 on the common circuit board 130 may be the same or different, and the present disclosure is not intended to be limiting. For example, at least one of the height h1 of the laser 110 on the common circuit board 130 and the height h2 of the detector 210 on the common circuit board 130 may be between 100 μm and 500 μm. In some embodiments, the height h1 of the laser 110 on the common circuit board 130 may be less than the height h2 of the detector 210 on the common circuit board 130. In some embodiments, the back focal length BFL of the receiving lens 220 r It can be smaller than the back focal length BFL of the transmitting lens 120 t .

[0062] The transmitting aperture of the transmitting end 10 may be the same as or different from the receiving aperture of the receiving end 20, and the present disclosure is not intended to limit this. In some embodiments, the transmitting aperture D of the transmitting end 10 t It can be determined by formula (2). t =f t ×tanθ t (2).

[0063] Among them, f t is the focal length of the transmitting lens 120, θ t is the divergence angle of the laser 110 .

[0064] In some embodiments, the receiving aperture D of the receiving end 20 r It can be determined by formula (3). r =f r ×tanθ r (3).

[0065] Among them, f r is the focal length of the receiving lens 220, θ r is the receiving angle of the detector 210.

[0066] In some embodiments of the present disclosure, the transmitting aperture D of the transmitting end 10 is t Can be less than or equal to the receiving aperture D of the receiving end r Larger receiving aperture D r This can help improve the detection capability of the detection device 100 in detecting distant objects. t This can help reduce the size of the detection device 100.

[0067] Launch caliber D t With receiving aperture D r The focal length f of the transmitting lens 120 can be adjusted to t Or the focal length f of the receiving lens 220 r For example, the focal length f of the transmitting lens 120 is t and the focal length f of the receiving lens 220 r The following conditions can be met to make the launch aperture D t Less than or equal to the receiving aperture D r :

[0068] The light-emitting surface size of laser 110 and the photosensitive surface size of detector 210 may be the same or different, and this disclosure is not intended to be limiting. For example, at least one of the light-emitting surface size of laser 110 and the photosensitive surface size of detector 210 may be characterized by a diameter, and both the light-emitting surface diameter and the photosensitive surface diameter may be between 50 μm and 350 μm. In some embodiments, the photosensitive surface size of detector 210 may be larger than the light-emitting surface size of laser 110. For example, the photosensitive surface size of detector 210 may be 20 μm to 50 μm larger than the light-emitting surface size of laser 110.

[0069] The transmitting field of view of the transmitting end 10 and the receiving field of view of the receiving end 20 may be the same or different, and the present disclosure is not intended to limit this. In some embodiments, the focal length f of the receiving lens 220 is r It can be greater than the focal length f of the transmitting lens 120 t , and the photosensitive surface size can be larger than the luminous surface size. According to FOV*f=h, the receiving field of view FOV r Greater than or equal to the emission field of view FOV t . Emission field of view FOV t The divergence angle θ of the laser 110 may be based at least in part on t In some embodiments, the divergence angle θ of the laser 110 is t The receiving angle θ of the detector 210 may be between 15° and 30°. r can be greater than or equal to the divergence angle θ of the laser 110 t .

[0070] In some embodiments of the present disclosure, the receiving lens 220 may include a filter 23. For example, the filter 23 may be located at the Nth receiving lens 220. N and the detector 210. Alternatively, the filter 23 can be integrated on the detector. Alternatively, the filter 23 can be integrated on any receiving lens, for example, by surface treatment or film application on the receiving lens. Alternatively, the filter 23 can be located between the receiving lens and the window. Referring to FIG4 , a schematic diagram of an exemplary detection device consistent with some embodiments of the present disclosure is shown. As shown in FIG4 , the Nth receiving lens 22 N The receiving lens 22 is the receiving lens closest to the detector 210 among the N receiving lenses 22. The filter 23 can filter out undesired light beams. For example, the filter 23 can only transmit the echo formed by the detection light beam emitted by the laser 110 after being reflected by the object.

[0071] In some embodiments of the present disclosure, a first distance Lt between the entrance pupil Pt of the transmitting lens 120 and the focal plane of the transmitting lens 120 is greater than a second distance Lr between the entrance pupil Pr of the receiving lens 220 and the focal plane of the receiving lens 220. The focal plane of the transmitting lens 120 may be located at the light emitting surface P of the laser 110. 11 The first distance Lt can be called the total length of the transmitting lens. The focal plane of the receiving lens 220 can be located at the photosensitive surface P of the detector. 21 The second distance Lr can be referred to as the total length of the receiving lens. In some embodiments, the plane where the entrance pupil position Pt of the transmitting lens 120 is located can overlap with the plane where the entrance pupil position Pr of the receiving lens 220 is located. The first distance Lt can be greater than the second distance Lr.

[0072] In some embodiments, Lt-Lr=h2-h1, where h1 is the device height of the laser 110 and h2 is the device height of the detector 210.

[0073] In some embodiments of the present disclosure, the jth emitting lens 120 of the emitting lens 12 j With the j+1th emission lens 12 j+1 The j-th receiving lens 220 of the receiving lens 220 may be connected by a first lens barrel portion (not shown), and the connecting portion has a first length. j With the j+1th receiving lens 22 j+1 The first and second lengths may be connected by a second barrel portion (not shown), and the connecting portion has a second length. 1≤j≤N-1. In some embodiments, the first length and the second length may satisfy a first condition: the difference between the first length and the second length is less than ±30%. In the present disclosure, "the difference between the first length and the second length is less than ±30%" means that the absolute value of the difference between the first length and the second length does not exceed 30% of the first length or the second length. In some embodiments, the first length and the second length may satisfy a second condition: the difference between the first length and the second length is less than ±0.5 mm.

[0074] It is understandable that the barrel portion connecting two adjacent lenses will expand and contract under high and low temperatures, thereby causing the positions of the two lenses (for example, the distance between the two lenses) to change. The transmitting lens 120 and the receiving lens 220 use the same lens. By configuring the first barrel portion and the second barrel portion to meet at least one of the first condition and the second condition, the lens position change caused by the thermal expansion and contraction of the barrel portion connecting any two adjacent lenses can be consistent in the transmitting lens 120 and the receiving lens 220, which can ensure that the focal length change trends of the transmitting lens 120 and the receiving lens 220 are consistent. In this way, the effect of the focal length change of the transmitting lens 120 on the detection beam and the effect of the focal length change of the receiving lens 220 on the echo can offset each other, which is conducive to keeping the focal length of the transmitting lens and the receiving lens from changing by no more than 5% under high and low temperatures, and can meet the automotive regulations requirements for lidar used for autonomous driving.

[0075] In some embodiments, the thermal expansion coefficient of the first lens barrel portion and the second lens barrel portion can be between 10 ppm / °C and 50 ppm / °C. In some embodiments, the material of the first lens barrel portion and the second lens barrel portion can include metal or plastic. The first lens barrel portion and the second lens barrel portion can be different sections of the same lens barrel, or can belong to different lens barrels.

[0076] In some embodiments of the present disclosure, the transmitting lens 120 may include a glass lens, a plastic lens, or a combination of a glass lens and a plastic lens. In some embodiments, at least one transmitting lens 12 in the transmitting lens 120 and at least one receiving lens 22 in the receiving lens 220 may be a plastic lens. For example, the i-th transmitting lens 12 of the transmitting lens 120 may be a plastic lens. i The i-th receiving lens 22 of the receiving lens 220 i It can be the same plastic lens. At least one of the front surface and the back surface of the plastic lens can be an aspheric surface (for example, an even aspheric surface). In this way, aberrations can be corrected by the design of the aspheric surface. Although the plastic lens is very sensitive to temperature changes, since the transmitting lens 120 and the receiving lens 220 use the same plastic lens, the changes in the plastic lens with temperature can offset each other, which is conducive to keeping the focal length of the transmitting lens and the receiving lens at high and low temperatures. The change does not exceed 5%. In some embodiments, the plastic lens can be rotationally symmetric, and the sagittal height of the plastic lens decreases monotonically in the direction from the rotation center of the plastic lens toward the edge of the plastic lens.

[0077] Since the expansion coefficient of plastic lenses is large and the strength is low, they are more likely to deform at high and low temperatures. i With the i-th receiving lens 22i The front or back surface of a material (e.g., a lens) can change its shape at a specific temperature. A negative surface compensation value can be set in advance. At a specific temperature, the surface shape can be compensated to the ideal shape. For example, a plastic lens can be a rotationally symmetrical circular lens, and the sagitta at any point on the front or back surface can be determined. If the sagitta at a particular point increases at a specific temperature, the sagitta at that point is reduced during processing; conversely, the sagitta at that point is increased.

[0078] In some embodiments, compensation for the surface shape of the plastic lens can be performed as follows. At a first temperature, at least one of the front surface and the rear surface of the plastic lens can have a target sag distribution to reduce the aberration of the plastic lens. The sag of a preset point on at least one of the front surface and the rear surface of the plastic lens can have a target value. At a second temperature, the sag of a preset point on at least one of the front surface and the rear surface of the plastic lens can have a preset value. When the sag of the preset point of the plastic lens increases as the temperature rises, the preset value can be less than the target value. Alternatively, when the sag of the preset point of the plastic lens decreases as the temperature rises, the preset value can be greater than the target value. The first temperature can be the ambient temperature when the detection device 100 is working. The second temperature can be room temperature or processing temperature. As an example, the second temperature can be less than the first temperature, for example, when the detection device 100 is working in a high temperature environment.

[0079] See Figures 5A-5D. Figure 5A shows the surface shape of an exemplary plastic lens at room temperature consistent with some embodiments of the present disclosure, which is configured to correct aberrations. Figure 5B shows the difference in surface shape of an exemplary plastic lens at room temperature and at ambient temperature (e.g., high temperature) consistent with some embodiments of the present disclosure. In Figure 5B, the solid line shows the surface shape of the plastic lens at room temperature, and the dotted line shows the surface shape of the plastic lens at ambient temperature. Figure 5C shows the surface shape of an exemplary compensated plastic lens relative to an uncompensated plastic lens consistent with some embodiments of the present disclosure. In Figure 5C, the solid line shows the surface shape of the uncompensated plastic lens at room temperature, and the dotted line shows the surface shape of the compensated plastic lens at room temperature, and the surface shape compensation amount is set for the surface shape at room temperature. Figure 5D shows the surface shape of an exemplary compensated plastic lens at ambient temperature (e.g., high temperature) consistent with some embodiments of the present disclosure (dotted line) and the surface shape of an uncompensated plastic lens at room temperature (solid line). As shown in FIG5D , the surface shape of the compensated plastic lens at ambient temperature can be compensated to an ideal value, which can be consistent with the surface shape of the uncompensated plastic lens at room temperature, thereby correcting the aberration.

[0080] In an embodiment where the transmitting lens 120 and the receiving lens 220 include plastic lenses, pre-compensating the surface shape of the plastic lens in the above manner can reduce the degradation of detection performance caused by surface shape changes of the detection device and the laser radar under ambient temperature.

[0081] According to another exemplary embodiment of the present disclosure, a laser radar is also provided.

[0082] 6 , which shows a schematic diagram of an exemplary laser radar consistent with some embodiments of the present disclosure. For example, the laser radar 600 may include the detection device 100 described above.

[0083] In some embodiments, the laser 110 of the detection device 100 can provide a detection beam to an object in the field of view through the transmitting lens 120. The detection beam is reflected by the object to form an echo, and the echo is received by the detector 210 through the receiving lens 220.

[0084] In some embodiments, the transmitting end 10 of the detection device 100 may have a transmitting field of view FOV t , the receiving end 20 may have a receiving field of view FOV r . For example, detection within the horizontal field of view of the laser radar 600 can be achieved by rotating the detection device 100. The horizontal field of view can be determined based on the rotation angle of the detection device 100. For example, the detection device 100 can be rotated 360 degrees, and the horizontal field of view of the laser radar is 360 degrees. For another example, detection within the horizontal field of view of the laser radar 600 can be achieved by a scanning mirror (such as a swing mirror, a rotating mirror, a galvanometer mirror, etc.). For another example, detection within the horizontal field of view of the laser radar 600 can be achieved by sequentially activating lasers.

[0085] In some embodiments, the detection device 100 may include multiple lasers and multiple detectors along the vertical direction. The emission field of view of the laser corresponds to the receiving field of view of the detector, and the emission field of view matches its corresponding receiving field of view. The emission fields of the multiple lasers arranged along the vertical direction are combined to form the emission field of view FOV of the transmitting end 10. t The receiving fields of view of the multiple detectors arranged in the vertical direction are combined into the receiving field of view FOV of the receiving end 20. t . Emission field of view FOV t and receiving field of view FOV tThe laser radar 600 may include a horizontal field of view and a vertical field of view, wherein the vertical field of view of the laser radar 600 is at least partially based on the transmitting field of view FOV of the transmitting end 10. t and the receiving field of view FOV of the receiving end 20 r Sure.

[0086] In some embodiments of the present disclosure, the transmitting lens 120 and the receiving lens 220 can be configured as wide-angle lenses. This can expand the vertical transmitting field of view FOV of the transmitting end 10. t and the vertical receiving field of view FOV of the receiving end 20 r , for example, it can be extended to greater than 70°, greater than 80°, greater than 90°, greater than 100°, greater than 120° or greater.

[0087] For the laser radar 600, the emission angle of the detection light beam emitted by the laser 110 through the transmitting lens 120 matches the receiving angle of the echo received by the detector 210 through the receiving lens 220. This ensures that the transmission and reception are aligned, for example, the transmitting field of view of the laser and the receiving field of view of the detector correspond one to one. Referring to Figure 7, Figure 7 shows a schematic diagram of an exemplary distortion mismatch consistent with some embodiments of the present disclosure. When there is no distortion between the transmitting lens 710 and the receiving lens 720, the emission angle α1 is the same as the receiving angle β1, and transmission and reception alignment can be achieved. When there is distortion between the transmitting lens 710 and the receiving lens 720 and the distortion of the transmitting lens 710 and the receiving lens 720 does not match, the actual emission angle α2 is different from the actual receiving angle β2, which will cause a transmission and reception mismatch.

[0088] Referring to Figure 8, Figure 8 shows a schematic diagram of an exemplary distortion matching consistent with some embodiments of the present disclosure. In some embodiments of the present disclosure, the transmitting lens 120 and the receiving lens 220 use the same lens, and the transmitting lens 120 and the receiving lens 220 may include the same or similar distortion curves, so that the actual light output angle α3 is the same as the actual receiving angle β3, which can avoid distortion mismatch between the transmitting lens 120 and the receiving lens 220, resulting in a mismatch between transmission and reception.

[0089] In some embodiments, the laser radar 600 may further include a controller 601. The controller 601 may be connected to the detection device 100 and may control the laser 110 to emit a detection beam and determine at least one of the distance and reflectivity of the object based on the echo received by the detector 120.

[0090] As an example, the controller 601 may include, but is not limited to, a control circuit, a central processing unit (CPU), a field-programmable gate array (FPGA), a digital signal processor (DSP), an application specific integrated circuit (ASIC), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, and the like.

[0091] According to another exemplary embodiment of the present disclosure, a vehicle is further provided. For example, the vehicle may include the laser radar 600 as described above.

[0092] The detection device disclosed in the present invention allows the use of the same lens in the transmitting lens and the receiving lens to achieve differentiated design and flexible adjustment of the focal length.

[0093] The advantages of using the same lens for both the transmitting and receiving lenses are: (1) it can reduce the number of lens types and ease the difficulty of lens management and production management; (2) it can reduce lens costs, because the more identical lenses used, the lower the unit cost; and (3) it can reduce the impact of lens batch errors on lidar performance, because the errors of the same lenses in the transmitting and receiving lenses (such as curvature radius, thickness, eccentricity, and tilt) will cancel each other out.

[0094] In addition, at high and low temperatures, the focal length, image height and other parameters of the lens may change. The reason is that: the refractive index of the lens will change at high and low temperatures; the thermal expansion and contraction of the lens barrel at high and low temperatures will cause the position of the lens to change, and the radius of curvature of the lens will change. The above problems can be solved by the present disclosure. Since the transmitting lens and the receiving lens use the same lens (the type and number of lenses are the same), the above changes can offset each other on the transmitting lens and the receiving lens, thereby ensuring the stability of the detection performance of the detection device and the lidar at high and low temperatures.

[0095] It should be understood that the above description is illustrative and not restrictive. For example, the above embodiments (and / or aspects thereof) can be used in combination with each other. In addition, without departing from the scope of the present disclosure, many modifications can be made to adapt specific conditions or materials to the teachings of the various embodiments of the present disclosure. Although the sizes and types of materials described herein are used to define the parameters of the various embodiments of the present disclosure, the various embodiments are not meant to be restrictive, but rather exemplary embodiments. Upon reading the above description, many other embodiments will be apparent to those skilled in the art. Therefore, the scope of the various embodiments of the present disclosure should be determined with reference to the appended claims, and the full range of equivalents to which these claims are entitled.

Claims

1. A detection device comprising: The transmitting end includes a laser and a transmitting lens; The receiving end includes a receiving lens and a detector; wherein the laser and the detector are arranged on a common circuit board; The transmitting lens includes N transmitting lenses, and the receiving lens includes N receiving lenses. The i-th transmitting lens of the transmitting lens is the same as the i-th receiving lens of the receiving lens, where i=1, ..., N, and N is an integer greater than 1. The focal length of the transmitting lens is different from the focal length of the receiving lens, the light emitting surface of the laser is located at the focal plane of the transmitting lens, and the light sensitive surface of the detector is located at the focal plane of the receiving lens.

2. The detection device according to claim 1, wherein The distance between the jth transmitting lens and the j+1th transmitting lens of the transmitting lens is different from the distance between the jth receiving lens and the j+1th receiving lens of the receiving lens, 1≤j≤N-1.

3. The detection device according to claim 1, wherein: The detection device satisfies at least one of the following: The transmitting aperture of the transmitting end is smaller than or equal to the receiving aperture of the receiving end. The back focal length of the receiving lens is smaller than the back focal length of the transmitting lens. The height of the laser on the common circuit board is smaller than the height of the detector on the common circuit board, or The size of the photosensitive surface of the detector is greater than or equal to the size of the light-emitting surface of the laser.

4. The detection device according to any one of claims 1 to 3, characterized in that: The receiving lens includes a filter, and the filter is located between the Nth receiving lens and the detector. The Nth receiving lens is the receiving lens closest to the detector among the N receiving lenses.

5. The detection device according to claim 4, characterized in that A first distance between an entrance pupil of the transmitting lens and a focal plane of the transmitting lens is greater than a second distance between an entrance pupil of the receiving lens and a focal plane of the receiving lens.

6. The detection device according to any one of claims 1 to 3, characterized in that: The j-th transmitting lens and the j+1-th transmitting lens of the transmitting lens are connected by a first lens barrel portion, and the connecting portion has a first length; the j-th receiving lens and the j+1-th receiving lens of the receiving lens are connected by a second lens barrel portion, and the connecting portion has a second length, 1≤j≤N-1, The first length and the second length satisfy at least one of the following conditions: The absolute value of the difference between the first length and the second length does not exceed 30% of the first length, the absolute value of the difference between the first length and the second length does not exceed 30% of the second length; or The difference between the first length and the second length is less than ±0.5 mm.

7. The detection device according to claim 6, characterized in that The thermal expansion coefficient of the first barrel portion is between 10 ppm / °C and 50 ppm / °C, and the thermal expansion coefficient of the second barrel portion is between 10 ppm / °C and 50 ppm / °C.

8. The detection device according to any one of claims 1 to 3, characterized in that: At least one of the N emitting lenses is a plastic lens.

9. The detection device according to claim 8, characterized in that The plastic lens satisfies at least one of the following: At least one of the front surface and the back surface of the plastic lens is an even-order aspheric surface configured to correct aberrations, or The plastic lens is rotationally symmetric, and a sag of the plastic lens decreases monotonically in a direction from a rotation center toward an edge of the lens.

10. The detection device according to claim 8, characterized in that The plastic lens is a rotationally symmetrical circular lens, and At a first temperature, at least one of the front surface or the back surface of the plastic lens has a target sag distribution to reduce aberrations of the plastic lens, wherein a sag at a predetermined point on at least one of the front surface or the back surface of the plastic lens has a target value, At a second temperature, the sagittal height of the predetermined point on at least one of the front surface or the back surface of the plastic lens has a predetermined value, the second temperature being lower than the first temperature, Wherein, when the sag of the preset point of the plastic lens increases with increasing temperature, the preset value is smaller than the target value; or When the sag height of the preset point of the plastic lens decreases as the temperature rises, the preset value is greater than the target value.

11. The detection device according to any one of claims 1 to 3, characterized in that: The transmitting lens and the receiving lens are configured as wide-angle lenses, the vertical transmitting field of view of the transmitting end is greater than 70 degrees, and the vertical receiving field of view of the receiving end is greater than 70 degrees.

12. The detection device according to claim 11, wherein: The transmitting lens and the receiving lens have the same distortion curve.

13. A laser radar comprising: A detection device as claimed in any one of claims 1 to 12.

14. A vehicle comprising the laser radar according to claim 13.

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