Laser receiving unit, laser receiving module, laser radar and intelligent equipment

Abstract

The embodiment of the invention discloses a laser receiving unit. The laser receiving unit comprises a laser receiver and a light ray adjusting part, the light ray adjusting part comprises an optical conduction part and an optical attenuation part, and the optical conduction part performs total internal reflection processing on echo signals and then transmits the echo signals subjected to total internal reflection processing to a laser receiving surface of the laser receiver. And the optical attenuation part performs intensity attenuation processing on the echo signal, and transmits the echo signal subjected to the intensity attenuation processing to a laser receiving surface of the laser receiver. According to the invention, the optical conduction part is arranged, and the performance of the optical conduction part is utilized to reflect the echo signal reflected by an object at a short distance back to the laser receiving surface of the laser receiver in a total internal reflection mode, so that the signal receiving range of the laser receiver can be effectively expanded. According to the invention, attenuation processing is carried out on the echo signal reflected by the object in the middle and close distance, the intensity of the echo signal incident to the laser receiving surface is reduced, and saturation of the laser receiver is avoided.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of laser radar technology, and specifically to a laser receiving unit, a laser receiving module, a laser radar and an intelligent device. Background Art

[0002] Lidar (Light Detection and Ranging) is used to detect targets, where the Lidar includes a laser transmitter and a laser receiver. Usually, the optical axis of the laser transmitter provided by the related technology is separated from the optical axis of the laser receiver by a certain distance, resulting in the laser receiver being less likely to receive the echo signal reflected by the target at a close distance when the target is closer to the Lidar, i.e., the signal receiving range of the laser receiver is narrow, which easily leads to the Lidar being unable to effectively detect the target at a close distance. Summary of the invention

[0003] In order to solve the above technical problems, the embodiments of the present application provide a laser receiving unit, a laser receiving module, a laser radar and an intelligent device to improve the technical problem that the signal receiving range of the laser receiver provided by the related technology is narrow.

[0004] In a first aspect, an embodiment of the present application provides a laser receiving unit, comprising a laser receiver and a light adjustment component, wherein the light adjustment component comprises an optical transmission part and an optical attenuation part; the optical transmission part is arranged around the laser receiver, and the optical transmission part is configured to perform total internal reflection processing on the echo signal from a first position range, and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver; the optical attenuation part is arranged on the laser receiving surface of the laser receiver, and the optical attenuation part is configured to perform intensity attenuation processing on the echo signal from a second position range, and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver.

[0005] Optionally, the orthographic projection of the optical transmission portion on the laser receiving surface is located on a side of the light adjusting component away from the laser emitter.

[0006] Optionally, the optical transmission part includes a first upper surface and a first lower surface arranged opposite to each other, the first upper surface is configured to receive an echo signal, wherein the first upper surface is provided with a first optical film, the first lower surface is provided with a second optical film, the reflectivity of the first optical film is less than a first preset threshold, the reflectivity of the second optical film is greater than a second preset threshold, and the second preset threshold is greater than the first preset threshold.

[0007] Optionally, the orthographic projection of the optical attenuation portion on the laser receiving surface at least partially overlaps with the area where the laser receiver is located; or, The orthographic projection of the optical attenuation portion on the laser receiving surface covers the area where the laser receiver is located.

[0008] Optionally, the optical attenuation portion includes a second upper surface and a second lower surface arranged opposite to each other, the second upper surface is configured to receive an echo signal, wherein the second upper surface is provided with a third optical film, the second lower surface is provided with a fourth optical film, the reflectivity of the third optical film is greater than a third preset threshold but less than a fourth preset threshold, the reflectivity of the fourth optical film is less than a fifth preset threshold, and the fifth preset threshold is less than the third preset threshold.

[0009] Optionally, the light adjusting member is a curved prism, and the curved prism includes the optical transmission part and the optical attenuation part. The optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver.

[0010] Optionally, an incident angle of an echo signal from any incident position of the optical transmission portion in the optical transmission portion is greater than a critical angle.

[0011] Optionally, the light adjusting member is an array waveguide structure, the array waveguide structure includes the optical transmission part and the optical attenuation part, the optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver.

[0012] Optionally, at least one first reflection surface is provided in the optical transmission part, and the at least one first reflection surface is tiltedly arranged in sequence in the optical transmission part along the light propagation direction of the echo signal in the optical transmission part, and the reflectivity of the first reflection surface is greater than a sixth preset threshold value; A plurality of second reflection surfaces are provided in the optical attenuation portion. Along the light propagation direction of the echo signal in the optical attenuation portion, the plurality of second reflection surfaces are arranged in sequence and tilted behind the first reflection surface, and the reflectivity of the second reflection surface is less than or equal to the reflectivity of the first reflection surface.

[0013] Optionally, the arrayed waveguide structure comprises an upper waveguide surface and a lower waveguide surface arranged opposite to each other, the upper waveguide surface is configured to receive an echo signal, and along the propagation direction of the light, the first reflection surface is arranged at an acute angle with the upper waveguide surface, and / or the second reflection surface is arranged at an acute angle with the upper waveguide surface, and the acute angle is [ , ] any value between ].

[0014] Optionally, in the arrayed waveguide structure, the mirror distances between two adjacent second reflection surfaces are equal, and the projection length of the second reflection surface on the upper surface of the waveguide is equal to the mirror distance; or, in the arrayed waveguide structure, the mirror distances between two adjacent second reflection surfaces are equal, and the projection length of the second reflection surface on the upper surface of the waveguide is equal to the target distance, and the target distance is the sum of the mirror distance and a preset margin length.

[0015] Optionally, along the propagation direction of the light, the reflectivity of the last second reflective surface among the plurality of second reflective surfaces is greater than a seventh preset threshold, and the seventh preset threshold is greater than the sixth preset threshold.

[0016] Optionally, the light adjusting member is a grating waveguide structure, the grating waveguide structure comprises an optical transmission part and an optical attenuation part, the optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver; The optical transmission part includes a grating part and a first waveguide part, the grating part is arranged around the laser receiver and located above the first waveguide part, the grating part is configured to change the direction of the echo signal from a first position range incident on the first waveguide part, so that the echo signal is totally internally reflected in the first waveguide part, and the diffraction angle of the grating part is greater than the critical angle of the first waveguide part.

[0017] In a second aspect, an embodiment of the present application provides a laser receiving module, comprising at least one laser receiving array, wherein the laser receiving array comprises a plurality of the above-mentioned laser receiving units and a laser receiving board, wherein the plurality of laser receiving units are arranged on the laser receiving board in a matrix arrangement.

[0018] In a third aspect, an embodiment of the present application provides a laser radar, including: The above-mentioned laser receiving module; A laser emission module includes at least one laser emission array, wherein the laser emission array includes multiple laser emitters and a laser emission board, wherein the multiple laser emitters are arranged on the laser emission board in a matrix arrangement, and one laser emitter corresponds to one laser receiver, wherein the optical axis of the laser emitter is spaced a preset distance from the optical axis of the laser receiver.

[0019] In a fourth aspect, an embodiment of the present application provides a smart device, comprising the above-mentioned laser radar.

[0020] The beneficial effects of the embodiments of the present application are as follows: the embodiments of the present application, by providing an optical transmission part and utilizing the performance of the optical transmission part, reflect the echo signal reflected by an object at a relatively close distance back to the laser receiving surface of the laser receiver in the form of total internal reflection, thereby effectively expanding the signal receiving range of the laser receiver, which is conducive to more effectively detecting the distances of different objects at close distances. The embodiments of the present application perform attenuation processing on the echo signal reflected by an object at a medium or short distance, reduce the intensity of the echo signal incident on the laser receiving surface at this time, avoid saturation of the laser receiver, and help improve the discrimination of objects at medium or short distances, thereby improving the detection reliability and accuracy of the laser radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0022] Figure 1 A schematic diagram of the structure of a laser radar provided for related technologies; Figure 2 A schematic diagram of the structure of a laser receiving unit provided in an embodiment of the present application; Figure 3 Based on Figure 1 The schematic diagram of the laser radar receiving the echo signals at relatively close distance and medium-short distance is shown; Figure 4 A schematic diagram of a laser radar receiving echo signals at relatively close distances and medium-short distances provided in an embodiment of the present application; Figure 5 A schematic structural diagram of a laser receiving unit provided in yet another embodiment of the present application, wherein the light adjustment member is a curved prism; Figure 6 A schematic structural diagram of a laser receiving unit provided in yet another embodiment of the present application, wherein the light adjustment member is an array waveguide structure; Figure 7 A schematic structural diagram of a laser receiving unit provided in yet another embodiment of the present application, wherein the light adjustment member is an array waveguide structure; Figure 8 A schematic structural diagram of a laser receiving unit provided in yet another embodiment of the present application, wherein the light adjustment member is an array waveguide structure; Fig. 9 A schematic structural diagram of a laser receiving unit provided in yet another embodiment of the present application, wherein the light adjustment member is an array waveguide structure; Figures 10a to 10eSchematic diagram of the structures of various gratings provided in the embodiments of the present application; Fig.11 A schematic structural diagram of a laser receiving unit provided by yet another embodiment of the present application, wherein the light adjustment member is a grating waveguide structure; Fig.12 A schematic diagram of the change of echo energy with distance provided in an embodiment of the present application; Fig.13 A schematic diagram of the structure of a laser receiving module provided in an embodiment of the present application; Fig.14 An equivalent schematic diagram of a laser receiving module receiving echo signals from different independent channels provided in an embodiment of the present application; Fig.15 An equivalent schematic diagram of a laser receiving module receiving echo signals from different independent channels provided in another embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to facilitate the understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on another element, or there can be one or more centered elements therebetween. When an element is described as "electrically connected" to another element, it can be directly connected to another element, or there can be one or more centered elements therebetween. The orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "bottom", etc. used in this specification is based on the orientation or positional relationship shown in the accompanying drawings, only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0024] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more related listed items. In addition, the technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.

[0025] Many application scenarios have certain standards and requirements for the detection range of LiDAR. LiDAR can be used not only to detect targets at a longer distance, but also to detect targets at a closer distance. In theory, the laser signal emitted by the laser transmitter can be received by the laser receiver, that is, the laser signal emitted by the laser transmitter corresponds to the laser signal received by the laser receiver. Due to the system design of LiDAR, the emission and reception of LiDAR are off-axis designs. In off-axis radars, the following problems are prone to occur: The farther the distance between the target object and the laser radar, the easier it is for the echo signal reflected by the distant target object to fall on the laser receiving surface of the laser receiver. The closer the distance between the target object and the laser radar, the easier it is for the echo signal reflected by the close target object to deviate from the laser receiving surface of the laser receiver.

[0026] When the distance between the target at a relatively close distance and the laser radar is getting closer and closer, for example, a target at 5 meters starts to gradually approach the laser radar, the energy of the echo signal received by the laser receiving surface of the laser receiver becomes weaker and weaker until the echo signal moves out of the laser receiving surface of the laser receiver, thus causing the laser radar to be unable to reliably detect the target at a relatively close distance. It can be understood that a target within 5 meters can be regarded as a relatively close target relative to the laser radar.

[0027] In addition, when the medium-to-close target is getting closer and closer to the laser radar, during the approach process, the echo signal reflected from a certain distance does not deviate from the laser receiving surface of the laser receiver, but the energy of the echo signal at this time is very strong. A highly sensitive laser radar has a signal strength range that can be accurately measured. When the energy of the echo signal exceeds the signal strength range, the laser receiver enters a saturated state. When the laser receiver is close to or in a saturated state, the response of the laser receiver no longer has a linear response relationship with the input echo signal, but a nonlinear response relationship. The nonlinear response relationship weakens the difference between the echo signals, resulting in a decrease in the laser radar's ability to distinguish between different echo signals. It can be understood that targets within 5 to 10 meters can be regarded as medium-to-close distance targets relative to the laser radar.

[0028] See also Figure 1 The laser radar includes a laser transmitter 11 and a laser receiver 12. The laser transmitter 11 is provided with a transmitting lens 13, and the laser receiver 12 is provided with a receiving lens 14. The first optical axis O1 of the transmitting lens 13 and the second optical axis O2 of the receiving lens 14 are separated by a preset distance D.

[0029] The laser radar is used to detect the surrounding environment. The surrounding environment is provided with a first object 15, a second object 16 and a third object 17. The distance of the first object 15 is greater than the distance of the second object 16. Relative to the laser radar, the distance between the first object 15 and the laser radar is 100 meters, the distance between the second object 16 and the laser radar is 30 meters, and the distance between the third object 17 and the laser radar is 50 meters.

[0030] The laser transmitter 11 transmits a first laser signal 111 , a second laser signal 112 and a third laser signal 113 . The first laser signal 111 is incident on the first object 15 , and is reflected by the first object 15 to form a first echo signal 151 . The first echo signal 151 is incident back on the laser receiving surface of the laser receiver 12 .

[0031] The second laser signal 112 is incident on the second object 16 and is reflected by the second object 16 to form a second echo signal 161. Since the second object 16 is a target at a relatively close distance, the second echo signal 161 does not enter the laser receiving surface of the laser receiver 12, but moves out of the laser receiving surface of the laser receiver 12, resulting in the laser radar failing to detect the second object 16.

[0032] The third laser signal 113 is incident on the third object 17 and is reflected by the third object 17 to form a third echo signal 171. Since the third object 17 is a medium-to-short distance target, the energy of the third echo signal 171 is relatively large. Although the third echo signal 171 can be incident back on the laser receiving surface of the laser receiver 12, the laser receiver is in a saturated state and cannot accurately detect the distance between the third object 17 and the laser radar.

[0033] In the process of implementing the embodiments of the present application, the inventors found the following related technologies to overcome the problem of the echo signal at a relatively close distance deviating from the laser receiving surface, which are as follows: ① The related technology sets a prism on the transmitting lens side or the receiving lens side. The prism can deflect the outgoing laser signal at a certain angle or refract the echo signal within a certain distance range to the laser receiving surface of the laser receiver. The disadvantages of this approach are: the assembly requirements of the prism are high, and the process cost and processing cost are high.

[0034] ② The related technology sets a scatterer on the receiving side, which can scatter the echo signal at a short distance back to the laser receiving surface of the laser receiver. The disadvantage of this approach is that the scatterer has a large scattering angle space, which can easily scatter the scattered light to other laser receiving channels, resulting in laser crosstalk and bringing large crosstalk noise to the laser point cloud.

[0035] The embodiment of the present application reflects the echo signal reflected by the object at a relatively close distance back to the laser receiving surface of the laser receiver in the form of total internal reflection, which can effectively expand the signal receiving range of the laser receiver, which is conducive to more effectively detecting the distances of different objects at close distances. At the same time, the embodiment of the present application performs attenuation processing on the echo signal reflected by the object at a medium or short distance, reduces the intensity of the echo signal incident on the laser receiving surface at this time, avoids the saturation phenomenon of the laser receiver, and is conducive to improving the discrimination of objects at medium and short distances, thereby improving the detection reliability and accuracy of the laser radar.

[0036] Hereinafter, the present application provides a laser receiving unit. Figure 2 , the laser receiving unit 200 includes a laser receiver 300 and a light adjusting component 400 .

[0037] The laser receiver 300 is provided with a laser receiving surface for receiving the echo signal reflected by the object. The laser receiver 300 includes a photodiode receiver, an avalanche photodiode receiver, a single photon avalanche photodiode receiver, a silicon photomultiplier diode receiver, a quadrant detector, a focal plane array detector, etc.

[0038] The light adjusting member 400 includes an optical transmission portion 41 and an optical attenuation portion 42 . The optical transmission portion 41 and the optical attenuation portion 42 may be integrally formed or may be two separate optical components.

[0039] The optical transmission part 41 is disposed around the laser receiver 300. In some embodiments, the orthographic projection of the optical transmission part 41 on the laser receiving surface is located on a side of the light adjusting member 400 away from the laser transmitter.

[0040] Please combine Figure 2 , the orthographic projection of the optical transmission part 41 on the laser receiving surface 31 contacts the area where the laser receiver 300 is located. The echo signal that has just deviated from the laser receiving surface 31 can be incident on the optical transmission part 41, and the optical transmission part 41 can perform total internal reflection processing on the echo signal, and then transmit the echo signal processed by total internal reflection to the laser receiving surface of the laser receiver 300. In this way, the embodiment of the present application does not need to design and increase the receiving surface of the laser receiver, and transmits the light spot at a medium or short distance to the receiver, thereby saving design costs.

[0041] The optical transmission part 41 performs total internal reflection processing on the echo signal from the first position range, and then transmits the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver 300. The total internal reflection processing means that the echo signal incident to the optical transmission part 41 is reflected in the optical transmission part 41 and will not be transmitted out of the external environment of the optical transmission part 41.

[0042] The first position range is a range where the distance from the laser radar is less than the first preset distance threshold. The first preset distance threshold is customized by the designer according to the detection requirements of the radar. For example, the first preset distance threshold is 5 meters, and the first position range is 0 to 5 meters, that is, the optical transmission part 41 can perform total internal reflection processing on the echo signal from within 5 meters.

[0043] In some embodiments, the optical transmission part 41 is disposed at a first preset position, and is capable of performing total internal reflection processing on the echo signal from within the first position range, and then transmitting the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver 300 .

[0044] The first preset position is determined by the designer using laser optical path simulation tools, combined with the position of the laser transmitter and the position of the laser receiver. Laser optical path simulation tools include Ansys Zemax OpticStudio, LightTools, ASAP, SeeLight optical system virtual simulation experiment platform, etc. Ansys Zemax OpticStudio uses advanced ray tracing algorithms to simulate the behavior of light in optical systems, and can analyze and optimize the performance of optical components such as lenses and reflectors. LightTools can create, observe, modify and analyze optical systems by drawing graphics, and can directly describe components such as light sources, lenses, reflectors and optical paths in optical systems. ASAP is based on non-sequential ray tracing, which can simulate the performance of optical systems in 3D space, and can simulate and analyze almost any geometric shape and various optical phenomena such as scattering and diffraction. The SeeLight optical system virtual simulation experiment platform has 72 basic optical component models and 8 fiber laser component models, supporting the design and simulation of multiple optical components and complex optical paths.

[0045] For example, if the offset distance between the optical axis of the laser transmitter and the optical axis of the laser receiver is d1, and the echo signal from within a range of 5 meters needs to be processed by total internal reflection, the embodiment of the present application can obtain the position relative to the laser receiver 300 through simulation calculation, and the first preset position is (x1, y1).

[0046] If the offset distance between the optical axis of the laser transmitter and the optical axis of the laser receiver is d2, and the echo signal from within 5 meters needs to be processed by total internal reflection, the embodiment of the present application can obtain the position relative to the laser receiver 300 through simulation calculation, and the first preset position is (x2, y2).

[0047] If the offset distance between the optical axis of the laser transmitter and the optical axis of the laser receiver is d3, and the echo signal from within 4 meters needs to be processed by total internal reflection, the embodiment of the present application can obtain the position relative to the laser receiver 300 through simulation calculation, and the first preset position is (x3, y3).

[0048] It is understandable that those skilled in the art can combine the contents disclosed in the embodiments of the present application with the characteristics of their own products to perform simulation operations on the position and structural characteristics of the optical transmission part 41, and ultimately be able to find a first preset position with the following functions: performing total internal reflection processing on the echo signal from within the first position range.

[0049] The embodiment of the present application sets an optical transmission part 41 and utilizes the performance of the optical transmission part 41 to reflect the echo signal reflected by an object at a closer distance back to the laser receiving surface of the laser receiver in the form of total internal reflection. This can effectively expand the signal receiving range of the laser receiver, which is conducive to more effective detection of the distances of different objects at close distances.

[0050] The optical attenuation unit 42 is disposed on the laser receiving surface of the laser receiver 300 . The optical attenuation unit is used to perform intensity attenuation processing on the echo signal from the second position range, and then transmit the echo signal after intensity attenuation processing to the laser receiving surface of the laser receiver 300 .

[0051] The intensity attenuation process refers to moderately attenuating the intensity of the echo signal incident to the optical attenuation unit 42 to prevent the intensity of the echo signal incident to the laser receiving surface from being too high and causing the laser receiver to enter a saturation state.

[0052] The second position range is a range where the distance from the laser radar is greater than or equal to the second preset distance threshold and less than the third preset distance threshold. The second preset distance threshold and the third preset distance threshold are customized by the designer based on engineering experience. For example, the second preset distance threshold is 5 meters, the third preset distance threshold is 10 meters, and the second position range is a range of 5 meters to 10 meters, that is, the optical attenuation unit 42 is used to perform intensity attenuation processing on the echo signal from the range of 5 meters to 10 meters, and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver 300.

[0053] In some embodiments, the optical attenuation portion 42 is disposed at a second preset position. The second preset position is determined by the designer through simulation using a laser light path simulation tool in combination with the position of the laser transmitter, the position of the laser receiver and the position of the optical transmission portion 41 .

[0054] In some embodiments, please combine Figure 2, the orthographic projection of the optical attenuation part 42 on the laser receiving surface at least partially overlaps with the area where the laser receiver is located. The optical attenuation part 42 can perform intensity attenuation processing on part of the echo signal incident on the laser receiving surface, and then transmit the echo signal after intensity attenuation processing to the laser receiving surface of the laser receiver 300. In this way, the embodiment of the present application does not need to design a larger optical attenuation part 42, but only needs to perform intensity attenuation processing on part of the echo signal incident on the laser receiving surface, thereby saving design costs and meeting the needs of some special scenarios.

[0055] In other embodiments, the orthographic projection of the optical attenuation portion 42 on the laser receiving surface covers the area where the laser receiver 300 is located. The optical attenuation portion 42 can perform intensity attenuation processing on all echo signals incident on the laser receiving surface, and then transmit the echo signals after the intensity attenuation processing to the laser receiving surface of the laser receiver 300. In this way, the embodiments of the present application can ensure that saturation will not occur at any point on the laser receiving surface of the laser receiver 300.

[0056] Relatively speaking, the embodiment of the present application sets an optical attenuation unit 42 and utilizes the characteristics of the optical attenuation unit 42 to attenuate the echo signal reflected by objects at medium and short distances, thereby reducing the intensity of the echo signal incident on the laser receiving surface at this time, avoiding saturation of the laser receiver, and helping to improve the distinction between objects at medium and short distances, thereby improving the detection reliability and accuracy of the laser radar.

[0057] In order to elaborate on the technical effects brought by the laser receiving unit provided in the embodiment of the present application, the embodiment of the present application combines Figure 3 and Figure 4 This is elaborated in detail as follows: See also Figure 3 , the first echo signal 21 from a relatively close distance does not enter the laser receiver 300 after passing through the receiving lens 14, but falls beside the laser receiver 300, resulting in the laser receiver 300 failing to receive the first echo signal 21. The second echo signal 22 from a medium-short distance directly enters the laser receiver 300 after passing through the receiving lens 14. At this time, the intensity of the second echo signal 22 is too large, which easily causes the laser receiver 300 to be in a saturated state.

[0058] See also Figure 4 In the embodiment of the present application, a light adjustment component 400 is additionally provided. On the one hand, the first echo signal 21 is incident on the optical transmission part 41. The optical transmission part 41 performs total internal reflection processing on the first echo signal 21, and then transmits the echo signal processed by total internal reflection to the laser receiving surface of the laser receiver 300. In this way, the embodiment of the present application can effectively expand the signal receiving range of the laser receiver, which is conducive to more effectively detecting the distance of different objects at close range.

[0059] On the other hand, the second echo signal 22 enters the optical attenuation unit 42, and the optical attenuation unit 42 performs intensity attenuation processing on the second echo signal 22, and then transmits the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver 300. In this way, the embodiment of the present application can avoid the saturation phenomenon of the laser receiver, which is beneficial to improve the distinction between objects in medium and short distances.

[0060] In some embodiments, see Figure 5 The optical transmission part 41 includes a first upper surface 41a and a first lower surface 41b which are arranged opposite to each other. The first upper surface 41a is used to receive the echo signal. The first upper surface 41a is provided with a first optical film, and the first lower surface 41b is provided with a second optical film. The reflectivity of the first optical film is less than the first preset threshold, the reflectivity of the second optical film is greater than the second preset threshold, and the second preset threshold is greater than the first preset threshold.

[0061] The first optical film adopts a film material with low reflectivity, and the second optical film adopts a film material with high reflectivity, wherein the materials of the first optical film and the second optical film are customized by the designer according to engineering experience.

[0062] The first optical film includes a single-layer anti-reflection film, a multi-layer anti-reflection film, a broadband anti-reflection film, a V-groove anti-reflection film, a sub-wavelength structure anti-reflection film, a zirconium oxide film layer, an aluminum oxide film layer, a calcium fluoride film layer, a barium fluoride film layer, a polymethyl methacrylate film layer, a cycloolefin polymer film layer, and the like.

[0063] The second optical thin film includes an aluminum film, a silver film, a gold film, a multilayer film based on titanium dioxide and silicon dioxide, a multilayer film based on zinc sulfide and magnesium fluoride, and the like.

[0064] The first preset threshold and the second preset threshold are defined by the designer based on engineering experience. For example, the first preset threshold is any value between 1% and 10%, and the first preset threshold is 2%. The second preset threshold is any value between 90% and 98%, and the second preset threshold is 95%.

[0065] The embodiment of the present application selects a film layer with a reflectivity less than a first preset threshold as the first optical film, and selects a film layer with a reflectivity greater than a second preset threshold as the second optical film. The first optical film can increase the incidence rate of the echo signal from the first position range, so that more echo signals from the first position range can be deflected to the interior of the optical transmission part 41 for total internal reflection processing. The second optical film can reduce the transmittance of the echo signal from the first position range, gather more echo signals to be deflected to the interior of the optical transmission part 41 for total internal reflection processing, thereby improving the signal reception rate of the laser receiver.

[0066] In some embodiments, please combine Figure 5 The optical attenuation portion 42 includes a second upper surface 42a and a second lower surface (not shown) that are arranged opposite to each other. The second upper surface 42a is used to receive the echo signal. The second upper surface 42a is provided with a third optical film, and the second lower surface is provided with a fourth optical film. The reflectivity of the third optical film is greater than the third preset threshold but less than the fourth preset threshold. The reflectivity of the fourth optical film is less than the fifth preset threshold, and the fifth preset threshold is less than the third preset threshold.

[0067] The third optical film adopts a film material with medium-low reflectivity, and the fourth optical film adopts a film material with even lower reflectivity, wherein the materials of the third optical film and the fourth optical film are customized by the designer according to engineering experience.

[0068] The third optical film includes a magnesium fluoride film, a multilayer film composed of silicon dioxide and tantalum pentoxide, a multilayer film composed of titanium dioxide and silicon dioxide, a composite film composed of silver and silicon dioxide, a composite film composed of aluminum and magnesium fluoride, and the like.

[0069] The fourth optical film includes a magnesium fluoride single-layer antireflection film, a multilayer antireflection film composed of titanium dioxide and silicon dioxide, a multilayer antireflection film composed of tantalum pentoxide and silicon dioxide, a gradient refractive index nanostructure antireflection film, a porous silicon antireflection film, and the like.

[0070] The third preset threshold, the fourth preset threshold and the fifth preset threshold are customized by the designer according to engineering experience. For example, the third preset threshold is any value between 5% and 20%, and the fourth preset threshold is any value between 10% and 30%. The fifth preset threshold is any value between 1% and 10%, and the fifth preset threshold is 2%.

[0071] The embodiment of the present application selects a film layer with a reflectivity greater than the third preset threshold but less than the fourth preset threshold as the third optical film, and selects a film layer with a reflectivity less than the fifth preset threshold as the fourth optical film. The third optical film can reduce the incidence rate of the echo signal from the second position range, thereby reducing the energy of the echo signal from the second position range. The fourth optical film can increase the transmittance of the echo signal from the second position range, so that more echo signals can be incident on the laser receiving surface of the laser receiver, thereby avoiding the laser receiver entering a saturation state due to an excessively strong echo signal, which is beneficial to improving the distinction of the point cloud signal.

[0072] The light adjusting component provided in the embodiment of the present application has a variety of product forms. In the following, the embodiment of the present application describes three product forms of the light adjusting component, namely, a curved prism, an arrayed waveguide structure, and a grating waveguide structure. It can be understood that the curved prism, the arrayed waveguide structure, and the grating waveguide structure mentioned below are not intended to cause any improper limitation on the protection scope of the embodiment of the present application, which are as follows: ① When the light adjusting member is a curved prism: The curved prism can not only be used to perform total internal reflection processing on the echo signal from the first position range and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver, but also can be used to perform intensity attenuation processing on the echo signal from the second position range and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver.

[0073] Please combine Figure 5 The curved prism includes an optical transmission part 41 and an optical attenuation part 42, and the optical transmission part 41 and the optical attenuation part 42 are integrally formed. The optical transmission part 41 is arranged around the laser receiver 300, for example, the optical transmission part 41 is located on a side of the curved prism away from the laser transmitter. The optical attenuation part 42 is arranged on the laser receiving surface of the laser receiver 300.

[0074] like Figure 5 As shown, the first echo signal 21 is incident on the optical transmission part 41, and the optical transmission part 41 performs total internal reflection processing on the first echo signal 21, and then transmits the echo signal processed by total internal reflection to the laser receiving surface of the laser receiver 300. The second echo signal 22 is incident on the optical attenuation part 42, and the optical attenuation part 42 performs intensity attenuation processing on the second echo signal 22, and then transmits the echo signal processed by intensity attenuation to the laser receiving surface of the laser receiver 300.

[0075] The incident angle of the echo signal from any incident position of the optical transmission part in the optical transmission part is greater than the critical angle. For example, the critical angle is 41.8°.

[0076] According to the law of refraction, when light is emitted from a denser medium to a less dense medium, there is a critical angle C that satisfies the following conditions: , n1 is the refractive index of the denser medium, and n2 is the refractive index of the less dense medium. If the refractive index of the curved prism is n1=1.5, and the refractive index of air is n2=1, when the echo signal is projected into the air, the critical angle Therefore, when the incident angle of the echo signal from any incident position of the optical transmission part is greater than 41.8° in the optical transmission part, the optical transmission part can perform total internal reflection processing on the echo signal, and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver.

[0077] It is understandable that the embodiment of the present application simulates the curved prism based on the laser light path simulation tool, so that the curved prism has the following function: the incident angle of the echo signal from any incident position of the optical transmission part in the optical transmission part is greater than the critical angle. It is also understandable that this simulation method is well known to people in the industry and will not be repeated here, but the content disclosed in the embodiment of the present application is original to the applicant.

[0078] ② When the light adjustment component is an array waveguide structure: The arrayed waveguide structure can not only be used to perform total internal reflection processing on the echo signal from the first position range and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver, but also can be used to perform intensity attenuation processing on the echo signal from the second position range and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver.

[0079] See also Figure 6 , the array waveguide structure includes an optical transmission part 41 and an optical attenuation part 42, and the optical transmission part 41 and the optical attenuation part 42 are integrally formed. The optical transmission part 41 is arranged around the laser receiver 300, for example, the optical transmission part 41 is located on the side of the array waveguide structure away from the laser transmitter. The optical attenuation part 42 is arranged on the laser receiving surface of the laser receiver 300. It can be understood that the orthographic projection of the optical attenuation part 42 on the laser receiving surface at least partially overlaps with the area where the laser receiver is located. Or, as Fig.11 As shown, the orthographic projection of the optical attenuation portion 42 on the laser receiving surface covers the area where the laser receiver is located.

[0080] At least one first reflection surface 43 is provided in the optical transmission part 41. The at least one first reflection surface 43 is arranged in sequence and tilted in the optical transmission part 41 along the light propagation direction of the echo signal in the optical transmission part 41. The reflectivity of the first reflection surface 43 is greater than the sixth preset threshold. The first reflection surface 43 is used to deflect the echo signal from the first position range back to the optical transmission part 41 for total internal reflection processing, so that the echo signal is incident on the laser receiving surface of the laser receiver. The sixth preset threshold is customized by the designer based on engineering experience. For example, the sixth preset threshold is 60%.

[0081] A plurality of second reflection surfaces 44 are provided in the optical attenuation portion 42. Along the light propagation direction of the echo signal in the optical attenuation portion 42, the plurality of second reflection surfaces 44 are sequentially tilted and arranged behind the first reflection surface 43. In some embodiments, in the optical attenuation portion 42, the mirror distances of any two adjacent second reflection surfaces are equal. The reflectivity of the second reflection surface 44 is less than or equal to the reflectivity of the first reflection surface 43. Exemplarily, the reflectivity of the second reflection surface 44 is 30%.

[0082] When the echo signal from the first position range is incident on the optical transmission part 41, the echo signal propagates laterally in the optical transmission part 41, passes through the first reflection surface 43 during the propagation process, and is reflected to the second reflection surface 44a by the first reflection surface 43. A small part of the echo signal can transmit the second reflection surface 44a, and most of the echo signal is reflected by the second reflection surface 44a back to the laser receiving surface of the laser receiver.

[0083] A small part of the echo signal continues to propagate forward after passing through the second reflection surface 44a. When the echo signal passing through the second reflection surface 44a encounters the second reflection surface 44b, a small part of the echo signal can pass through the second reflection surface 44b, and most of the echo signal is reflected by the second reflection surface 44b back to the laser receiving surface of the laser receiver. And so on.

[0084] The embodiment of the present application can reliably deflect the echo signal to the laser receiving surface of the laser receiver by providing a multi-stage second reflection surface 44 .

[0085] When the echo signal from the second position range is incident on the optical attenuation part 42, when the echo signal encounters the second reflection surface 44, most of the echo signal is transmitted through the second reflection surface 44 and enters the laser receiving surface of the laser receiver, and a small part of the echo signal will be reflected by the second reflection surface 44 and cannot enter the laser receiving surface of the laser receiver. In this way, the embodiment of the present application can also attenuate the echo signal to a certain extent through the second reflection surface 44, slightly reduce the intensity of the echo signal from medium and short distances, thereby avoiding excessive attenuation of the echo signal from medium and short distances.

[0086] like Figure 6 As shown, the array waveguide structure includes a waveguide upper surface 6a and a waveguide lower surface 6b arranged opposite to each other. The waveguide upper surface 6a is used to receive the echo signal. Along the light propagation direction, the first reflection surface and the waveguide upper surface 6a are arranged at an acute angle. The acute angle is [ , ], illustratively, the acute angle is 45°. Along the light propagation direction, the second reflection surface 44 is arranged at an acute angle with the upper surface 6a of the waveguide. The acute angle is [ , ] any value between, for example, the acute angle is 45°.

[0087] It can be understood that the included angle between the second reflecting surface 44 and the waveguide upper surface 6a can be the same as or different from the included angle between the second reflecting surface 44 and the waveguide upper surface 6a.

[0088] In some embodiments, along the direction of light propagation, the reflectivity of the last second reflective surface among the multiple second reflective surfaces is greater than a seventh preset threshold, and the seventh preset threshold is greater than the sixth preset threshold. For example, the seventh preset threshold is 100% or 98%, etc.

[0089] See also Figure 7 , the embodiment of the present application sets the reflectivity of the last second reflection surface 44c to the seventh preset threshold along the light propagation direction of the echo signal in the optical transmission part 41. After the echo signal is reflected by the first reflection surface 43 in the optical transmission part 41, and then processed by multiple second reflection surfaces 44, there is still a remaining echo signal that continues to propagate forward. When the remaining echo signal encounters the last second reflection surface 44c with high reflectivity, the remaining echo signal can be completely or nearly completely deflected to the laser receiving surface of the laser receiver, thereby ensuring that the echo signal can be completely or maximally deflected to the laser receiving surface of the laser receiver, which is beneficial to improving the signal receiving rate of the laser receiver.

[0090] In some embodiments, see Figure 8 In the array waveguide structure, the distances between two adjacent second reflection surfaces 44 are equal, and the projection length of the second reflection surface on the upper surface of the waveguide is equal to the distance between the two adjacent second reflection surfaces 44 .

[0091] The projection length of the second reflection surface 44 on the upper surface of the waveguide is k=h / tanα, where k is the projection length of the second reflection surface on the upper surface of the waveguide, h is the thickness of the array waveguide structure, and α is the angle of the second reflection surface.

[0092] When the distance d between two adjacent second reflection surfaces 44 is equal to the projection length k of the second reflection surface 44 on the waveguide surface, the second reflection surfaces are densely arranged in the optical attenuation part 42, and the echo signal is incident on any position of the optical attenuation part 42. The echo signal at any incident position will encounter the second reflection surface, and the transmittance of the echo signal is affected by the second reflection surface. The echo signal from the second position range can easily encounter the second reflection surface, and the second reflection surface can attenuate the intensity of the echo signal. The attenuated echo signal is then incident on the laser receiving surface of the laser receiver.

[0093] In some other embodiments, see Fig. 9 In the array waveguide structure, the distances between two adjacent second reflection surfaces 44 are equal, and the projection length of the second reflection surface 44 on the upper surface of the waveguide is equal to the target distance, which is the sum of the mirror distance and the preset margin length.

[0094] When k=d+e, e is the preset margin length, k is the projection length of the second reflection surface on the upper surface of the waveguide, and d is the distance between two adjacent second reflection surfaces 44. Compared with the above-mentioned embodiment, the second reflection surfaces are sparsely arranged in the optical transmission part 41 or the optical attenuation part 42, so that the echo signal with an angle less than the preset range value with the optical axis of the laser receiver can be incident on the laser receiving surface of the laser receiver from the area corresponding to the preset margin length, that is, the echo light with a small angle with the optical axis of the laser receiver can directly pass through the array waveguide structure and be received by the laser receiver.

[0095] When the echo signal from a long distance (i.e., the echo signal whose incident angle with the optical axis of the laser receiver forms a small angle) is incident on the laser receiving surface of the laser receiver from the area corresponding to the preset margin length e, the echo signal can directly transmit through the optical attenuation portion 42 and maintain a high energy to be incident on the laser receiving surface of the laser receiver. Therefore, the embodiment of the present application will not attenuate the echo signal with a small angle with the optical axis of the laser receiver to a large extent, thereby ensuring that the echo signal from a long distance maintains a high energy to be incident on the laser receiving surface of the laser receiver, which is beneficial to improving the laser radar's ability to reliably and accurately detect obstacles at a longer distance.

[0096] When the echo signal from medium and short distances (i.e., the echo signal whose incident angle is at a large angle to the optical axis of the laser receiver) is incident on the array waveguide structure, the echo signal is affected by the second reflection surface in the array waveguide, and the echo signal will be reflected multiple times between the second reflection surfaces and then incident on the laser receiving surface of the laser receiver. Therefore, the embodiment of the present application can attenuate the echo signal that is at a large angle to the optical axis of the laser receiver to a certain extent, thereby ensuring that the high-energy echo signal from medium and short distances will not be incident on the laser receiving surface of the laser receiver with higher energy, thereby avoiding saturation of the laser receiver, which is beneficial for the laser radar to reliably and accurately detect obstacles at medium and short distances.

[0097] When the echo signal from a closer distance (due to the light spot offset at a close distance of the off-axis system) will first be incident on at least one first reflection surface in the optical transmission part 41, the echo signal at a closer distance can be incident on the laser receiving surface of the laser receiver after being deflected by the first reflection surface, thereby ensuring that the laser receiver receives the echo signal from a closer distance, so that the laser radar can reliably and accurately detect obstacles at a closer distance.

[0098] In the embodiment of the present application, the first reflecting surface and the second reflecting surface are configured in the light adjusting component according to the following expression k=d+e, so that the light adjusting component can be compatible with reliably and accurately detecting objects at any distance, thereby improving the detection capability of the laser receiving unit in different scenarios.

[0099] ③ When the light adjustment component is a grating waveguide structure: The grating waveguide structure can not only be used to perform total internal reflection processing on the echo signal from the first position range and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver, but also can be used to perform intensity attenuation processing on the echo signal from the second position range and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver.

[0100] Grating waveguide structure includes surface relief grating structure. For details, please refer to Figures 10a to 10d , the surface relief grating structure is a rectangular grating, or, the surface relief grating structure is a tilted grating, or, the surface relief grating structure is a blazed grating, or, the surface relief grating structure is an analog grating. See Fig.10e , the grating waveguide structure is a volume holographic grating structure.

[0101] The grating waveguide structure includes an optical transmission part 41 and an optical attenuation part 42. The optical transmission part 41 is arranged around the laser receiver 300. For example, the optical transmission part 41 is located on a side of the curved prism away from the laser transmitter. The optical attenuation part 42 is arranged on the laser receiving surface of the laser receiver 300.

[0102] See also Fig.11 The optical transmission part 41 includes a grating part 111 and a waveguide part 112. The grating part 111 is arranged around the laser receiver and above the waveguide part 112. The grating part 111 is used to change the direction of the echo signal from the first position range incident on the waveguide part 112, so that the echo signal is totally internally reflected in the waveguide part 112. The diffraction angle of the grating part is greater than the critical angle of the waveguide part.

[0103] When the echo signal from the first position range is incident on the grating portion 111, the grating portion 111 diffracts the echo signal into the waveguide portion 112, changes the original propagation direction of the echo signal, causes the echo signal to undergo total internal reflection in the waveguide portion 112, and finally is incident on the laser receiving surface of the laser receiver.

[0104] When the echo signal from the second position range is incident on the optical attenuation part 42, the optical attenuation part 42 has no grating structure, so the propagation direction of the echo signal does not change. The echo signal is incident on the laser receiving surface of the laser receiver after transmitting the optical attenuation part 42.

[0105] The embodiment of the present application adopts a grating waveguide structure, which can effectively change the propagation direction of the echo signal from the first position range, so that the echo signal from the first position range can reliably undergo total internal reflection in the waveguide portion 112, and can then reliably enter the laser receiving surface of the laser receiver.

[0106] In order to verify the benefits of the laser receiving unit provided in the embodiment of the present application, the embodiment of the present application combines Fig.12 To explain this: like Fig.12 As shown, the closer distance is the distance from r1 to r2.

[0107] The laser radar detects the first object. The energy change of the echo signal reflected by the first object is as follows: Fig.12 As shown in curve 121, in the related art, the energy of the echo signal is relatively weak within the distance between r1 and r2, and the energy of the echo signal detected by the laser receiver does not exceed the detection threshold, resulting in the laser receiver being unable to identify the valid point cloud points detected at a closer distance. As shown in curve 122, in the embodiment of the present application, the energy of the echo signal shows a significant increase within the distance between r1 and r2, and exceeds the detection threshold, and the laser receiver is able to identify the valid point cloud points detected at a closer distance, which illustrates that the embodiment of the present application deflects the echo signal reflected at a closer distance back to the laser receiving surface, thereby more reliably and accurately detecting objects at a closer distance.

[0108] The medium and short distance is from r2 to r3. Within the distance between r2 and r3, the energy of the echo signal shown by curve 121 is higher than the energy of the echo signal shown by curve 122, which shows that the embodiment of the present application attenuates the echo energy at medium and short distances, which can avoid excessive saturation of the laser receiver and help improve the distinction of the point cloud.

[0109] The laser radar detects the second object. The energy change of the echo signal reflected by the second object is as follows: Fig.12 Curve 123 is an energy change curve of an echo signal generated based on the related art, and curve 124 is an energy change curve of an echo signal generated based on the embodiment of the present application. It can be understood that the analysis of curves 123 and 124 is as described above and will not be repeated here.

[0110] As another aspect of the present application, the present application provides a laser receiving module. Fig.13 The laser receiving module 130 includes at least one laser receiving array, wherein the receiving array can be a receiving linear array or a receiving planar array. The laser receiving array includes a plurality of laser receiving units 200 and a laser receiving board 131 described in the above-mentioned embodiments. The plurality of laser receiving units 200 are arranged on the laser receiving board 131 in a matrix arrangement.

[0111] like Fig.13As shown, the laser receiving plate 131 is provided with a near-field receiving area 132 and a far-field receiving area 133, and a plurality of laser receiving units 200 are arranged in a matrix arrangement in the near-field receiving area 132 and the far-field receiving area 133 of the laser receiving plate 131, wherein the near-field receiving area 132 is used for arranging the receiving units 200 provided with light adjustment components, and the far-field receiving area 133 is used for arranging the laser receivers without light adjustment components.

[0112] As an example, multiple adjacent laser receivers may share the same light adjustment member, wherein the multiple laser receivers may be arranged in a row (e.g., 1xn, n≥1), a column (e.g., nx1, n≥1), or a block (e.g., 3x3, 4x3, 4x4), etc. Fig.14 , when the laser radar is arranged in a left-right layout for transmission and reception, taking the example that each row of laser receivers shares the same light adjustment component in the near-field receiving area 132, the row of laser receivers is used to receive the echo signal 141 transmitted by the same light adjustment component, and process the echo signal according to the method of the above embodiment. Among them, it can be understood that. Since different rows of laser receiving units 200 correspond to different light adjustment components, optical crosstalk between different rows can be avoided, thereby improving detection reliability. It can be understood that when the laser radar is arranged in an up-down layout for transmission and reception, each column of laser receivers can also share the same light adjustment component in the near-field receiving area 132, and the column of laser receivers is used to receive the echo signal 141 transmitted by the same light adjustment component, and process the echo signal according to the method of the above embodiment.

[0113] As another example, at least two adjacent rows of receivers may share the same light adjusting member, or at least two columns of receivers may share the same light adjusting member, or at least two adjacent blocks of receivers may share the same light adjusting member. Fig.15 , at least two rows of laser receivers are spatially arranged to form a laser receiving array, and are used to receive the echo signal 151 transmitted by the same optical adjustment component. Specifically, after the echo signal 151 enters the optical adjustment component, it is transmitted to at least two rows of laser receivers to receive and form a sub-echo signal. Through this structural design, the receivers of adjacent rows, columns, or blocks in the array can share an independent channel (i.e., share the same optical adjustment component), and the laser receiving units at different positions in the laser receiving array respectively receive the sub-echo signals from the corresponding channels. With this structure, the embodiment of the present application can further realize the multiplexing of the optical adjustment components of the laser receivers in adjacent rows, columns, or blocks, and use fewer optical adjustment components to meet the detection requirements of the light spot offset of the near-field receivers at different positions.

[0114] As yet another aspect of the embodiments of the present application, the embodiments of the present application provide a laser radar that can be applied to any type of smart device, including vehicles, drones, robots, etc.

[0115] The laser radar includes a laser receiving module and a laser emitting module. The laser emitting module includes at least one laser emitting array. The laser emitting array includes multiple laser emitters and a laser emitting board. The multiple laser emitters are arranged on the laser emitting board in an array arrangement. The array arrangement may be, for example, a matrix arrangement. The optical axis of the laser emitter is spaced a preset distance from the optical axis of the laser receiver. The correspondence between the laser emitter and the receiver may be one laser emitter corresponding to one laser receiver, one emitter corresponding to multiple laser receivers, multiple laser emitters corresponding to one laser receiver (for example, one laser emitting block corresponding to one laser receiver), or multiple laser emitters corresponding to multiple laser receivers (for example, one laser emitting block corresponding to one laser receiving block). The correspondence between the laser emitter and the laser receiver is not limited in this application.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Under the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present application as described above, which are not provided in detail for the sake of simplicity. Although the present application has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A laser receiving unit, characterized in that: It includes a laser receiver and a light adjusting component, wherein the light adjusting component includes an optical transmission part and an optical attenuation part; The optical transmission part is arranged around the laser receiver, and is configured to perform total internal reflection processing on the echo signal from the first position range, and then transmit the echo signal after the total internal reflection processing to the laser receiving surface of the laser receiver; The optical attenuation unit is disposed on the laser receiving surface of the laser receiver, and is configured to perform intensity attenuation processing on the echo signal from the second position range, and then transmit the echo signal after the intensity attenuation processing to the laser receiving surface of the laser receiver.

2. The laser receiving unit according to claim 1, characterized in that: The orthographic projection of the optical transmission portion on the laser receiving surface is located on a side of the light adjusting component away from the laser emitter.

3. The laser receiving unit according to claim 1, characterized in that: The optical transmission part includes a first upper surface and a first lower surface arranged opposite to each other, the first upper surface is configured to receive an echo signal, wherein the first upper surface is provided with a first optical film, the first lower surface is provided with a second optical film, the reflectivity of the first optical film is less than a first preset threshold, the reflectivity of the second optical film is greater than a second preset threshold, and the second preset threshold is greater than the first preset threshold.

4. The laser receiving unit according to claim 1, characterized in that: The orthographic projection of the optical attenuation portion on the laser receiving surface at least partially overlaps with the area where the laser receiver is located; or, The orthographic projection of the optical attenuation portion on the laser receiving surface covers the area where the laser receiver is located.

5. The laser receiving unit according to claim 4, characterized in that: The optical attenuation portion includes a second upper surface and a second lower surface that are arranged opposite to each other, the second upper surface is configured to receive an echo signal, wherein the second upper surface is provided with a third optical film, the second lower surface is provided with a fourth optical film, the reflectivity of the third optical film is greater than a third preset threshold but less than a fourth preset threshold, the reflectivity of the fourth optical film is less than a fifth preset threshold, and the fifth preset threshold is less than the third preset threshold.

6. The laser receiving unit according to any one of claims 1 to 5, characterized in that: The light adjusting member is a curved prism, and the curved prism includes the optical transmission part and the optical attenuation part. The optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver.

7. The laser receiving unit according to claim 6, characterized in that: The incident angle of the echo signal from any incident position of the optical transmission portion in the optical transmission portion is greater than the critical angle.

8. The laser receiving unit according to any one of claims 1 to 5, characterized in that: The light adjusting member is an array waveguide structure, and the array waveguide structure includes the optical transmission part and the optical attenuation part. The optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver.

9. The laser receiving unit according to claim 8, characterized in that: At least one first reflection surface is provided in the optical transmission part, and the at least one first reflection surface is tiltedly arranged in sequence in the optical transmission part along the light propagation direction of the echo signal in the optical transmission part, and the reflectivity of the first reflection surface is greater than a sixth preset threshold value; A plurality of second reflection surfaces are provided in the optical attenuation portion. Along the light propagation direction of the echo signal in the optical attenuation portion, the plurality of second reflection surfaces are arranged in sequence and tilted behind the first reflection surface, and the reflectivity of the second reflection surface is less than or equal to the reflectivity of the first reflection surface.

10. The laser receiving unit according to claim 9, characterized in that: The array waveguide structure comprises a waveguide upper surface and a waveguide lower surface arranged opposite to each other, wherein the waveguide upper surface is configured to receive an echo signal, and along the propagation direction of the light, the first reflection surface is arranged at an acute angle with the waveguide upper surface, and / or the second reflection surface is arranged at an acute angle with the waveguide upper surface, wherein the acute angle is [ , ] any value between ].

11. The laser receiving unit according to any one of claims 1 to 5, characterized in that: The light adjusting member is a grating waveguide structure, and the grating waveguide structure includes an optical transmission part and an optical attenuation part, the optical transmission part is arranged around the laser receiver, and the optical attenuation part is arranged on the laser receiving surface of the laser receiver; The optical transmission part includes a grating part and a first waveguide part, the grating part is arranged around the laser receiver and located above the first waveguide part, the grating part is configured to change the direction of the echo signal from a first position range incident on the first waveguide part, so that the echo signal is totally internally reflected in the first waveguide part, and the diffraction angle of the grating part is greater than the critical angle of the first waveguide part.

12. A laser receiving module, characterized in that: It comprises at least one laser receiving array, wherein the laser receiving array comprises a plurality of laser receiving units and a laser receiving board according to any one of claims 1 to 11, and the plurality of laser receiving units are arranged on the laser receiving board in an array arrangement.

13. A laser radar, characterized in that: include: The laser receiving module as claimed in claim 12; The laser emission module includes at least one laser emission array, wherein the laser emission array includes a plurality of laser emitters and a laser emission board, wherein the plurality of laser emitters are arranged on the laser emission board in an array arrangement, wherein the optical axis of the laser emitter is spaced a preset distance from the optical axis of the laser receiver.

14. A smart device, characterized in that: Comprising a laser radar as described in claim 13.

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