CN116840846A - Laser radar - Google Patents

Abstract

The present application provides a laser radar, comprising: a transmitting unit configured to provide a probe beam, the probe beam being reflected by the target object to form an echo beam; a receiving unit configured to receive the echo beam within a reception field of view; an attenuation unit configured to attenuate ambient light outside a reception field of view; and a scanning unit configured to perform spatial scanning using the probe beam and the echo beam. When the laser radar provided by the application works, the transmitting unit is used for transmitting the detection light beam, the scanning unit changes the direction of the detection light beam and irradiates the three-dimensional space to scan the three-dimensional space; the detection light beam is reflected by the object in the three-dimensional space to form an echo light beam, the echo light beam irradiates the scanning unit, the scanning unit transmits the echo light beam to the receiving unit, the receiving unit is configured to receive the echo light beam in a receiving view field, the attenuation unit is configured to attenuate the ambient light received by the receiving unit outside the receiving view field, the signal-to-noise ratio is improved, and further the range finding performance of the laser radar is improved.

Description

Laser radar

Technical Field

The application relates to the field of environmental perception, in particular to a laser radar.

Background

Laser radar (LIDAR) is a radar system that detects feature quantities such as the position and speed of a target by emitting a laser beam, and plays important roles such as road edge detection, obstacle recognition, and real-time localization and mapping (SLAM) in automatic driving. The laser radar has the characteristics of high resolution, good concealment, strong active interference resistance, good detection performance, small volume, light weight and the like, and is applied to the technical field of automatic driving, and the laser radar is indispensable as a core sensor for distance sensing in the field of automatic driving.

Lidar is an important sensor for sensing information around a vehicle, and detection field and scanning accuracy are important parameters.

One aspect that determines lidar ranging performance is signal-to-noise ratio, while ambient light is a major component of noise. In other words, the environmental light received by the laser radar can be effectively reduced, i.e. the ranging performance of the laser radar can be improved.

Disclosure of Invention

The application provides a laser radar which is used for effectively reducing the ambient light received by the laser radar, improving the signal to noise ratio and improving the ranging performance of the laser radar.

In order to solve the above problems, the present application provides a lidar comprising: an emission unit configured to provide a probe beam, the probe beam being reflected by a target object to form an echo beam; a receiving unit configured to receive the echo beam within a reception field of view; an attenuation unit configured to attenuate ambient light outside the reception field of view; and a scanning unit configured to perform spatial scanning using the probe beam and the echo beam.

Optionally, the attenuation unit is located upstream of the receiving unit on the transmission path of the echo beam, and is configured to absorb ambient light or deflect the ambient light transmission direction.

Optionally, the attenuation unit includes: and a focal length extension unit configured to extend a focal length of the received echo beam.

Optionally, the laser radar further includes: a spectroscopic device located downstream of the transmission path of the transmitting unit, configured to transmit the probe beam and irradiate the probe beam toward a target object, the spectroscopic device being further configured to reflect the echo beam to the receiving unit; the focal length extension unit is positioned between the beam splitting device and the receiving unit on the transmission path of the echo beam.

Optionally, the attenuation unit comprises an ambient light reflecting structure.

Optionally, the ambient light reflecting structure comprises a saw tooth like structure.

Optionally, the surface of the serrated structure is perpendicular to the ambient light transmission direction.

Optionally, the ambient light reflecting structure includes: a light absorbing layer; and the plurality of cone-shaped reflectors are arranged on the light absorption layer at intervals and are configured to reflect the ambient light to the light absorption layer.

Optionally, the ambient light reflecting structure further comprises: and a reflection enhancer, located between the reflectors on the light absorbing layer, configured to increase the number of times ambient light is reflected.

Optionally, the attenuation unit comprises a porous structure configured to absorb ambient light.

Optionally, the surface of the ambient light reflecting structure or the porous structure is subjected to at least one of electrophoresis, anodic oxidation, micro-arc or blackening treatment.

Optionally, the laser radar further includes: and the optical machine unit is configured to transmit the detection light beam to the scanning unit and transmit the echo light beam to the receiving unit.

Optionally, the optical machine unit includes: a support configured to transmit the probe beam and the echo beam and support the scanning unit; a reflection section configured to reflect the probe beam to the scanning unit and reflect the echo beam to the supporting section; the attenuation unit is positioned between the supporting part and the reflecting part.

Optionally, the laser radar further includes: the receiving module comprises a transmitting unit and a receiving unit; the transceiver modules are arranged side by side and at intervals on one side of the supporting part, which is away from the reflecting part.

Optionally, the support part includes: a plurality of optical channels arranged along transmission paths of the probe beam and the echo beam; the optical units are correspondingly arranged in the optical channels.

Optionally, the scanning unit includes: a fixing part fixed on the top of the supporting part; and a galvanometer unit obliquely disposed on top of the fixing part and configured to reflect the probe beam and the echo beam by the galvanometer unit.

Compared with the prior art, the technical scheme of the application has the following advantages:

the laser radar provided by the application comprises a transmitting unit, a receiving unit and a processing unit, wherein the transmitting unit is configured to provide a detection beam, and the detection beam is reflected by a target object to form an echo beam; a receiving unit configured to receive the echo beam within a reception field of view; an attenuation unit configured to attenuate ambient light outside the reception field of view; and a scanning unit configured to perform spatial scanning using the probe beam and the echo beam. When the laser radar provided by the embodiment of the application works, the transmitting unit is used for transmitting the detection light beam, the scanning unit changes the direction of the detection light beam, irradiates the three-dimensional space and scans the three-dimensional space; the detection light beam is reflected by an object in a three-dimensional space to form an echo light beam, the echo light beam irradiates the scanning unit, the scanning unit transmits the echo light beam to the receiving unit, the receiving unit is configured to receive the echo light beam in a receiving view field, the attenuation unit is configured to attenuate the ambient light received by the receiving unit outside the receiving view field, the signal-to-noise ratio is improved, and then the range finding performance of the laser radar is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only embodiments of the present application, and that other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of a beam transmission path of a lidar according to an embodiment of the present application;

FIG. 2 is a schematic view of a laser radar according to an embodiment of the present application;

FIG. 3 is a schematic structural view of a first embodiment of a lidar attenuating unit according to an embodiment of the present application;

FIG. 4 is a schematic diagram of another configuration of a first embodiment of a lidar attenuating unit according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a second embodiment of a lidar attenuating unit according to an embodiment of the present application;

FIG. 6 is a schematic diagram of a third embodiment of a lidar attenuating unit according to an embodiment of the present application;

FIG. 7 is an enlarged partial schematic view at E in FIG. 6;

fig. 8 is a schematic structural view of a fourth embodiment of a lidar attenuating unit according to an embodiment of the present application;

FIG. 9 is an enlarged partial schematic view at F in FIG. 8;

FIG. 10 is a top view of a laser radar hidden upper motherboard module in accordance with an embodiment of the present application;

fig. 11 is an exploded view of a lidar according to an embodiment of the present application.

Detailed Description

As known from the background art, one aspect of determining the ranging performance of the lidar is the signal-to-noise ratio, and the ambient light is the main component of noise, so that the ambient light received by the lidar can be effectively reduced, i.e. the ranging performance of the lidar can be improved.

In order to effectively reduce the ambient light received by the laser radar and improve the ranging performance of the laser radar, the embodiment of the application provides the laser radar which comprises the following components: an emission unit configured to provide a probe beam, the probe beam being reflected by a target object to form an echo beam; a receiving unit configured to receive the echo beam within a reception field of view; an attenuation unit configured to attenuate ambient light outside the reception field of view; and a scanning unit configured to perform spatial scanning using the probe beam and the echo beam.

The following description of the embodiments of the present application will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It should be noted that the direction or positional relationship referred to in this specification is based on the direction or positional relationship shown in the drawings, and is merely for convenience of description and simplification of description, and does not indicate or imply that the apparatus referred to must have a specific direction, and is configured in a specific direction, and thus should not be construed as limiting the application.

An embodiment of the present application provides a lidar, and referring to fig. 1 and fig. 2, fig. 1 shows a schematic diagram of a beam transmission path of the lidar according to the embodiment of the present application, and fig. 2 shows a schematic diagram of a structure of the lidar according to the embodiment of the present application.

The laser radar includes: an emission unit 20 configured to provide a probe beam, which is reflected by the object to form an echo beam; a receiving unit 130 configured to receive the echo beam within a reception field of view; an attenuation unit 10 configured to attenuate ambient light outside the reception field of view; and a scanning unit 300 configured to perform spatial scanning using the probe beam and the echo beam.

When the laser radar provided by the embodiment of the application works, the emitting unit 20 is used for emitting the detection light beam, the scanning unit 300 changes the direction of the detection light beam, irradiates the three-dimensional space, and scans the three-dimensional space; the probe beam is reflected by an object in three-dimensional space to form an echo beam, the echo beam irradiates the scanning unit 300, the scanning unit 300 transmits the echo beam to the receiving unit 130, the receiving unit 130 is configured to receive the echo beam in a receiving view field, and the attenuation unit 10 is configured to attenuate the ambient light received by the receiving unit outside the receiving view field, so that the signal-to-noise ratio is improved, and further the radar ranging performance is improved.

The transmitting unit 20 includes: a light emitting plate (not shown in the drawings) including a plurality of light emitting units.

In this embodiment, the emission plate has a laser (i.e., a light emission unit) thereon, and the laser includes an Edge Emission Laser (EEL), and the optical axis direction of the probe beam is parallel to the surface of the emission plate when the emission unit 20 is operated. In other embodiments, the laser may also be a Vertical Cavity Surface Emitting Laser (VCSEL), and accordingly, the probe beam is perpendicular to the surface of the emitter plate when the emitter unit is in operation.

As an example, the number of the lasers is multiple, so that the detection resolution of the laser radar is higher, the detection performance of the laser radar is improved, and the lasers are distributed on the surface of the transmitting plate at intervals. The multiple lasers generate multiple probe beams, and when the transmitting unit 20 works, the multiple lasers in the transmitting plate are sequentially turned on in a round-robin mode to transmit the probe beams, i.e. the multiple lasers in the transmitting plate transmit the probe beams in a time-sharing mode.

The radiating plate is a PCB, the single side of the radiating plate is covered with copper, and the back of the radiating plate is exposed to copper, so that heat dissipation is facilitated, and the laser can be ensured to work in a reasonable temperature range.

The receiving unit 130 includes: a receiving plate (not shown in the drawings) including a plurality of light receiving units.

In this embodiment, the receiving board has a plurality of detectors (i.e., light receiving units) thereon for receiving the echo beams, and the detectors include avalanche photodiodes (Avalanche Photo Diode, APD), silicon photomultiplier (SiPM), or Single Photon Avalanche Diodes (SPAD). When the receiving plate works, a plurality of detectors in the receiving plate are sequentially started to receive echo light beams in a round robin mode, namely the plurality of detectors receive the echo light beams in a time sharing mode.

It should be noted that, in other embodiments, multiple lasers may emit probe beams simultaneously, and corresponding multiple detectors receive echo beams simultaneously.

The scanning unit 300 changes the direction of the beam, irradiates the beam to the three-dimensional space, scans the three-dimensional space, and obtains an echo beam after the probe beam is reflected by an object in the three-dimensional space, irradiates the scanning unit 300, and the scanning unit 300 reflects the echo beam to be received by the receiving unit 130.

The lidar further comprises: a beam splitter 160, located downstream of the transmitting unit 20 on the transmission path of the probe beam, for transmitting the probe beam and irradiating the probe beam toward the target, the beam splitter 160 being further configured to reflect the echo beam to the receiving unit 130. The spectroscopic device 160 can improve the reliability of the transmission/reception alignment of the receiving unit 130 and the transmitting unit 20 in the coaxial transmission/reception optical system.

In this embodiment, the light-splitting device 160 may be a polarizing prism (polarizing Beam Splitter, PBS) or a polarizing beam splitter.

The attenuation unit 10 is located upstream of the receiving unit 130 on the transmission path of the echo beam for absorbing ambient light or deflecting the direction of the ambient light transmission, such as causing diffuse reflection of the ambient light or reflection to the exterior of the lidar.

In this embodiment, the attenuation unit 10 includes an ambient light reflecting structure. The ambient light reflecting structure is used for reflecting ambient light, attenuating the ambient light received by the receiving unit outside the receiving view field, improving the signal to noise ratio and further improving the range finding performance of the laser radar.

As shown in fig. 3, a schematic structural diagram of a first embodiment of the attenuation unit is illustrated.

Specifically, the ambient light reflecting structure as the attenuation unit 10 includes a saw-tooth structure 11, and a surface of the saw-tooth structure 11 is used for reflecting ambient light. Specifically, the reflecting surface is the a surface in fig. 3.

In this embodiment, the surface of the serrated structure 11 is perpendicular to the ambient light transmission direction. The surface A of the sawtooth-shaped structure 11 is perpendicular to the ambient light, so that the ambient light can be reflected to the outside of the laser radar, the laser radar is prevented from receiving the ambient light, and the ranging performance of the laser radar is improved.

In this embodiment, the saw-tooth structure 11 includes, in addition to the reflective surface (a surface), a B surface connecting the reflective surfaces, and since the B surface is not used for reflecting ambient light, there may be various angular relationships between the B surface and the reflective surface, which is not limited by the present application.

It should be noted that, the ambient light mainly comes from sunlight, and as the angle of the sunlight changes, the ambient light outside the receiving field of view (stray field of view) of the receiving unit changes, so that the transmission direction in which the ambient light is strongest can be obtained, and the reflection surface (a surface) of the sawtooth structure is perpendicular to the direction.

In other embodiments, as shown in fig. 4, the surface of the serrated structure may not be perpendicular to the transmission direction of the ambient light, so that the debugging difficulty of the serrated structure in the laser radar may be reduced, and the assembly efficiency of the laser radar may be improved.

In this embodiment, the surface of the saw-tooth structure 11 is subjected to at least one of electrophoresis, anodic oxidation, micro-arc or blackening treatment to form a surface treatment layer (not shown in the figure). The surface treatment layer can absorb and reduce the scattering of the ambient light to the greatest extent, can absorb part of the ambient light, and effectively inhibit the ambient light noise caused by stray view fields.

In this embodiment, the material of the serrated structure 11 is a porous structure that absorbs ambient light. For example, the porous material includes a sponge. Ambient light propagates to the aperture surface, a portion is absorbed, and a portion is scattered to surrounding apertures for further absorption, thereby effectively attenuating ambient light in stray fields of view outside the receiving field of view.

As shown in fig. 5, a schematic structural diagram of a second embodiment of the attenuation unit is illustrated.

In this embodiment, the attenuation unit 10 comprises a porous structure 12 for absorbing ambient light.

Ambient light propagates to the aperture surfaces of the porous structure 12, with a portion being absorbed and a portion scattered to surrounding apertures being further absorbed, thereby effectively suppressing ambient light in stray fields of view outside the receiving field of view.

In this embodiment, the material of the porous structure 12 comprises a sponge.

The surface of the porous structure 12 is subjected to at least one of electrophoresis, anodic oxidation, micro-arc or blackening treatment to form a surface treatment layer (not shown).

Fig. 6 and 7, fig. 7 is a partially enlarged schematic view of fig. 6 at E, illustrating a schematic structure of a third embodiment of the attenuation unit.

Specifically, the ambient light reflecting structure as the attenuation unit 10 includes: a light absorbing layer 31; and a plurality of cone-shaped reflectors 32 arranged on the light absorption layer 31 at intervals for reflecting a part of the ambient light to the light absorption layer 31 and a part of the ambient light to the outside of the laser radar.

When the ambient light is incident to the ambient light reflecting structure, the ambient light projected into the gap of the reflector 32 is reflected repeatedly on the outer surface of the adjacent reflector 32 (as shown in fig. 7), most of the energy of the ambient light is reflected in the process of being reflected, part of the energy of the ambient light is absorbed by the reflecting surface, the contact times between the ambient light and the reflector 32 are increased, so that the amount of the ambient light absorbed by the reflector 32 is increased, the energy of the ambient light is continuously attenuated, the energy reflected to the light absorbing layer 31 is further reduced, the light absorbing layer 31 is easy to absorb the ambient light, the ambient light noise received by the radar can be reduced, the signal to noise ratio is improved, and the ranging performance of the laser radar can be improved.

In this embodiment, the material of the light absorbing layer 31 is a Black Oxide film (Black Oxide) formed by blackening treatment.

In other embodiments, the material of the light absorbing layer may also be a porous structure, such as a sponge-like porous structure, for absorbing ambient light. The ambient light propagates to the hole surfaces of the porous structure, a part of the ambient light is absorbed, and a part of the ambient light is scattered to surrounding holes to be further absorbed, so that the ambient light in the stray field outside the receiving field is effectively restrained.

In this embodiment, the reflector 32 may be made of metal. In other embodiments, the reflector may be other crystals that are easily formed.

In the present embodiment, the specific number of reflectors 32 is not limited. To facilitate multiple reflections of the light beam between reflectors 32, reflectors 32 may be in the form of sheets, needles, or reverse cones in alternative arrangements.

In this embodiment, the width of the reflector 32 may be 1 to 500nm, the length of the reflector 32 may be 0.01 to 1mm, and the distance between two adjacent reflectors 32 may be 0.001 to 1mm. Of course, embodiments of the present application are not limited to the specific shape, width, length, and spacing of the reflectors 32. So configured, the reflector 32 is denser, facilitating attenuation of ambient light.

It should be noted that, the surface of the ambient light reflecting structure is subjected to at least one of electrophoresis, anodic oxidation, micro-arc or blackening treatment, so that the surface of the ambient light reflecting structure forms a surface treatment layer (not shown in the figure). Specifically, the surface treatment is formed on the surfaces of the absorption layer 31 and the reflector 32.

The surface treatment layer can absorb part of the ambient light, further reduce the reflection of the ambient light between the reflectors 32, and also improve the absorption capacity of the absorption layer for the ambient light.

As shown in fig. 8 and 9, fig. 9 is a partially enlarged schematic view of fig. 8 at F, illustrating a schematic structure of a fourth embodiment of the attenuation unit.

In this embodiment, the fourth embodiment of the attenuation unit is the same as the third embodiment, and the difference is that:

the ambient light reflecting structure as the attenuation unit 10 further includes: a reflection enhancer 33, located between the reflectors 32 on the light absorbing layer 31, for increasing the number of times ambient light is reflected.

When the ambient light is incident into the ambient light reflecting structure, the ambient light is projected into the gap of the reflector 32 and is reflected for multiple times on the outer surface of the adjacent reflector 32 (as shown in fig. 9), most of the energy of the ambient light is reflected in the process of being reflected, and part of the energy of the ambient light is absorbed by the reflecting surface, the reflection enhancing body 33 increases the reflection times of the ambient light between the reflectors 32, so that the amount of the ambient light absorbed by the reflectors 32 and the reflection enhancing body 33 increases, the energy of the ambient light is continuously attenuated, the energy of the ambient light reflected to the light absorbing layer is further reduced, the ambient light received by the laser radar can be reduced, the signal to noise ratio is improved, and the ranging performance of the laser radar can be improved.

In this embodiment, the attenuation unit 10 further includes: the focal length extension unit 151 is configured to extend the focal length of the received echo beam, effectively reduce the ambient light received by the laser radar, improve the signal-to-noise ratio, and further improve the radar ranging performance.

In this embodiment, the focal length extension unit 151 includes: a negative lens.

Specifically, the focal length extension unit 151 is located between the spectroscopic device 160 and the receiving unit 130 on the transmission path of the echo beam. After the echo beam is reflected by the beam splitter 160, the focal length is prolonged by the focal length prolonging unit 151, so that the background noise caused by the ambient light can be effectively reduced under the same clear aperture.

In this embodiment, the focal length extension unit 151 further includes: a turning structure (not shown) for reflecting the echo beam.

In this embodiment, the turning structure includes a mirror.

In the transmission direction of the echo beam, the deflecting structure is located upstream or downstream of the focal length extending unit 151.

The lidar further comprises: a transceiver module 100, said transceiver module 100 comprising said transmitting unit 20 and a receiving unit 130. Specifically, the transmitting unit 20 and the receiving unit 130 are fixed to the transceiver module 100.

The transmitting unit 20 and the receiving unit 130 are components of the transceiver module 100, and the transmitting unit 20 and the receiving unit 130 are arranged in a modularized manner, so that the space structure of the transceiver module 100 is reasonably arranged, the structure of the transceiver module 100 is compact, and the integration level is high; in addition, the transmitting unit 20 and the receiving unit 130 can be assembled and debugged independently, which is favorable for mass production of the transceiver module 100, reduces the cost of the transceiver module 100, and is easy to detach the failed transceiver module 100 from the shell for replacement when the transceiver module 100 fails, reduces the maintenance difficulty and improves the maintenance efficiency.

In this embodiment, the number of transceiver modules 100 is plural, and the plurality of transceiver modules 100 can expand the scanning range of the lidar, thereby expanding the field of view of the lidar. As an example, three transceiver modules 100 are shown. In other embodiments, the number of transceiver modules may be two or more than three.

The lidar further comprises: the optical-mechanical module 200 is configured to transmit the probe beam to the scanning unit 300 and transmit the echo beam to the receiving unit 130.

In this embodiment, the optical machine module 200 includes a supporting portion 201 for transmitting the probe beam and the echo beam and supporting the scanning unit 300; a reflecting portion 202 for reflecting the probe beam to the scanning unit 300 and reflecting the echo beam to the supporting portion 201.

When the lidar works, the optical machine module 200 is used for optically shaping the probe beam, so that the probe beam irradiates the scanning unit 300; and the opto-mechanical module 200 may also be used to optically shape the echo beam so that the echo beam can pass through the light-transmitting portion of the transceiver module 100.

The supporting part 201 is used for collimating the detection light beam and irradiating the detection light beam to the reflecting part 202; the supporting portion 201 is configured to converge the echo beam reflected by the reflecting portion 202, and return to the transceiver module 100.

Specifically, the supporting portion 201 includes: a plurality of optical channels (not shown) disposed along the transmission paths of the probe beam and the echo beam; a plurality of groups of optical units (not shown) are correspondingly arranged in each optical channel.

The optical channels provide installation space for the optical units, and the optical channels are separated and isolated from each other, so that when the laser radar works, the detection beam or the echo beam in one optical channel can be prevented from influencing the detection beam or the echo beam in the other optical channel, and the performance of the laser radar is improved.

The optical unit includes: a negative lens 152 and a convex lens 153 are located downstream of the spectroscopic unit on the transmission path of the probe beam.

The optical unit is used for collimating the detection light beam passing through the beam splitting unit and converging the echo light beam.

The support 201 includes: a frame body including a bottom plate (not shown in the figure) and a top plate 2011 spaced apart in a vertical direction, and a side plate 2012 located between the bottom plate and the top plate such that a front end and a rear end of the frame body communicate.

The supporting portion 201 further includes: a plurality of partition plates (not shown in the figure) are spaced between the side plates 2012, and the bottom plate (not shown in the figure), the top plate 2011, the side plates 2012 and the partition plates enclose an optical channel, or the bottom plate, the top plate 2011 and the partition plates enclose an optical channel, and the extending direction of the optical channel penetrates through the front end and the rear end of the frame body.

The optical unit is configured to optically shape the probe beam and the echo beam to increase the energy density of the beam, thereby increasing the signal-to-noise ratio of the signal acquired by the receiving unit 130.

The reflecting portion 202 is configured to reflect the probe beam collimated by the supporting portion 201 to the scanning unit 300, and the reflecting portion 202 is configured to reflect the echo beam scanned by the scanning unit 300 to the supporting portion 201.

In this embodiment, the reflecting portion 202 is configured to reflect the probe beam passing through the supporting portion 201 or to reflect the echo beam passing through the scanning unit 300.

In this embodiment, the attenuation unit 10 is located between the supporting portion 201 and the reflecting portion 202.

In this embodiment, the optical machine module 200 further includes: and an optical unit mounting portion 2015 located at a side portion of the supporting portion 201. The reflecting portion 202 has reflecting portion mounting portions 2022, and the reflecting portion mounting portions 2022 are located between the optical machine mounting portions 2015.

The reflecting portion mounting portion 2022 is located between the optical machine mounting portions 2015, which is beneficial to optimizing the spatial structure of the optical machine module 200 and improving the structural compactness of the optical machine module 200.

As shown in fig. 11, a plurality of transceiver modules 100 are arranged side by side and at intervals on a side of the supporting portion 201 facing away from the reflecting portion 202.

The probe beam and the echo beam can be optically shaped by an optical unit in the support 201.

The scanning unit 300 includes: a fixing portion 301 fixedly provided on the top of the supporting portion 201; and a galvanometer unit 302 positioned on the fixing portion 301.

In this embodiment, the fixing portion 301 is fixedly disposed on top of the supporting portion 201, so that the supporting portion 201 and the scanning unit 300 are located on the same side of the reflecting portion 202, which is beneficial for the reflecting portion 202 to reflect the probe beam and the echo beam, and transmit the probe beam and the echo beam between the supporting portion 201 and the scanning unit 300.

Specifically, the fixing portion 301 is located at the top of the top plate 2011 of the supporting portion 201, the fixing portion 301 has a through hole, the top plate 2011 has a corresponding threaded hole, and a screw penetrates through the through hole of the fixing portion 301 and is fixedly connected with the threaded hole of the top plate 2011.

The galvanometer unit 302 is configured to reflect the probe beam transmitted by the optical engine module 200 to scan the three-dimensional space, and is also configured to receive the echo beam provided by the three-dimensional space.

In this embodiment, the galvanometer unit 302 includes a galvanometer 3021 and a galvanometer bracket 3022 located at an edge of the galvanometer, where the galvanometer bracket 3022 is fixedly connected to the fixing portion 301, and the galvanometer 3021 is used to reflect the probe beam and the echo beam to pass through.

When the lidar works, a plurality of probe beams emitted by a plurality of transceiver modules 100 pass through corresponding optical channels, and after the probe beams are optically shaped by optical units in the optical channels, the probe beams are reflected by a reflecting part 202 and jointly irradiated on the center position of the vibrating mirror 3021; the echo beams corresponding to the plurality of probe beams are also irradiated on the center of the vibrating mirror 3021, reflected by the vibrating mirror 3021 and the reflecting portion 202, respectively pass through the corresponding optical channels, and are optically shaped by the optical units in the optical channels, and then are transmitted to the transceiver module 100.

The galvanometer unit 302 further includes: and an output end of the driving structure is connected with the vibrating mirror 3021, and is used for driving the vibrating mirror 3021 to periodically rotate in the horizontal and vertical directions, so as to realize scanning. Specifically, the driving structure drives the galvanometer 3021 under the action of the lorentz magnetic force to perform periodic rotational scanning.

In this embodiment, the galvanometer unit 302 is obliquely disposed on top of the fixing portion 301, so that the probe beam is reflected by the galvanometer unit 302 to the outside of the laser radar, and the echo beam is reflected by the galvanometer unit 302 to the reflecting portion 202.

Specifically, the top of the fixing portion 301 includes: the connection wall 3011 and the galvanometer unit 302 are disposed at the top of the fixing portion 301 by tilting the connection wall 3011, so that the galvanometer unit 302 faces the reflecting portion 202, for transmitting the probe beam and the echo beam between the galvanometer unit 302 and the reflecting portion 202.

Specifically, the connecting wall 3011 has a through hole, the galvanometer support 3022 has a threaded hole, and a screw penetrates through the through hole in the connecting wall 3011 and is fixedly connected with the threaded hole in the galvanometer support 3022.

The lidar further comprises: motherboard module 400.

The main board module 400 is electrically connected to the transceiver module 100, and the specific main board module 400 is electrically connected to the transmitting unit 120 and the receiving unit 130, where the main board module 400 enables the transmitting unit 120 to provide a probe beam, so as to ensure that the main board module 400 can receive an electrical signal photoelectrically converted by the receiving unit and process the signal.

In this embodiment, the motherboard module 400 includes: the lower main board module 401 is located at a side of the transceiver module 100 facing away from the optical transceiver module, and the bottom of the lower main board module 401 includes a plurality of main board mounting portions 402, where a plurality of main board mounting portions 402 and a plurality of transceiver modules 100 are staggered.

The staggered arrangement of the plurality of motherboard mounting portions 402 and the plurality of transceiver modules 100 is beneficial to fully utilizing the space structure inside the laser radar and improving the compactness of the laser radar.

The motherboard module 400 further includes: the upper motherboard module 403 is located on top of the transceiver module 100 and the scanning unit 300.

The upper and lower main board modules 403 and 401 are respectively located at the top and back of the transceiver module 100 and the scanning unit 300, which is advantageous for heat dissipation of the main board module 400 and improves the working performance of the laser radar compared with the case where the upper and lower main board modules 403 and 401 are stacked.

The laser radar further comprises; the housing 500 (as shown in fig. 10), the optical module 200, the scanning unit 300, the plurality of transceiver modules 100, and the main board module 400 are located in the housing 500, the upper main board module 403 is connected to the top of the housing 500, and the lower main board module 401 is connected to the side wall of the housing 500.

Specifically, the transceiver module 100 is positioned with the bottom of the housing 500 by a pin, a base through hole is formed in a base in the transceiver module 100, a threaded hole corresponding to the base through hole is formed in the bottom of the housing 500, and a screw penetrates through the bottom through hole to fixedly connect the transceiver module 100 with the housing 500.

As an example, the bottom through holes are scattered on the base. The bottom through holes are arranged in a scattered manner, so that the firmness degree of the combination of the transceiver module and the shell can be improved.

Specifically, the supporting portion 201 is positioned with the bottom of the housing 500 by a pin, the optical machine mounting portion 2015 is provided with a mounting portion through hole, the bottom of the housing 500 is provided with a threaded hole corresponding to the mounting portion through hole, and a screw penetrates through the mounting portion through hole to fixedly connect the supporting portion 201 with the housing 500.

Specifically, the reflecting portion 202 is positioned with the bottom of the housing 500 by a pin, the reflecting portion mounting portion 2022 of the reflecting portion 202 has a reflecting portion through hole, the bottom of the housing 500 has a threaded hole corresponding to the reflecting portion through hole, and a screw penetrates through the reflecting portion through hole to fixedly connect the reflecting portion 202 with the housing 500.

Correspondingly, in this embodiment, the lower motherboard module 401 is fixed on the side wall of the housing 500 by a screw, and the upper motherboard module 403 is fixedly connected with the top of the housing 500 by a screw.

The transceiver module 100, the optical machine module 200 and the main board module 400 in the laser radar provided by the application are fixed in the shell 500, the scanning unit 300 is fixedly connected with the supporting part 201 of the optical machine module 200, so that the scanning unit 300 and the shell 500 are relatively fixed, and the relative positions among the transceiver module 100, the optical machine module 200, the scanning unit 300 and the main board module 400 are fixed.

Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the application, and the scope of the application should be assessed accordingly to that of the appended claims.

Claims (16)

1. A lidar, comprising:

an emission unit configured to provide a probe beam, the probe beam being reflected by a target object to form an echo beam;

a receiving unit configured to receive the echo beam within a reception field of view;

an attenuation unit configured to attenuate ambient light outside the reception field of view;

and a scanning unit configured to perform spatial scanning using the probe beam and the echo beam.

2. The lidar of claim 1, wherein the attenuation unit is located upstream of the receiving unit on a transmission path of the echo beam, and is configured to absorb ambient light or deflect an ambient light transmission direction.

3. The lidar of claim 2, wherein the attenuation unit comprises: and a focal length extension unit configured to extend a focal length of the received echo beam.

4. The lidar of claim 3, wherein the lidar further comprises:

a spectroscopic device located downstream of the transmission path of the transmitting unit, configured to transmit the probe beam and irradiate the probe beam toward a target object, the spectroscopic device being further configured to reflect the echo beam to the receiving unit;

the focal length extension unit is positioned between the beam splitting device and the receiving unit on the transmission path of the echo beam.

5. The lidar of claim 2, wherein the attenuation unit comprises an ambient light reflecting structure.

6. The lidar of claim 5, wherein the ambient light reflection structure comprises a saw tooth structure.

7. The lidar of claim 6, wherein the surface of the saw tooth structure is perpendicular to the direction of ambient light transmission.

8. The lidar of claim 5, wherein the ambient light reflection structure comprises: a light absorbing layer;

and the plurality of cone-shaped reflectors are arranged on the light absorption layer at intervals and are configured to reflect the ambient light to the light absorption layer.

9. The lidar of claim 8, wherein the ambient light reflection structure further comprises: and a reflection enhancer, located between the reflectors on the light absorbing layer, configured to increase the number of times ambient light is reflected.

10. The lidar of claim 2, wherein the attenuation unit comprises a porous structure configured to absorb ambient light.

11. The lidar of any of claims 5 to 10, wherein the surface of the ambient light reflecting structure or the porous structure is subjected to at least one of electrophoresis, anodic oxidation, micro-arc or blackening treatment.

12. The lidar of claim 1, wherein the lidar further comprises:

and the optical machine unit is configured to transmit the detection light beam to the scanning unit and transmit the echo light beam to the receiving unit.

13. The lidar of claim 12, wherein the opto-mechanical unit comprises:

a support configured to transmit the probe beam and the echo beam and support the scanning unit;

a reflection section configured to reflect the probe beam to the scanning unit and reflect the echo beam to the supporting section;

the attenuation unit is positioned between the supporting part and the reflecting part.

14. The lidar of claim 13, wherein the lidar further comprises: the receiving module comprises a transmitting unit and a receiving unit;

the transceiver modules are arranged side by side and at intervals on one side of the supporting part, which is away from the reflecting part.

15. The lidar of claim 13, wherein the support portion comprises:

a plurality of optical channels arranged along transmission paths of the probe beam and the echo beam;

the optical units are correspondingly arranged in the optical channels.

16. The lidar of claim 13, wherein the scanning unit comprises:

a fixing part fixed on the top of the supporting part;

and a galvanometer unit obliquely disposed on top of the fixing part and configured to reflect the probe beam and the echo beam by the galvanometer unit.