CN217981830U

CN217981830U - Laser radar

Info

Publication number: CN217981830U
Application number: CN202222258695.6U
Authority: CN
Inventors: 周思雨; 王瑞; 张弛
Original assignee: Shenzhen North Wake Technology Co ltd
Current assignee: Shenzhen North Wake Technology Co ltd
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2022-12-06
Anticipated expiration: 2032-08-25

Abstract

An embodiment of the utility model provides a laser radar relates to the radar field. The laser radar comprises a transmitting module, a reflector group, a receiving module, a first scanning module and a second scanning module. The emission module, the reflector group, the first scanning module and the second scanning module are sequentially arranged to form a laser emission light path, and can project emitted laser formed by the emission module to a detected target object. The second scanning module, the first scanning module, the reflector group and the receiving module are sequentially arranged to form a laser receiving light path, and the laser receiving light path can project the reflected laser generated by the detected target object according to the emitted laser to the receiving module. The first scanning module and the second scanning module can rotate and scan in different directions to change the emitting directions of the emitted laser and the reflected laser. The range of the field angle of the laser radar can be increased, and meanwhile, the overall size of the laser radar can be relatively small.

Description

Laser radar

Technical Field

The utility model relates to a radar technical field particularly, relates to a laser radar.

Background

As the key device in the field of automatic driving, with the increasing development and popularization of automatic driving in recent years, higher technical requirements are also put forward on the laser radar, such as using the laser radar which needs a smaller volume above or at the front end of an automobile, and needing a larger angle of view and range for obtaining a larger detection field of view.

The technical scheme that the existing laser radar generally adopts for improving the detection field of view is that a plurality of transmitting arrays are directly used, namely at least dozens of transmitting channels are used to ensure the detection range of a vertical field of view, but the scheme can increase the whole size of the laser radar.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a laser radar, for example, its range that can increase laser radar's angle of vision also can let laser radar's whole size is less relatively simultaneously.

The embodiment of the utility model discloses a can realize like this:

in a first aspect, the present invention provides a lidar comprising a transmitting module, a mirror group, a receiving module, a first scanning module and a second scanning module;

the emission module, the reflector group, the first scanning module and the second scanning module are sequentially arranged to form a laser emission light path, and can project emitted laser formed by the emission module to a measured target object;

the second scanning module, the first scanning module, the reflector group and the receiving module are sequentially arranged to form a laser receiving light path, and the laser receiving light path can project the reflected laser generated by the detected target object according to the emitted laser to the receiving module;

the first scanning module and the second scanning module can rotate and scan in different directions so as to change the emitting directions of the emitted laser and the reflected laser.

In an alternative embodiment, the transmitting module, the mirror group, the receiving module and the first scanning module are arranged in the same horizontal direction of the lidar.

In an alternative embodiment, the set of mirrors comprises a mirror and a reflective transmissive mirror;

the reflecting mirror and the reflecting and transmitting mirror are used for changing the projection direction of the reflected laser and/or the reflected laser, so that the emitted laser formed by the emitting module is projected to the first scanning module and the reflected laser emitted by the first scanning module is projected to the receiving module.

In an alternative embodiment, the reflecting mirror and the reflective and transmissive mirror are both disposed in the laser emission optical path, and both the reflecting mirror and the reflective and transmissive mirror are configured to change a projection direction of the emitted laser light to reflect the emitted laser light formed by the emitting module to the first scanning module;

the reflection and transmission mirror is arranged in the laser receiving light path, and the reflected laser light reflected by the first scanning module can at least partially penetrate through the reflection and transmission mirror and is projected to the receiving module.

In an alternative embodiment, the transmitting module, the receiving module and the first scanning module are sequentially arranged in a first direction, the reflecting mirror and the transmitting module are sequentially arranged in a second direction, the reflective transmissive mirror and the receiving module are sequentially arranged in the second direction, and the reflecting mirror, the reflective transmissive mirror and the first scanning module are sequentially arranged in the second direction;

the first direction and the second direction are two vertical directions in the same horizontal plane;

in the laser emission optical path, the emitted laser formed by the emission module is reflected by the reflecting mirror and projected on the reflective transmission mirror, and is projected on the first scanning module through the reflective transmission mirror, and is changed in direction and reflected by the first scanning module and projected on the second scanning module, and then is changed in direction by the second scanning module and projected on the measured target object;

in the laser receiving optical path, the target object to be detected received by the second scanning module is reflected to the first scanning module according to the reflected laser generated by the emitted laser, is emitted and projected to the reflective transmission mirror through the first scanning module, and is projected to the receiving module through the reflective transmission mirror.

In an optional embodiment, the reflective and transmissive mirror is disposed in the laser emission optical path, and the emitted laser light emitted by the emission module at least partially penetrates through the reflective and transmissive mirror, and is projected to the first scanning module, reflected by the first scanning module, projected to the second scanning module, and projected to the target object to be measured by the second scanning module;

the reflecting mirror and the reflecting and transmitting mirror are arranged in the laser receiving light path and are used for changing the projection direction of the reflected laser so as to reflect the reflected laser generated by the detected target object according to the emitted laser to the receiving module.

In an alternative embodiment, the receiving module, the emitting module, and the first scanning module are sequentially arranged in a first direction, the reflecting mirror and the receiving module are sequentially arranged in a second direction, the reflective transmissive mirror and the emitting module are sequentially arranged in the second direction, and the reflecting mirror, the reflective transmissive mirror, and the first scanning module are sequentially arranged in the second direction;

in the laser emission optical path, at least part of the emitted laser formed by the emission module is projected on the first scanning module through the reflective transmission mirror, changes the direction through the first scanning module, is reflected to be projected to the second scanning module, and then changes the direction through the second scanning module to be projected to the measured target object;

in the laser receiving optical path, the target object to be detected received by the second scanning module is reflected to the first scanning module according to the reflected laser generated by the emitted laser, is emitted and projected to the reflective and transmissive mirror through the first scanning module, is reflected and projected to the reflecting mirror through the reflective and transmissive mirror, and is reflected to the receiving module through the reflecting mirror.

In an alternative embodiment, the centers of the emitting module, the mirror group, the receiving module and the first scanning module are all located at the same height.

In an alternative embodiment, the lidar further comprises a transmit lens and a receive lens;

the emission lens is arranged on the laser emission light path and is positioned on one side of the emission module, from which the emitted laser is emitted;

the receiving lens is arranged on the laser receiving light path and is positioned on one side of the receiving module, where the reflected laser light is incident.

In an alternative embodiment, the first scanning module may be rotatable in a height direction of the lidar and the second scanning module may be rotatable in a direction perpendicular to the height direction of the lidar.

In an alternative embodiment, the first scanning module has a rotation axis along which the first scanning module is rotatable in the direction of the height of the lidar, the rotation axis being at an angle of 42.5 ° to the second direction.

In an alternative embodiment, the second scanning module comprises a prism having a square cross section, and the prism is rotatable to change the emitting directions of the emitted laser light and the reflected laser light.

In an alternative embodiment, four corners in the height direction of the prism are provided with chamfers.

In an alternative embodiment, the four corners of the prism in the height direction are all chamfered by C3.

The embodiment of the utility model provides a laser radar's beneficial effect includes:

this application is through setting up first scanning module and second scanning module in laser emission light path and laser receiving light path to let first scanning module and second scanning module rotate at two differences, and utilize the reflection of laser between first scanning module and second scanning module, thereby can make laser radar's angle of view and range increase, thereby can reduce emission module's volume and reduce passageway quantity.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on these drawings without inventive efforts.

Fig. 1 is a schematic view of a top view arrangement of a laser radar according to an embodiment of the present invention;

fig. 2 is a schematic top view arrangement diagram of a laser radar according to another embodiment of the present invention;

fig. 3 is a schematic view of a top-view arrangement of a laser radar according to another embodiment of the present invention.

Icon: 100-laser radar; 110-a transmitting module; 120-an emission lens; 130-a mirror group; 131-a mirror; 133-reflective transmissive mirror; 140-a receiving lens; 150-a receiving module; 170-a first scanning module; 171-axis of rotation; 190-a second scanning module; 191-chamfering.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the accompanying drawings, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without making creative efforts belong to the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that, if the terms "upper", "lower", "inner", "outer", etc. indicate the position or positional relationship based on the position or positional relationship shown in the drawings, or the position or positional relationship which is usually placed when the products of the present invention are used, the description is only for convenience of description and simplification, but the indication or suggestion that the indicated device or element must have a specific position, be constructed and operated in a specific orientation, and thus, should not be interpreted as a limitation of the present invention.

Furthermore, the appearances of the terms "first," "second," and the like, if any, are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

It should be noted that the features of the embodiments of the present invention may be combined with each other without conflict.

Referring to fig. 1 and fig. 2, an embodiment of the present invention provides a laser radar 100, where the laser radar 100 may be used for detecting obstacles in an automobile, so as to implement a self-driving function of the automobile.

In the present embodiment, the lidar 100 includes a transmitting module 110, a mirror group 130, a receiving module 150, a first scanning module 170, and a second scanning module 190. The emission module 110, the mirror assembly 130, the first scanning module 170 and the second scanning module 190 are sequentially disposed to form a laser emission optical path, which can project the emitted laser formed by the emission module 110 to the target object to be measured. The second scanning module 190, the first scanning module 170, the mirror assembly 130, and the receiving module 150 are sequentially disposed to form a laser receiving optical path, which can project the reflected laser generated by the detected target object according to the emitted laser to the receiving module 150. The first and

second scanning modules

170 and 190 may rotate to scan in different directions to change the emission directions of the emitted and reflected laser lights.

In the embodiment, the first scanning module 170 and the second scanning module 190 are disposed in the laser emitting light path and the laser receiving light path, the first scanning module 170 and the second scanning module 190 rotate in two different directions, and the reflection of the laser light between the first scanning module 170 and the second scanning module 190 is utilized, so that the field angle and the range of the laser radar 100 can be increased, and the volume of the emitting module 110 and the number of channels can be reduced.

Referring to fig. 1 and 2, in the present embodiment, the transmitting module 110, the mirror assembly 130, the receiving module 150 and the first scanning module 170 are arranged in the same horizontal direction of the laser radar 100.

In the present embodiment, the transmitting module 110, the reflecting mirror assembly 130, the receiving module 150 and the first scanning module 170 are arranged on a horizontal plane, so that the height of the lidar 100 can be reduced, which is more beneficial for the lidar 100 to be mounted on a vehicle.

In the present embodiment, the mirror group 130 includes a mirror 131 and a reflective and transmissive mirror 133. The reflective mirror 131 and the reflective/transmissive mirror 133 are used to change the projection direction of the reflected laser light and/or the reflected laser light, so that the emitted laser light formed by the emitting module 110 is projected to the first scanning module 170 and the reflected laser light emitted by the first scanning module 170 is projected to the receiving module 150.

In this embodiment, the reflection/transmission mirror 133 may use the principle that the reflection/projection mirror can reflect and project laser light, so as to simultaneously realize the projection of the emitted laser light and the reflection of the received laser light, thereby avoiding the interference between the laser emission optical path and the laser reception optical path.

Referring to fig. 1, in the present embodiment, the reflective mirror 131 and the reflective transmissive mirror 133 are both disposed in the laser emission light path, and the reflective mirror 131 and the reflective transmissive mirror 133 are both used for changing the projection direction of the emitted laser to reflect the emitted laser formed by the emission module 110 to the first scanning module 170. The reflective and transmissive mirror 133 is disposed in the laser receiving optical path, and the reflected laser light reflected by the first scanning module 170 can at least partially transmit through the reflective and transmissive mirror 133 and be projected to the receiving module 150. The emission module 110, the reception module 150, and the first scanning module 170 are sequentially arranged in a first direction, the reflection mirror 131 and the emission module 110 are sequentially arranged in a second direction, the reflection transmission mirror 133 and the reception module 150 are sequentially arranged in the second direction, and the reflection mirror 131, the reflection transmission mirror 133, and the first scanning module 170 are sequentially arranged in the second direction. The first direction and the second direction are two vertical directions in the same horizontal plane. In the laser emitting optical path, the emitted laser formed by the emitting module 110 is reflected by the reflecting mirror 131 and projected on the reflective and transmissive mirror 133, and is projected on the first scanning module 170 through the reflective and transmissive mirror 133, and is changed in direction and reflected by the first scanning module 170 and projected on the second scanning module 190, and then is changed in direction and projected on the measured target object through the second scanning module 190. In the laser receiving optical path, the target object to be measured received by the second scanning module 190 is reflected to the first scanning module 170 according to the reflected laser generated by the emitted laser, is emitted and projected to the reflective and transmissive mirror 133 through the first scanning module 170, and is projected to the receiving module 150 through the reflective and transmissive mirror 133.

Referring to fig. 1, in the present embodiment, the laser radar 100 further includes a transmitting lens 120 and a receiving lens 140, where the transmitting lens is further included in the laser radar 100. The emission lens 120 is disposed on the laser emission optical path, and the emission lens 120 is located at a side of the emission module 110 from which the emitted laser light exits. The receiving lens 140 is disposed on the laser receiving optical path, and the receiving lens 140 is located on the side of the receiving module 150 where the reflected laser is incident.

In the present embodiment, the centers of the emitting module 110, the mirror group 130, the receiving module 150, the first scanning module 170, the emitting lens 120 and the receiving lens 140 are all located at the same height.

Referring to FIG. 1, the present embodimentIn the example, the reflecting mirror 131 and the reflecting and transmitting mirror 133 are parallel and inclined with respect to the horizontal plane, and the included angle between the reflecting mirror 131 and the horizontal plane is 45 °, that is, the length of the reflecting mirror 131 is at least the size of the emission light spot

And (4) doubling. The emission module 110, the emission lens 120, and the reflection mirror 131 should be arranged in consideration of the movement traces of the first scanning module 170 and the second scanning module 190, so as not to interfere therewith.

It should be noted that, because the distance between the emission module 110 and the emission lens 120 is related to the focal length of the lens assembly, the size of the reflector 131 can completely cover the size of the collimated light spot of the emission lens 120, it is assumed that the transverse size of the collimated light spot of the emission lens 120 is X (it should be noted that the transverse size of the collimated light spot X represents the side length or the diameter of the light spot, for example, when the collimated light spot is circular, the transverse size X of the collimated light spot is the diameter of the light spot, if the collimated light spot is rectangular, the transverse size of the collimated light spot refers to the transverse side length of the rectangle), the inclination angle between the reflector 131 and the horizontal plane is a, the minimum length of the reflector 131 is X/cosa, in the utility model, a is 45 °, that the length of the reflector 131 is at least the size of the emission light spot, i.e., the length of the reflector 131 is at least the size of the emission spot

Doubling; in principle, the closer the distance between the emitting lens 120 and the reflector 131 should be, the better, but in the actual layout design, the size of the lens module should be considered, and the distance should be reduced as much as possible without interfering with the reflector 131. The center of the reflective-transmissive device coincides with the center of the mirror 131 in the same vertical direction.

In this embodiment, the reflective/transmissive mirror 133 is a half-reflective/half-transmissive mirror, and allows one of the emitted laser light and the reflected laser light to transmit therethrough and the other to reflect. Therefore, the reflective/transmissive mirror 133 may be formed by plating a transmissive film in a region adjacent to the reflective film in the middle of one mirror 131, or may be formed by using only one mirror 131 having a small area.

Referring to fig. 1, in the present embodiment, the first scanning module 170 can rotate in a height direction of the laser radar 100, and the second scanning module 190 can rotate in a direction perpendicular to the height direction of the laser radar 100.

In this embodiment, the first scanning module 170 is configured to rotate to scan the emitted laser reflected by the reflective/transmissive mirror 133, so that the emitted laser meets the requirement of a vertical field angle, and the first scanning module 170 may have a mirror driven by a motor or an electromagnetic device to perform a tilting motion. The second scanning module 190 is used for rotating scanning in a horizontal plane to make the emitted laser received by the first scanning module 170 reach a requirement of a horizontal field angle. The second scanning module 190 may be a two-sided, three-sided, or four-sided polygon prism. The second scanning module 190 is a triangular prism in this embodiment. The receiving lens 140, which may be a single lens or a lens group, is used for converging the emitted laser light.

The advantage of the above layout is that if the length of the transmitting part is made longer, the transmitting part needs to be bent to be in an L shape, so that the whole structure is more convenient to arrange, and the transmitting part is not easy to generate structural interference with the receiving part module.

Referring to fig. 2, in some other embodiments of the present disclosure, the reflective transmissive mirror 133 is disposed in the laser emission path, and at least a portion of the emitted laser light emitted by the emission module 110 passes through the reflective transmissive mirror 133, and is projected to the first scanning module 170, reflected by the first scanning module 170, projected to the second scanning module 190, and projected to the target object to be measured by the second scanning module 190. The reflecting mirror 131 and the reflecting and transmitting mirror 133 are both disposed in the laser receiving light path, and the reflecting mirror 131 and the reflecting and transmitting mirror 133 are both configured to change the projection direction of the reflected laser, so as to reflect the reflected laser generated by the detected target object according to the emitted laser to the receiving module 150. The receiving module 150, the emitting module 110, and the first scanning module 170 are sequentially arranged in a first direction, the reflecting mirror 131 and the receiving module 150 are sequentially arranged in a second direction, the reflective transmissive mirror 133 and the emitting module 110 are sequentially arranged in the second direction, and the reflecting mirror 131, the reflective transmissive mirror 133, and the first scanning module 170 are sequentially arranged in the second direction. The first direction and the second direction are two vertical directions in the same horizontal plane. In the laser emitting optical path, at least a part of the emitted laser formed by the emitting module 110 is projected onto the first scanning module 170 through the reflective and transmissive mirror 133, is changed in direction by the first scanning module 170, is reflected and projected onto the second scanning module 190, and is then changed in direction by the second scanning module 190 and projected onto the target object to be measured. In the laser receiving optical path, the target object to be measured received by the second scanning module 190 is reflected to the first scanning module 170 according to the reflected laser generated by the emitted laser, is emitted and projected to the reflective and transmissive mirror 133 through the first scanning module 170, is reflected and projected to the reflective mirror 131 through the reflective and transmissive mirror 133, and is then reflected to the receiving module 150 through the reflective mirror 131.

In the layout of fig. 2, since the emitting module 110 is placed in front of the receiving module 150 in the first direction, the reflection of the emitted laser light by the reflective projection mirror 133 can be reduced, thereby reducing stray light. If the transmission module 110 is disposed behind the reception module 150, part of the emitted light of the transmission module 110 is directly incident into the reception module 150 through the perforated mirror 131.

Referring to fig. 3, in some other embodiments of the present application, fig. 3 is substantially the same as fig. 1, except that the first scanning module 170 has a rotation axis 171, the first scanning module 170 is rotatable along the rotation axis 171 in the height direction of the lidar 100, and the angle between the rotation axis 171 and the second direction is 42.5 °. The second scanning module 190 includes a prism and a driving motor, and the driving motor is in transmission connection with the prism. The cross section of the prism is square, and the driving motor can drive the prism to rotate in a horizontal plane so as to change the emitting directions of the emitted laser and the reflected laser. The chamfers 191 at the four corners in the prism height direction are all C3 chamfers 191.

In this embodiment, the first scanning module 170 is set to have an angle of 42.5 ° with the second direction, so that the size of the prism of the second scanning module 190 can be reduced, thereby reducing the power consumption of the driving motor of the second scanning module 190. By providing the C3 chamfers 191 at the four corners in the height direction of the prism, the wind resistance can be reduced while satisfying the angle of view of the laser radar 100, and the power consumption of the driving motor can be reduced.

For example: the field angle of the laser radar 100 is ± 60 ° and 120 ° in total, when the angle between the first scanning module 170 and the second direction is 45 °, the zero position of the second scanning module 190 is 45 °, when the field angle requires +60 °, the second scanning module 190 needs to rotate clockwise by 30 °, at this time, the angle between the second scanning module 190 and the horizontal direction is 15 °, if the lateral size of the collimated spot is X, the length of the first scanning module 170 is X/cos45 °, and the minimum length L1 of the side of the second scanning module 190 is X/cos45 ° sin45 °/sin15 °, that is, X/sin15 °. When the angle between the first scanning module 170 and the horizontal plane is 42.5 °, the length of the first scanning module 170 is 42.5 ° X/cos, and the emitted light is actually rotated by 5 ° due to the 2.5 ° rotation of the first scanning module 170. Therefore, the null position of the second scan module 190 is 42.5 °, when the field angle requires +60 °, the second scan module 190 needs to rotate clockwise by 30 °, at this time, the angle between the second scan module 190 and the horizontal direction is 12.5 °, and if the lateral size of the collimated spot is X, the length L2 of the second scan module 190 is at least 42.5 ° X/cos sin47.5 °/sin17.5 °, i.e., X/sin17.5 °. It can be seen that L2 < L1, setting the angle between the first scanning module 170 and the second direction to 42.5 ° allows the second scanning module 190 to be reduced in size.

It should be noted that the rotation axis 171 of the first scanning module 170 refers to an axis of rotation of the first scanning module 170 in a vertical plane, and an included angle between the rotation axis 171 of the first scanning module 170 and the second direction is 42.5 ° in any angle. The C3 chamfer refers to a chamfer of 3 × 45 °.

Of course, in another embodiment of the present application, the angle between the rotation axis 171 of the first scanning module 170 and the second direction may be less than or equal to 45 °, for example, 45 °, 40 °, and the like. To sum up, the embodiment of the present invention provides a laser radar 100, whose working principle and beneficial effect include:

in the present embodiment, the first scanning module 170 and the second scanning module 190 are disposed in the laser emitting light path and the laser receiving light path, the first scanning module 170 and the second scanning module 190 are rotated in two different directions, and the reflection of the laser light between the first scanning module 170 and the second scanning module 190 is utilized, so that the field angle and the range of the laser radar 100 can be increased, the volume of the emitting module 110 can be reduced, and the number of channels can be reduced. Arranging the transmitting module 110, the mirror group 130, the receiving module 150 and the first scanning module 170 on a horizontal plane allows the height of the lidar 100 to be reduced, which is more advantageous for the lidar 100 to be mounted on a vehicle.

The above embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A laser radar is characterized by comprising a transmitting module, a reflector group, a receiving module, a first scanning module and a second scanning module;

2. The lidar of claim 1, wherein the transmitting module, the mirror group, the receiving module, and the first scanning module are arranged in a same horizontal direction of the lidar.

3. The lidar of claim 2, wherein the set of mirrors comprises a mirror and a reflective transmissive mirror;

the reflecting mirror and the reflecting transmission mirror are used for changing the projection direction of the reflected laser and/or the reflected laser, so that the emitted laser formed by the emitting module is projected to the first scanning module and the reflected laser emitted by the first scanning module is projected to the receiving module.

4. The lidar of claim 3, wherein the reflecting mirror and the reflective-transmissive mirror are both disposed in the laser emission optical path, and are each configured to change a projection direction of the emitted laser light to reflect the emitted laser light formed by the emission module to the first scanning module;

5. The lidar of claim 4, wherein said transmitting module, said receiving module, and said first scanning module are sequentially arranged in a first direction, said reflecting mirror and said transmitting module are sequentially arranged in a second direction, said reflecting transmissive mirror and said receiving module are sequentially arranged in a second direction, and said reflecting mirror, said reflecting transmissive mirror, and said first scanning module are sequentially arranged in a second direction;

in the laser receiving optical path, the target object to be detected received by the second scanning module is reflected to the first scanning module according to the reflected laser generated by the emitted laser, is emitted and projected to the reflective and transmissive mirror through the first scanning module, and is projected to the receiving module through the reflective and transmissive mirror.

6. The lidar of claim 3, wherein the reflective-transmissive mirror is disposed in the laser emission optical path, and the emitted laser emitted by the emission module at least partially penetrates through the reflective-transmissive mirror, is projected to the first scanning module, is reflected by the first scanning module, is projected to the second scanning module, and is projected to the target object to be measured by the second scanning module;

the reflector and the reflection transmission mirror are arranged in the laser receiving light path and are used for changing the projection direction of the reflected laser so as to reflect the reflected laser generated by the detected target object according to the emitted laser to the receiving module.

7. The lidar of claim 6, wherein the receiving module, the transmitting module, and the first scanning module are sequentially arranged in a first direction, the reflecting mirror and the receiving module are sequentially arranged in a second direction, the reflecting and transmitting mirror and the transmitting module are sequentially arranged in a second direction, and the reflecting mirror, the reflecting and transmitting mirror, and the first scanning module are sequentially arranged in a second direction;

8. The lidar according to any of claims 1-7, wherein centers of said transmitting module, said set of mirrors, said receiving module, and said first scanning module are all located at a same height.

9. The lidar of any of claims 1-7, wherein the lidar further comprises a transmit lens and a receive lens;

the receiving lens is arranged on the laser receiving light path and is positioned on one incident side of the reflected laser of the receiving module.

10. The lidar of any of claims 1-7, wherein the first scanning module is rotatable in a direction of a height of the lidar and the second scanning module is rotatable in a direction perpendicular to the direction of the height of the lidar.

11. The lidar of claim 5 or 7, wherein the first scanning module has an axis of rotation along which the first scanning module is rotatable in a height direction of the lidar, the axis of rotation being at an angle of 42.5 ° to the second direction.

12. The lidar of any of claims 1-7, wherein the second scanning module comprises a prism having a square cross-section that is rotatable to change the exit direction of the emitted laser light and the reflected laser light.

13. The lidar according to claim 12, wherein four corners in a height direction of the prism are provided with chamfers.

14. The lidar of claim 13, wherein the four corners in the height direction of the prism are each chamfered by a C3 chamfer.