LiDAR and devices including LiDAR

Abstract

A lidar and a device including the lidar are disclosed, comprising: a housing, a scanning component, a transmitting module, and a receiving module. The housing has an optical window. The scanning component, transmitting module, and receiving module are all located inside the housing. The scanning component is adapted to reflect the emitted light from the transmitting module onto a target object outside the optical window. The reflected light from the target object passes through the optical window and is then reflected by the scanning component to the receiving module. The scanning component is adapted to rotate relative to the optical window. The scanning component includes a first reflecting mirror and at least one second reflecting mirror that rotate synchronously. The first reflecting mirror and the second reflecting mirror are spaced apart. The first reflecting mirror has a first reflecting surface, and the second reflecting mirror has a second reflecting surface. When both the first and second reflecting surfaces face the optical window, the second reflecting surface is located between the optical window and the first reflecting mirror to improve the receiving efficiency of the lidar's edge field of view and achieve miniaturization.

Description

Technical Field

[0001] This application relates to the field of optical technology, and in particular to a lidar and a device including a lidar. Background Technology

[0002] In modern autonomous driving and intelligent transportation systems, LiDAR, as a key sensor, directly impacts the system's reliability and safety through its performance and design. However, existing semi-solid-state main-view LiDAR systems face numerous technical challenges in their pursuit of miniaturization and thinner designs.

[0003] Semi-solid-state main-view LiDARs with coaxial or off-axis transceiver modules typically rely on multi-faceted rotating mirrors or tilting mirrors to achieve scanning functionality. To meet miniaturization requirements, this design often necessitates a relatively small optical window. However, this design suffers from varying degrees of reception efficiency loss, and in some cases, no light is received at all.

[0004] Therefore, the market needs a semi-solid-state lidar solution that simultaneously meets the requirements of small size, good edge field of view ranging performance, and prevention of stray light obstruction. Summary of the Invention

[0005] One objective of this application is to improve the reception efficiency of the edge field of view perpendicular to the rotation direction of the scanning component.

[0006] Another objective of this application is to reduce the volume of the optical region of a lidar.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows: a lidar, comprising: a housing, a scanning component, a transmitting module, and a receiving module. The housing has an optical window. The scanning component, the transmitting module, and the receiving module are all located inside the housing. The scanning component is adapted to reflect the emitted light from the transmitting module onto a target object outside the optical window. The reflected light from the target object passes through the optical window and is then reflected by the scanning component to the receiving module. The scanning component is adapted to rotate relative to the optical window. The scanning component includes a synchronously rotating first reflector and at least one second reflector. The first reflector and the second reflector are spaced apart. The first reflector has a first reflecting surface, and the second reflector has a second reflecting surface. When both the first reflecting surface and the second reflecting surface face the optical window, the second reflecting surface is located between the optical window and the first reflector.

[0008] Preferably, the number of the second reflectors is greater than or equal to the number of the first reflectors.

[0009] As a preferred embodiment, the second reflector is located near the edge of the first reflector.

[0010] As a preferred embodiment, the scanning component has a rotating axis, the first reflector and the second reflector rotate around the rotating axis, a plane is perpendicular to the rotating axis, the projection of the first reflector onto the plane is a first projection, the projection of the second reflector onto the plane is a second projection, and the distance between the rotating axis and the first projection is less than the distance between the rotating axis and the second projection.

[0011] As a preferred embodiment, the second reflecting surface and the first reflecting surface are projected onto a plane perpendicular to the axis of rotation, and the axis of rotation and the second projection do not intersect.

[0012] As a preferred embodiment, the rotating axis does not intersect with the first projection.

[0013] As a preferred embodiment, on a plane perpendicular to the rotation axis, the projections of the optical axis of the transmitting module and the optical axis of the receiving module onto the first plane are straight lines, and the projections of the transmitting module and the receiving module onto the first plane are located on the same side of the scanning component.

[0014] As a preferred embodiment, the first projection and the second projection are two parallel lines, and the length of the first projection is greater than the length of the second projection.

[0015] As a preferred embodiment, the vertical projection point of the geometric center of the second reflective surface onto the first reflective surface is A1, and the distance between A1 and the edge of the first reflective surface is L1, where L1 = β = π / 4 - α / 4;

[0016] Where d is the vertical distance between the second reflective surface and the first reflective surface, D is the diameter of the emitted light spot from the laser radar's transmitting module, α is the field of view angle of the laser radar in the plane, and L is the length of the second reflective surface in the plane.

[0017] As a preferred option, 60°≤α≤150°.

[0018] As a preferred option, 0 < L ≤ β = π / 4 - α / 4, where d is the vertical distance between the second reflecting surface and the first reflecting surface, D is the diameter of the emitted light spot of the laser radar's transmitting module, α is the field of view of the laser radar in the plane, and L is the length of the second reflecting surface in the plane.

[0019] As a preferred option, β = π / 4 - α / 4, where d is the vertical distance between the second reflecting surface and the first reflecting surface, D is the diameter of the emitted light spot from the laser radar's transmitting module, and α is the field of view angle of the laser radar in the plane.

[0020] As a preferred embodiment, when the first reflective surface and the second reflective surface face the optical window, the rotating axis is located on the side of the first reflective surface away from the second reflective surface, and within the plane, the projection of the rotating axis, the midpoint of the first projection, and the midpoint of the second projection are not collinear.

[0021] As a preferred embodiment, the scanning assembly has a rotating axis about which the first and second reflectors rotate, and the rotating axis is parallel to the first and / or the second reflective surface.

[0022] As a preferred embodiment, the lidar includes at least one of the scanning components. The emitted light is emitted outside the optical window via the first reflective surface and / or the second reflective surface. After being reflected by the external object being detected, the reflected light is formed. The reflected light passes through the optical window and is reflected by the first reflective surface and / or the second reflective surface to be collected by the receiving module.

[0023] As a preferred embodiment, when both the first reflective surface and the second reflective surface face the receiving module, the second reflective surface is located between the first reflective surface and the receiving module.

[0024] As a preferred embodiment, it also includes a reflection module disposed on the light emission path of the emission module for reflecting the emitted light to the scanning component; or,

[0025] It is positioned on the path of the receiving module to reflect the reflected light back to the receiving module for collection by the receiving module.

[0026] As a preferred embodiment, the transmitting module and the receiving module are arranged off-axis on the same side, and the main ray of the emitted light reaching the scanning component is parallel to the main ray of the reflected light after being reflected by the scanning component.

[0027] As a preferred embodiment, the off-axis distance of the transmitting module and the receiving module is N, where 0 < N < (R1 + R2) / 2, where R1 is the mechanical diameter of the transmitting module and R2 is the mechanical diameter of the receiving module.

[0028] Preferably, the second reflective surface is located on the side of the first reflective surface closer to the receiving module, and the scanning component has at least two of the following operating states:

[0029] In the first working state, the scanning component rotates. When detecting the negative edge field of view, the emitted light is emitted from the emitting module, reflected by the first reflecting surface out of the optical window, and the reflected light is recovered by the second reflecting surface to the receiving module.

[0030] In the second working state, as the scanning component rotates and the lidar detection area shifts from the negative edge of the field of view to the center of the field of view, the emitted light is emitted from the emitting module, reflected by the first and second reflecting surfaces and exits the optical window, and the reflected light is recovered by the first and second reflecting surfaces and returned to the receiving module.

[0031] In the third working state, when the scanning component rotates and the lidar detection area is the central field of view, the emitted light is emitted from the transmitting module, reflected by the first and second reflecting surfaces and exits the optical window, and the reflected light is recovered by the first reflecting surface to the receiving module.

[0032] In the fourth working state, as the scanning component rotates and the lidar detection area shifts from the central field of view to the positive edge field of view, the emitted light is emitted from the emitting module, reflected by the first and second reflecting surfaces, and exits the optical window. The reflected light is then recovered by the first reflecting surface and returned to the receiving module.

[0033] In operating state five, when the scanning component rotates and the lidar detection area is at the positive edge of the field of view, the emitted light is emitted from the emitting module, reflected by the first reflective surface out of the optical window, and the reflected light is recovered by the first reflective surface to the receiving module.

[0034] Compared with the prior art, the beneficial effects of this application are as follows:

[0035] (1) Without changing the overall height of the machine, the scanning space occupied by the transceiver module and the scanning component, the scanning component architecture in this application can be used to reduce the optical path from the front surface of the receiving module to the optical window by utilizing the second reflective surface, thereby improving the receiving efficiency of the edge field of view perpendicular to the rotation surface of the scanning component.

[0036] (2) The lidar of this application can reduce the space required for the reflected light to enter the receiving module by utilizing the second reflective surface, thereby reducing the size of the optical space in the lidar and enabling the lidar to be miniaturized. Attached Figure Description

[0037] Figure 1A This is a schematic diagram of the XY plane structure of a lidar in one embodiment of this application.

[0038] Figure 1BThis is a schematic diagram of the field of view angle of a lidar in one embodiment of this application.

[0039] Figure 2A This is a three-dimensional structural diagram of a lidar in one embodiment of this application.

[0040] Figure 2B This is a three-dimensional structural diagram of a lidar with shortened backlight in one embodiment of this application.

[0041] Figure 3 This is a schematic diagram of the XY plane structure of a lidar in the prior art.

[0042] Figure 4 This is a schematic diagram of the XY plane structure in one embodiment of this application, showing the transmitting module and the receiving module arranged in parallel.

[0043] Figure 5 This is a schematic diagram of the XY plane structure in another embodiment of this application, showing the transmitting module and the receiving module arranged in parallel.

[0044] Figure 6 This is a schematic diagram of the XY plane structure of the dual scanning component in one embodiment of this application.

[0045] Figure 7 This is a schematic diagram of a scanning component having two second reflective surfaces in one embodiment of this application.

[0046] Figure 8 This is a schematic diagram of a scanning component having two second reflective surfaces in another embodiment of this application.

[0047] Figure 9A This is a schematic diagram of the light propagation path in a horizontal -60° field of view in one embodiment of this application.

[0048] Figure 9B This is a diagram showing the light receiving efficiency results with a second reflector in a horizontal -60° field of view according to one embodiment of this application.

[0049] Figure 9C This is a diagram showing the light receiving efficiency results in the existing technology for a horizontal -60° field of view without a second reflector.

[0050] Figure 10A This is a schematic diagram of the light propagation path in a horizontal -40° field of view in one embodiment of this application.

[0051] Figure 10B This is a diagram showing the light receiving efficiency results with a second reflector in a horizontal -40° field of view according to one embodiment of this application.

[0052] Figure 10CThis is a diagram showing the light receiving efficiency results in the existing technology for a horizontal -40° field of view without a second reflector.

[0053] Figure 11A This is a schematic diagram of the light propagation path in a horizontal -30° field of view in one embodiment of this application.

[0054] Figure 11B This is a diagram showing the light receiving efficiency results with a second reflector in a horizontal -30° field of view according to one embodiment of this application.

[0055] Figure 11C This is a diagram showing the light receiving efficiency results in the existing technology for a horizontal -30° field of view without a second reflector.

[0056] Figure 12A This is a schematic diagram of the light propagation path in a horizontal 0° field of view in one embodiment of this application.

[0057] Figure 12B This is a diagram showing the light receiving efficiency results with a second reflector in a horizontal 0° field of view according to one embodiment of this application.

[0058] Figure 12C This is a diagram showing the light receiving efficiency results for a horizontal 0° field of view without a second reflector in the prior art.

[0059] Figure 13 This is a schematic diagram of the light propagation path in a horizontal +30° field of view in one embodiment of this application.

[0060] Figure 14 This is a schematic diagram of the light propagation path in a horizontal +60° field of view in one embodiment of this application.

[0061] Figure 15 This is a schematic diagram of an XY plane structure with a horizontal field of view of 100° in one embodiment of this application.

[0062] Figure 16 This is a schematic diagram of an XY plane structure with a horizontal field of view of 110° in one embodiment of this application.

[0063] Figure 17 This is a schematic diagram illustrating the principle of existing light receiving technology.

[0064] Figure 18 This is a schematic diagram illustrating the principle of light reception in an embodiment of this application.

[0065] In the diagram: 1. Transmitting module; 2. Receiving module; 3. Scanning component; 31. First reflector; 32. Second reflector; 301. First reflecting surface; 302. Second reflecting surface; 4. Reflecting module; 5. Optical window; 6. Rotating axis; 7. Housing; 8. Normal; 9. Horizontal line; 10. Retroreflected light; 20. Optical axis; 21. First optical axis; 22. Second optical axis; 40. Principal ray; 41. First principal ray; 42. Second principal ray; 1a. Transmitter; 2a. Receiver; 3a. Scanner; 4a. Reflector; 5a. Observation window; 6a. Housing. Detailed Implementation

[0066] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0067] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.

[0068] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0069] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0070] The accompanying drawings of this application show a schematic planar diagram formed by the X and Y axes. The X, Y, and Z directions are defined in this application only for ease of understanding and are not intended to impose specific limitations. The X direction in this application may also be referred to as the first direction, the Z direction as the second direction, and the Y direction as the third direction. Any two of the first, second, and third directions are perpendicular to each other.

[0071] The optical axis 20 mentioned in this application refers to the central axis of the transmitting module 1 or the receiving module 2, and the main ray 40 refers to the ray with the strongest energy or the most central ray among the rays emitted or incident from the transmitting module 1 or the receiving module 2.

[0072] like Figure 1A , Figure 1B and Figure 2A This application provides a lidar system, including a housing 7 (not shown), a scanning component 3, a transmitting module 1, and a receiving module 2. The housing 7 has an optical window 5. The scanning component 3, the transmitting module 1, and the receiving module 2 are all located inside the housing 7. The scanning component 3 is adapted to reflect the emitted light from the transmitting module 1 onto the object being detected outside the optical window 5. The reflected light 10 formed by the object being detected passes through the optical window 5 and is then reflected by the scanning component 3 to the receiving module 2. The scanning component 3 is adapted to emit light relative to the optical window 5. The scanning assembly 3 includes a first reflecting mirror 31 and at least one second reflecting mirror 32 that rotate synchronously. The first reflecting mirror 31 and the second reflecting mirror 32 are arranged at intervals. The first reflecting mirror 31 has a first reflecting surface 301, and the second reflecting mirror 32 has a second reflecting surface 302. When both the first reflecting surface 301 and the second reflecting surface 302 face the optical window 5, the second reflecting surface 302 is located between the optical window 5 and the first reflecting mirror 31. The number of second reflecting mirrors 32 is greater than or equal to the number of first reflecting mirrors 31, and the second reflecting mirrors 32 are arranged close to the edge of the first reflecting mirror 31.

[0073] like Figure 2B As shown, it should be understood that by using at least one second reflector 32, the optical path of the reflected light 10 from the optical window 5 to the front surface of the receiving module 2 can be shortened. That is, the optical path of the reflected beam from the optical window 5 to the scanning component 3 in conventional technology is shortened, which can improve the detection and reception efficiency of the edge of the vertical field of view (Z direction) of the lidar, thereby improving the vertical field of view of the lidar. In addition, the second reflector 32 of this application can also reduce the space required for the reflected light 10 to enter the receiving module 2, thereby reducing the size of the optical space in the lidar and enabling the lidar to be miniaturized.

[0074] In some embodiments, such as Figure 2AThe scanning component 3 has a rotating shaft 6. The first reflector 31 and the second reflector 32 rotate around the rotating shaft 6. The first plane (i.e. the plane formed by the XY axes) is perpendicular to the rotating shaft 6. The projection of the first reflector 301 on the first plane is the first projection, and the projection of the second reflector 302 on the first plane is the second projection. The distance between the rotating shaft 6 and the first projection is less than the distance between the rotating shaft 6 and the second projection. That is, the second reflector 302 is located on the side away from the rotating shaft 6 and the first reflector 301, thereby ensuring that the second reflector 302 is positioned between the first reflector 301 and the optical window 5, thus reducing the optical path from the front end of the receiving module 2 to the optical window 5.

[0075] In some embodiments, the second reflective surface 302 and the first reflective surface 301 are projected onto a plane perpendicular to the rotating axis 6, and the rotating axis 6 has no intersection with the second projection, which can effectively avoid the rotating axis 6 from blocking the light path during rotation.

[0076] In some embodiments, the second reflective surface 302 and the first reflective surface 301 are projected onto a plane perpendicular to the rotation axis 6. The rotation axis 6 and the first projection have no intersection, so the rotation axis 6 will not directly block or interfere with the first reflective surface 301 in the optical path, thus avoiding light loss. At this time, the second reflective surface 302 is disposed between the first reflective surface 301 and the optical window 5, which can reduce the optical path from the front end of the receiving module 2 to the optical window 5.

[0077] In some other embodiments, the rotating shaft 6 has no intersection with the first reflecting surface 301, but may have an intersection with the first reflecting mirror 31. It should be understood that the intersection between the rotating shaft 6 and the first reflecting mirror 31 does not affect the reduction of the optical path from the front end of the receiving module 2 to the optical window 5 by the second reflecting surface 302 and the second reflecting mirror 32.

[0078] In some embodiments, the transmitting module 1 has a first optical axis 21, and the receiving module 2 has a second optical axis 22. The projections of the first optical axis 21 and the second optical axis 22 onto a plane are straight lines, and the projections of the transmitting module 1 and the receiving module 2 onto the plane are located on the same side of the scanning component 3. That is, the overall architecture of the transceiver module of this application, which has the transceiver module on the same side off-axis, results in a smaller off-axis amount for transmitting and receiving lasers, and a smaller overall parallax.

[0079] In some embodiments, the first projection and the second projection are two parallel lines. The length of the first projection is greater than the length of the second projection, that is, the length of the first reflector 31 is greater than the length of the second reflector 32. The first reflector 31 is longer to cover a large range of light reflection, and the second reflector 32 is shorter to reduce the optical path from the front surface of the receiving module 2 to the optical window 5, avoid redundant design, reduce material usage, prevent stray light generation, or prevent the excessively long second reflector 32 from blocking the emitted light.

[0080] like Figure 2BAs shown, it should be understood that this application adds a second reflector 32 to the scanning component 3. When the first reflector 31 is rotated to such a position... Figure 2B At the -60° angle shown, the distance from the optical window 5 to the receiving module 2 of the reflected light 10 is shortened by the second reflector 32, so that the energy of the edge field of view in the vertical direction (Z direction) is completely received by the receiving module 2, which improves the receiving efficiency and increases the vertical field of view.

[0081] In some embodiments, the second reflector 32 is parallel to the first reflector 31, and the area of ​​the second reflector 32 is smaller than the area of ​​the first reflector 31. It should be understood that the second reflector 32 and the first reflector 31 are placed parallel to each other and connected as a whole. By swinging or rotating, the laser beam is reflected out or into the radar unit. The propagation path of the laser beam inside the radar unit is more direct and compact, reducing the optical path length of the transmitted and received beams inside the radar unit during scanning, increasing the radar's vertical field of view and transmission / reception efficiency. It can also prevent stray light generation or prevent the excessively long second reflector 32 from blocking the emitted light.

[0082] Furthermore, such as Figure 1A As shown, the second reflective surface 302 and the first reflective surface 301 are projected onto a plane perpendicular to the rotation axis 6, that is, the XY plane of the scanning component 3. The position of the second reflective surface 302 is determined by the relative position of the transmitting module 1 and the receiving module 2. The geometric center O3 of the second reflective surface 302 is projected vertically onto the first reflective surface 301 at point A1. The distance between A1 and the edge of the first reflective surface 301 is L1, where L1 = β = π / 4 - α / 4; where π radians equals 180 degrees; d is the vertical distance between the second reflecting surface 302 and the first reflecting surface 301; D is the diameter of the emitted light spot from the transmitting module 1 of the lidar (i.e., the diameter of the emitted light spot just after leaving the transmitting module 1); α is the field of view angle of the lidar in plane one; and L is the length of the second reflecting surface 302 in plane one.

[0083] It should be understood that the first reflective surface 301 and the second reflective surface 302 are set to be parallel, and the vertical distance d between the first reflective surface 301 and the second reflective surface 302 is set to the critical minimum distance that does not obstruct the normal light output of the transmitting module 1. The geometric center O3 of the second reflective surface 302 is projected onto the first reflective surface 301 at a distance A1 from the end point L1 of the first reflective surface 301 near the receiving module 2. The receiving module 2 and the transmitting module 1 are designed off-axis on the same side, and the second reflective surface 302 is located on the side of the first reflective surface 301 near the transmitting module 1. This not only helps to maximize the recovery rate of the reflected light 10 by utilizing the second reflective surface 302, but also avoids the emitted light from the transmitting module 1 being blocked by the second reflective surface 302 and then reflected multiple times between the first reflective surface 301 and the second reflective surface 302, generating additional stray light, thus improving the overall transceiver efficiency of the lidar.

[0084] Furthermore, such as Figure 1B As shown, the field of view α of the lidar is fixed, and β needs to be defined by α. In a plane perpendicular to the rotation axis 6 (parallel to the Z direction) of the scanning component 3, there is a normal 8 and a horizontal line 9 (parallel to the X direction) perpendicular to the normal 8, to clearly show the area outside the lidar's field of view. 2β = (180° - α) / 2, where 2β is half the angle of the area outside the lidar's detection field of view. Preferably, in plane one, 60° ≤ α ≤ 150°.

[0085] Furthermore, 0 < L ≤ β = π / 4 - α / 4; where π radians equals 180 degrees; d is the vertical distance between the second reflecting surface 302 and the first reflecting surface 301. This design can both reduce the optical path from the front surface of the receiving module 2 to the optical window 5 by utilizing the second reflecting surface 302, thereby improving the receiving efficiency of the edge field of view perpendicular to the rotation direction of the scanning component 3, and avoid the risk of stray light generated by multiple reflections between the first reflecting surface 301 and the second reflecting surface 302, and eliminate the resulting attenuation of emission efficiency. Figure 17 and Figure 18 The principle that the receiving efficiency is improved when the optical path from the receiving module 2 to the optical window 5 is shortened is further illustrated. Specifically, as... Figure 17 As shown in the figure, the boxes formed by dashed lines represent laser beams incident from the edge of the vertical field of view, and the boxes formed by dotted lines represent laser beams incident at 0°. In conventional technology, the distance between receiver 2a and observation window 5a is relatively large. When the laser beam incident from the edge of the vertical field of view reaches receiver 2a from observation window 5a, the energy of the vertical edge of the field of view cannot be completely received by receiver 2a at the position between the effective receiving aperture edge of receiver 2a and the inner wall of the outer casing 6a, i.e., positions A and B in the figure. This results in varying degrees of receiving efficiency loss, and in some cases, no light is received at all. Figure 18As shown in the figure, the boxes formed by dashed lines represent laser beams incident from the edge of the vertical field of view, and the boxes formed by dotted lines represent laser beams incident at 0°. When the distance between the receiving module 2 and the optical window 5 is shortened, when the laser beam incident from the edge of the vertical field of view reaches the receiving module 2 from the optical window 5, the energy of the vertical edge of the field of view can be completely received by the receiving module 2 at the position between the effective receiving aperture edge of the receiving module 2 and the inner wall of the housing 7, i.e., positions A and B in the figure. This effectively improves the receiving efficiency of the laser radar edge field of view. The laser radar of this application achieves this by using the second reflector 32 to shorten the optical path between the receiving module 2 and the optical window 5. Figure 18 The technical effects shown.

[0086] Furthermore, the diameter of the emitted light spot of the LiDAR's transmitting module 1 is D. Specifically, the emitted light spot is the width of the light spot just after leaving the transmitting module 1. Since the length L of the second reflecting surface 302 in plane 1 is greater than 0, the vertical distance d between the second reflecting surface 302 and the first reflecting surface 301 must satisfy the following: β = π / 4 - α / 4; where π radians equals 180 degrees; d is the vertical distance between the second reflecting surface 302 and the first reflecting surface 301. This ensures that both the first reflecting surface 301 and / or the second reflecting surface 302 can effectively reflect the reflected light 10 to the receiving module 2, thus ensuring the normal operation of the lidar.

[0087] Furthermore, such as Figure 2A As shown, the scanning component 3 can rotate around the rotating shaft 6. When the scanning component 3 rotates, the first reflective surface 301 and the second reflective surface 302 rotate synchronously around the rotating shaft 6. The rotating shaft 6 is parallel to the first reflective surface 301 and / or the second reflective surface 302. This avoids the second reflective surface 302 from rotating arbitrarily during the rotation of the scanning component 3 around the rotating shaft 6, thus preventing the emitted laser from being disturbed by multiple reflections of the emitted light and generating additional stray light, thereby improving the overall transmission and reception efficiency of the lidar.

[0088] Furthermore, such as Figure 1A As shown, the rotating shaft 6 is schematically represented as the rotation center O1 on the XY plane (plane one), the midpoint of the first reflecting surface 301 is O2, and the midpoint of the second reflecting surface 302 is O3. The rotating shaft 6 is located on the side of the first reflecting surface 301 away from the second reflecting surface 302. In plane one, the rotation center O1 of the rotating shaft 6, the midpoint O2 of the first reflecting surface 301, and the midpoint O3 of the second reflecting surface 302 are not collinear, thereby avoiding mutual interference of light between the reflecting surfaces and ensuring that light can pass smoothly through the scanning component 3 to reach the optical window 5.

[0089] In some embodiments, the rotating shaft 6 is parallel to the first reflecting surface 301 and / or the second reflecting surface 302, which makes the overall stability of the scanning component 3 high, the relative error between the two mirrors small, and facilitates subsequent calibration. In some embodiments, the rotating shaft 6 may also have a certain tilt angle with the first reflecting surface 301 and / or the second reflecting surface 302, which is not specifically limited in this application.

[0090] like Figure 3 The diagram shows a conventional lidar system without a second reflector 32. The transmitter 1a emits a laser beam, which is reflected by reflector 4a to scanner 3a. The laser beam is then reflected by scanner 3a to the outside of observation window 5a. After being reflected by a target outside observation window 5a, it forms a retroreflected beam. This retroreflected beam passes through observation window 5a and is reflected again by scanner 3a before being collected by receiver 2a. When the first reflector 31 is rotated to the -60° angle shown in the diagram, the distance from observation window 5a to receiver 2a is longer. This results in the receiver 2a not being able to fully receive the energy at the edge of the field of view in the vertical direction, leading to varying degrees of reception efficiency loss, and even situations where no light is received. This fails to meet the requirements for the overall edge field of view reception efficiency.

[0091] Solving the above problems requires balancing the overall size (especially the height), the effective aperture of the transceiver module, and the size of the scanning module. However, this introduces new challenges. For example, a large scanning module occupies more space, increasing the optical path of the reflected beam from the observation window 5a to the receiver 2a. This increased optical path leads to reduced transceiver efficiency in the height-limited edge field of view of the lidar, ultimately resulting in poorer range finding performance at the edge field of view. Furthermore, a large scanning module occupies more space during rotation. In the edge field of view within the rotation plane, transmitting and receiving lasers requires more space to prevent physical obstruction, significantly increasing the space required for lidar design and thus increasing the overall size of the system.

[0092] On the other hand, for scanning lidar with an off-axis architecture on the same side, in order to meet the requirement of sufficient effective optical aperture, the spacing of the optical axis 20 of the transceiver module needs to be increased. However, this will lead to an increase in the size of the scanner 3a and the overall size of the device. At the same time, the increase in size will lead to a decrease in the transceiver efficiency at the edge of the field of view.

[0093] The scanning component 3 of the lidar in this application utilizes a double-layer reflective surface to reduce the distance between the optical window 5 and the receiving module 2. This not only effectively improves the laser receiving efficiency but also simultaneously satisfies the technical requirements of lidar for small size, good edge field of view ranging performance, and prevention of stray light obstruction.

[0094] Furthermore, the lidar of this application includes at least one scanning component 3. The emitted light is emitted outside the optical window 5 via the first reflecting surface 301 and / or the second reflecting surface 302. After being reflected by the external object to be detected, it forms a retroreflected light 10. After the retroreflected light 10 passes through the optical window 5, it is reflected by the first reflecting surface 301 and / or the second reflecting surface 302 and is collected by the receiving module 2.

[0095] Furthermore, when both the first reflecting surface 301 and the second reflecting surface 302 face the receiving module 2, the second reflecting surface 302 is located between the first reflecting surface 301 and the receiving module 2, so that during the rotation of the rotating shaft 6, at least a portion of the second reflecting surface 302 can face the receiving module 2 within the applicable field of view, thereby enabling the reflected light 10 reflected by the second reflecting surface 302 to be collected by the receiving module 2 efficiently and completely.

[0096] In some embodiments, the lidar further includes a reflection module 4, which is disposed on the light output path of the transmitting module 1 and is used to reflect the emitted light to the scanning component 3; or, disposed on the path of the receiving module 2 and is used to reflect the reflected light 10 to the receiving module 2 for acquisition by the receiving module 2.

[0097] In some embodiments, such as Figure 4 As shown, the lidar includes two reflection modules 4, which are respectively located on the light output path of the transmitting module 1 and the light input path of the receiving module 2. Since the transmitting module 1 and the receiving module 2 are arranged in parallel, the receiving module 2 needs to use another reflection module 4 so that the parallel receiving module 2 can successfully receive the reflected laser.

[0098] In some embodiments, such as Figure 5 As shown, the lidar can also be without the reflection module 4. Since the transmitting module 1 and the receiving module 2 are set in parallel, the transmitting module 1 can directly reflect the laser to the outside of the optical window 5 through the first reflecting surface 301, and the receiving module 2 can directly collect the reflected light 10 through the second reflecting surface 302.

[0099] Furthermore, the transmitting module 1 and the receiving module 2 are arranged off-axis on the same side. "On the same side, off-axis" means that both the transmitting module 1 and the receiving module 2 are located on one side of the scanning component 3, and their optical axes 20 do not coincide, that is, the first optical axis 21 and the second optical axis 22 do not coincide. Simultaneously, the emitted light from the transmitting module 1 reaching the scanning component 3 is parallel to the main ray 40 of the reflected light 10 from the scanning component 3. Specifically, as shown... Figure 5 As shown, the transmitting module 1 has a first main ray 41, and the receiving module 2 has a second main ray 42. The first main ray 41 and the second main ray 42 are parallel to each other.

[0100] Furthermore, the relative placement of the transmitting module 1 and the receiving module 2 can be arbitrarily set, but it must ensure that the principal rays 40 of the emitted light and reflected light 10 passing through the scanning component 3 are parallel. It should be understood that parallelism between the principal rays 40 of the emitted and reflected light 10 makes the optical path more regular and stable. During beam transmission, the reflected light 10 can better match the optical path of the emitted light, reducing undesirable optical phenomena such as scattering and interference caused by non-parallelism of the principal rays 40. For example, in a laser ranging system, this parallel arrangement of the principal rays 40 ensures that the reflected light 10 accurately enters the receiving module 2, reducing light energy loss, improving measurement accuracy and reliability, and avoiding measurement errors caused by deviations in the principal rays 40.

[0101] Preferably, the off-axis distance between the transmitting module 1 and the receiving module 2 is N, which is the distance between the optical axes 20 of the transmitting module 1 and the receiving module 2. The off-axis distance N between the transmitting module 1 and the receiving module 2 is 0 < N < (R1 + R2) / 2, where R1 is the diameter of the mechanical aperture of the transmitting module 1 and R2 is the diameter of the mechanical aperture of the receiving module 2. When 0 < N < (R1 + R2) / 2, the off-axis distance for transmitting and receiving lasers is smaller, resulting in a smaller overall parallax, improving the measurement accuracy of the lidar system, and simultaneously increasing the laser transmission and reception efficiency.

[0102] The transmitting module 1 of this application uses the reflecting module 4 to deflect the laser beam, while simultaneously blocking part of the effective receiving aperture of the receiving module 2. Compared with the layout of some conventional laser radars that do not block the receiving module at all, the reduction of the off-axis amount of the main beam 40 of the transmitting and receiving module in this application reduces the impact of parallax on the near-range ranging angle offset, thereby reducing the overall parallax of the laser radar and improving the measurement accuracy of the laser radar.

[0103] In some embodiments, the second reflective surface 302 is located on the side of the first reflective surface 301 closer to the receiving module 2, and the scanning component 3 has different scanning angles as time changes, so that the lidar has multiple detection angles. The scanning component 3 has at least two operating states: Figure 4 , Figure 5 as well as Figure 9A As shown, in the first working state, when detecting the negative edge field of view, the emitted light is emitted from the emitting module 1, reflected by the first reflecting surface 301 and exiting the optical window 5, and the reflected light 10 is recovered by the second reflecting surface 302 and returned to the receiving module 2.

[0104] The scanning component 3 rotates, and the lidar detection area shifts from the negative edge of the field of view to the center of the field of view, which is the second working state. Figure 10A , Figure 11AAs shown, the emitted light is emitted from the transmitting module 1, reflected by the first reflecting surface 301 and the second reflecting surface 302 and exits through the optical window 5, and the reflected light 10 is recovered by the first reflecting surface 301 and the second reflecting surface 302 and returned to the receiving module 2.

[0105] When scanning component 3 rotates and the lidar detection area is at the center of the field of view, it is in working state three. Figure 12A As shown, the emitted light is emitted from the transmitting module 1, reflected by the first reflecting surface 301 and the second reflecting surface 302, and exits through the optical window 5. The reflected light 10 is recovered by the first reflecting surface 301 and returned to the receiving module 2.

[0106] The scanning component 3 rotates, and the lidar detection area shifts from the center field of view to the positive edge field of view, which is the fourth working state. Figure 13 As shown, the emitted light is emitted from the transmitting module 1, reflected by the first reflecting surface 301 and the second reflecting surface 302, and exits through the optical window 5. The reflected light 10 is recovered by the first reflecting surface 301 and returned to the receiving module 2.

[0107] When scanning component 3 rotates, and the lidar detection area is at the positive edge of the field of view, it is in working state five. Figure 14 As shown, the emitted light is emitted from the emitting module 1, reflected by the first reflecting surface 301, and exits through the optical window 5. The reflected light 10 is then recovered by the first reflecting surface 301 and returned to the receiving module 2. It is worth noting that the scanning component 3 undergoes at least two of the aforementioned operating states during its dynamic changes, which are not specifically limited in this application.

[0108] It should be understood that, compared to conventional technologies, the lidar of this application can achieve at least two working states during the dynamic change of the scanning component 3. That is, the lidar of this application with dual reflectors can, at different scanning angles, have the transceiver module using the two reflectors independently, sharing both reflectors simultaneously, or sharing the first reflector 31 to emit and receive light. Specifically, the two reflectors are placed parallel and connected as a whole, but the position of the transceiver module remains unchanged. During rotation, the projection of the transceiver beam will dynamically change on the surface of the two reflectors. The dynamic change of the working condition using the two reflectors reduces the maximum optical path while maintaining the performance of other fields of view, thereby improving the lower limit of the ranging performance of the entire lidar.

[0109] In some embodiments, the position and arrangement of the transmitting module 1 and the receiving module 2 can be parallel or completely adjacent to each other, making the overall lidar more compact and realizing the miniaturization of the lidar.

[0110] like Figure 4As shown, the transmitting module 1 has a first optical axis 21, and the receiving module 2 has a second optical axis 22. The optical axes 20 of the transmitting module 1 and the receiving module 2 are arranged parallel to each other, that is, the first optical axis 21 is parallel to the second optical axis 22. Furthermore, the optical axes 20 of both the transmitting module 1 and the receiving module 2 are perpendicular to the optical window 5, that is, both the first optical axis 21 and the second optical axis 22 are perpendicular to the optical window 5. Further, a reflection module 4 is provided on the light output path of the transmitting module 1 to reflect the emitted light outside the optical window 5; a reflection module 4 is also provided on the laser recovery path of the receiving module 2 to change the path of the reflected light 10 from the second reflecting surface 302, thereby allowing the reflected light 10 to enter the receiving module 2.

[0111] like Figure 5 As shown, the first optical axis 21 of the transmitting module 1, the second optical axis 22 of the receiving module 2, and the optical window 5 are arranged in parallel. That is, both the first optical axis 21 and the second optical axis 22 are parallel to the optical window 5, and the transmitting module 1 and the receiving module 2 are close to each other. Specifically, in order to meet the requirements of matching the small-sized scanning component 3, the transmitting module 1 and the receiving module 2 need to be close to each other and one or both sides need to be cut off to meet the requirement of small size of the transmitted and received laser beams. However, it should be noted that cutting off part of the lens of the transmitting module 1 and the receiving module 2 will reduce the amount of laser light entering or exiting the lens. Therefore, in order to increase the transmission and reception efficiency, the lens aperture of the transmitting module 1 and the receiving module 2 needs to be appropriately increased, which in turn requires increasing the spacing of the main beam 40. Furthermore, in this embodiment, the relative placement angle and position of the receiving module 2 can be arbitrary, as long as the emitted laser light exiting the optical window 5 and the reflected light 10 entering the optical window 5 both pass through the reflective surface of the scanning component 3. This setup eliminates the need for a reflection module 4, allowing the transceiver module to transmit and receive lasers directly through the scanning component 3, thus enabling further miniaturization of the lidar.

[0112] In some embodiments, the scanning component 3 can be one or more. Through the coordinated work of multiple scanning components 3, a larger angular range can be covered, improving the detection efficiency of the lidar and reducing blind spots. This is especially suitable for scenarios that require large-scale monitoring, such as the comprehensive perception of the surrounding environment by autonomous vehicles.

[0113] In some embodiments, such as Figure 6As shown (light path not shown), the lidar includes two scanning components 3. These components can be either symmetrical or asymmetrical; this application does not specifically limit their configuration. Furthermore, each scanning component 3 includes a first reflecting surface 301 and a second reflecting surface 302. The two scanning components 3 are connected as a whole and rotate. The two first reflecting surfaces 301 and the two second reflecting surfaces 302 are also considered as a single unit. Connecting the two scanning components 3 as a whole reduces measurement deviations caused by the movement or errors of individual components. The overall structure is more stable, and the relative positional relationship between the reflecting surfaces is more stable, ensuring that the lidar maintains high-precision measurement results even during long-term operation or in complex environments. Simultaneously, rotating and controlling the two scanning components 3 as a whole reduces the complexity of independently controlling multiple components, facilitating subsequent point cloud data fusion and processing.

[0114] Furthermore, the multiple scanning components 3 can have arbitrary angular differences within a plane perpendicular to the rotation axis 6. For example, when the angular difference is 180°, two scanning components 3 are set; when the angular difference is 90°, four scanning components 3 are set. The number of scanning components 3 can be determined by the angular interval of the rotation of the scanning components 3.

[0115] In some embodiments, the two scanning components 3 may have any angular difference in the direction of the rotation axis 6, with the angular difference being greater than or equal to 0°; when the angular difference is greater than 0°, the main rays 40 of the emitted and received beams of the transmitting module 1 and the receiving module 2 may produce additional angular changes, thereby realizing scanning of different fields of view in the vertical direction, increasing the vertical field of view or increasing the resolution in the vertical direction.

[0116] In some embodiments, the scanning component 3 may be a tilting mirror, a galvanometer, a rotating prism, etc. The tilting mirror and the galvanometer have a single scanning component 3, which consists of a first reflecting mirror 31 and a second reflecting mirror 32. The rotating prism, etc., consists of multiple scanning components 3, and each scanning component 3 consists of a first reflecting mirror 31 and a second reflecting mirror 32. Multiple scanning components 3 can achieve scanning at a larger angle by setting the tilt angle of the reflective surface, thereby improving the field of view of the entire lidar device.

[0117] In some embodiments, scanning components 3 with equivalent functions may have slight differences, such as differences in pitch angle (i.e., an angle between the reflective surface and the Z-axis). By designing multiple scanning components 3 with different pitch angles, the functions of different scanning reflective surfaces corresponding to different scanning fields of view can be realized.

[0118] In some embodiments, such as Figure 7 and Figure 8The scanning assembly 3 includes a first reflector 31 and a second reflector 32. The first reflector 31 has a first reflecting surface 301, and the second reflector 32 has a second reflecting surface 302. The first reflector 31 and the second reflector 32 are connected. Specifically, the first reflector 31 and the second reflector 32 are connected by structural components or other connection methods to form an integrated scanning assembly 3, rather than two independent devices. This integrated design ensures that the relative positions of the two reflectors remain unchanged during scanning, thereby significantly improving the stability of the system. Since the two reflectors remain relatively fixed during manufacturing and assembly, the relative error between them can be effectively controlled within a small range, which not only helps to improve the accuracy and reliability of the scanning assembly 3, but also greatly facilitates subsequent calibration work.

[0119] In some embodiments, the scanning assembly 3 may have multiple second reflectors 32, which function as a single unit during rotation. Multiple second reflectors 32 can cover more scanning angles, thereby expanding the scanning range of the entire scanning assembly 3. Furthermore, multiple second reflectors 32 can achieve more complex scanning modes to adapt to different application requirements.

[0120] In some embodiments, such as Figure 7 As shown, the rotary motor is placed at the bottom of the reflector (i.e., the reflector is mounted above the motor in the Z-axis direction). The rotating shaft 6, schematically shown on the XY plane (plane one), has its rotation center O1 coinciding with the midpoint O2 of the first reflector 31. The scanning assembly 3 includes one first reflector 31 and two second reflectors 32. The first reflector 31 has two opposing first reflective surfaces 301, meaning that during the rotation of the scanning assembly 3, both sides of the first reflector 31 have light reflection capabilities. The two second reflectors 32 each have a second reflective surface 302 on the side furthest from the first reflector 31. The two second reflectors 32 are respectively positioned on both sides of the first reflector 31, and both are located at a center furthest from the first reflector 31. This allows both second reflectors 32 to reduce the distance between the optical window 5 and the receiving module 2 during lidar scanning, thereby improving reception efficiency.

[0121] In some embodiments, such as Figure 8As shown, the scanning component 3 includes a first reflector 31 and two second reflectors 32. The first reflector 31 has a first reflective surface 301 facing the optical window 5. The two second reflectors 32 are both disposed on the side away from the first reflector 31 and close to the optical window 5, and each of the two second reflectors 32 has a second reflective surface 302 on the side away from the first reflector 31. Furthermore, the two second reflectors 32 are disposed at a position away from the center of the first reflector 31 and are parallel to it. A gap is provided between the two second reflectors 32. The gap prevents the light beam from being reflected and scattered multiple times between the first reflector 31 and the second reflector 32, thereby reducing stray light. It is worth mentioning that when only a portion of the reflected light 10 is not detected by the receiving module 2, only the corresponding area needs to be equipped with a second reflector 32; it is not necessary to install second reflectors 32 on the entire surface. Using multiple separate second reflectors 32 can avoid the second reflector 32 having an excessively large area, which would increase weight and cost.

[0122] In some embodiments, the scanning component 3 is not limited to a reciprocating mirror; reciprocating or rotating motion is also possible. The scanning component 3 may be a scanning device such as a pendulum mirror, a rotating prism, or a galvanometer, but all of the above-mentioned scanning components 3 have the feature of a reflective surface structure composed of a first reflecting mirror 31 and a second reflecting mirror 32.

[0123] In some embodiments, the optical window 5 may be a plane or a curved surface, and the shape of the optical window 5 is selected according to the specific needs and application scenarios of the lidar.

[0124] This application also provides devices that include any of the aforementioned lidar devices, which may be vehicles, drones, robots, etc., and this application does not impose any specific limitations on them.

[0125] This application also provides specific embodiments of optical system architecture schemes that effectively improve the receiving efficiency of lidar.

[0126]

Example 1

[0127] Example 1 shows a lidar with HFOV (horizontal field of view) α = 120°.

[0128] The lidar in this embodiment consists of an optical window 5, a scanning component 3, a reflection module 4, a transmitting module 1, and a receiving module 2. The optical window 5 is planar and has a length of 110mm.

[0129] Compared to using a single-layer reflective surface as the scanning component 3, the required horizontal length of the optical window 5 is 120mm. In this embodiment, a scanning component 3 with a double-layer reflective surface structure is used. The scanning space occupied by the scanning component 3 remains unchanged, and the required horizontal length of the optical window 5 is reduced to 110mm, which helps to further reduce the overall size of the lidar.

[0130] The length of the first reflecting surface 301 is 50mm;

[0131] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 7.5 mm;

[0132] The diameter D of the emitted light spot from the transmitting module 1 is 8mm;

[0133] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤24mm, while the actual design shows that the length L of the second reflective surface 302 is 22mm.

[0134] In this embodiment, the distance between the geometric center of the second reflective surface 302, the vertical projection point A1 on the first reflective surface 301, and the edge of the first reflective surface 301 is L1=15.5mm±1mm, while the actual design value is L1=16mm.

[0135] In this embodiment, the off-axis distance of the transceiver module is N=8mm, the mechanical aperture diameter of the transmitting module 1 is R1=17.5mm, and the mechanical aperture diameter of the receiving module 2 is R... 2= 18mm.

[0136] Based on the lidar of Example 1, the receiving efficiency of the reflected light 10 in different fields of view was tested.

[0137] like Figures 9A-14 As shown, the direction of the rotation axis 6 of the scanning component 3 is vertical (Z direction), and the scanning component 3 oscillates back and forth in the horizontal plane (XY plane). The scanning component 3 includes a first reflective surface 301 and a second reflective surface 302, which are connected as a whole and set to be parallel to each other, and their relative positions remain unchanged during the oscillation. The transmitting module 1 and the receiving module 2 are placed with the lens optical axis 20 perpendicular to each other. The transmitting module 1 uses the first reflective surface 301 and the second reflective surface 302 to adjust the main ray 40 of the emitted light and the reflected light 10 through the scanning component 3 to be parallel.

[0138] like Figure 9A , Figure 10A and Figure 11AIn the negative angle edge field of view in the horizontal direction, the second reflective surface 302 covers the effective receiving aperture of the receiving module 2, replacing the first reflective surface 301 to realize the reflection function of the reflected light 10. Without sacrificing the receiving efficiency, it reduces the optical path of the reflected light 10 from the optical window 5 to the receiving module 2, thereby improving the receiving efficiency of the lidar edge field of view in the direction of the rotating axis 6 of the scanning component 3. At this time, the length of the second reflective surface 302 is less than the length that would block the emitted beam. After the beam emitted from the transmitting module 1 passes through the reflective surface, it passes through the space between the second reflective surface 302 and the first reflective surface 301, and the first reflective surface 301 emits the emitted beam out of the whole machine. The length L=22mm of the second reflective surface 302 is the size that does not block the emitted beam reflected by the first reflective surface 301.

[0139] Furthermore, the transmitting module 1 uses the reflecting module 4 to deflect the beam, while also partially blocking the effective receiving aperture of the receiving module 2. Compared with the layout scheme that does not block at all, the resulting reduction in the off-axis amount of the main beam 40 of the transmitting and receiving modules reduces the impact of parallax-induced near-range ranging angle offset by more than 50%.

[0140] like Figures 9A-14 At the scanning angle shown, the second reflective surface 302 reduces the optical path of the reflected light 10 inside the lidar, allowing more light from the edge field of view in the vertical direction to enter the receiving module 2. Compared to the overall optical system with only the first reflective surface 301, the receiving efficiency of the lidar edge field of view in this embodiment can be improved by more than 20%.

[0141] Specifically: such as Figure 9A When the scanning component 3 swings to its outermost position, with a horizontal detection field of view of -60°, the transmitting module 1 and the receiving module 2 independently use the first reflecting surface 301 and the second reflecting surface 302, respectively. That is, the emitted light from the transmitting module 1 is entirely reflected by the first reflecting surface 301 out of the optical window 5, and the reflected light 10 is entirely recovered by the second reflecting surface 302 back to the receiving module 2. Because the second reflecting surface 302 reduces the optical path distance between the reflected light 10 and the receiving module 2, such as... Figure 9B The receiver efficiency of the laser radar reflected light 10 with the second reflector 32 is significantly higher than that of the laser radar reflected light 10. Figure 9C LiDAR without a second reflector 32 scheme.

[0142] like Figure 10AThe scanning component 3 swings clockwise from its outermost position. When the horizontal detection field of view is -40°, the transmitting module 1 and the receiving module 2 simultaneously share the first reflecting surface 301 and the second reflecting surface 302. Specifically, the first reflecting surface 301 and the second reflecting surface 302 are used to reflect the emitted light to the outside of the optical window 5. After being reflected by the target object outside the optical window 5, the reflected light 10 is formed. After the reflected light 10 passes through the optical window 5, it can also be reflected to the receiving module 2 through the first reflecting surface 301 and the second reflecting surface 302. Figure 10B The receiver efficiency of the laser radar reflected light 10 with the second reflector 32 is significantly higher than that of the laser radar reflected light 10. Figure 10C LiDAR without a second reflector 32 scheme.

[0143] like Figure 11A The scanning component 3 swings clockwise from its outermost position. When the horizontal detection field of view is -30°, the transmitting module 1 and the receiving module 2 simultaneously share the first reflecting surface 301 and the second reflecting surface 302, as shown below. Figure 11B The receiver efficiency of the laser radar reflected light 10 with the second reflector 32 is higher than that of... Figure 11C LiDAR without a second reflector 32 scheme.

[0144] like Figure 12A The scanning component 3 swings clockwise from its outermost position. When the horizontal detection field of view is 0°, the receiving module 2 uses the first reflecting surface 301 alone, while the transmitting module 1 uses both the first reflecting surface 301 and the second reflecting surface 302 to reflect the laser. Figure 12B The receiver efficiency of the laser radar reflected light 10 with the second reflector 32 is higher than that of... Figure 12C LiDAR without a second reflector 32 scheme.

[0145] like Figure 13 The scanning component 3 swings clockwise from its outermost position. When the horizontal detection field of view is +30°, the receiving module 2 uses the first reflecting surface 301 to collect the reflected light 10, and the transmitting module 1 simultaneously uses the first reflecting surface 301 and the second reflecting surface 302 to reflect the laser. In this embodiment, the receiver efficiency of the reflected light 10 of the lidar with the dual reflecting surface scheme is similar to that of the lidar with the single reflecting surface scheme.

[0146] like Figure 14 The scanning component 3 swings clockwise from the outermost position. When the detection field of view in the horizontal direction is +60°, both the transmitting module 1 and the receiving module 2 use the first reflecting surface 301. In this embodiment, the receiving rate of the LiDAR backlight 10 of the dual reflecting surface scheme is the same as that of the LiDAR of the single reflecting surface scheme.

[0147] As shown in the table below, in the horizontal (X-direction) field of view of 0° and +60°, the receiver efficiency of the reflected light 10 of the lidar with the dual-reflector scheme is the same as that of the lidar with the single-reflector scheme. In the horizontal (X-direction) field of view of -60°, the receiver efficiency of the reflected light 10 of the lidar with the dual-reflector scheme is significantly improved compared to the lidar with the single-reflector scheme at the vertical (Z-direction) angles of 10° and -10°. This indicates that the lidar of this application can effectively improve the receiving efficiency by using the second reflector 302 to reduce the optical path distance between the reflected light 10 and the receiving module 2.

[0148]

[0149] Example 2

[0150] The difference between Example 2 and Example 1 is as follows:

[0151] like Figure 15 Example 2 shows a lidar with HFOV (horizontal field of view) α=100°.

[0152] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 7mm;

[0153] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤15.1mm, while in the actual design, the length L of the second reflective surface 302 is 13mm.

[0154] In this embodiment, the distance between the geometric center of the second reflecting surface 302, the vertical projection point A1 on the first reflecting surface 301, and the edge of the first reflecting surface 301 is L1=11.6mm±1mm, while the actual design value is L1=12.6mm.

[0155] Example 3

[0156] The difference between Example 3 and Example 1 is as follows:

[0157] like Figure 16 Example 3 shows a lidar with an HFOV (horizontal field of view) α = 110°.

[0158] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 7mm;

[0159] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤17.8mm, while in the actual design, the length L of the second reflective surface 302 is 14mm.

[0160] In this embodiment, the distance between the geometric center of the second reflecting surface 302, the vertical projection point A1 on the first reflecting surface 301, and the edge of the first reflecting surface 301 is L1=13.3mm±1.9mm, while the actual design value is L1=13.6mm.

[0161] Example 4

[0162] The difference between Example 4 and Example 1 is as follows:

[0163] like Figure 6 A lidar with two sets of scanning components 3 was presented.

[0164] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 6mm;

[0165] The diameter of the emitted light spot from the transmitting module 1 is D=7mm;

[0166] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤17.7mm, while the actual design length L of the second reflective surface 302 is 16mm.

[0167] In this embodiment, the distance between the geometric center of the second reflective surface 302, the vertical projection point A1 on the first reflective surface 301, and the edge of the first reflective surface 301 is L1=13.5mm±0.8mm, and the actual design value is L1=13.5mm.

[0168] In this embodiment, the off-axis distance of the transceiver module is N=7mm, the mechanical aperture diameter of the transmitting module 1 is R1=16mm, and the mechanical aperture diameter of the receiving module 2 is R... 2= 17mm.

[0169] Example 5

[0170] The difference between Example 5 and Example 1 is:

[0171] like Figure 4 A lidar with a transmitter module 1 and a receiver module 2 arranged side by side and both using a reflector module 4 was presented.

[0172] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 7mm;

[0173] The diameter of the emitted light spot from the transmitting module 1 is D=7mm;

[0174] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤ 23.2 mm, while in the actual design, the length L of the second reflective surface 302 is 22 mm.

[0175] In this embodiment, the distance between the geometric center of the second reflecting surface 302, the vertical projection point A1 on the first reflecting surface 301, and the edge of the first reflecting surface 301 is L1=13.5mm±0.6mm, while the actual design value is L1=13.5mm.

[0176] In this embodiment, the off-axis distance of the transceiver module is N=12mm, the mechanical aperture diameter of the transmitting module 1 is R1=17.5mm, and the mechanical aperture diameter of the receiving module 2 is R... 2= 18mm.

[0177] Example 6

[0178] The difference between Example 6 and Example 1 is:

[0179] like Figure 5 A lidar unit with transmitter module 1 and receiver module 2 arranged side by side was shown.

[0180] The distance d between the first reflecting surface 301 and the second reflecting surface 302 is 8mm;

[0181] The diameter of the emitted light spot from the transmitting module 1 is D=7mm;

[0182] In this embodiment, the theoretical length L of the second reflective surface 302 is ≤ 32.6 mm, while in the actual design, the length L of the second reflective surface 302 is 30 mm.

[0183] In this embodiment, the distance between the geometric center of the second reflecting surface 302, the vertical projection point A1 on the first reflecting surface 301, and the edge of the first reflecting surface 301 is L1=13.5mm±1.8mm, while the actual design value is L1=14mm.

[0184] In this embodiment, the off-axis distance of the transceiver module is N=13mm, the mechanical aperture diameter of the transmitting module 1 is R1=9mm, and the mechanical aperture diameter of the receiving module 2 is R... 2= 17mm.

[0185] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A lidar, comprising: The system comprises a housing, a scanning component, a transmitting module, and a receiving module. The housing has an optical window. The scanning component, the transmitting module, and the receiving module are all located inside the housing. The scanning component is adapted to reflect the emitted light from the transmitting module onto a target object outside the optical window. The reflected light from the target object passes through the optical window and then through the scanning component to the receiving module. The scanning component is adapted to rotate relative to the optical window. The scanning assembly includes a first reflecting mirror and at least one second reflecting mirror that rotate synchronously. The first reflecting mirror and the second reflecting mirror are arranged at intervals. The first reflecting mirror has a first reflecting surface, and the second reflecting mirror has a second reflecting surface. When both the first reflecting surface and the second reflecting surface face the optical window, the second reflecting surface is located between the optical window and the first reflecting mirror. The second reflector is located near the edge of the first reflector.

2. The lidar according to claim 1, characterized in that, The number of the second reflectors is greater than or equal to the number of the first reflectors.

3. The lidar according to claim 2, characterized in that, The scanning component has a rotating axis, the first reflector and the second reflector rotate around the rotating axis, a plane is perpendicular to the rotating axis, the projection of the first reflector onto the plane is a first projection, the projection of the second reflector onto the plane is a second projection, and the distance between the rotating axis and the first projection is less than the distance between the rotating axis and the second projection.

4. The lidar according to claim 3, characterized in that, The second reflecting surface and the first reflecting surface are projected onto a plane perpendicular to the axis of rotation, and the axis of rotation and the second projection have no intersection.

5. The lidar according to claim 4, characterized in that, The rotating shaft does not intersect with the first projection.

6. The lidar according to claim 5, characterized in that, On a plane perpendicular to the rotation axis, the projections of the optical axis of the transmitting module and the optical axis of the receiving module onto the first plane are straight lines, and the projections of the transmitting module and the receiving module onto the first plane are located on the same side of the scanning component.

7. The lidar according to claim 3, characterized in that, The first projection and the second projection are two parallel lines, and the length of the first projection is greater than the length of the second projection.

8. The lidar according to claim 7, characterized in that, The geometric center of the second reflective surface is projected perpendicularly onto the first reflective surface at a point A1, and the distance between A1 and the edge of the first reflective surface is L1. β = π / 4 - α / 4; Where d is the vertical distance between the second reflective surface and the first reflective surface, D is the diameter of the emitted light spot from the laser radar's transmitting module, α is the field of view angle of the laser radar in the plane, and L is the length of the second reflective surface in the plane.

9. The lidar according to claim 8, characterized in that, 60°≤α≤150°。 10. The lidar according to claim 7, characterized in that, 0<L≤ β = π / 4 - α / 4, where d is the vertical distance between the second reflecting surface and the first reflecting surface, D is the diameter of the emitted light spot of the laser radar's transmitting module, α is the field of view of the laser radar in the plane, and L is the length of the second reflecting surface in the plane.

11. The lidar according to claim 7, characterized in that, β = π / 4 - α / 4, where d is the vertical distance between the second reflecting surface and the first reflecting surface, D is the diameter of the emitted light spot from the laser radar's transmitting module, and α is the field of view angle of the laser radar in the plane.

12. The lidar according to any one of claims 3-11, characterized in that, When the first reflective surface and the second reflective surface face the optical window, the rotating axis is located on the side of the first reflective surface away from the second reflective surface. In the plane, the projection of the rotating axis, the midpoint of the first projection, and the midpoint of the second projection are not collinear.

13. The lidar according to any one of claims 1-11, characterized in that, The scanning component has a rotating axis about which the first reflector and the second reflector rotate, and the rotating axis is parallel to the first reflective surface and / or the second reflective surface.

14. The lidar according to any one of claims 1-11, characterized in that, The lidar includes at least one of the scanning components. The emitted light is emitted outside the optical window via the first reflective surface and / or the second reflective surface. After being reflected by the external object being detected, the reflected light is formed. The reflected light passes through the optical window and is reflected by the first reflective surface and / or the second reflective surface to be collected by the receiving module.

15. The lidar according to claim 14, characterized in that, When both the first reflective surface and the second reflective surface face the receiving module, the second reflective surface is located between the first reflective surface and the receiving module.

16. The lidar according to claim 14, characterized in that, It also includes a reflection module, disposed on the light output path of the emission module, for reflecting the emitted light to the scanning component; or, It is positioned on the path of the receiving module to reflect the reflected light back to the receiving module for collection by the receiving module.

17. The lidar according to claim 14, characterized in that, The transmitting module and the receiving module are arranged off-axis on the same side, and the main ray of the emitted light reaching the scanning component is parallel to the main ray of the reflected light after being reflected by the scanning component.

18. The lidar according to claim 17, characterized in that, The off-axis distance of the transmitting module and the receiving module is N, where 0 < N < (R1 + R2) / 2, where R1 is the mechanical diameter of the transmitting module and R2 is the mechanical diameter of the receiving module.

19. The lidar according to claim 14, characterized in that, The second reflective surface is located on the side of the first reflective surface closer to the receiving module, and the scanning component has at least two operating states: In the first working state, the scanning component rotates. When detecting the negative edge field of view, the emitted light is emitted from the emitting module, reflected by the first reflecting surface out of the optical window, and the reflected light is recovered by the second reflecting surface to the receiving module. In the second working state, as the scanning component rotates and the lidar detection area shifts from the negative edge of the field of view to the center of the field of view, the emitted light is emitted from the emitting module, reflected by the first and second reflecting surfaces and exits the optical window, and the reflected light is recovered by the first and second reflecting surfaces and returned to the receiving module. In the third working state, when the scanning component rotates and the lidar detection area is the central field of view, the emitted light is emitted from the transmitting module, reflected by the first and second reflecting surfaces and exits the optical window, and the reflected light is recovered by the first reflecting surface to the receiving module. In the fourth working state, as the scanning component rotates and the lidar detection area shifts from the central field of view to the positive edge field of view, the emitted light is emitted from the emitting module, reflected by the first and second reflecting surfaces, and exits the optical window. The reflected light is then recovered by the first reflecting surface and returned to the receiving module. In operating state five, when the scanning component rotates and the lidar detection area is at the positive edge of the field of view, the emitted light is emitted from the emitting module, reflected by the first reflective surface out of the optical window, and the reflected light is recovered by the first reflective surface to the receiving module.

20. A device comprising the lidar according to any one of claims 1-19.

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