CN112789511A

CN112789511A - Laser radar and autopilot device

Info

Publication number: CN112789511A
Application number: CN201980002234.0A
Authority: CN
Inventors: 马丁昽; 尹向辉; 刘乐天
Original assignee: Suteng Innovation Technology Co Ltd
Current assignee: Suteng Innovation Technology Co Ltd
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2021-05-11
Also published as: WO2021035427A1

Abstract

A laser radar (100) and an autopilot apparatus (200). The laser radar (100) comprises a transmitting module (10), a scanning module (20) and a receiving module (30); the emitting module (10) is used for emitting emergent laser; the scanning module (20) comprises a rotating mirror (21) rotating around a rotating shaft (25), wherein the rotating mirror (21) is used for receiving emergent laser and reflecting the emergent laser to emit to a detection area, and is also used for receiving echo laser and reflecting the echo laser to emit to a receiving module (30); the echo laser is returned after the emergent laser is reflected by an object in the detection area; the receiving module (30) is arranged on the other side of the transmitting module (10) along the direction of the rotating shaft (25) and is used for receiving the echo laser. The miniaturization of the laser radar is realized.

Description

Laser radar and autopilot device

Technical Field

The embodiment of the invention relates to the technical field of radars, in particular to a laser radar and an automatic driving device.

Background

The laser radar is a radar system for detecting characteristic quantities such as the position, the speed and the like of a target object by laser, and the working principle of the radar system is that a transmitting module firstly transmits emergent laser for detection to the target, then a receiving module receives echo laser reflected from the target object, and after the received echo laser is processed, relevant information of the target object, such as parameters of distance, direction, height, speed, attitude, even shape and the like, can be obtained.

The rotary laser radar in the prior art enables the whole laser radar device to rotate around a shaft, and scanning of a detection area is achieved. Because the whole laser radar device needs to rotate around the shaft, the rotating part is heavy, the product size is large, the energy consumption is high, the stability is poor, and the miniaturization can not be further realized.

Disclosure of Invention

In view of the above defects in the prior art, a main object of the embodiments of the present invention is to provide a laser radar and an automatic driving device thereof, which solve the problems of large size, large energy consumption and poor stability of a rotary laser radar in the prior art.

The embodiment of the invention adopts a technical scheme that: the laser radar comprises a transmitting module, a scanning module and a receiving module; the transmitting module is used for transmitting emergent laser; the scanning module comprises a rotating mirror rotating around a rotating shaft, the rotating mirror is used for receiving the emergent laser and reflecting the emergent laser to emit to a detection area, and is also used for receiving the echo laser and reflecting the echo laser to emit to the receiving module; the echo laser is returned after the emergent laser is reflected by an object in the detection area; the receiving module is arranged on the other side of the transmitting module along the direction of the rotating shaft and used for receiving the echo laser.

Optionally, the rotating mirror is a plane mirror.

Optionally, an included angle δ between the rotating shaft and the plane mirror is greater than or equal to 0 ° and less than 90 °.

Optionally, the rotating mirror is a polygonal mirror, and each outer side surface of the polygonal mirror is a reflecting surface.

Optionally, the outgoing laser and the corresponding echo laser at any time are both reflected by the same reflecting surface of the polygon mirror.

Optionally, an included angle between at least one of the reflecting surfaces of the polygon mirror and the rotating shaft is different from an included angle between the other reflecting surfaces of the polygon mirror and the rotating shaft.

Optionally, the angles between the reflection surface of the polygonal mirror and the rotating shaft are the same.

Optionally, the laser radar further includes a beam splitter for isolating the outgoing laser and the echo laser.

Optionally, the light splitting plate includes a fixed light splitting plate, and the fixed light splitting plate is disposed between the transmitting module and the receiving module.

Optionally, the light splitting plate further comprises a rotating light splitting plate, the rotating light splitting plate is fixed with the rotating mirror and rotates along with the rotating mirror, a through hole is formed in the fixed light splitting plate, and the rotating light splitting plate is arranged in the through hole.

Optionally, the laser radar further includes a reflector module, where the reflector module includes a first reflector and a second reflector; the first reflector is arranged on a light path of the emergent laser emitted by the emission module and used for reflecting the emergent laser to the first rotating mirror; the second reflector is arranged on the light path of the echo laser reflected by the second rotating mirror and used for reflecting the echo laser to the receiving module.

Optionally, the emission module includes a laser module, an emission driving module, and an emission optical module; the laser module is used for emitting emergent laser; the emission driving module is connected with the laser module and is used for driving and controlling the laser module to work; the emission optical module is arranged on a light path of the emergent laser emitted by the laser module and is used for collimating the emergent laser.

Optionally, the laser module is a laser linear array, and includes a lasers, where a is an integer and a is greater than or equal to 1, and the laser linear array is arranged along the direction of the rotating shaft.

Optionally, the emission optical module is a telecentric lens, and the telecentric lens is configured to collimate each beam of the emitted laser light emitted by the laser module, and deflect the emitted laser light toward a central optical axis of the telecentric lens.

Optionally, the scanning module further includes a driving device and a transmission device, the driving device is provided with an output shaft, the output shaft is connected with the rotating mirror through the transmission device, and the output shaft of the driving device drives the rotating mirror to rotate.

Optionally, the receiving module includes a detector module, a receiving driving module and a receiving optical module; the receiving optical module is arranged on a light path of the echo laser reflected by the scanning module and is used for converging the echo laser; the detector module is used for receiving the echo laser converged by the receiving optical module; the receiving driving module is connected with the detector module and used for driving and controlling the detector module to work.

Optionally, the detector module is a detector linear array and includes k × a detectors, where a is an integer and a is greater than or equal to 1, k is an integer and k is greater than or equal to 1, each laser corresponds to k detectors, and the detector linear array is arranged along the direction of the rotating shaft.

Optionally, the receiving optical module is a telecentric lens, and the telecentric lens is configured to converge the echo laser light and make each beam of the echo laser light incident perpendicular to the detector linear array.

The embodiment of the invention also provides automatic driving equipment which comprises an equipment body and the laser radar, wherein the laser radar is arranged on the equipment body.

The embodiment of the invention has the beneficial effects that: compared with the prior art in which the whole device needs to be driven to rotate together, the laser radar provided by the embodiment of the invention has fewer parts which need to be driven to rotate, and smaller product size, and realizes the miniaturization of the laser radar.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 shows a block diagram of a lidar provided by an embodiment of the present invention;

FIG. 2 is a block diagram of a lidar constructed in accordance with another embodiment of the present invention;

FIG. 3 is a schematic diagram showing an optical path structure of the lidar of FIG. 2;

FIG. 4 is a schematic structural diagram of a turning mirror provided by an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of another turning mirror provided by an embodiment of the present invention;

FIG. 6a is a schematic diagram of an optical path in a vertical plane parallel to the rotation axis of a plane mirror according to an embodiment of the present invention;

FIG. 6b is a schematic diagram showing an optical path in a vertical plane with an included angle α between a plane mirror and a rotating shaft according to an embodiment of the present invention;

FIG. 6c is a schematic diagram of an optical path in a vertical plane with an included angle- α between the plane mirror and the rotation axis according to an embodiment of the present invention;

FIG. 7 is a schematic diagram showing light paths of three mirrors in an embodiment of the present invention, where each reflecting surface is arranged parallel to a rotating shaft;

FIG. 8 is a schematic diagram of an optical path in which an included angle between each reflecting surface of the three-sided mirror and the rotating shaft is- α in the embodiment of the present invention;

FIG. 9a is a schematic diagram of an optical path in a vertical plane with an included angle α between a reflection surface a of a triple mirror and a rotation axis according to an embodiment of the present invention;

FIG. 9b is a schematic diagram of an optical path in a vertical plane with an included angle β between the reflection surface b of the triple mirror and the rotation axis according to the embodiment of the present invention;

FIG. 9c is a schematic diagram of an optical path in a vertical plane with an included angle γ between the reflective surface c of the triple mirror and the rotation axis according to the embodiment of the present invention;

FIG. 10a is a schematic diagram illustrating an angle of view in a vertical plane with an angle of 0 ° between a reflection surface a of a tri-mirror and a rotation axis in an exemplary embodiment of the invention;

FIG. 10b is a schematic diagram showing an angle of view in a vertical plane with an angle of 12.5 ° between a reflection surface b of the tri-mirror and the rotation axis in an exemplary embodiment of the invention;

FIG. 10c is a schematic diagram showing an angle of view in a vertical plane with an angle of 25 ° between the reflection surface c of the tri-mirror and the rotation axis in an exemplary embodiment of the invention;

FIG. 11 is a schematic diagram showing an angle of view in a vertical plane with an angle of-12.5 ° between the reflective surface c of the tri-mirror and the rotation axis in another exemplary embodiment of the invention;

FIG. 12a is a schematic diagram showing an angle of view in a vertical plane with an angle of 5 ° between a reflection surface b of a tri-mirror and a rotation axis in another exemplary embodiment of the present invention;

FIG. 12b is a schematic diagram showing the field angle in the vertical plane with an angle of 10 ° between the reflection surface c of the tri-mirror and the rotation axis in another exemplary embodiment of the present invention;

FIG. 13 shows a schematic diagram of the resolution of the lidar shown in FIGS. 10a, 12 b;

FIG. 14 is a schematic diagram showing an angle of view in a vertical plane with an angle of-5 ° between the reflective surface c of the tri-mirror and the rotation axis in another exemplary embodiment of the present invention;

FIG. 15 shows a schematic diagram of the resolution of the lidar shown in FIGS. 10a, 12a, 14;

fig. 16 is a schematic diagram illustrating an optical path structure of a laser radar according to another embodiment of the present invention;

fig. 17 is a block diagram illustrating a lidar according to another embodiment of the present invention;

fig. 18 is a block diagram illustrating a lidar according to another embodiment of the present invention;

fig. 19 is a schematic diagram showing the optical path structure of the laser bar and the transmitting optical module in fig. 18;

fig. 20 is a schematic diagram showing the optical path structures of the detector array and the receiving optical module in fig. 18;

FIG. 21 is a schematic partial optical path diagram of the emission optical module as a telecentric lens;

FIG. 22 is a schematic partial optical path diagram of a receiving optical module as a telecentric lens;

fig. 23 is a schematic structural diagram of an autopilot apparatus provided by an embodiment of the invention;

fig. 24 is a schematic structural diagram of an autopilot apparatus according to another embodiment of the present invention.

The reference numbers in the detailed description are as follows:

the laser radar device comprises a laser radar 100, a transmitting module 10, a laser module 11, a transmitting driving module 12, a transmitting optical module 13, a scanning module 20, a rotating mirror 21, a first rotating mirror 211, a second rotating mirror 212, a plane mirror 21a, a three-sided mirror 21b, a driving device 22, a transmission device 23, an output shaft 24, a rotating shaft 25, a receiving module 30, a detector module 31, a receiving driving module 32, a receiving optical module 33, a beam splitter 40, a fixed beam splitter 41, a rotating beam splitter 42, a through hole 43, a reflector module 50, a first reflector 51, a second reflector 52, an automatic driving device 200 and a device body 201.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and therefore are only examples, and the protection scope of the present invention is not limited thereby.

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which the present invention belongs.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

Fig. 1 shows a block diagram of a lidar provided in an embodiment of the present invention, and as shown in fig. 1, the lidar 100 includes a transmitting module 10, a scanning module 20, and a receiving module 30. The emitting module 10 is used for emitting emergent laser; the scanning module 20 is configured to receive the outgoing laser and reflect the outgoing laser to the detection area, and receive the echo laser and reflect the echo laser to the receiving module 30, where the echo laser is a laser returned after the outgoing laser is reflected by an object in the detection area; the receiving module 30 is used for receiving the echo laser, and the receiving module 30 is disposed on the other side of the transmitting module 10 along the direction of the rotating shaft 25. The emitting module 10 and the receiving module 30 are both fixed, only the scanning module 20 rotates around a rotating shaft 25, and the emergent laser emitted outwards after being reflected by the scanning module 20 realizes the scanning of the detection area; meanwhile, the scanning module 20 receives the echo laser, reflects the echo laser and transmits the reflected echo laser to the receiving module 30, so as to obtain the information of the target object in the detection area. Compared with the prior art that the transmitting module and the receiving module need to be driven to integrally rotate to scan the detection area, the embodiment of the invention reduces the rotating parts, so that the size of the rotating part can be reduced, the size, the power consumption and the like of the driving device are further reduced, the product size of the whole laser radar 100 is reduced, the energy consumption is reduced, and the use stability is improved.

The emitting laser emitted by the emitting module 10 is reflected by the scanning module 20 and then emitted to the detection area, the echo laser is obtained after the detection area is reflected by the object, and the echo laser is emitted to the receiving module 30 after being reflected by the scanning module 20 and finally received by the receiving module 30.

Fig. 2 shows a block diagram of a lidar according to another embodiment of the present invention, and as shown in fig. 2, the lidar 100 further includes a beam splitter 40, where the beam splitter 40 is disposed between the transmitting module 10 and the receiving module 30, and is used for isolating the outgoing laser and the echo laser. Keep apart emergent laser and echo laser through beam splitter 40, can reduce the crosstalk between emergent laser and the echo laser, avoid emergent laser to the influence of echo light path, improve receiving module's detection accuracy.

Fig. 3 shows a schematic diagram of an optical path structure of the laser radar 100 in fig. 2, as shown in fig. 3, the beam splitter 40 is perpendicular to the rotating shaft 25, and the transmitting module 10 and the receiving module 30 are disposed along the rotating shaft 25, that is, vertically up and down.

The scanning module 20 includes a rotating mirror 21 rotating around a rotating shaft 25, and the rotating mirror 21 is used for receiving the emitted laser and reflecting the emitted laser to the detection area, and receiving the echo laser and reflecting the echo laser to the receiving module 30.

As shown in fig. 3, the turning mirror 21 includes a first turning mirror 211 and a second turning mirror 212; the first rotating mirror 211 is disposed on a first side (lower side in this embodiment) of the beam splitter 40, and is disposed on the same side as the emitting module 10, and is used for reflecting the outgoing laser; the second rotating mirror 212 is disposed on a second side (upper side in the embodiment) of the beam splitter 40, and disposed on the same side as the receiving module 30 for reflecting the echo laser. Optionally, the receiving module 30 and the first rotating mirror 211 are disposed on the first side of the beam splitter 40, and the first rotating mirror 211 is configured to reflect the echo laser; the emission module 10 and the second rotating mirror 212 are disposed on the second side of the beam splitter 40, and the second rotating mirror 212 is used for reflecting the outgoing laser.

The first rotating mirror 211 and the second rotating mirror 212 may be integrally provided as one rotating mirror 21, that is, they are an integral structure, and the rotating mirror 21 is divided into two parts based on the beam splitter 40; the first turning mirror 211 and the second turning mirror 212 may also be provided as two independent turning mirrors 21, each of the two turning mirrors 21 turning around the turning shaft 25. When the first turning mirror 211 and the second turning mirror 212 are two independent turning mirrors 21, the first turning mirror 211 and the second turning mirror 212 may be disposed coplanar and rotate synchronously.

The specific structure of the rotating mirror 21 may be various, and may be a single-face mirror or a polygon mirror, and when the rotating mirror is a polygon mirror, the outgoing laser light and the echo laser light are reflected by the same reflecting surface of the polygon mirror at any time. Fig. 4 is a schematic structural diagram of a rotating mirror according to an embodiment of the present invention, and referring to fig. 3 and fig. 4, the rotating mirror 21 is a flat mirror 21a, which may be a single-sided flat mirror or a double-sided flat mirror. Fig. 5 shows a schematic structural diagram of another turning mirror provided in an embodiment of the present invention, as shown in fig. 5, the turning mirror 21 is a three-sided mirror 21b, the three-sided mirror 21b is in a triangular prism shape, and three outer side surfaces of the three-sided mirror 21b are reflective surfaces. When one of the reflecting surfaces of the three-surface mirror 21b is used for reflecting the outgoing laser light, the reflecting surface is also used for reflecting the corresponding echo laser light. That is, for a certain path of emergent laser and the corresponding echo laser, the same reflecting surface reflects the emergent laser and the corresponding echo laser.

The reflecting surface of the rotating mirror 21 and the rotating shaft 25 may be arranged in an included angle or in parallel (the parallel arrangement is that the included angle between the reflecting surface of the rotating mirror 21 and the rotating shaft 25 is 0 °), because the positions of the transmitting module 10 and the receiving module 30 are fixed, the transmitting direction of the transmitting module 10 and the receiving direction of the receiving module 30 are fixed, and when the angles between the reflecting surface of the rotating mirror 21 and the rotating shaft 25 are different, the angles of the outgoing laser and the echo laser and the reflecting surface of the rotating mirror 21 are different, so that the angle ranges in the vertical direction covered by the vertical angle of view of the laser radar 100 are also different. The included angle between the reflecting surface of the rotating mirror 21 and the rotating shaft 25 is not limited, and can be selected within the range of-90 degrees to 90 degrees. For the triple mirror 21b, the included angle between at least one reflecting surface and the rotation axis 25 may be different from the included angle between the other reflecting surfaces and the rotation axis 25, so that the extended splicing of the vertical viewing angle can be generated.

The following description of directions or orientations should be understood to refer to directions or orientations in a vertical plane. In addition, the rotation shaft 25 is drawn as a rotation axis in a simplified manner in the optical path configuration diagram. Since the optical path is reversible, the following description is made only by the outgoing laser light, and the propagation process of the echo laser light is opposite to that of the outgoing laser light.

As shown in fig. 6a, the plane mirror 21a is disposed parallel to the rotation axis 25, and the emitted laser beam enters the plane mirror 21a along the direction perpendicular to the rotation axis 25, i.e., the horizontal direction, and is reflected in the same horizontal plane. In the figure, l is a normal line of the flat mirror 21 a.

The plane mirror 21a forms an included angle with the rotating shaft 25, the angle range in the vertical direction covered by the vertical field angle formed by the plane mirror 21a is correspondingly deflected, and the deflection angle is twice of the included angle: as shown in fig. 6b, if the included angle between the plane mirror 21a and the rotating shaft 25 is α, the normal line l of the plane mirror 21a rotates in the counterclockwise direction α, at this time, the outgoing laser beam enters the plane mirror 21a along the direction perpendicular to the rotating shaft 25, that is, the horizontal direction, the included angle between the outgoing laser beam entering the plane mirror 21a and the normal line of the plane mirror is α, the plane mirror 21a reflects the outgoing laser beam on the other side of the normal line, and the included angle between the reflected outgoing laser beam and the normal line is also α, compared with fig. 6a, after the outgoing laser beam in fig. 6b is reflected by the plane mirror 21a, the outgoing laser beam rotates 2 α, that is, the angle range in the vertical direction covered by the vertical viewing angle of the plane mirror 21a will deflect.

As shown in fig. 6c, when the angle between the plane mirror 21a and the rotation axis 25 is- α, the normal line l of the plane mirror 21a rotates in the clockwise direction α, and at this time, the emitted laser beam enters the vertical angle of view formed by the reflection of the plane mirror 21a, and the covered angle range in the vertical direction is deflected upward by 2 α compared to fig. 6 a.

When the plane mirror 21a is a double-sided plane mirror, the included angle between the front side and the rotating shaft 25 is alpha, and the included angle between the back side and the rotating shaft 25 is-alpha; as before, the front deflects the vertical field of view upwards by 2 α, and the back deflects the vertical field of view downwards by 2 α; the integral vertical field angle of the laser radar 100 formed by the one-circle rotation scanning of the double-sided plane mirror is formed by splicing the vertical field angles formed by the front surface and the back surface; due to the fact that the vertical direction is deviated, expansion splicing can be formed, and the integral vertical field angle is enlarged.

For the laser radar 100 using the three-mirror 21b as the rotating mirror 21, the three-mirror 21b has three reflecting surfaces, and the three-mirror 21b rotates around the rotating shaft 25, if angles between the three reflecting surfaces and the rotating shaft 25 are the same, three vertical viewing angles formed by the three reflecting surfaces are overlapped, and at this time, the laser radar 100 does not have splicing of the vertical viewing angles; if the angles between the three reflecting surfaces and the rotating shaft 25 are different, for example, the included angle between one reflecting surface and the rotating shaft 25 is different from the included angles between the other reflecting surfaces and the rotating shaft 25, the vertical angle of view formed by the outgoing laser passing through the reflecting surface will be different from the angle range in the vertical direction covered by the vertical angle of view formed by the other reflecting surfaces, that is, the formed vertical angle of view is dislocated in the vertical direction; the principle is similar to that of the plane mirror 21a described above, and is not described herein again; splicing a plurality of vertical field angles is realized through dislocation expansion in the vertical direction, and the integral vertical field angle of the laser radar 100 is enlarged; if the included angle between each reflecting surface and the rotating shaft 25 is different, the overall vertical field angle of the laser radar 100 is formed by splicing the vertical field angles formed by the three reflecting surfaces.

As shown in fig. 7, each reflection surface of the triple mirror 21b is arranged parallel to the rotation axis 25, and at this time, for each reflection surface, the emitted laser light enters the triple mirror 21b along the direction perpendicular to the rotation axis 25, that is, the laser light is reflected in the same horizontal plane after entering the triple mirror along the horizontal direction, the angle range in the vertical direction covered by the vertical field angles formed by the three reflection surfaces is the same, so that the vertical field angle splicing does not occur, and the overall vertical field angle of the laser radar 100 is the same as the vertical field angle formed by the three reflection surfaces.

As shown in fig. 8, each reflection surface of the triple mirror 21b has an angle of- α with the rotation axis 25, and at this time, for each reflection surface, the angle between the outgoing laser beam incident on the reflection surface and the normal of the reflection surface is α, and compared with fig. 7, the angle range in the vertical direction covered by the vertical angle of view of each reflection surface in fig. 8 is deflected upward by 2 α, and since the angle between each reflection surface and the rotation axis 25 is equal, the vertical angle of view formed by each reflection surface is deflected upward by 2 α, and the entire vertical angle of view of the laser radar 100 is deflected upward by 2 α.

Fig. 9a to 9c are schematic diagrams of optical path structures in which the included angles between each reflection surface of the triple mirror 21b and the rotation axis 25 are different. As shown in fig. 9a, the angle between the reflection surface a of the triple mirror 21b and the rotation axis 25 is α, as shown in fig. 9b, the angle between the reflection surface b of the triple mirror 21b and the rotation axis 25 is β, and as shown in fig. 9c, the angle between the reflection surface c of the triple mirror 21b and the rotation axis 25 is γ.

As shown in fig. 9a, at this time, the outgoing laser beam enters the reflection surface a along the direction perpendicular to the rotation axis 25, i.e., the horizontal direction, and the angle between the outgoing laser beam entering the reflection surface and the normal of the reflection surface is α, compared with fig. 7, the angle range in the vertical direction covered by the vertical angle of view formed by the reflection surface a in fig. 9a is deflected downward by 2 α.

Similarly, as shown in fig. 9b, for the reflection surface b, the angle between the emitted laser beam and the normal of the reflection surface b is β, and the angle range in the vertical direction covered by the vertical angle of view formed by the reflection surface b will be deflected downward by 2 β.

As shown in fig. 9c, the angle between the outgoing laser beam and the normal of the reflecting surface c is γ, and the angle range in the vertical direction covered by the vertical angle of view formed by the reflecting surface c will be deflected downward by 2 γ.

The overall vertical field angle of the laser radar 100 is formed by splicing the vertical field angles formed by the three reflecting surfaces.

In an exemplary embodiment, based on the triple-mirror 21b in fig. 9a to 9c, please refer to fig. 10a to 10c, as shown in fig. 10a, an angle between the reflection surface a of the triple-mirror 21b and the rotation axis 25 is 0 °, as shown in fig. 10b, an angle between the reflection surface b of the triple-mirror 21b and the rotation axis 25 is 12.5 °, as shown in fig. 10c, and an angle between the reflection surface c of the triple-mirror 21b and the rotation axis 25 is 25 °. The vertical field angle formed by the single reflecting surface is 25 degrees. As shown in fig. 10b, the vertical angle of view formed by the reflecting surface b is deflected downward by 25 ° (12.5 × 2) in the vertical direction with respect to the vertical angle of view formed by the reflecting surface a; as shown in fig. 10c, the vertical angle of view formed by the reflecting surface c is deflected downward by 50 ° (25 × 2) in the vertical direction with respect to the vertical angle of view formed by the reflecting surface a; in the figure, the area a is the vertical angle of view of the reflecting surface a, the area B is the vertical angle of view of the reflecting surface B, the area C is the vertical angle of view of the reflecting surface C, and the vertical angles of view of the three reflecting surfaces are almost seamlessly spliced to be 75 ° (25+25+ 25). The included angles between the three reflecting surfaces and the rotating shaft are in an arithmetic progression, so that the angle difference of dislocation of three vertical field angles formed by the three reflecting surfaces along the vertical direction is the same, for example, the center of the reflecting surface a is aligned to the vertical direction by 0 degree, the center of the reflecting surface b is aligned to the vertical direction by-12.5 degrees, and the center of the reflecting surface is aligned to the vertical direction by-25 degrees; the formed three vertical field angles can be spliced just right, the boundaries are intersected without an overlapping area, the integral vertical field angle formed after splicing can be the largest, and the field angles formed by different reflecting surfaces are staggered along the vertical direction to be the largest.

In another exemplary embodiment, based on the triple mirror 21b in fig. 9a-9c, please refer to fig. 11, which is different from fig. 10c in that the included angle between the reflective surface c and the rotation axis 25 in the exemplary embodiment is opposite to the reflective surface b, and the included angle is-12.5 °. As shown in fig. 11, the vertical angle of view formed by the reflecting surface c is offset upward by 25 ° (-12.5 × 2) in the vertical direction with respect to the vertical angle of view formed by the reflecting surface a; the vertical field of view of the three reflective surfaces will also be almost seamlessly stitched to 75 ° (25+25+ 25).

In another exemplary embodiment, based on the triple mirror 21b in fig. 9a-9c, as shown in fig. 10a, the angle between the reflection surface a and the rotation axis 25 is 0 °, as shown in fig. 12a, the angle between the reflection surface b and the rotation axis 25 is 5 °, as shown in fig. 12b, the angle between the reflection surface c and the rotation axis 25 is 10 °. The vertical field angle formed by the single reflecting surface is 25 degrees. As shown in fig. 12a, the vertical angle of view formed by the reflecting surface b is deflected downward by 10 ° (5 × 2) in the vertical direction with respect to the vertical angle of view formed by the reflecting surface a; as shown in fig. 12b, the vertical angle of view formed by the reflecting surface c is deflected downward by 20 ° (10 × 2) in the vertical direction with respect to the vertical angle of view formed by the reflecting surface a; the perpendicular field angles of the three reflective surfaces will be 45 ° (25+20) tiled.

Fig. 13 is a schematic view of the angle of view of the laser radar 100 shown in fig. 10a, 12a, and 12 b. In the figure, the viewing angle formed by the reflecting surface a covers an X1+ Y1+ Z area, the viewing angle formed by the reflecting surface b covers a Y1+ Z + Y2 area, the viewing angle formed by the reflecting surface c covers a Z + Y2+ X2 area, namely, an X1 area is only covered by the viewing angle of the reflecting surface a, a Y1 area is covered by the viewing angles of the reflecting surface a and the reflecting surface b, a Z area is covered by the viewing angles of the reflecting surface a, the reflecting surface b and the reflecting surface c, a Y2 area is covered by the viewing angles of the reflecting surface b and the reflecting surface c, and an X2 area is only covered by the viewing angle of the reflecting surface c. The scanning density of the Z area is the maximum, the resolution is the highest, and the resolutions of three field angles of a reflecting surface a, a reflecting surface b and a reflecting surface c are superposed; the Z Region can be detected as a Region of Interest (ROI). The Y1 area and the Y2 area have the next highest resolution, the Y1 area is superimposed by the resolution of the two angles of view of the reflective surface a and the reflective surface b, and the Y2 area is superimposed by the resolution of the two angles of view of the reflective surface b and the reflective surface c. The resolution of the X1 region and the X2 region is the lowest, the resolution of the X1 region is the resolution of the angle of view formed by the reflection surface a, and the resolution of the X2 region is the resolution of the angle of view formed by the reflection surface c.

In another exemplary embodiment, based on the triple mirror 21b in fig. 9a-9c, please refer to fig. 14, which is different from the embodiment shown in fig. 10a, 12a, and 12b in that the included angle between the reflective surface c and the rotation axis 25 in this exemplary embodiment is opposite to the reflective surface b. As shown in fig. 14, the angle between the reflective surface c of the triple mirror 21b and the rotation axis 25 is-5 °. The vertical field angle formed by the single reflecting surface is 25 degrees. The vertical angle of view formed by the reflecting surface c is deflected by 10 degrees (-5 x 2) upwards in the vertical direction relative to the vertical angle of view formed by the reflecting surface a; the vertical field of view of the three reflective surfaces will be tiled at 45 ° (10+25+ 10).

Fig. 15 is a graph showing the scanning density of the laser radar 100 shown in fig. 10a, 12a, and 14. In the figure, the viewing angle formed by the reflecting surface a covers the area Y1+ Z + Y2, the viewing angle formed by the reflecting surface b covers the area Z + Y2+ X2, the viewing angle formed by the reflecting surface c covers the area X1+ Y1+ Z, namely the area X1 is covered by the viewing angle of the reflecting surface c only, the area Y1 is covered by the viewing angles of the reflecting surface a and the reflecting surface c, the area Z is covered by the viewing angles of the reflecting surface a, the reflecting surface b and the reflecting surface c, the area Y2 is covered by the viewing angles of the reflecting surface a and the reflecting surface b, and the area X2 is covered by the viewing angle of the reflecting surface b only. The scanning density of the Z area is the maximum, the resolution is the highest, and the resolutions of three field angles of a reflecting surface a, a reflecting surface b and a reflecting surface c are superposed; the Z Region can be detected as a Region of Interest (ROI). The resolution of the Y1 area is inferior to that of the Y2 area, the Y1 area is superimposed by the resolution of the two angles of view of the reflective surface a and the reflective surface c, and the resolution of the Y2 area is superimposed by the resolution of the two angles of view of the reflective surface a and the reflective surface b. The resolution of the X1 region and the X2 region is the lowest, the resolution of the X1 region is the resolution of the angle of view formed by the reflection surface c, and the resolution of the X2 region is the resolution of the angle of view formed by the reflection surface b.

In order to simplify the drawings and facilitate understanding of the above schemes, only the optical axis of the outgoing laser is shown in the above optical path diagrams, it can be understood that the outgoing laser itself has an emission angle with a certain emission range, and the outgoing laser which is incident to the rotating mirror 21 and is emitted has a certain spot diameter.

As shown in fig. 3, since the rotating mirror 21 needs to rotate around the rotating shaft 25, the spectroscopic plate 40 includes a fixed spectroscopic plate 41 and a rotating spectroscopic plate 42, and the rotating spectroscopic plate 42 is fixed to the rotating mirror 21 and rotates with the rotating mirror 21. The fixed light splitting plate 41 is provided with a through hole 43, and the rotating light splitting plate 42 is arranged in the through hole 43 and can rotate in the through hole 43. Can effectively reduce the space between rotatable parts and the fixed part, rotate the spectrometer 42 and change mirror 21 fixed, rotate the outer edge of spectrometer 42 and cooperate with the through-hole 43 shape of fixed spectrometer 41, the space is little, and effective separation outgoing laser and reflection laser avoid mutual crosstalk.

As shown in fig. 16, the laser radar 100 further includes a mirror module 50, and the mirror module 50 is fixed to the fixed beam splitter 41. The mirror module 50 includes a first mirror 51 and a second mirror 52; the first reflector 51 is disposed on the light path of the outgoing laser emitted by the emission module 10 and located on the first side of the beam splitter 40, and is configured to reflect the outgoing laser to the first reflector 211; the second reflecting mirror 52 is disposed on the light path of the echo laser reflected by the second rotating mirror 212 and located on the second side of the beam splitter 40, for reflecting the echo laser to the receiving module 30.

The first mirror 51 and the second mirror 52 may be integrally provided as one mirror, that is, they are of an integral structure, and the mirror is divided into two parts based on the beam splitter 40; the first mirror 51 and the second mirror 52 may also be provided as two separate mirrors. When the first mirror 51 and the second mirror are two separate mirrors, the first mirror 51 and the second mirror 52 are both fixed to the fixed splitting plate 41 and are disposed coplanar. The mirror module 50 may be a plane mirror, a cylindrical mirror, an aspherical curvature mirror, or the like.

The emergent laser emitted by the emitting module 10 is reflected by the reflector module 50 and then enters the scanning module 20, the mirror is reflected by the scanning module 20 and then emitted to the detection area, the echo laser is obtained after being reflected by an object in the detection area, the echo laser is emitted to the reflector module 50 after being reflected by the scanning module 20, and then enters the receiving module 30 after being reflected by the reflector module 50, and finally the echo laser is received by the receiving module 30. The light path of the emergent laser and the light path of the echo laser are folded through the reflector module 50, so that the arrangement among all devices is more compact, and the miniaturization of the laser radar 100 system is facilitated; the directions of the emergent laser and the echo laser are adjusted through the reflector module 50, so that the emergent laser is aligned to the better position of the scanning module 20, the echo laser is aligned to the receiving module 30, the light modulation is convenient, and the operation is simple.

As shown in fig. 17, the emission module 10 includes a laser module 11, an emission driving module 12, and an emission optical module 13. The laser module 11 is used for emitting emergent laser; the emission driving module 12 is connected with the laser module 11 and is used for driving and controlling the laser module 11 to work; the emission optical module 13 is disposed on a light path of the emitted laser light emitted by the laser module 11, and is configured to collimate the emitted laser light. The emission optical module 13 may be an optical fiber and a spherical lens group, a single spherical lens group, a cylindrical lens group, or the like.

The scanning module 20 further includes a driving device 22 and a transmission device 23, the driving device 22 is provided with an output shaft 24, the output shaft 24 is connected with the rotating mirror 21 through the transmission device 23, and the output shaft 24 of the driving device 22 drives the rotating mirror 21 to rotate. The driving device 22 may be a motor, and the transmission device 23 may be a transmission chain, a transmission gear, a transmission belt, or the like, which can implement power transmission; the output end of the driving device 22 can also directly drive the scanning module 20.

The receiving module 30 includes a detector module 31, a receiving driving module 32, and a receiving optical module 33. The receiving optical module 33 is disposed on the optical path of the echo laser reflected by the scanning module 20, and is configured to converge the echo laser; the detector module 31 is used for receiving the echo laser light converged by the receiving optical module 33; the receiving driving module 32 is connected to the detector module 31 for driving and controlling the detector module 31 to operate. The receiving optical module 33 may employ a ball lens, a ball lens group, or a cylindrical lens group, etc.

In addition, the laser radar 100 may further include a control and signal processing module (not shown), such as a Field Programmable Gate Array (FPGA), the FPGA and the emission driving module 12, for performing emission control of the emitted laser. The FPGA is also connected to a clock pin, a data pin, and a control pin of the receive driving module 32, respectively, to perform receive control of the echo laser.

The laser module 11 adopts a laser linear array, the detector module 31 adopts a detector linear array, and the laser radar 100 forms a vertical field angle covering a certain angle range to realize detection in the vertical direction.

As shown in fig. 18 and 19, in some embodiments, the plurality of lasers of the laser line array are arranged at the focal plane of the transmitting optical module 13, and the optical axes of the lasers pass through the center of the transmitting optical module 13, and the outgoing laser light passing through the transmitting optical module 13 covers a certain angular range of field angles.

If the interval between each laser in the laser linear array is set to be very small, when the outgoing laser passes through the transmitting optical module 13 and then is emitted outwards, the outgoing laser can be regarded as being continuously angle-changed within the range of the vertical field angle, and the laser linear array is located at the focal plane of the transmitting optical module. If the spacing between each laser in the laser linear array is not small enough, that is, if the spacing between each laser in the laser linear array is large, the laser linear array is not located at the focal plane of the transmitting optical module 13, so that each beam of outgoing laser has a certain divergence angle after passing through the transmitting optical module, and the divergence angle covers the gap between the outgoing laser caused by the spacing between the lasers, thereby avoiding discontinuous angle change of the outgoing laser in the vertical field range.

As shown in fig. 21, the emission optical module 13 may be a telecentric lens for collimating each outgoing laser light emitted from the laser module 11, respectively, and deflecting the outgoing laser light toward a central optical axis of the telecentric lens. Because a plurality of lasers of the laser linear array are arranged in a consistent manner, the directions of a plurality of emergent lasers are the same, and the emergent lasers can only cover a very small angle range in the vertical direction after being collimated, so that the detection requirement cannot be met. The telecentric lens deflects a plurality of parallel emergent laser beams to the central optical axis, and the emergent laser beams can cover a certain angle range in the vertical direction when being emitted outwards, namely, the emergent laser beams have a larger vertical field angle.

As shown in fig. 18 and 20, in some embodiments, the plurality of detectors of the detector array are arranged at the focal plane of the receiving optical module 33, and the optical axes of the detectors pass through the center of the receiving optical module 33, and the echo laser light passing through the receiving optical module 33 is received by the plurality of detectors.

In some embodiments, the plurality of detectors of the detector linear array may also be arranged on the plane where the focal point of the receiving optical module 33 is located, or near the plane where the focal point is located; the incident direction of the echo laser is inconsistent with the optical axis of the detector, so that the echo laser cannot vertically enter the detector, and the receiving efficiency of the detector on the echo laser is reduced; however, the arrangement may be adopted as long as the echo laser received by the detector linear array can meet the detection requirement.

The receiving optical module 33 may be a common focusing lens, and focuses the received echo laser beam to the receiving module 30; a telecentric lens can be arranged as the receiving optical module 23, and is used for converging the echo laser light and making each echo laser light incident perpendicular to the detector linear array (as shown in fig. 22); the receiving efficiency of the detector linear array is improved, and the detection effect of the laser radar 100 can be effectively improved.

The receiving angle of view of the receiving optical module needs to be the same as the emitting angle of view of the emitting optical module 13, and the following relationships are generally considered:

the system comprises a linear array of lasers, detectors, a receiving optical module, a detector, a receiving optical module and a transmitting optical module, wherein L is the distance between the lasers at the upper end and the lower end of the linear array of the lasers and is related to the number and the size of the intervals of the lasers, F is the focal length of the transmitting optical module, L 'is the distance between the detectors at the upper end and the lower end of the linear array of the detector and is related to the number and the size of the intervals of the detectors, F' is the focal length of the receiving.

The Laser linear array may adopt Laser Diode (LD) array, Vertical Cavity Surface Emitting Laser (VCSEL) array, fiber array, etc. to form a linear array light Emitting device. The detector linear array may adopt Avalanche Photodiode (APD) array, Silicon photomultiplier (SIPM), APD array, Multi-Pixel Photon Counter (MPPC) array, photomultiplier tube (PMT) array, single-Photon Avalanche Diode (SPAD) array, and the like, which may constitute a linear array receiving device.

In some embodiments, the arrangement of the laser linear arrays is sparse at two ends and dense in the middle, the arrangement of the detector linear arrays is sparse at two ends and dense in the middle, sparse-dense-sparse scanning in the vertical direction of the field of view can be realized, the resolution of the middle area is larger than that of the areas at two ends, and the detection requirement that the information of the middle area is more concerned in the detection process is met.

The number of detectors included in the detector linear array is not equal to the number of lasers included in the laser linear array, but the emitted laser needs to ensure that enough light energy can be responded by the detectors in the corresponding field angle of each detector in the detector linear array. The number of detectors included in the detector array determines the resolution of laser radar 100 in the vertical direction. The number of detectors contained in the detector linear arrays can be larger than or equal to the number of lasers contained in the laser linear arrays. In an alternative embodiment, the laser module 11 includes a lasers arranged along a linear array, where a is an integer and a is greater than or equal to 1, the detector module 31 includes k × a detectors arranged along the linear array, each laser corresponds to k detectors, where a is an integer and a is greater than or equal to 1, and k is an integer and k is greater than or equal to 1; i.e. the number of detectors and the number of lasers are integer multiples. For example 1 laser for 1 detector or 1 laser for 4 detectors. In another alternative embodiment, the number of detectors and the number of lasers may not be integer multiples. For example, a laser line array includes 4 lasers and a detector line array includes 6 detectors.

Further, based on the laser radar 100, the embodiment of the present invention provides an autopilot device 200 including the laser radar 100 in the above embodiment, where the autopilot device 200 may be an automobile, an airplane, a ship, or other devices related to intelligent sensing and detection using the laser radar 100, the autopilot device 200 includes a device body 201 and the laser radar 100 in the above embodiment, and the laser radar 100 is mounted on the device body 201.

As shown in fig. 23, the autonomous driving apparatus 200 is an unmanned automobile, and the laser radar 100 is mounted on a side surface of the automobile body. As shown in fig. 24, the autonomous driving apparatus 200 is also an unmanned automobile, and the laser radar 100 is mounted on the roof of the automobile.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention, and they should be construed as being included in the following claims and description. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. It is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

Lidar (100) characterized in that the lidar (100) comprises a transmitting module (10), a scanning module (20) and a receiving module (30);

the emission module (10) is used for emitting emergent laser;

the scanning module (20) comprises a rotating mirror (21) rotating around a rotating shaft (25), wherein the rotating mirror (21) is used for receiving the emergent laser and reflecting the emergent laser to emit to a detection area, and is also used for receiving echo laser and reflecting the echo laser to emit to the receiving module (30); the echo laser is returned after the emergent laser is reflected by an object in the detection area;

the receiving module (30) is arranged on the other side of the transmitting module (10) along the direction of the rotating shaft (25) and is used for receiving the echo laser.
Lidar (100) according to claim 1, wherein said rotating mirror (21) is a flat mirror (21 a).
The lidar (100) of claim 2, wherein an angle δ between the rotational axis (25) and the planar mirror (21a) is 0 ° δ < 90 °.
Lidar (100) according to claim 1, wherein said rotating mirror (21) is a polygonal mirror, each outer side of said polygonal mirror being a reflecting surface.
The lidar (100) of claim 4, wherein said outgoing laser light and said corresponding said return laser light are reflected from a same said reflective surface of said polygon at any time.
Lidar (100) according to claim 4 or 5, wherein at least one of said reflecting surfaces of said polygon has a different angle to said rotation axis (25) than the other of said reflecting surfaces.
Lidar (100) according to claim 4 or 5, wherein said reflecting surfaces of said polygon mirror are all at the same angle to said rotation axis (25).
The lidar (100) of claim 1, wherein the lidar (100) further comprises a beamsplitter (40) for isolating the outgoing laser light and the return laser light.
Lidar (100) according to claim 8, wherein said beamsplitter (40) comprises a fixed beamsplitter (41), said fixed beamsplitter (41) being arranged between said transmitting module (10) and said receiving module (30).
The lidar (100) of claim 9, wherein the beam splitter (40) further comprises a rotating beam splitter (42), the rotating beam splitter (42) is fixed to the rotating mirror (21) and rotates with the rotating mirror (21), the fixed beam splitter (41) has a through hole (43) formed therein, and the rotating beam splitter (42) is disposed in the through hole (43).
The lidar (100) of claim 1, wherein the lidar (100) further comprises a mirror module (50), the mirror module (50) comprising a first mirror (51) and a second mirror (52);

the first reflector (51) is arranged on a light path of the emergent laser emitted by the emission module (10) and used for reflecting the emergent laser to the first rotating mirror (211);

the second reflecting mirror (52) is arranged on a light path of the echo laser reflected by the second rotating mirror (212) and used for reflecting the echo laser to the receiving module (30).
Lidar (100) according to claim 1, wherein said transmit module (10) comprises a laser module (11), a transmit drive module (12) and a transmit optical module (13);

the laser module (11) is used for emitting emergent laser;

the emission driving module (12) is connected with the laser module (11) and is used for driving and controlling the laser module (11) to work;

the emission optical module (13) is arranged on a light path of the emergent laser emitted by the laser module (11) and is used for collimating the emergent laser.
Lidar (100) according to claim 12, wherein said laser module (11) is a linear laser array comprising a lasers, wherein a is an integer and a ≧ 1, said linear laser array being arranged in the direction of said rotation axis (25).
Lidar of claim 12, wherein said transmit optical module (13) is a telecentric lens for collimating and deflecting each of said outgoing laser beams emitted by said laser module (11) towards a central optical axis of said telecentric lens, respectively.
The lidar (100) of claim 1, wherein said scanning module (20) further comprises a driving device (22) and a transmission device (23), said driving device (22) being provided with an output shaft (24), said output shaft (24) being connected to said turning mirror (21) through said transmission device (23), said output shaft (24) of said driving device (22) driving said turning mirror (21) to turn.
Lidar (100) according to claim 113, wherein said receive module (30) comprises a detector module (31), a receive drive module (32), and a receive optics module (33);

the receiving optical module (33) is arranged on a light path of the echo laser reflected by the scanning module (20) and is used for converging the echo laser;

the detector module (31) is used for receiving the echo laser light converged by the receiving optical module (33);

the receiving driving module (32) is connected with the detector module (31) and is used for driving and controlling the detector module (31) to work.
The lidar (100) of claim 16, wherein said detector module (31) is a linear detector array comprising k x a detectors, wherein a is an integer and a ≧ 1, k is an integer and k ≧ 1, each said laser corresponds to k said detectors, said linear detector array disposed along said axis of rotation (25).
Lidar according to claim 16, wherein said receiving optics (33) is a telecentric lens for converging said echo laser light and making each of said echo laser light incident perpendicular to said detector bars.
An autopilot device (200) comprising a device body (201) and a lidar (100) of any of claims 1 to 18, the lidar (100) being mounted to the device body (201).