CN117784090A

CN117784090A - Laser radar device

Info

Publication number: CN117784090A
Application number: CN202311796803.8A
Authority: CN
Inventors: 胡锦铭; 刘岳飞
Original assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Current assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Priority date: 2023-12-25
Filing date: 2023-12-25
Publication date: 2024-03-29

Abstract

The embodiment of the invention discloses a laser radar device, which comprises: the system comprises an emission system and a receiving system, wherein the emission system comprises a light source array, a lens group, a first plane reflecting mirror and a three-side rotating mirror which are sequentially arranged; the receiving system comprises an imaging lens group, a second plane reflecting mirror and a detection receiver, wherein the imaging lens group comprises a first imaging lens, a second imaging lens and a third imaging lens which are sequentially arranged; the second planar mirror is disposed between the first imaging lens and the second imaging lens; the lens group and the imaging lens group are made of glass. The device provided by the embodiment of the invention can realize smaller overall volume of the laser radar, and can meet the high-temperature environment and volume limiting conditions of the automobile.

Description

Laser radar device

Technical Field

The invention relates to the technical field of laser radars, in particular to a laser radar device.

Background

In recent years, with the great development of intelligent driving, new energy and other technologies, automobiles have moved from traditional fuel oil walking tools to more intelligent. The laser radar is used as the latest intelligent driving sensor, is equivalent to the 'eyes' of an automobile, and has wide application prospect. The laser has the advantages of concentrated energy, good directivity and monochromaticity, etc. Compared with a camera and a millimeter wave radar, the laser radar can detect farther distances, has higher precision, and can also realize point cloud images, thereby realizing higher-order auxiliary driving.

At present, vehicle-mounted laser radars are mainly classified into mechanical laser radars, semi-solid laser radars and all-solid laser radars. The mechanical laser radar has the advantages of high scanning speed, small receiving view field, strong light interference resistance, high signal to noise ratio and the like, but has the advantages of higher cost, more complex light path debugging and assembly, long production period and low reliability in a driving environment. The all-solid-state laser radar has no swinging firmware, can realize accurate local scanning, has small volume and better performance, but has high requirements on processing, equipment and debugging of parts, has very large production difficulty, and is not completely mature in the current production technology. The semi-solid laser radar is a mainstream product on the vehicle at present, and has the advantages of relatively compact structure, relatively low cost and relatively convenient production and assembly. And the vehicle-mounted environment of the automobile is severe, and volume limitation, high temperature resistance and the like are always key problems in the application of the vehicle-mounted laser radar. However, the existing semi-solid laser radar cannot meet the high-temperature environment and the volume limitation condition of the automobile.

Therefore, it is necessary to design a new device to realize a smaller overall volume of the lidar and to meet the high temperature environment and volume constraints of the car.

Disclosure of Invention

The invention aims to provide a laser radar device.

In order to solve the technical problems, the aim of the invention is realized by the following technical scheme: provided is a laser radar device including: the system comprises an emission system and a receiving system, wherein the emission system comprises a light source array, a lens group, a first plane reflecting mirror and a three-side rotating mirror which are sequentially arranged; the receiving system comprises an imaging lens group, a second plane reflecting mirror and a detection receiver, wherein the imaging lens group comprises a first imaging lens, a second imaging lens and a third imaging lens which are sequentially arranged; the second planar mirror is disposed between the first imaging lens and the second imaging lens; the lens group and the imaging lens group are made of glass.

The further technical scheme is as follows: the three-sided rotating mirror is positioned below the first plane reflecting mirror.

The further technical scheme is as follows: the lens group comprises a first collimating lens, a second collimating lens and a third collimating lens which are sequentially arranged; a first plane emission mirror is arranged between the second collimating lens and the third collimating lens.

The further technical scheme is as follows: the first plane reflecting mirror is provided with a first reflecting surface, and the first reflecting surface is plated with an enhanced reflecting film; the first plane reflecting mirror is provided with a second reflecting surface, and the second reflecting surface is plated with an enhanced reflecting film and an anti-reflection film; the three-sided rotating mirror is provided with a third reflecting surface, and the third reflecting surface is plated with an enhanced reflecting film.

The further technical scheme is as follows: the first imaging lens, the second imaging lens and the third imaging lens are respectively plated with an antireflection film; the second plane reflector is provided with a fourth reflecting surface, and the fourth reflecting surface is plated with an enhanced reflecting film.

The further technical scheme is as follows: the light source array comprises a plurality of four rows of solid lasers which are arranged in a staggered manner.

The further technical scheme is as follows: the effective focal length of the emission system meets the condition of 80mm < EFL <120mm; the total length TTL of the receiving system meets the condition that TTL is 40mm < 100mm.

The further technical scheme is as follows: the total length of the receiving system meets the condition that TTL is 40mm < 100mm, and the effective focal length of the receiving system meets the condition that EFL is 30mm <80mm.

The further technical scheme is as follows: the entrance pupil diameter of the receiving system is 40mm < ENPD <80mm.

The further technical scheme is as follows: the diameter of the spot of the incident laser of the receiving system is smaller than the radius of the detection receiver.

Compared with the prior art, the invention has the beneficial effects that: according to the invention, the emission system and the receiving system are arranged, wherein the emission system adopts a light source array as a laser emission structure, and a three-sided rotating mirror is combined, so that the performance of the vehicle-mounted laser radar is improved, the hundred-meter detection of the laser radar is solved, and a point cloud picture is realized; the lens group arranged by adopting high-temperature-resistant glass forms one part of the emission system and the receiving system, so that the problem of stability of the high-temperature-resistant material is solved; and the mode of two pairs of light source arrays and detection receivers is adopted, so that the number of receiving devices is reduced, the cost is reduced, the processing difficulty is reduced, the overall size of the laser radar is smaller, and the environment and the volume limiting condition of the high temperature of the automobile can be met.

The invention is further described below with reference to the drawings and specific embodiments.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a lidar device according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a light source array according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a detection receiver according to an embodiment of the present invention;

the figure identifies the description:

1. an array of light sources; 2. a first collimating lens; 3. a second collimating lens; 4. a first planar emission mirror; 5. a third collimating lens; 6. a first planar mirror; 7. three-sided turning mirror; 8. a first imaging lens; 9. a second planar mirror; 10. a second imaging lens; 11. a third imaging lens; 12. the receiver is probed.

Detailed Description

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

It should be understood that the terms "comprises" and "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this specification and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a laser radar device according to an embodiment of the present invention, where the device may be applied in a scene where a laser radar is needed, such as an automobile, to achieve a smaller overall volume of the laser radar, and may satisfy the high-temperature environment and the volume limitation conditions of the automobile.

Referring to fig. 1, the laser radar apparatus includes: the system comprises an emission system and a receiving system, wherein the emission system comprises a light source array 1, a lens group, a first plane mirror 6 and a three-side rotating mirror 7 which are sequentially arranged; the receiving system comprises an imaging lens group, a second plane reflecting mirror 9 and a detection receiver 12, wherein the imaging lens group comprises a first imaging lens 8, a second imaging lens 10 and a third imaging lens 11 which are sequentially arranged; the second plane mirror 9 is disposed between the first imaging lens 8 and the second imaging lens 10; the lens group and the imaging lens group are made of glass.

In this embodiment, as shown in fig. 2, the light source array 1 includes a plurality of four rows of regularly arranged solid lasers that are offset from each other. Specifically, the emission system adopts 128 solid lasers, and the laser adopts 905nm wavelength; the four rows of the laser light sources are arranged in a staggered manner, 128 lines are shared by the laser light sources, and the laser light sources are combined with an optical lens system to realize higher vertical reflection angle precision.

As shown in fig. 3, the detection receiver 12 is composed of 64 photosensitive chips, and the layout arrangement of the detection receiver is matched with the emission light source; the layout arrangement of the light source array is matched with the light source array 1, so that the corresponding distribution of '2 to 1' can be realized, and the light receiving efficiency is higher.

In addition, the lens of the transmitting and receiving system is made of glass, and is partially cut so as to reduce the volume of the lens and be suitable for the assembly and adjustment of the whole structure, and meanwhile, the lens is made of glass and has good stability, so that the temperature drift phenomenon brought to the system by temperature change can be reduced on a vehicle.

In one embodiment, referring to fig. 1, the three-sided turning mirror 7 is located below the first plane mirror 6.

In an embodiment, referring to fig. 1, the lens assembly includes a first collimating lens 2, a second collimating lens 3, and a third collimating lens 5 sequentially arranged; a first plane emitter mirror 4 is arranged between the second collimating lens 3 and the third collimating lens 5.

In an embodiment, referring to fig. 1, the first plane mirror 4 is provided with a first reflective surface, and the first reflective surface is coated with an enhanced reflective film; the first plane reflector 6 is provided with a second reflecting surface, and the second reflecting surface is plated with an enhanced reflecting film; the three-sided rotating mirror 7 is provided with a third reflective surface which is plated with an enhanced reflective film.

In an embodiment, referring to fig. 1, the first imaging lens 8, the second imaging lens 10 and the third imaging lens 11 are respectively coated with an antireflection film; the second plane mirror 9 is provided with a fourth reflecting surface which is coated with an enhanced reflecting film.

In the present embodiment, the first reflection surface of the first plane mirror 4 is plated with a 905nm enhanced reflection film; the first plane reflector 6 is a plane reflector with a special structure, and adopts a partition coating mode, wherein a 905nm antireflection film is coated on the surface of the first plane reflector 6, and a 905nm enhancement reflection film is coated on the surface of the first plane reflector; the surface of the three-side rotating mirror 7 which rotates rapidly is plated with a 905nm enhanced reflecting film, and when the rotating mirror rotates rapidly, the emergent light beam scans horizontally; the optical distortion of the emission system is small, the laser divergence angle of the maximum field of view is small, and more than 90% of laser energy can be collected on the measured object.

The optical lens group consisting of the first imaging lens 8, the second imaging lens 10 and the third imaging lens 11 realizes the imaging function of the receiving system, so that the received laser is imaged on the laser detector, and the surfaces of the optical lens group are plated with 905nm antireflection films; the second plane reflecting mirror 9 realizes the deflection of the light path by 90 degrees, and the reflecting surface is plated with a 905nm enhanced reflecting film.

In this embodiment, the first imaging lens 8 is located above the first plane mirror 6, the second plane mirror 9 is located above the first imaging lens 8, and the first collimating lens 2, the second collimating lens 3 and the light source array 1 are coaxially and longitudinally arranged; the first imaging lens 8, the second imaging lens 10, and the third imaging lens 11 are coaxially and laterally arranged.

In an embodiment, the effective focal length of the emission system is 80mm < EFL <120mm; the total length TTL of the receiving system meets the condition that TTL is 40mm < 100mm. The optical distortion of the emission system is less than 4.5%, the maximum field laser divergence angle theta is less than 1.6mrad, and more than 90% of laser energy is collected on the measured object when the maximum field laser divergence angle theta is more than 1.3 mrad.

In an embodiment, the total length of the receiving system satisfies the condition that 40mm < TTL < 100mm, and the effective focal length of the receiving system satisfies the condition that 30mm < EFL <80mm.

In an embodiment, the entrance pupil diameter of the receiving system is 40mm < enpd <80mm.

In one embodiment, the spot diameter of the incident laser light of the receiving system is smaller than the radius of the detection receiver 12.

The optical distortion of the receiving system is less than 4.5%.

In this embodiment, the lenses of the transmitting system and the receiving system are made of glass, the abbe numbers Vd >20, and the lenses are partially cut and rectangular in caliber, so that the volume of the lenses is reduced, the lenses are suitable for assembly and adjustment of an integral structure, and meanwhile, the lenses are made of glass and have good stability, so that temperature drift phenomenon caused by temperature change on a vehicle can be reduced. The whole system can realize larger field laser detection.

The horizontal scanning of the target is realized by utilizing the array of the laser and adding the three-sided rotating mirror 7, the high-precision angle resolution of the laser radar is realized by combining a transmitting and receiving system, and finally, the point cloud picture is realized, and the detection distance of hundred meters is reached.

The emitting system adopts 128 solid lasers and 64 receivers, the cost of components is effectively reduced through the structural layout of '2 to 1', high-resolution scanning of 128 lines in the vertical direction is realized, and a three-dimensional point cloud picture can be realized by combining a rotating mirror.

Referring to fig. 2, the light source array 1 uses 128 solid lasers in total, adopts the laser light source layout shown in fig. 2, the vertical interval of the solid lasers is determined by the size of the lasers and the interval of the patches, the vertical scanning angle difference corresponding to the adjacent lasers is 0.4 °, and the scanning resolution of 0.2 ° and the vertical scanning field of view of 25.4 ° are realized through the column-to-column dislocation distribution. The laser beam reflected by the target should be accurately focused on the corresponding position of the receiver, and according to the beam emergent angle of the transmitting system, the receivers are closely arranged in the vertical and horizontal directions by combining the light sensitive area of the receiver and the patch interval of the adjacent receivers, so as to obtain an arrangement and combination scheme of 64 receivers, and as shown in fig. 3, the arrangement and combination scheme forms a corresponding relation of '2 to 1' with 128 solid lasers at the transmitting end.

The transmitting system and the receiving system of the laser radar device are matched with each other, so that the transmitting devices and the receiving devices can be distributed at equal intervals, and the processing difficulty of a PCB is reduced; the emission system can realize the high collimation of laser beams, the beam separation between points is clear, and the angle distribution of each point is accurate; the receiving system is matched with the transmitting system, and the photosensitive surface of the receiver can accurately detect the corresponding transmitting light spots so as to establish accurate space point cloud distribution; the plane scanning is realized, the whole volume of the laser radar is reduced, and the effects of compact whole structure and long-time stable work are achieved; in the embodiment, the optical system used adopts high-temperature-resistant spherical glass lenses, so that the difficulty and cost are reduced. The lens is cut according to the effective light-transmitting aperture of the lens, so that the whole volume of the laser radar transmitting device is further reduced; specifically, according to the effective clear aperture on the lens, rectangular cuts are made on the first collimating lens 2, the second collimating lens 3, the third collimating lens 5, the first imaging lens 8, the second imaging lens 10, and the third imaging lens 11, so as to further reduce the overall volume of the laser spot emitting apparatus.

According to the laser radar device, the transmitting system and the receiving system are arranged, wherein the transmitting system adopts the light source array 1 as a laser transmitting structure, and the three-face turning mirror 7 is combined, so that the performance of the vehicle-mounted laser radar is improved, the hundred-meter detection of the laser radar is solved, and the point cloud picture is realized; the lens group arranged by adopting high-temperature-resistant glass forms one part of the emission system and the receiving system, so that the problem of stability of the high-temperature-resistant material is solved; and the mode of two pairs of the light source array 1 and the detection receiver 12 is adopted, so that the number of receiving devices is reduced, the cost is reduced, the processing difficulty is reduced, the overall size of the laser radar is smaller, and the environment and the volume limiting condition of the high temperature of the automobile can be met.

While the invention has been described with reference to certain preferred embodiments, it will be understood by those skilled in the art that various changes and substitutions of equivalents may be made and equivalents will be apparent to those skilled in the art without departing from the scope of the invention. Therefore, the protection scope of the invention is subject to the protection scope of the claims.

Claims

1. A lidar device, comprising: the system comprises an emission system and a receiving system, wherein the emission system comprises a light source array, a lens group, a first plane reflecting mirror and a three-side rotating mirror which are sequentially arranged; the receiving system comprises an imaging lens group, a second plane reflecting mirror and a detection receiver, wherein the imaging lens group comprises a first imaging lens, a second imaging lens and a third imaging lens which are sequentially arranged; the second planar mirror is disposed between the first imaging lens and the second imaging lens; the lens group and the imaging lens group are made of glass.

2. The lidar device according to claim 1, wherein the three-sided turning mirror is located below the first plane mirror.

3. The lidar device according to claim 1, wherein the lens group comprises a first collimating lens, a second collimating lens, and a third collimating lens arranged in this order; a first plane emission mirror is arranged between the second collimating lens and the third collimating lens.

4. A lidar device according to claim 3, wherein the first plane mirror is provided with a first reflection surface, and the first reflection surface is coated with an enhanced reflection film; the first plane reflecting mirror is provided with a second reflecting surface, and the second reflecting surface is plated with an enhanced reflecting film and an anti-reflection film; the three-sided rotating mirror is provided with a third reflecting surface, and the third reflecting surface is plated with an enhanced reflecting film.

5. The lidar device according to claim 4, wherein the first imaging lens, the second imaging lens, and the third imaging lens are each coated with an antireflection film; the second plane reflector is provided with a fourth reflecting surface, and the fourth reflecting surface is plated with an enhanced reflecting film.

6. A lidar device according to claim 1, wherein the array of light sources comprises a plurality of four rows of regularly arranged solid state lasers that are offset from each other.

7. A lidar device according to claim 1, wherein the effective focal length of the transmitting system fulfils the condition 80mm < efl <120mm; the total length TTL of the receiving system meets the condition that TTL is 40mm < 100mm.

8. A lidar device according to claim 1, wherein the total length of the receiving system fulfils the condition 40mm < TTL < 100mm, and the effective focal length of the receiving system fulfils the condition 30mm < efl <80mm.

9. A lidar device according to claim 1, wherein the entrance pupil diameter of the receiving system is 40mm < enpd <80mm.

10. A lidar device according to claim 1, wherein the spot diameter of the incident laser light of the receiving system is smaller than the radius of the detection receiver.