CN218917764U

CN218917764U - Reflecting mirror assembly, laser emission module and laser radar

Info

Publication number: CN218917764U
Application number: CN202223207759.6U
Authority: CN
Inventors: 张楠; 徐洪涛; 孟宪东; 刘佳尧; 石拓
Original assignee: Zvision Technologies Co Ltd
Current assignee: Zvision Technologies Co Ltd
Priority date: 2022-11-30
Filing date: 2022-11-30
Publication date: 2023-04-25
Anticipated expiration: 2032-11-30

Abstract

The application provides a speculum subassembly, laser emission module and laser radar, wherein, the speculum subassembly includes: the hemispherical mounting seat is provided with a first surface and a second surface, the first surface is a hemispherical convex surface, and the second surface is opposite to the first surface; a reflector holder having at least one hemispherical concave surface, one hemispherical concave surface conforming to at least a portion of one hemispherical convex surface; the circular reflector is fixed on the second surface and is used for reflecting the incident laser beam; the second surface is at least used for being planar with the circular reflector fixing area, and the edges of the circular reflector and the second surface are flush. In the speculum subassembly of this application, through fixing circular speculum on the hemisphere mount pad, the edge of circular speculum can not surpass the edge of second surface or surpass too much to can with the better laminating of the second surface of hemisphere mount pad, reduce the speculum and drop or appear warp the probability of deformation from the mount pad.

Description

Reflecting mirror assembly, laser emission module and laser radar

Technical Field

The application relates to the technical field of laser radars, in particular to a reflecting mirror assembly, a laser emission module and a laser radar.

Background

The laser radar comprises a laser emitting module, a laser receiving module and a processor for processing echo beams received by the laser receiving module.

The laser emission module comprises a reflecting mirror component, wherein the reflecting mirror component can change the light path of a laser beam emitted by the laser, so that the laser beam can be emitted from the laser emission module according to a preset angle.

However, with the increase of the service time of the laser radar, the reflector in the reflector module is easy to generate problems of buckling deformation, cracking, falling off from the mounting seat, and the like, so that the reflection of the reflector on the laser beam is affected.

Disclosure of Invention

The embodiment of the application provides a reflector assembly, laser emission module and laser radar, can reduce the reflector and drop or appear warp the probability of deformation from the mount pad.

In a first aspect, the present application provides a mirror assembly comprising:

the hemispherical mounting seat is provided with a first surface and a second surface, the first surface is a hemispherical convex surface, and the second surface is opposite to the first surface;

a reflector holder having at least one hemispherical concave surface, one of said hemispherical concave surfaces conforming to at least a portion of one of said hemispherical convex surfaces;

The circular reflector is fixed on the second surface and is used for reflecting the incident laser beam; wherein, the area of the second surface at least for fixing with the circular reflector is a plane, and the edges of the circular reflector and the second surface are flush.

Optionally, the hemispherical convex surface and the hemispherical concave surface are bonded by an adhesive.

Optionally, the hemispherical convex surface has one or more first grooves protruding toward the second surface;

the hemispherical concave surface is provided with one or more through holes;

the first groove is filled with adhesive injected through the through hole;

the adhesive adheres the hemispherical mount and the mirror support.

Optionally, the through hole is disposed near the center of the hemispherical concave surface.

Optionally, the mirror support includes:

a body portion having a plurality of mounting areas, one of said mounting areas having one of said hemispherical concave surfaces therein, and a land area located around said hemispherical concave surface; the included angle of the plane where the platform areas of the adjacent installation areas are located is an obtuse angle;

and a connection part connected to both ends of the body part.

Optionally, the connecting portion includes: a first connection portion and a second connection portion;

the first connecting parts are connected to two ends of the main body part and extend to the opening side of the hemispherical concave surface along the thickness direction of the main body part;

the second connecting portion is connected to a side of the first connecting portion remote from the main body portion.

Optionally, the main body part has a first long side and a second long side which are oppositely arranged along the long axis direction;

the first connecting portion is gradually widened along the direction from the first long side to the second long side.

Optionally, the mirror support further has a stiffener;

the reinforcing plate is fixed in a space surrounded by the first connecting part and the second connecting part and is connected with the second long edge.

In a second aspect, an embodiment of the present application provides a laser emission module, including:

a housing;

a mirror assembly according to any preceding claim;

wherein the mirror assembly is mounted on the housing.

Optionally, the mirror assembly comprises a mirror support;

a first limit structure is arranged on the second connecting part of the reflector bracket;

the shell is provided with a second limiting structure matched with the first limiting structure;

The first limiting structure is matched with the second limiting structure and used for limiting the installation position of the reflector bracket on the shell.

Optionally, the first limiting structure is at least one limiting pin, and the second limiting structure is a limiting groove matched with the limiting pin;

or alternatively;

the first limit structure is at least one limit groove, and the second limit structure is a limit pin matched with the limit groove.

In a third aspect, embodiments of the present application provide a lidar, the lidar comprising:

a laser receiving module;

a processor;

and a laser emitting module according to any one of the above.

Compared with the prior art, the technical scheme provided by the embodiment of the application has the beneficial effects that:

in this application embodiment, because the mount pad of circular speculum is the hemisphere, consequently, the second surface of mount pad is circular, and when circular speculum was fixed on the hemisphere mount pad, the edge of circular speculum can not surpass the edge of second surface or surpass too much to can with the better laminating of the second surface of hemisphere mount pad, reduced the speculum because with the mount pad between not laminating lead to from the mount pad drop or the probability of warp deformation appears.

Drawings

FIG. 1 is an exploded view of a mirror assembly in an embodiment of the present application;

FIG. 2 is a schematic view of an assembled mirror assembly according to an embodiment of the present application;

FIG. 3 is a schematic view of a circular mirror and hemispherical mount according to an embodiment of the present application;

FIG. 4 is a schematic view of a mirror support according to an embodiment of the present application;

FIG. 5 is a schematic view of another hemispherical mount according to an embodiment of the present application;

FIG. 6 is a schematic view of another mirror support in an embodiment of the present application;

fig. 7 is a schematic structural diagram of a laser emitting module according to an embodiment of the present application;

FIG. 8 is an exploded view of a laser emitting module according to an embodiment of the present application;

FIG. 9 is a graph of test results of test 1 provided in the examples of the present application;

FIG. 10 is a graph of test results of test 2 provided in the examples of the present application;

FIG. 11 is a graph of test results of test 3 provided in the examples of the present application;

FIG. 12 is a graph of test results of test 4 provided in the examples of the present application;

FIG. 13 is a graph of test results of test 5 provided in the examples of the present application;

FIG. 14 is a graph of test results of test 6 provided in the examples of the present application;

FIG. 15 is a graph of test results of test 7 provided in the examples of the present application;

Fig. 16 is a graph of test results of test 8 provided in the examples of the present application.

Reference numerals illustrate:

1. a hemispherical mounting seat 11, a first surface 12, a second surface 13 and a first groove;

2. the reflector bracket, 21, hemispherical concave surface, 211, mounting hole, 22, through hole, 221, first opening, 222, second opening, 23, main body part, 231, first long side, 232, second long side, 24, connecting part, 241, limit pin, 242, first connecting part, 243, second connecting part, 25, first bolt hole;

3. a circular reflector, 31, a reflecting surface, 32, a connecting surface;

4. the housing 41, the laser channel 42, the limit groove 43, the second bolt hole 44 and the third surface.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system configurations, techniques, etc. in order to provide a thorough understanding of embodiments of the present utility model. It will be apparent, however, to one skilled in the art that the present utility model may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present utility model with unnecessary detail.

The terms "first," "second," and the like in the description and in the claims, are not used for any order, quantity, or importance, but are used for distinguishing between different elements. Also, the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one, and the terms "a" and "an" are used individually. "plurality" or "plurality" means two or more. Unless otherwise indicated, the terms "front," "rear," "lower," and/or "upper" and the like are merely for convenience of description and are not limited to one location or one spatial orientation. The word "comprising" or "comprises", and the like, means that elements or items appearing before "comprising" or "comprising" are encompassed by the element or item recited after "comprising" or "comprising" and equivalents thereof, and that other elements or items are not excluded.

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 also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

The laser radar is a device for acquiring information such as morphology, position, motion and the like of a measured target by actively scanning the measured target by emitting and receiving laser beams with specific wavelengths.

In an intelligent driving scene of an automobile, the laser radar is a main sensor for detecting the driving environment of the automobile, and can scan and measure the surrounding environment of the automobile, so that the detection precision and stability of the laser radar can have an important influence on the driving safety of the automobile, and the detection precision and stability of the laser radar are also required to be higher.

The laser radar comprises a laser emission module and a laser receiving module, wherein the laser emission module is mainly used for emitting laser beams, and the laser receiving module is mainly used for receiving echo beams of the laser beams after being reflected by a measured target. Because the laser radar has higher requirements on the emergent angle of the emergent laser beam, a reflecting mirror is arranged in the laser emission module to adjust the light path of the laser beam in general, so that the laser beam can be emitted along a preset angle after being reflected by the reflecting mirror and the corresponding MEMS scanning galvanometer.

It can be seen that the mirror is an important component in the laser emitting module. The reflector is fixed on the shell of the laser emission module through the reflector mounting seat and the reflector support, so that the mounting precision of the reflector on the mounting seat and the mounting precision of the mounting seat on the reflector support can influence the emergent angle of the laser beam, and further influence the detection precision of the laser radar.

In the related art, in order to reduce the volume of the laser radar and to miniaturize the laser radar, a thin glass material is generally used to manufacture the mirror, and an aluminum alloy material is used to manufacture the mirror and the mirror support, wherein the thermal expansion coefficient of the aluminum alloy material is 23.6ppm, and the thermal expansion coefficient of the glass material is 7.2ppm.

Based on this, when the temperature of the reflector and the reflecting seat is increased due to the heat generated by the operation of the laser radar, the deformation amount of the mounting seat is far greater than that of the reflector due to the large difference of the thermal expansion coefficients between the reflector and the mounting seat, and the mounting seat with large deformation amount is easy to tear the reflector with small deformation amount, or the reflector is easy to warp and deform, even fall off from the mounting seat and other problems are caused.

In addition, when the reflector bracket is made of an aluminum alloy material, in order to reduce the influence of the reflector bracket on the volume of the laser radar, the thickness of the reflector bracket is generally reduced. On the basis of this, when the temperature change range of the working environment is large, the mirror holder is deformed, and the position of the mirror fixed to the mirror holder is changed, thereby affecting the detection accuracy of the laser radar.

In order to solve the above problems, embodiments of the present application provide a mirror assembly, which specifically includes:

referring to fig. 1 to 4, a mirror assembly according to an embodiment of the present application includes:

a hemispherical mount 1, having a first surface 11 and a second surface 12, wherein the first surface 11 is a hemispherical convex surface, and the second surface 12 is disposed opposite to the first surface 11;

a mirror support 2 having at least one hemispherical concave surface 21, one of said hemispherical concave surfaces 21 being in abutment with at least part of one of said hemispherical convex surfaces;

a circular reflecting mirror 3 fixed on the second surface 12 for reflecting the incident laser beam; wherein at least the area of the second surface 12 for fixing with the circular mirror 3 is a plane, and the edges of the circular mirror 3 and the second surface 12 are flush.

The reflecting mirror assembly in the embodiment of the application can be used in a laser emission module of a laser radar and used for reflecting a laser beam emitted by a laser in the laser radar so as to change the light path of the laser beam in the laser emission module.

Illustratively, when a MEMS (Micro-Electro-Mechanical Systems, microelectromechanical system) component is provided in the laser emission module, the laser beam reflected by the mirror component may be incident on the mirror unit in the MEMS component, so that by adjusting the orientation of the mirror in the mirror component, the incident angle of the laser beam incident on the MEMS component may be adjusted, and thus the outgoing angle of the laser beam reflected by the mirror unit in the MEMS component may be adjusted.

The hemispherical mount 1 of the embodiment of the present application includes: a first surface 11 and a second surface 12; the first surface 11 is a first hemispherical convex surface; the second surface 12 is a circular plane.

The mirror bracket 2 has the same number of hemispherical concave surfaces 21 as the hemispherical mounts 1, and the curvature of each hemispherical concave surface 21 is substantially the same as the curvature of the hemispherical convex surface of each hemispherical mount 1, for example, the difference between the curvature of each hemispherical concave surface 21 and the curvature of the hemispherical convex surface of the hemispherical mount 1 is within a preset range. Based on this, when the hemispherical mount 1 is mounted in the hemispherical concave surface 21 of the mirror bracket 2, the hemispherical convex surface of the hemispherical mount 1 can be fitted with the hemispherical concave surface 21 of the mirror bracket 2.

It should be noted that, the hemispherical convex surface of the hemispherical mount 1 may be completely bonded to the hemispherical concave surface 21 of the reflector holder 2, or may be partially bonded to the hemispherical concave surface, that is, when the hemispherical mount 1 is fixed in the hemispherical concave surface 21, the hemispherical mount 1 may be completely embedded in the hemispherical concave surface 21, or may be partially embedded in the hemispherical concave surface 21.

The circular reflecting mirror 3 includes a reflecting surface 31 and is disposed on a connecting surface 32 opposite to the reflecting surface 31.

The reflecting surface 31 of the circular reflecting mirror 3 is used for reflecting the laser beam emitted by the laser, and the circular reflecting mirror 3 is fixed on the second surface 12 of the hemispherical mounting seat 1 through the connecting surface 32.

When the circular reflecting mirror 3 is fixed on the hemispherical mount 1, the connecting surface 32 of the circular reflecting mirror 3 may be adhered to the second surface 12 of the hemispherical mount 1 by an adhesive or an adhesive tape or other connecting members, or the connecting surface 32 of the circular reflecting mirror 3 may be fixed on the second surface 12 of the hemispherical mount 1 by a fixing member, or the fixed mounting of the circular reflecting mirror 3 on the hemispherical mount 1 may be realized by other realizable manners, which are not limited in this embodiment of the present application.

The circular reflecting mirror 3 in this embodiment is made of glass, and the reflecting surface can be obtained by plating a layer of reflecting film on one circular surface of circular glass having a certain thickness.

Illustratively, the material of the circular reflecting mirror in the embodiment of the application may be D263T ultra-thin colorless borosilicate glass.

The reflective film may be, for example, silicon oxide or silicon dioxide, or may be any other film material capable of reflecting the laser beam, which is not limited in this embodiment.

Wherein the thickness of the reflective film coated on the circular mirror 3 may be 5-50 μm.

In this embodiment of the present application, a film material that can reflect light in a specific wavelength band in laser light, but does not reflect or absorb light in other wavelength bands may be selected as the reflective surface 31 of the circular reflector 3 as required, so that interference of stray light may be reduced, and signal-to-noise ratio of the laser radar may be improved.

The number of hemispherical concave surfaces 21 on the mirror support 2 of the embodiment of the present application may be set according to the number of lasers in the laser radar.

Illustratively, referring to fig. 1, when the number of hemispherical concave surfaces 21 on the mirror support 2 is 3, it is illustrated that there are 3 lasers in the lidar, and one circular mirror 3 installed in one hemispherical concave surface 21 is used to reflect the laser beam emitted by a corresponding one of the 3 lasers.

In addition, the diameter of the circular mirror 3 in the embodiment of the present application may be the same as the outer diameter of the second surface 12 or slightly smaller than the diameter of the second surface 12 so that the side surface of the circular mirror 3 is flush with the side surface of the hemispherical mount 1.

In this application embodiment, at first, because the mount pad of circular speculum is hemispherical, consequently, the second surface of mount pad is circular, when the circular speculum is fixed on the hemispherical mount pad, the edge of circular speculum can not surpass the edge of second surface or surpass too much to can with the better laminating of the second surface of hemispherical mount pad, reduce the speculum because do not laminate between with the mount pad and lead to coming off or the probability of warp deformation appears from the mount pad.

Secondly, set up one or more hemisphere concave surface on reflector holder 2, and this hemisphere concave surface has the same camber with the hemisphere convex surface of hemisphere mount pad, based on this, when installing the hemisphere mount pad in the hemisphere concave surface, the hemisphere convex surface of mount pad can laminate with the hemisphere concave surface on the reflector holder 2, has improved the installation stability of mount pad on reflector holder 2.

Finally, the mounting seat is set to be of a hemispherical structure, and in the manufacturing and assembling process of the laser radar, when the position of the circular reflecting mirror needs to be adjusted, the position of the reflecting mirror can be adjusted by rotating the hemispherical mounting seat in the hemispherical concave surface, so that the convenience of adjusting the position of the reflecting mirror is improved.

In one embodiment, the hemispherical convex surface and the hemispherical concave surface are bonded by an adhesive.

In mounting the hemispherical mount 1 on the mirror support 2, the fixed mounting of the hemispherical mount 1 on the mirror support 2 can be achieved by applying an adhesive on the hemispherical convex surface and the hemispherical concave surface 21.

The adhesive may be a thermosetting adhesive, which is not cured at normal temperature and is cured after being heated at high temperature, for example, an epoxy resin adhesive.

Therefore, after the adhesive is coated in the hemispherical concave surface and/or the hemispherical convex surface, the reflector bracket 2 attached with the hemispherical mounting seat 1 is transferred to a high-temperature oven for high-temperature heating, so that the thermosetting adhesive is cured at high temperature, and the fixed mounting of the hemispherical mounting seat 1 on the reflector bracket 2 is realized.

In the embodiment of the application, heat is generated during the operation of the laser radar, so that the temperature of each component in the laser radar is increased, and the probability that the mounting seat falls off from the reflector bracket 2 due to melting of the adhesive caused by the temperature increase of the laser radar can be reduced by adopting the thermosetting adhesive.

In the present embodiment, when bonding the hemispherical convex surface and the hemispherical concave surface 21 by applying an adhesive to the hemispherical convex surface of the hemispherical mount 1 and/or the hemispherical concave surface 21 of the mirror holder 2, it is difficult to apply the adhesive uniformly.

Based on this, after the adhesive is cured, the gap between the hemispherical convex surface and the hemispherical concave surface 21 is larger where the adhesive is thicker, and the gap between the hemispherical convex surface and the hemispherical concave surface 21 is smaller where the adhesive is thinner, which affects the mounting accuracy of the hemispherical mount 1 on the mirror holder 2.

To solve the above problem, referring to fig. 4 and 5, in one embodiment, the hemispherical convex surface has one or more first grooves 13 protruding toward the second surface 12;

the hemispherical concave surface 21 has one or more through holes 22;

the first groove 13 is filled with an adhesive injected through the through hole 22;

the adhesive adheres the hemispherical mount 1 and the mirror support 2.

In the embodiment of the present application, one or more through holes 22 may be provided in the hemispherical concave surface 21 in the thickness direction of the mirror holder 2, wherein the through holes 22 have a first opening 221 located in the hemispherical concave surface 21 and a second opening 222 located opposite to the first opening 221.

Illustratively, the plurality of through holes 22 provided in the hemispherical concave surface 21 may be distributed centrally symmetrically, for example, to be distributed at the center point of the hemispherical concave surface 21. And at least one through hole 22 is formed at the vertex of the hemispherical concave surface 21 when it is covered on the supporting surface, thus facilitating the subsequent injection of the adhesive which is not yet cured to various positions of the hemispherical concave surface 21.

The first recess 13 is disposed at a position corresponding to the hemispherical convex surface and the through hole 22, so that when the hemispherical convex surface and the hemispherical concave surface 21 are bonded, the first opening 221 of the through hole 22 and the opening of the first recess 13 at least partially overlap.

Based on this, the adhesive may be injected into the first recess 13 located at the hemispherical convex surface through the second opening 222 of the through hole 22, and at this time, the adhesive may be stored in the first recess 13 of the hemispherical convex surface and adhered to the inner surface of the through hole 22 and the inner surface of the first recess 13 after curing, thereby achieving the fixation of the hemispherical mount 1 in the hemispherical concave surface 21.

In this embodiment of the application, since the first groove 13 is provided on the hemispherical convex surface of the hemispherical mount 1, the first groove 13 can store the adhesive, and the hemispherical convex surface and the hemispherical concave surface 21 are bonded by the adhesive stored in the first groove 13, compared with directly coating the adhesive on the bonding surfaces of the hemispherical convex surface and the hemispherical concave surface 21, the influence of the mounting accuracy of the hemispherical mount 1 on the mirror bracket 2 due to the uneven coating of the adhesive can be reduced.

The depth of the first groove 13 may be set as required, for example, 0.3mm.

In another embodiment, the through hole 22 is provided near the center of the hemispherical concave 21.

In the embodiment of the present application, when the number of through holes 22 provided on the hemispherical concave surface 21 is small, for example, when one through hole 22 is provided on the hemispherical concave surface 21, the through hole 22 may be provided at a position close to the center of the hemispherical concave surface 21.

Based on this, when the hemispherical convex surface is bonded with the hemispherical concave surface 21, the adhesive is injected into the bonding surface of the hemispherical concave surface 21 and the hemispherical convex surface through the second opening 222, and the adhesive can be stored in the central area of the bonding surface more, so that the uniformity of the adhesive force is improved, and the fixing stability of the mounting seat on the reflector bracket 2 is further improved.

When the adjusting structure for adjusting the position of the hemispherical concave is disposed at the center of the hemispherical concave, the through hole 22 may be disposed at a certain distance from the mounting hole 211 for mounting the adjusting structure, so as to reduce the influence on the mechanical strength of the mirror bracket due to the too close position of the mounting hole 211 and the through hole 22.

In another embodiment, it is also possible to provide only through holes in the hemispherical concave surface 21 and not to provide the first recess 13 in the hemispherical convex surface.

Since the hemispherical concave surface 21 and the hemispherical convex surface have the same radius of curvature, the hemispherical convex surface of the hemispherical mount 1 can be fitted with the hemispherical concave surface 21 on the mirror bracket 2 after the hemispherical mount 1 is placed in the hemispherical concave surface 21 of the mirror bracket 2. Based on this, the hemispherical convex surface can block the first opening 221 of the through hole 22, that is, the hemispherical convex surface exposed in the first opening 221 and the inner wall of the through hole 22 may form a groove-like shape.

At this time, an adhesive may be injected into the through hole 22 through the second opening 222, and the adhesive may be partially stored in the through hole 22 blocked by the hemispherical convex surface at the first opening 221, and partially infiltrate into the bonding surface between the hemispherical convex surface or hemispherical concave surface 21.

Based on this, after the adhesive is cured, the adhesive stored in the through hole 22 can achieve the fixation of the hemispherical convex surface and the hemispherical concave surface 21 by bonding the inner surface of the through hole 22 and the hemispherical convex surface exposed at the first opening 221.

In the case of bonding the hemispherical concave surface 21 and the hemispherical convex surface by this method, an adhesive having a certain viscosity may be selected so that as little adhesive as possible penetrates into the bonding surface between the hemispherical concave surface 21 and the hemispherical convex surface, and thus the influence on the mounting accuracy of the hemispherical mount 1 due to the uneven thickness of the adhesive on the bonding surface between the hemispherical convex surface and the hemispherical concave surface 21 can be reduced.

The number of through holes 22 on the hemispherical concave surface 21 may be determined according to the area of the hemispherical concave surface 21, and when the area of the hemispherical concave surface 21 is large, a larger number of through holes 22 may be disposed in the hemispherical concave surface 21, and when the area of the hemispherical concave surface 21 is small, a smaller number of through holes 22 may be disposed in the hemispherical concave surface 21.

Illustratively, referring to fig. 4, four through holes 22 may be provided on each hemispherical concave surface 21, and the four through holes 22 may be provided in different orientations in the hemispherical concave surface 21 (each through hole 22 is provided at the position shown in fig. 4) with the same spacing distance, so that when the hemispherical concave surface 21 and the hemispherical convex surface are bonded by the adhesive, the adhesive force can be more equalized, and the bonding firmness can be improved.

In addition, the size of the cross section of the through hole 22 described above may be determined according to the thickness at the hemispherical concave surface 21. When the thickness at the hemispherical concave surface 21 is thicker, a through hole 22 having a larger cross section may be provided, and when the thickness at the hemispherical concave surface 21 is thinner, a through hole 22 having a smaller cross section may be provided.

The cross-section of the through hole 22 may be circular, square, or any other shape, which is not limited in the embodiment of the present application.

In another embodiment, the through holes provided on the hemispherical concave surface 21 may also be provided as grooves, i.e. one or more second grooves are provided on the hemispherical concave surface 21 for receiving an adhesive bonding the hemispherical convex surface and the hemispherical concave surface 21.

When the hemispherical concave surface 21 and the hemispherical convex surface are bonded, the hemispherical convex surface bonded at the opening of the second recess can be in contact with the adhesive in the second recess, and therefore, after the adhesive stored in the second recess is cured, the fixed mounting of the hemispherical mount 1 in the hemispherical concave surface 21 can be achieved.

In the embodiment of the application, the bonding of the hemispherical concave surface 21 and the hemispherical concave surface 21 is achieved by storing the adhesive bonding the hemispherical concave surface 21 and the hemispherical convex surface in the second groove, and compared with directly coating the adhesive on the bonding surface of the hemispherical concave surface 21 and the hemispherical convex surface, the influence on the mounting accuracy of the hemispherical mount 1 on the mirror bracket 2 due to uneven coating of the adhesive can be reduced.

Illustratively, the number of second grooves may be greater than the number of through holes 22, and the second grooves are distributed at different locations of the hemispherical convex surface. Illustratively, any adjacent second grooves are equiangularly or equispaced on the hemispherical convex surface.

In another embodiment it is also possible to provide the first recess 13 only on the hemispherical convex surface and not to provide a through hole in the hemispherical concave surface.

It should be noted that, the implementation manner of bonding the hemispherical convex surface and the hemispherical concave surface 21 by the first groove 13 on the hemispherical convex surface may refer to the implementation manner of bonding the hemispherical concave surface 21 and the hemispherical convex surface by the second groove disposed in the hemispherical concave surface 21, which is not described herein.

Referring to fig. 6, in one embodiment, the mirror support 2 includes:

a body portion 23 having a plurality of mounting areas, one of the mounting areas having one of the hemispherical concave surfaces 21 therein, and a land area located around the hemispherical concave surface 21; the included angle of the plane where the platform areas of the adjacent installation areas are located is an obtuse angle;

and connection portions 24 connected to both ends of the body portion 23.

As is clear from the above description, the number of hemispherical concave surfaces 21 on the mirror support 2 may be one or more. When the mirror support 2 has a plurality of hemispherical concave surfaces 21, the body portion 23 has a plurality of mounting areas, each having one hemispherical concave surface 21 therein.

Since each circular mirror 3 mounted on the mirror support 2 serves to reflect an incident laser beam in a different direction, the plane in which the land areas of adjacent mounting areas are located can be set to an obtuse angle when the mirror support 2 is designed, so that the opening of each hemispherical concave surface 21 can have a different orientation.

Based on this, the second surfaces 12 of the plurality of hemispherical mounts 1 mounted on the mirror support 2 also have different orientations, and thus the circular mirrors 3 fixed on the different hemispherical mounts 1 also have different orientations, thereby achieving reflection of the incident laser beam to different directions.

Wherein connecting portions 24 are connected to both ends of the main body portion 23 in the long axis direction, the connecting portions 24 serve to fix the mirror holder 2 to the housing 4 of the laser emitting assembly.

Illustratively, referring to fig. 4 and 6, in one embodiment, the connection portion 24 of the mirror support 2 is further provided with a first bolt hole 25, based on which first bolt hole 25 a bolt can be used to fix the mirror support 2 to the housing 4 of the laser emitting module.

The first bolt hole 25 may be disposed at an intermediate position of the connecting portion 24, so that the balance of stress of the mirror support 2 may be improved, and thus the fixing stability of the mirror support 2 on the housing 4 may be improved.

In addition, as is clear from the above description, the lidar generates heat during operation, which causes the temperature of the mirror support 2 and the housing 4 to rise, so that the housing 4 and the mirror support 2 undergo thermal expansion and contraction many times, and further causes loosening of bolts for fixing the mirror support 2.

Based on this, in the embodiment of the present application, the aperture of the first bolt hole 25 located on the connecting portion 24 should not be smaller than 1.6mm, and the reflector bracket 2 is fixed by the bolt with a larger diameter, so that the probability that the reflector bracket 2 falls off from the housing 4 in the process of multiple expansion with heat and contraction with cold can be reduced.

It should be noted that if the area of the connecting portion 24 of the mirror support 2 is large, the stability of fixing the mirror support 2 to the housing 4 can also be improved by providing a plurality of first bolt holes 25 on each connecting portion 24, that is, by fixing the mirror support 2 to the housing 4 with a plurality of bolts.

In one embodiment, the connection portion 24 includes: a first connection portion 242 and a second connection portion 243;

the first connection portions 242 are connected to both ends of the body portion 23 and extend toward the opening side of the hemispherical concave surface in the thickness direction of the body portion 23;

the second connection portion 243 is connected to a side of the first connection portion 242 remote from the main body portion 23.

In this embodiment, the mirror support 2 further includes a first connection portion 242, where the first connection portion 242 is connected to two ends of the main body portion 23 along the long axis direction of the main body portion 23, and extends along the first direction, which is the thickness direction of the mirror support 2, toward the open end of the hemispherical concave 21.

Based on this, when the hemispherical mount 1 is mounted in the hemispherical concave surface 21, the circular reflecting mirror 3 fixed on the second surface 12 of the hemispherical mount 1 is located in the space surrounded by the body part 23 and the first connection part 242, so that the circular reflecting mirror 3 can be protected by the first connection part 242.

In addition, when the mirror support 2 is mounted on the housing 4 of the laser emitting assembly, the first connection portion 242 can also support the mirror support 2 in the first direction, so that a certain gap is provided between the circular mirror 3 located on the mirror support 2 and the housing 4, that is, a certain adjustment space is reserved for the circular mirror 3, so that the mounting position of the circular mirror 3 on the mirror support 2 can be adjusted when needed.

In one embodiment, the main body 23 has a first long side 231 disposed opposite to each other along the long axis direction, and a second long side 232;

the first connection portion 242 gradually increases in width along the direction from the first long side 231 to the second long side 232.

Referring to fig. 6, it can be seen from fig. 6 that the body portion 23 of the mirror holder 2 has an elongated structure having a first long side 231 and a second long side 232 on the body portion 23, wherein the first connection portion 242 is connected to both sides of the body portion 23 and gradually increases in width in a direction from the first long side 231 to the second long side 232.

Wherein the first long side 231 is formed by the outer edge connection surrounding a plurality of land areas above the hemispherical concave 21, and the second long side 232 is formed by the outer edge connection surrounding a plurality of land areas below the hemispherical concave 21.

Illustratively, the hemispherical concave surface 21 may be upward in the direction indicated by arrow z.

Illustratively, the first connecting portion 242 may be approximately triangular or trapezoidal in configuration when viewed from the side.

When the width increase of the first connecting portion 242 in the direction of the first long side 231 to the second long side 232 is different, the inclination of the main body portion 23 when mounted on the housing 4 is different, and therefore, the width increase of the first connecting portion 242 in the direction of the first long side 231 to the second long side 232 can be adjusted as needed when manufacturing the mirror holder 2.

In one embodiment, the mirror support 2 also has a stiffening plate;

the reinforcing plate is fixed in a space defined by the first connecting portion 242 and the second connecting portion 243 and is connected to the second long side 232.

As is apparent from the above description, the mirror support 2 may be provided with a plurality of hemispherical concave surfaces 21, and when the number of hemispherical concave surfaces 21 provided on the mirror support 2 is large, the length of the main body portion 23 of the mirror support 2 may be long.

In addition, as is apparent from the above description, in order to make each circular mirror 3 fixed to the mirror support 2 have a different orientation, the angle of the plane in which the land areas of the adjacent mounting areas are located is set to be an obtuse angle. Based on this, a certain curvature will be present for the whole body portion 23.

In the use process of the laser radar, the long-strip-shaped reflecting mirror support 2 with a certain radian is easy to deform due to factors such as stress or expansion and contraction.

Based on this, in the embodiment of the present application, it is also possible to improve the mechanical strength of the mirror holder 2 and reduce the deformation amount of the mirror holder 2 by providing a reinforcing plate in the space surrounded by the first connection portion 242 and the second connection portion 243.

Wherein the reinforcement plate may be connected to the second long side 232 of the body portion 23.

As is apparent from the above description, when the mirror holder 2 is fixed to the housing 4 of the laser radar through the first bolt hole 25, the first bolt hole 25 may be provided at a middle position of the connecting portion 24, and since the first connecting portion 242 gradually widens in a direction from the first long side 231 to the second long side 232, a distance between the second long side 232 and the first bolt hole 25 is greater than a distance between the first long side 231 and the first bolt hole 25. Based on this, the second long side 232 receives a smaller tightening force of the bolt than the first long side 231, resulting in a more easily deformed main body portion 23 where the second long side 232 is located.

In the embodiment of the present application, by attaching the reinforcing plate to the second long side 232, the deformation amount of the main body portion 23 near the second long side 232 in the long axis direction can be reduced, and thus the deformation amount of the entire mirror holder 2 can be reduced.

Referring to fig. 7, an embodiment of the present application further provides a laser emitting module, including:

a housing 4;

and a mirror assembly provided by any of the embodiments above;

wherein the mirror assembly is mounted on the housing 4.

Referring to fig. 7, the mirror support 2 in any of the above embodiments may be mounted on the housing 4 in the position shown in fig. 7.

As can also be seen in fig. 7, the housing 4 has laser channels 41 thereon, and each circular mirror 3 on the mirror assembly is capable of covering at least part of the exit of one of the laser channels 41 when the mirror assembly is mounted on the housing 4. Based on this, the laser beam emitted from the laser can be incident on the circular mirror 3 from the outlet of the laser channel 41, so that the circular mirror 3 can reflect the incident laser beam.

The material of the housing 4 in the embodiment of the present application may be an alloy material, for example, ADC12 aluminum alloy.

The ADC12 aluminum alloy has better casting performance and pressure resistance, so the shell 4 made of the aluminum alloy material can be integrally formed during manufacturing, and has better mechanical strength.

In one embodiment, the mirror assembly comprises a mirror support 2;

a first limiting structure is arranged on the second connecting part 243 of the reflector bracket 2;

The shell 4 is provided with a second limiting structure matched with the first limiting structure;

the first limit structure and the second limit structure are matched to limit the installation position of the reflector bracket 2 on the shell 4.

As the service life of the lidar increases, there is a possibility that the bolts for fixing the mirror holder 2 to the housing 4 come loose. Based on this, when the laser radar is mounted on a mobile device, for example, an automobile, during the movement of the mobile device, a relative movement may occur between the mirror support 2 and the housing 4, which results in a change in the relative position between the circular mirror 3 and the laser channel 41, and further, the emission angle of the laser beam emitted by the laser emission module changes, which affects the ranging accuracy of the laser radar.

Based on this, still be provided with first limit structure on the speculum support 2 of this application embodiment, set up on the casing 4 with first limit structure complex second limit structure, through first limit structure and second limit structure's cooperation, can slow down when the bolt appears not hard up, the speculum support 2 is relative movement for casing 4 production, and then has reduced the probability that the emergence angle of the laser beam of laser emission module emergence changes.

In addition, when the mirror support 2 is mounted on the housing 4, the assembly accuracy between the mirror support 2 and the housing 4 can be improved through the first limiting structure and the second limiting structure, and the mounting tolerance is reduced.

The number of the first limiting structures on the mirror support 2 may be determined according to the shape and size of the mirror support 2, the number of the second limiting structures that can be provided on the housing 4 and cooperate with the first limiting structures, and the like.

Illustratively, a first limiting structure may be provided on at least one connecting portion 24 of the mirror support 2, such that movement of the mirror support 2 in the long axis direction may be limited.

In one embodiment, the first limiting structure includes: at least one stopper pin 241; the second limiting structure is a limiting groove 42 matched with the limiting pin 241;

or alternatively, the process may be performed,

the first limiting structure is at least one limiting groove; the second limiting structure is a limiting pin matched with the limiting groove.

Referring to fig. 8, the first limiting structure may be a limiting pin 241 disposed at a portion end of at least one connection portion 24, and the second limiting structure may be a limiting groove 42 disposed on the housing 4 and corresponding to the limiting pin 241.

In mounting the mirror holder 2 on the housing 4, the definition of the mounting position of the mirror holder 2 on the housing 4 can be achieved by inserting the stopper pin 241 located on the connecting portion 24 into the stopper groove 42.

Similarly, when the first limiting structure is a limiting groove and the second limiting structure is a limiting pin, the limiting of the mounting position of the reflector bracket 2 on the housing 4 can be realized by clamping the limiting groove around the limiting pin.

Referring to fig. 8, in one embodiment, the housing 4 has a third surface 44, and the third surface 44 is provided with a second bolt hole 43 that mates with the first bolt hole 25, and the mirror support 2 can be fixedly mounted on the housing 4 by inserting a bolt through the first bolt hole 25 and fixing the bolt in the second bolt hole 43.

In this application embodiment, realize the fixed mounting of speculum support on the casing through the bolt, can be when need changing speculum support, mount pad and/or circular speculum, conveniently dismantle the speculum support from the casing, promoted the convenience that speculum support, mount pad and/or circular speculum changed.

In one embodiment, the reflector holder 2 is made of the same material as the hemispherical mount 1, and the hemispherical mount 1 has a first thermal expansion coefficient, and the circular reflector has a second thermal expansion coefficient, wherein a difference between the first thermal expansion coefficient and the second thermal expansion coefficient is smaller than a first threshold value.

The material of the shell of this application embodiment is aluminum alloy, and its coefficient of thermal expansion is 23.6ppm, and the material of circular speculum is glass, and its coefficient of thermal expansion is 7.2ppm, and it can be seen that the coefficient of thermal expansion of shell is more than 3 times of the coefficient of thermal expansion of circular speculum.

If the reflector bracket 2 and the hemispherical mounting seat 1 are made of the same aluminum alloy material as the shell, the deformation of the hemispherical mounting seat 1 is far greater than that of the round reflector when the temperature of the hemispherical mounting seat 1 and the round reflector is increased due to the fact that the thermal expansion coefficient between the round reflector and the hemispherical mounting seat 1 is greatly different from that of the round reflector due to the fact that the laser radar works and heats. Based on this, the hemispherical mounting base 1 with larger deformation easily tears the round reflector with smaller deformation, or causes the buckling deformation of the round reflector to even drop from the mounting base, thereby affecting the service life of the laser emission module.

Based on this, in the embodiment of the present application, the mounting base and the mirror support may be made of materials having a thermal expansion coefficient similar to that of the mirror, that is, the difference between the thermal expansion coefficients of the mounting base having the first thermal expansion coefficient and the mirror having the second thermal expansion coefficient is smaller than the first threshold, so that the deformation amount between the mounting base and the mirror is similar, and the probability that the mirror tears, warp deformation or falls off from the mounting base may be reduced.

Illustratively, the reflector holder and the hemispherical mount 1 are made of kovar.

For example, it may be kovar alloy 4J29, which has a thermal expansion coefficient of 5.9ppm, which is close to that of 7.2ppm of the glass reflector, so that when the temperatures of the reflector and the mount are raised, the deformation amounts of the reflector and the mount are relatively close, and the probability of tearing, buckling deformation or falling off the reflector from the mount can be reduced.

In addition, the tensile strength of the kovar alloy is 2 times that of the aluminum alloy, so that the mechanical strength of the reflector bracket 2 and the hemispherical mounting seat can be improved by adopting the kovar alloy to manufacture the reflector bracket 2 and the hemispherical mounting seat, the probability of deformation of the reflector bracket 2 is reduced, and the service life of the reflector bracket 2 is prolonged.

In the embodiment of the present application, simulation tests are performed on the assembly process and the working process of the mirror assembly provided in the embodiment of the present application and the mirror assembly in the related art through the finite element simulation system at 115 ℃ and the deformation under the condition of applying an external force, and the results are as follows:

referring to fig. 9, test 1: when the reflector bracket and the mounting seat are made of aluminum alloy materials and the reflector bracket is not provided with a reinforcing plate, the maximum deformation of the reflector bracket is 162 mu m and the maximum deformation of the reflector is 154 mu m at 115 ℃.

Referring to fig. 10, test 2: in the case of manufacturing the reflector bracket by adopting the kovar alloy, manufacturing the mounting seat by adopting the aluminum alloy, and under the condition that the reflector bracket does not have a reinforcing plate, the maximum deformation of the reflector bracket is 83 mu m and the deformation of the reflector is 76 mu m at 115 ℃.

Referring to fig. 11, test 3: in the case of manufacturing the reflector bracket by adopting the kovar alloy, manufacturing the mounting seat by adopting the aluminum alloy, and providing the reflector bracket with the reinforcing plate, the maximum deformation of the reflector bracket is 56 mu m and the maximum deformation of the reflector is 53 mu m at 115 ℃.

Referring to fig. 12, test 4, in the case where the mirror holder and the mount were made of the above-mentioned kovar alloy and the mirror holder had the reinforcing plate, the maximum deformation amount of the mirror holder was 44 μm and the maximum deformation amount of the mirror was 41 μm at 115 ℃.

The normalized deformation results of the above experiments 1 to 4 are shown in table 1 below:

TABLE 1 deformation amount test results of mirror supports and mirrors of different materials

From the test, the deformation of the reflecting mirror assembly at high temperature is small, and the service life of the reflecting mirror assembly is prolonged.

In addition, in the embodiment of the present application, the maximum stress and the warpage of the bonding surface between the mirror and the mounting seat in the mirror assembly provided in the embodiment of the present application and the mirror assembly in the related art can be simulated by the finite element simulation system, and the results are shown in the following table 2:

referring to fig. 13, test 5: the reflector bracket and the mounting seat are made of aluminum alloy materials, and the reflector is square.

Referring to fig. 14, test 6: the reflector bracket is made of kovar alloy, and is not provided with a reinforcing plate, and the reflector is square.

Referring to fig. 15, test 7: the reflector bracket is made of kovar alloy, and is provided with a reinforcing plate, and the reflector is square.

Referring to fig. 16, test 8, a reflector holder and a mount were made of kovar, and the reflector holder had a reinforcing plate and the reflector was circular.

TABLE 2 maximum stress of mirror bonding surfaces under different test conditions

Maximum stress (MPa) of mirror bonding surface	Test 5	Test 6	Test 7	Experiment 8
					-40℃	43.6	26.8	21.5	14.6
115℃	49.9	13.8	14.0	10.2

As can be seen from table 2, in the mirror assembly provided by the embodiments of the present application, in test 8, the bonding stress between the mirror and the mount was minimal, that is, the use of the circular mirror and hemispherical mount provided by the embodiments of the present application in the lidar can reduce the occurrence of structural failure of the mirror and the lowest probability of falling off from the mount.

TABLE 3 deformation of different shape mirrors mounted on mounting base

F0, F1 and F2 in table 3 identify three mirrors located at different positions of the mirror support, respectively. As can be seen from Table 3, the use of the laser transmitting module in the laser radar can greatly reduce the warpage of the reflector in the use process of the laser radar.

The embodiment of the application also provides a laser radar, which comprises:

a laser receiving module;

a processor;

and any one of the above laser emission modules.

Illustratively, the laser emitting module has one or more lasers for emitting laser beams in addition to the housing and mirror assembly provided by the above embodiments. The lasers may include, among others, pulsed laser diodes (pulsed laser diode, PLD), semiconductor lasers, fiber lasers, etc.

In addition, the laser emission module can also comprise a MEMS component for changing the emitting direction of the laser and a lens component for expanding the laser beam.

Based on this, the laser beam emitted by the laser may be incident on the circular mirror after passing through the laser channel 41, reflected by the circular mirror, incident on the mirror unit in the MEMS element, reflected by the mirror unit in the MEMS element, incident on the lens element, and emitted after being expanded.

And the laser receiving assembly is used for receiving the echo light beam reflected by the measured target.

The laser receiving assembly typically employs photodiodes (e.g., avalanche photodiodes (avalanche photo diode, APD), silicon photomultipliers (silicon photomultiplier, siPM), etc.) as detectors to receive the echo beam and to perform photoelectric conversion by digital-to-analog converters (digital analog converter, ACD). In practical applications, a detector array is generally used in the lidar to increase the receiving efficiency and improve the performance of the echo beam.

The processor is used for controlling the laser emission module and the laser receiving module so that the laser emission module and the laser receiving module can work normally.

Illustratively, the processor may provide driving voltages for the laser emitting module and the laser receiving module, respectively, and the processor may also provide control signals for the laser emitting module and the laser receiving module.

By way of example, the processor may be a general-purpose processor, such as a central processing unit (central processing unit, CPU), a network processor (network processor, NP), or the like; the processor may also be a digital signal processor (digital signal processing, DSP), an application specific integrated circuit (application specific integrated circuit, ASIC), a field-programmable gate array (field-programmable gate array, FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware components, or the like.

It will be appreciated that the laser beam may also be referred to as a laser pulse, laser, emission beam, or the like.

The above embodiments are only for illustrating the technical solution of the present utility model, and are not limiting; while the utility model has been described in detail with reference to the foregoing embodiments, it will be appreciated by those skilled in the art that variations may be made in the techniques described in the foregoing embodiments, or equivalents may be substituted for elements thereof; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present utility model, and are intended to be included in the scope of the present utility model.

Claims

1. A mirror assembly, the mirror assembly comprising:

2. The mirror assembly according to claim 1, wherein,

the hemispherical convex surface and the hemispherical concave surface are bonded by an adhesive.

3. The mirror assembly according to claim 2, wherein,

the hemispherical convex surface is provided with one or more first grooves protruding towards the second surface;

the hemispherical concave surface is provided with one or more through holes;

the first groove is filled with adhesive injected through the through hole;

the adhesive adheres the hemispherical mount and the mirror support.

4. A mirror assembly according to claim 3, wherein said through hole is provided near the center of said hemispherical concave surface.

5. The mirror assembly according to claim 4, wherein the mirror support comprises:

and a connection part connected to both ends of the body part.

6. The mirror assembly according to claim 5, wherein said connecting portion comprises: a first connection portion and a second connection portion;

7. The mirror assembly according to claim 6, wherein,

the main body part is provided with a first long side and a second long side which are oppositely arranged along the long axis direction;

8. The mirror assembly according to claim 7, wherein the mirror support further has a stiffener;

the reinforcing plate is fixed in a space surrounded by the main body part and the first connecting part and is connected with the second long edge.

9. The mirror assembly according to any one of claims 1-8, wherein said mirror support is of the same material as said hemispherical mount, and said hemispherical mount has a first coefficient of thermal expansion, said mirror has a second coefficient of thermal expansion,

Wherein the difference between the first coefficient of thermal expansion and the second coefficient of thermal expansion is less than a first threshold.

10. The mirror assembly of claim 9, wherein the mirror support is a kovar.

11. A laser emitting module, comprising:

a housing;

and a mirror assembly as claimed in any one of claims 2 to 10;

wherein the mirror assembly is mounted on the housing.

12. The laser emitting module of claim 11, wherein the mirror assembly comprises: a mirror support;

13. The laser emitting module as claimed in claim 12, wherein,

the first limiting structure is at least one limiting pin, and the second limiting structure is a limiting groove matched with the limiting pin;

or alternatively;

14. A lidar, the lidar comprising:

a laser receiving module;

a processor;

and the laser emitting module of any one of claims 11-13.