WO2020147625A1

WO2020147625A1 - Scanning device and laser radar

Info

Publication number: WO2020147625A1
Application number: PCT/CN2020/070853
Authority: WO
Inventors: 高永丰; 向少卿
Original assignee: 上海禾赛光电科技有限公司
Priority date: 2019-01-14
Filing date: 2020-01-08
Publication date: 2020-07-23
Also published as: CN109765541B; CN109765541A

Abstract

A scanning device and a laser radar. The scanning device comprises at least two galvanometers (110) sequentially arranged along an optical path, each galvanometer (100) being provided with a moving part (111), the moving part (111) having a reflecting surface (111r) suitable for reflection of light rays, and the galvanometer (110) changing the propagation direction of the light rays reflected by the reflecting surface (111r) by means of the swinging of the moving part (111); and at least one elastic connecting member (120) having two ends (121) respectively connected to the moving parts (111) of the two adjacent galvanometers (110). According to the scanning device, on the premise that the machining and assembling precision requirements are not increased or even reduced, the swinging of the moving parts (111) of the at least two galvanometers (110) is fused into the same resonant mode according to a certain phase, so that the cost is reduced and the performance is improved.

Description

Scanning device and lidar

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office, the application number is 201910034596.X, and the invention title is "Scanning Device and Lidar" on January 14, 2019, the entire content of which is incorporated into this application by reference .

Technical field

The invention relates to the field of laser detection, in particular to a scanning device and a laser radar.

Background technique

Lidar is a commonly used ranging sensor, which has the characteristics of long detection range, high resolution, and low environmental interference. It is widely used in intelligent robots, unmanned aerial vehicles, unmanned driving and other fields. In recent years, autonomous driving technology has developed rapidly, and lidar has become indispensable as its core sensor for distance sensing.

In the galvanometer-type solid-state lidar, light is reflected by the reflective surface of the galvanometer to form light for scanning. The scanning field of view that can be achieved by a single galvanometer is often insufficient to meet the field angle requirements of the device. For application requirements, multiple galvanometers are often set in the same lidar. In order to increase the angle of view as much as possible, the galvanometer needs to work at its resonant frequency; in practical applications, due to the existence of process errors, the resonant frequencies of independent galvanometers are not consistent.

The increase in the accuracy of the resonance frequency is often accompanied by an increase in the accuracy requirements of the galvanometer processing and assembly, resulting in an increase in equipment costs.

Summary of the invention

The problem solved by the present invention is to provide a scanning device and a lidar, which does not increase the requirements for the processing and assembly difficulty of the galvanometer, but also enables the moving parts of the at least two galvanometers to swing in the same resonance mode to achieve low Both cost and high performance.

To solve the above problems, the present invention provides a scanning device, including:

At least two galvanometers arranged in sequence along the optical path, the galvanometer has a moving part, the moving part has a reflective surface suitable for reflecting light, and the galvanometer changes the reflection surface through the swing of the moving part. The propagation direction of the reflected light; at least one elastic connecting member, the elastic connecting member has two ends, and the two ends are respectively connected to the moving parts of two adjacent galvanometers.

Optionally, the reflective surfaces of the at least two galvanometer mirrors are arranged opposite each other in sequence, so that the light rays are sequentially reflected on the reflective surfaces to change the propagation direction of the light rays.

Optionally, the at least two galvanometers have the same designed resonance frequency.

Optionally, the elastic connecting member includes a spring.

Optionally, the elastic connecting member and the moving part are made integrally; or, the elastic connecting member is fixedly connected to the moving part.

Optionally, each of the at least two galvanometers has a rotating shaft, the moving part swings around the rotating shaft, and the rotating shafts of the at least two galvanometers are arranged parallel to each other; the elastic connecting member is arranged on the rotating shaft In a first plane that is perpendicular to each other, and the elastic connecting member undergoes elastic deformation in the first plane.

Optionally, the moving part has an axisymmetric structure with respect to the first plane.

Optionally, the moving part has at least one end surface perpendicular to the reflecting surface of the moving part; the two ends of the elastic connecting member are respectively connected to the moving parts of two adjacent galvanometers The end faces are connected.

Optionally, the rotation axes of the two adjacent galvanometers define a second plane; the two ends of the elastic connecting member connecting the two adjacent galvanometers are located on the second plane One side.

Optionally, the rotation axes of the two adjacent galvanometers define a second plane; the two ends of the elastic connecting member connecting the two adjacent galvanometers are respectively located on the second plane On both sides.

Optionally, the elastic connecting member has any shape of a V shape, a U shape, an arc shape, a Z shape or an S shape.

Optionally, the galvanometer includes a MEMS galvanometer.

Optionally, the galvanometer is a one-dimensional galvanometer or a two-dimensional galvanometer.

In addition, the present invention also provides a laser radar, including: a laser emitting device, a scanning device, and a receiving device. The scanning device is the scanning device of the present invention.

Compared with the prior art, the technical solution of the present invention has the following advantages:

In the technical solution of the present invention, the moving parts of the two adjacent galvanometers are connected by the elastic connecting member, so the moving parts of the two adjacent galvanometers can be realized in the same resonance mode Even if there is a difference in resonant frequency, the swing of the moving parts of the two adjacent galvanometers can be merged into the same resonant mode according to a certain phase, that is, the technical solution of the present invention can not increase or even reduce the processing Under the premise of the requirements of assembly accuracy, the swings of the moving parts of the at least two galvanometers are merged into the same resonant mode according to a certain phase, so that both cost reduction and performance improvement are taken into consideration.

In an optional solution of the present invention, the at least two galvanometers have the same designed resonance frequency. A galvanometer with the same designed resonance frequency is provided in the scanning device, and the resonance modes of the at least two galvanometers are similar, which can effectively improve the stability of the resonance mode to which the at least two galvanometers are fused, which is beneficial to Improve the stability and accuracy of the scanning device.

In an alternative solution of the present invention, the reflecting surfaces of the at least two galvanometer mirrors are arranged opposite each other in sequence, and the light rays are sequentially reflected on the reflecting surfaces to change the propagation direction; therefore, as the moving part swings, The changing angle of the propagation direction of the light rays reflected multiple times by the reflecting surfaces of the at least two galvanometer mirrors also increases, thereby effectively expanding the field of view of the scanning light rays formed by the scanning device.

In an alternative solution of the present invention, the elastic connecting member can be manufactured integrally with the moving part, so that the elastic connecting member can be manufactured during the manufacturing process of the galvanometer, so as to improve the process accuracy and reduce the process cost; The elastic connecting member may also be fixedly connected to the moving part, that is, the arrangement of the elastic connecting member does not need to affect the existing process of the galvanometer. The flexible arrangement of the elastic connecting member can effectively reduce the manufacturing cost of the scanning device.

In an alternative solution of the present invention, the elastic connecting member is arranged in a first plane perpendicular to the rotation axis of the at least two galvanometers, so that the direction of elastic deformation of the elastic connecting member is located in the first plane. In the plane, the direction in which the elastic connecting member is elastically deformed is matched with the swing direction of the at least two galvanometers, so as to effectively realize the fusion of the same resonance mode.

In an alternative solution of the present invention, the moving part is an axisymmetric structure with respect to the first plane, which can effectively ensure the stability of the moving parts of the at least two galvanometers that swing in the same resonance mode, and can effectively ensure The reliability and stability of the scanning device.

BRIEF DESCRIPTION

1 is a schematic diagram of the optical path structure of the first embodiment of the technical solution of the present invention;

2 is a schematic diagram of the optical path of scanning light formed by the galvanometer;

3 is a schematic diagram of the optical path structure of the second embodiment of the technical solution of the present invention;

4 is a schematic diagram of the optical path structure of the third embodiment of the technical solution of the present invention.

detailed description

It can be known from the background technology that the scanning device with multiple galvanometers in the prior art often has the problem of high requirements for the processing and assembly accuracy of the galvanometer. For example, when designing a galvanometer with a resonant frequency of 600Hz, due to process fluctuations and processing errors, after the processing is completed, the resonance frequency of a single galvanometer may be 601Hz, or 602Hz, or 599Hz, 598Hz.

On the other hand, the existing laser radar scanning device also has the problem of too small field of view. The scanning field angle that a single galvanometer can achieve is often insufficient to meet the field angle requirements of the device. To solve this problem, one method is to use multiple laser beams to be incident on the mirror from different angles, so as to splice a larger field of view to meet the demand. However, due to the use of multiple lasers, multiple relatively independent optical transceiver modules are required, and the assembly accuracy between each other needs to meet certain requirements, which will increase the cost of the system. In addition, multi-field splicing also greatly increases the complexity of related control methods.

Another method is to use a polygonal galvanometer to vibrate at the same frequency and synchronized phase to reflect the received light multiple times, thereby increasing the scanning angle of view. In order to maximize the field of view angle, the galvanometer used in this method needs to work at the same resonance frequency. However, the difference in resonance frequency between independent galvanometers will cause the scanning angle to appear beat frequency, which will cause the scanning field of view to be unstable, and there will be problems such as no scanning in some areas and fast scanning speed in some areas.

In addition, due to the high quality factor (Q value) of the galvanometer and the small bandwidth, using the same frequency to drive the independent galvanometer will also easily cause the problem of extremely small field of view.

To solve the technical problem, the present invention provides a scanning device, including:

At least two galvanometers arranged in sequence along the optical path, the galvanometer has a moving part, the moving part has a reflective surface suitable for reflecting light, and the galvanometer changes the reflection surface through the swing of the moving part. The propagation direction of the reflected light; at least one elastic connecting member, the elastic connecting member has two ends, and the two ends are respectively connected to the moving parts of two adjacent galvanometers. The technical solution of the present invention can make the swings of the moving parts of the at least two galvanometers merge into the same resonance mode according to a certain phase without increasing or even reducing the requirements for processing and assembly accuracy, thereby taking into account cost reduction and performance improve.

In order to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, specific embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings.

Referring to Fig. 1, a schematic diagram of the optical path structure of the first embodiment of the technical solution of the present invention is shown.

As shown in Fig. 1, the scanning device includes: at least two galvanometers 110 arranged in sequence along the optical path, the galvanometer 110 has a moving part 111, and the moving part 111 has a reflecting surface 111r suitable for reflecting light. The galvanometer 110 changes the propagation direction of the light reflected by the reflective surface 111r through the swing of the moving part 111; at least one elastic connecting member 120, the elastic connecting member 120 has two ends 121, the two Each end 121 is respectively connected with the moving parts 111 of the two adjacent galvanometers 110.

The moving parts 111 of the two adjacent galvanometers 110 are connected by the elastic connecting member 120, so the moving parts 111 of the two adjacent galvanometers 110 can swing in the same resonance mode Even if there is a difference in resonance frequency, the swing of the moving part 111 of the two adjacent galvanometers 110 can be merged into the same resonance mode according to a certain phase, that is, the technical solution of the present invention can not increase or even decrease Under the premise of processing and assembly accuracy requirements, the swings of the moving parts 111 of the at least two galvanometers 110 are merged into the same resonance mode according to a certain phase, so as to achieve both cost reduction and performance improvement.

The technical solution of the present invention will be described in detail below in conjunction with the drawings.

The galvanometer 110 includes a moving part 111 with a reflecting surface 111r for reflecting the received light, and the movement of the moving part 111 changes the propagation direction of the light reflected by the reflecting surface 111r to form The light used for scanning.

With reference to FIG. 2, a schematic diagram of the optical path of the scanning light formed by the galvanometer is shown.

A part of the surface of the moving part 111 of the galvanometer 110 is the reflecting surface 111r, and the light projected to the reflecting surface 111r is reflected by the reflecting surface 111r to form a light 132a.

The galvanometer 110 has a rotating shaft 112, and the moving part 111 swings around the rotating shaft 112; as the moving part 111 swings, the reflecting surface 111r also swings accordingly.

It should be noted that FIG. 1 only schematically shows the rotating shaft 112. In an embodiment of the present invention, the axis of the rotating shaft 112 is arranged perpendicular to the paper surface; the moving part 111 swings around the rotating shaft 112. However, this setting method is only an example, and the present invention does not limit the position and setting method of the rotating shaft.

As shown in Figure 2, when the moving part 111 rotates around the rotating shaft 112 by an angle α, the reflecting surface 111r also rotates at an angle of α; at this time, the light formed by the reflection of the reflecting surface 111r The angle between 132b and the ray 132a formed when it is not rotating is 2α. Therefore, when the swing angle of the galvanometer 110 is α, the field of view of the light rays formed by the reflecting surface 111r is 2α.

1, the scanning device includes at least two galvanometers 110, the at least two galvanometers 110 are arranged in sequence along the optical path, and the reflective surfaces 111r of the at least two galvanometers 110 are arranged opposite each other in sequence, so that The light rays are sequentially reflected on the reflecting surface 111r to change the propagation direction of the light rays.

Therefore, as the moving part 111 swings, the changing angle of the propagation direction of the light reflected multiple times by the reflecting surface 111r of the at least two galvanometer mirrors 110 also increases, thereby effectively expanding the scanning device formed The angle of view of the scanning light.

Specifically, as shown in FIG. 1, the scanning device includes two galvanometer mirrors 110 arranged along the optical path. The light 131 is projected onto a reflective surface 111r of the galvanometer 110 and reflected by the reflective surface 111r to form a light 132a. When the moving part 111 of the galvanometer 110 is rotated by an angle α, a light 132b is formed, and the angle between the light 132a and the light 132b is 2α, that is, the field angle of the light formed by a galvanometer reflection is 2α .

The light 132a is projected onto the reflecting surface 111r of the other galvanometer 110, and is reflected by the reflecting surface 111r of the other galvanometer 110 to form a light 133a; at the same time, the moving part 111 of the other galvanometer 110 Correspondingly, when α is also rotated, a ray 133b is formed, and the angle between the ray 133a and the ray 133b is 4α, that is, the field angle of the light formed by the reflection of the two galvanometer mirrors is 4α.

In this embodiment, the at least two galvanometers 110 have the same designed resonance frequency. A galvanometer 110 with the same designed resonance frequency is provided in the scanning device. The resonance modes of the at least two galvanometers 110 are similar, which can effectively improve the stability of the same resonance mode to which the at least two galvanometers 110 are fused. It is beneficial to ensure the stability and accuracy of the scanning device.

It should be noted that in other embodiments of the present invention, the at least two galvanometer mirrors may also have different designed resonance frequencies. Since the quality factor Q is a dimensionless physical quantity that represents the damping property of the galvanometer, and also represents the size of the resonance frequency of the galvanometer with respect to the bandwidth, the upper limit of the difference between the resonance frequencies of the at least two galvanometers depends on f/Q, where , F is the resonance frequency of the galvanometer, and Q is the quality factor. It should be noted that, in this embodiment, the galvanometer 110 includes a MEMS galvanometer. By setting the galvanometer 110 as a MEMS galvanometer in the scanning device, the integration of the scanning device can be effectively improved, and the scanning frequency of the scanning device can be improved.

As shown in FIG. 1, the scanning device further includes at least one elastic connecting member 120, which is located between the moving parts 111 of two adjacent galvanometers 110, and is used to realize two adjacent Elastic connection between the moving parts 111 of the galvanometer 110.

Specifically, the elastic connecting member 120 can be elastically deformed, and two end portions 121 of the elastic connecting member 120 are respectively connected to the moving portions 111 of two adjacent galvanometers 110. When the two moving parts 111 connected by the same elastic connecting member 120 oscillate, since the two are elastically connected, the oscillations of the two moving parts 111 will merge into the same resonance mode at a certain phase after being stabilized. That is to say, even if the resonant mode frequencies of the two adjacent galvanometers 110 are different, the swings of the two moving parts 111 can be merged into the same resonant mode. The oscillating fusion is in the same resonance mode without increasing or even reducing the requirements on the assembly and processing accuracy of the two galvanometers 110, thereby achieving both cost reduction and performance improvement.

For example, the resonant frequencies of the two galvanometers 110 shown in FIG. 1 are 601 Hz and 602 Hz, respectively. Since the two galvanometers 110 are elastically connected through the elastic connecting member 120; when stabilized, the swing of the moving parts 110 of the two galvanometers 110 will merge into the same resonance mode, and the coupling The resonance frequency can be 601.5 Hz.

Moreover, when the swing amplitude of the two galvanometer mirrors 110 is α, since the light received by the scanning device is reflected by the reflective surfaces 111r of the two galvanometer mirrors 110 in turn, the light beam used for scanning is formed The angle of view is 4α.

In order to realize the function of elastic connection, the elastic connection member 120 can be elastically deformed under the action of external force. In this embodiment, the elastic connecting member 120 includes a spring, such as a coil spring, a spiral spring, or a spring leaf. In other embodiments of the present invention, the elastic connecting member 120 may also be a connecting structure supported by an elastic material.

In this embodiment, the elastic connecting member 120 and the moving part 111 are integrally manufactured, that is, during the processing of the galvanometer 110, the elastic connecting member 120 and the moving part 111 are manufactured at the same time. The manufacture of the elastic connecting member 120 is realized during the manufacturing process of the galvanometer 110, which can effectively improve the manufacturing accuracy of the elastic connecting member 120 and reduce the manufacturing cost.

For example, in some embodiments, the galvanometer includes a steel sheet, the steel sheet includes a torsion shaft and an inner frame connected thereto, and the inner frame as the moving part has a smooth surface as the reflecting surface and The reflective surface is opposite to the back; the galvanometer also includes a fixed connecting portion, the fixed portion is attached to the back; the elastic connecting member extends from one side of the fixed connecting portion and is connected to the fixed connecting portion. The connecting parts are integrally connected.

It should be noted that, in other embodiments of the present invention, the elastic connecting member may also be fixedly connected to the moving part, that is, the elastic connecting member and the galvanometer are separately manufactured and then fixedly connected. Specifically, the two ends of the elastic connecting member are respectively fixedly connected to the moving parts of the two adjacent galvanometers by clamping, welding, or the like. The elastic connecting member is manufactured separately from the galvanometer, so the manufacturing and setting of the elastic connecting member will not affect the process of the existing galvanometer.

The elastic connecting member can be manufactured integrally with the moving part; it can also be fixedly connected after the manufacturing is completed. The flexible arrangement of the elastic connecting member can effectively reduce the manufacturing cost of the scanning device.

Continuing to refer to FIG. 1, the at least two galvanometers 110 each have a rotating shaft 112, the moving part 111 swings around the rotating shaft 112, and the rotating shafts 112 of the at least two galvanometers 110 are arranged parallel to each other; the elastic connection The member 120 is arranged in a first plane (not shown in the figure) perpendicular to the rotating shaft 112, and the elastic connecting member 120 is elastically deformed in the first plane. Arranging the elastic connecting member 120 in the first plane can make the direction of elastic deformation of the elastic connecting member 120 lie in the first plane, so that the direction of elastic deformation of the elastic connecting member 120 is the same as the direction of elastic deformation. The swing directions of the at least two galvanometer mirrors 110 are matched to effectively realize the fusion of the same resonance mode.

It should be noted that in this embodiment, the moving part 111 is an axisymmetric structure with respect to the first plane, and the elastic connecting member 120 is elastically deformed in the first plane, thereby effectively ensuring stability. Later, the stability and reliability of the swing of the two moving parts 111 connected by the elastic connecting member 120 are beneficial to the improvement of the performance of the scanning device.

As shown in FIG. 1, the moving part 111 has at least one end surface (not marked in the figure) perpendicular to the reflecting surface 111r of the moving part 111; the two end parts 121 of the elastic connecting member 120 are connected to The end surfaces of the moving parts 110 of the two adjacent galvanometers 110 are connected.

In this embodiment, the rotation shafts 112 of the two adjacent galvanometers 110 define a second plane (not shown in the figure); the elastic connecting members 120 that connect the two adjacent galvanometers 110 The two ends 121 of are located on the same side of the second plane. As mentioned above, in this embodiment, the rotating shaft 112 is arranged perpendicular to the paper surface, so the second plane in FIG. 1 is perpendicular to the paper surface.

Specifically, the two moving parts 111 connected by the elastic connecting member 120 are arranged in a V shape. Therefore, in order to realize the connection between the moving parts 111 of the two galvanometers 110, in this embodiment, the elastic connecting member 120 is in any shape of a V-shape, a U-shape or an arc shape. The light 131 received by the scanning device and the light 133a or 133b formed after being sequentially reflected by the two galvanometer mirrors 110 are both located on the same side of the second plane. In addition, the two ends 121 of the elastic connecting member 120 connecting the two adjacent galvanometers 110 are located on the same side of the second plane defined by the rotating shaft 112 of the two adjacent galvanometers 110 .

It should be noted that, as shown in FIG. 1, in this embodiment, the galvanometer 110 is configured as a one-dimensional galvanometer, and the moving part 111 swings around a single shaft; the elastic connecting member 120 is connected to two Between the moving parts of the one-dimensional galvanometer. However, this approach is only an example. In other embodiments of the present invention, the galvanometer may also be configured as a two-dimensional galvanometer, and the elastic connecting member realizes the elastic connection between the moving parts of the two-dimensional galvanometer.

It should be noted that, in this embodiment, the two moving parts 111 connected by the elastic connecting member 120 are arranged in a V shape. However, this approach is only an example. In other embodiments of the present invention, according to different light path requirements, the elastic connecting member may also be arranged in other shapes.

Referring to FIG. 3, a schematic diagram of the optical path structure of the second embodiment of the technical solution of the present invention is shown.

This embodiment is the same as the previous embodiment, and the present invention will not be repeated here. The difference between this embodiment and the previous embodiment is that in this embodiment, the two moving parts 211 connected by the elastic connecting member 220 are arranged approximately in parallel.

Specifically, the two ends 221 of the elastic connecting member 220 connecting two adjacent galvanometers 210 are respectively located on the second plane defined by the rotating shafts 212 of the two adjacent galvanometers 210 On both sides. In this embodiment, the elastic connecting member 120 is set in any shape of a Z-shape or an S-shape to connect the moving parts 211 of the two galvanometers 210.

As shown in FIG. 3, in this embodiment, the light 231 received by the scanning device and the light 233a or 233b formed after being sequentially reflected by the two galvanometer mirrors 210 are respectively located on both sides of the second plane.

It should be noted that, as shown in FIGS. 1 and 3, in the first embodiment and the second embodiment, the number of galvanometer mirrors in the scanning device is two. However, this approach is only an example. In other embodiments of the present invention, the number of galvanometer mirrors in the scanning device may be more than two.

Referring to FIG. 4, a schematic diagram of the optical path structure of the third embodiment of the technical solution of the present invention is shown.

Specifically, the first galvanometer mirror 310a, the second galvanometer mirror 310b, and the third galvanometer mirror 310c are arranged opposite each other in sequence, and the light is reflected by the first galvanometer mirror 310a to the second galvanometer mirror 310b, Then, it is reflected by the second galvanometer 310b to the third galvanometer 310c.

In this embodiment, the scanning device includes at least two elastic connecting members 320, which are respectively located on the first galvanometer 310a and the second galvanometer 310b, and the second galvanometer 310b and the third galvanometer 310b. Between the galvanometer 310c. The two elastic connection members 320 respectively realize the elastic connection between the first galvanometer 310a and the second galvanometer 310b, and the second galvanometer 310b and the third galvanometer 310c. Therefore, after stabilization, the three galvanometers in this embodiment can be merged into the same resonance mode at a certain phase.

Therefore, when the swing amplitudes of the three galvanometer mirrors in the scanning device are all α, the field angle of the light 332 reflected by the first galvanometer mirror 310a is 2α under the premise that the incident direction of the received light 331 remains unchanged. The field angle of the light 333 reflected by the second galvanometer 310b is 4α, and the field angle of the light reflected by the third galvanometer 310c is 8α. It can be seen that by setting the number of galvanometers in the scanning device, the size of the field of view of the light used for scanning can be controlled to meet the requirements of various equipment.

Moreover, due to the arrangement of the elastic connecting member 320, even if multiple galvanometers are provided in the scanning device, the moving parts of the multiple galvanometers can still be oscillated in the same resonance mode, so there is no need to improve or even reduce the impact on the The machining and assembly precision requirements of the galvanometer.

Correspondingly, the present invention also provides a laser radar, including: a laser emitting device, a scanning device, and a receiving device. The scanning device is the scanning device provided by the present invention.

The laser emitting device includes a laser as a light source to generate laser light for detection. In this embodiment, the specific technical solution of the laser emitting device refers to the light source of the existing laser radar, which will not be repeated in the present invention.

The scanning device receives the light generated by the laser emitting device to form a scanning light. The scanning device is the scanning device provided by the present invention. For the specific technical solution of the scanning device, refer to the foregoing embodiment of the scanning device, and the present invention will not be repeated here.

The scanning device includes at least two galvanometers that are elastically connected by an elastic connecting member. Therefore, the moving parts of the two galvanometers can swing in the same resonance mode. Even if the resonance frequencies are different, the two connected The swing of the moving part of the galvanometer can be merged into the same resonant mode according to a certain phase, so that the swing of the moving part of the at least two galvanometers can be adjusted without increasing or even reducing the requirements for processing and assembly accuracy. A certain phase is merged into the same resonance mode to achieve the goal of both cost reduction and performance improvement.

Moreover, in some embodiments of the present invention, the reflective surfaces of the at least two galvanometers are arranged opposite to each other in sequence, and the light generated by the laser emitting device is projected to the scanning device, and is sequentially reflected on the reflective surface. Thereby changing the propagation direction; with the swing of the moving part, the changing angle of the propagation direction of the light reflected multiple times by the reflecting surfaces of the at least two galvanometer mirrors also increases, thereby effectively expanding the scanning device Form the field of view of the scanning light.

The scanning light formed by the scanning device is reflected by the target to be detected to form an echo light. The receiving device receives the echo light and performs photoelectric conversion on the echo light to form an electrical signal to realize detection. In this embodiment, the specific technical solution of the receiving device refers to the existing laser radar receiving device, which will not be repeated in the present invention.

Although the present invention is disclosed as above, the present invention is not limited to this. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

A scanning device, characterized by comprising:

At least two galvanometers arranged in sequence along the optical path, the galvanometer has a moving part, the moving part has a reflective surface suitable for reflecting light, and the galvanometer changes the reflection surface through the swing of the moving part. The propagation direction of the reflected light;

At least one elastic connecting member, the elastic connecting member has two ends, and the two ends are respectively connected to the moving parts of two adjacent galvanometers.
The scanning device according to claim 1, wherein the reflective surfaces of the at least two galvanometer mirrors are arranged opposite each other in sequence, so that the light rays are sequentially reflected on the reflective surfaces to change the propagation direction of the light rays .
3. The scanning device of claim 1, wherein the at least two galvanometer mirrors have the same designed resonance frequency.
The scanning device according to claim 1, wherein the elastic connecting member comprises a spring.
The scanning device according to claim 1, wherein the elastic connecting member and the moving part are integrally manufactured;

Alternatively, the elastic connecting member is fixedly connected to the moving part.
3. The scanning device according to claim 2, wherein the at least two galvanometers each have a rotation axis, the moving part swings around the rotation axis, and the rotation axes of the at least two galvanometer mirrors are arranged parallel to each other;

The elastic connecting member is arranged in a first plane perpendicular to the rotating shaft, and the elastic connecting member is elastically deformed in the first plane.
7. The scanning device according to claim 6, wherein the moving part has an axisymmetric structure with respect to the first plane.
8. The scanning device according to claim 6, wherein the moving part has at least one end surface perpendicular to the reflecting surface of the moving part;

The two end portions of the elastic connecting member are respectively connected with the end surfaces of the moving portions of two adjacent galvanometers.
8. The scanning device of claim 8, wherein the rotation axes of two adjacent galvanometer mirrors define a second plane;

The two ends of the elastic connecting member connecting the two adjacent galvanometers are located on one side of the second plane.
8. The scanning device of claim 8, wherein the rotation axes of two adjacent galvanometer mirrors define a second plane;

Two ends of the elastic connecting member connecting two adjacent galvanometers are respectively located on two sides of the second plane.
8. The scanning device according to claim 8, wherein the elastic connecting member has any shape of a V shape, a U shape, an arc shape, a Z shape or an S shape.
5. The scanning device of claim 1, wherein the galvanometer mirror comprises a MEMS galvanometer mirror.
8. The scanning device of claim 1, wherein the galvanometer is a one-dimensional galvanometer or a two-dimensional galvanometer.
A laser radar is characterized by comprising: a laser emitting device, a scanning device, and a receiving device, the scanning device being the scanning device according to any one of claims 1 to 13.