Scanning mirror drive device, optical scanning system, and lidar

Abstract

The application discloses a scanning mirror driving device, an optical scanning system and a laser radar, and belongs to the technical field of light detection and ranging. The scanning mirror driving device comprises a driving motor, the output shaft of the driving motor performs a circular motion during work; a motion adjusting component, the motion input end of the motion adjusting component is connected with the output shaft of the driving motor, the motion adjusting component is used for converting the circular motion input by the output shaft of the driving motor into reciprocating motion along a first preset direction; and the motion output end of the motion adjusting component is configured to be connected with a scanning mirror to be driven, so that the scanning mirror to be driven performs reciprocating motion in the first preset direction. The technical scheme of the application can reduce the performance requirement of the driving motor and reduce the implementation cost of the scanning mirror driving scheme.

Description

Technical Field

[0001] This application belongs to the field of optical detection and ranging technology, and particularly relates to a scanning mirror driving device, an optical scanning system and a lidar. Background Technology

[0002] An optical scanning system can realize optical detection and ranging functions. An optical scanning system usually has one or more scanning mirrors to reflect the light beam emitted by the light source to the target area. The scanning mirrors need to be driven to reciprocate in one or two directions to realize the reflected light beam scanning in the target area along the set direction. For example, when scanning in both the horizontal and vertical directions of the target area is required, the scanning mirrors need to be controlled to reciprocate in the horizontal and vertical directions respectively.

[0003] In existing technologies, the reciprocating motion of the scanning mirror is typically achieved by directly driving the scanning mirror with a drive motor. This direct-drive method maximizes the effective scanning time, but it requires the drive motor's drive shaft to quickly reverse direction after rotating in the forward direction, or vice versa. This rapid reversal process places extremely high demands on the drive motor's performance. Furthermore, to achieve high-precision scanning, a highly accurate angle sensing system is needed to measure the drive shaft's rotation angle and implement closed-loop control. Therefore, existing scanning mirror drive devices require high precision and performance from all components, while also incurring high implementation costs. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a scanning mirror driving device, an optical scanning system, and a lidar, which can reduce the performance requirements of the drive motor and reduce the implementation cost of the scanning mirror driving scheme.

[0005] In a first aspect, this application provides a scanning mirror driving device, comprising:

[0006] A drive motor, the output shaft of which performs circular motion during operation;

[0007] The motion adjustment component has its motion input end connected to the output shaft of the drive motor, and the motion adjustment component is used to convert the circular motion input from the output shaft of the drive motor into reciprocating motion along a first preset direction;

[0008] Furthermore, the motion output end of the motion adjustment component is configured to connect to the scanning mirror to be driven, so as to drive the scanning mirror to reciprocate in a first preset direction. The technical solution provided in this application, by including the motion adjustment component, converts the circular motion output by the drive motor along the same direction into reciprocating motion along a preset direction. This eliminates the need for rapid switching of the drive motor, thus eliminating the need for components such as an angle sensing system. The drive motor only needs to perform uniform circular motion in one direction, thereby reducing the requirements on the drive motor, achieving the need for device miniaturization, and reducing costs.

[0009] In some embodiments, the motion adjustment component includes a driving member and a driven member. The driving member is connected to the output shaft of the drive motor and performs circumferential motion along the axis of the output shaft under the drive of the output shaft.

[0010] The driven component and the driving component are configured to work together, and the driven component performs reciprocating motion along a first preset direction.

[0011] In some embodiments, the driven member is configured to be directly connected to the scanning mirror to be driven. This direct-drive approach effectively simplifies the device structure.

[0012] In some embodiments, the motion adjustment component further includes an output rod, with the follower connected to a first end of the output rod, and the second end of the output rod configured to be directly connected to the scanning mirror to be driven.

[0013] In some embodiments, the reciprocating motion along a first preset direction includes reciprocating motion along a straight line segment, and the follower is a linear motion follower.

[0014] Alternatively, in some other embodiments, the reciprocating motion along the first preset direction includes reciprocating motion within a central angle, and the follower is an oscillating follower.

[0015] The aforementioned motion adjustment components can be implemented using a cam structure or a four-bar linkage, as detailed below:

[0016] In some embodiments, the motion adjustment component is a cam mechanism, which includes a cam and a linear motion follower that are configured to cooperate. The rotation axis of the cam is coaxially arranged with the output shaft of the drive motor, and the linear motion follower is configured to drive the scanning mirror to be driven to reciprocate along a straight line segment.

[0017] In some embodiments, the motion adjustment component is a cam mechanism, which includes a cam and a swing follower that are configured to cooperate. The rotation axis of the cam is coaxially arranged with the output shaft of the drive motor, and the swing follower is configured to drive the scanning mirror to be driven to reciprocate within a central angle.

[0018] In some embodiments, the above-described four-bar linkage can be a crank-rocker structure, which includes a crank, a rocker, and a motion connecting rod. The rotation axis of the crank is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank is connected to the first end of the motion connecting rod, and the second end of the motion connecting rod is connected to the swing end of the rocker. The rotation axis of the crank and the fixed end of the rocker are fixed in position, and the rocker is configured to drive the scanning mirror to be driven to reciprocate within a central angle.

[0019] In some embodiments, the above-described four-bar linkage can be a crank-slider structure. The crank-rocker structure includes a crank, a motion connecting rod, a slider, and a fixed rod. The rotation axis of the crank is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank is connected to the first end of the motion connecting rod, and the second end of the motion connecting rod is connected to the slider. The slider is sleeved on the fixed rod and is configured to drive the scanning mirror to be driven to reciprocate along a straight line.

[0020] In some embodiments, the output shaft of the drive motor performs uniform circular motion or circular motion along a predefined speed curve during operation. This embodiment provides a scanning mirror drive device with the above-described structure, thereby reducing the drive requirements on the drive motor, simplifying the structure, reducing costs, and facilitating control of the drive motor.

[0021] Secondly, this application provides an optical scanning system, including a scanning mirror driving device and a scanning mirror. The scanning mirror driving device is used to drive the scanning mirror to reciprocate along a first preset direction, wherein the scanning driving device includes:

[0022] The drive motor's output shaft performs circular motion during operation.

[0023] The motion adjustment component has its motion input end connected to the output shaft of the drive motor. The motion adjustment component is used to convert the circular motion input from the output shaft of the drive motor into reciprocating motion along a first preset direction.

[0024] Furthermore, the motion output end of the motion adjustment component is configured to be connected to the scanning mirror to be driven, so as to drive the scanning mirror to be driven to reciprocate in a first preset direction.

[0025] The optical scanning mirror system has a scanning drive device with the aforementioned structure that drives the scanning mirror, causing it to reciprocate in a first preset direction. Because the scanning drive device includes a motion adjustment component, it converts the circular motion output by the drive motor along the same direction into reciprocating motion along a preset direction. This eliminates the need for rapid switching of the drive motor, thus eliminating the need for components such as angle sensing systems. The drive motor only needs to perform uniform circular motion in one direction, reducing the requirements on the drive motor, thereby achieving the goal of device miniaturization and cost reduction.

[0026] In some embodiments, the motion adjustment component includes a driving member and a driven member. The driving member is connected to the output shaft of the drive motor and performs circumferential motion along the axis of the output shaft under the drive of the output shaft.

[0027] The driven member is configured to cooperate with the aforementioned driving member and reciprocates along a first preset direction under the drive of the driving member.

[0028] In some embodiments, the aforementioned follower is configured to be directly connected to the scanning mirror to be driven.

[0029] In some embodiments, the motion adjustment component further includes an output rod, with the follower connected to a first end of the output rod and the second end of the output rod configured to be directly connected to the scanning mirror to be driven.

[0030] In some embodiments, the reciprocating motion along the first preset direction includes reciprocating motion along a straight line segment, and the follower is a linear motion follower.

[0031] In some embodiments, the reciprocating motion along the first preset direction includes reciprocating motion within a central angle, and the follower is an oscillating follower.

[0032] In some embodiments, the scanning mirror is disposed on a microelectromechanical system (MEMS), and the scanning mirror driving device is used to drive the MEMS to reciprocate along a first preset direction, so that the scanning mirror reciprocates along the first preset direction.

[0033] In some embodiments, a drive component provided on the microelectromechanical system can drive the scanning mirror to reciprocate along a second preset direction. The drive component cooperates with the scanning mirror drive device to drive the scanning mirror to scan along two different directions, thereby expanding the scanning area and meeting the needs of the application scenario.

[0034] Thirdly, embodiments of this application also provide a lidar including a light source, a photodetector, a processor, and the aforementioned optical scanning system, wherein the photodetector is configured to receive at least a portion of the reflected light from the target area and convert the at least a portion of the reflected light into an electrical signal, and the processor is configured to obtain a laser point cloud of the target area based on the electrical signal.

[0035] This application provides a scanning mirror driving device, an optical scanning system, and a lidar. In this scanning mirror driving device, the driving motor does not directly drive the scanning mirror. Instead, a motion adjustment component is added to the device. This motion adjustment component adjusts the motion mode. Its motion input end is connected to the output shaft of the driving motor. Specifically, the motion adjustment component converts the circular motion input from the driving motor's output shaft into reciprocating motion along a first preset direction, and outputs this reciprocating motion along the first preset direction at its motion output end. Specifically, the motion output end of the motion adjustment component can be configured to connect to the scanning mirror to be driven, thereby driving the scanning mirror to reciprocate along the first preset direction. This embodiment converts the unidirectional circular motion of the driving motor's output shaft into reciprocating motion of the scanning mirror along the first preset direction. In this embodiment, by converting the direct drive of the scanning mirror by the drive motor to an indirect drive method, high-precision scanning can be achieved without the need for an additional angle sensing system or closed-loop control. Furthermore, it eliminates the need for a drive motor that supports rapid reversal, allowing the use of a simpler stepper motor, thus reducing performance requirements and costs. Since it is not a direct drive method, a reasonable design of the motion adjustment components allows the drive motor and scanning mirror to be arranged side-by-side in the scanning system, reducing the overall height of the scanning system and facilitating the miniaturization of the device.

[0036] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0037] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0038] Figure 1 This is a schematic diagram of the structure of a scanning system in related technologies;

[0039] Figure 2 This is a schematic diagram of the structure of the scanning mirror driving device in some embodiments of this application;

[0040] Figure 3This is a schematic diagram of the structure of the scanning mirror driving device in some embodiments of this application;

[0041] Figure 4 This is a schematic diagram of the structure of the scanning mirror driving device in some embodiments of this application;

[0042] Figure 5 This is a schematic diagram of reciprocating motion in some embodiments of this application;

[0043] Figure 6 This is a schematic diagram of reciprocating motion in some embodiments of this application;

[0044] Figure 7 This is a schematic diagram of the structure of the motion adjustment component implemented by the cam mechanism in some embodiments of this application;

[0045] Figure 8 This is a schematic diagram of the structure of the motion adjustment component implemented by the cam mechanism in some embodiments of this application;

[0046] Figure 9 This is a schematic diagram of the motion adjustment component implemented using a four-bar linkage in some embodiments of this application;

[0047] Figure 10 This is a schematic diagram of the motion adjustment component implemented using a four-bar linkage in some embodiments of this application;

[0048] Figure 11 This is a schematic diagram of the structure of the optical scanning system in some embodiments of this application;

[0049] Figure 12 for Figure 11 A schematic diagram of the scanning mirror in the embodiment;

[0050] Figure 13 The diagram shows the structure of the lidar in some embodiments of this application;

[0051] Figure 14 This is a schematic diagram of the structure of the lidar in some embodiments of this application. Detailed Implementation

[0052] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0053] In technologies such as lidar that possess optical detection and ranging capabilities, an optical scanning system is typically used. This optical scanning system includes a scanning mirror drive device and a scanning mirror. The main function of the scanning mirror drive device is to drive the scanning mirror to reciprocate along a set direction. At this time, the scanning mirror can reflect the laser beam incident on its mirror surface and make the reflected beam scan a target area at a certain frequency, thereby achieving the purpose of incident laser beams on the target area that the lidar needs to detect. The lidar's optical receiver can receive the reflected beam from the target area and perform object detection and ranging functions based on the reflected beam.

[0054] In related technologies, the aforementioned scanning mirror driving device mainly includes a drive motor. The drive motor directly drives the scanning mirror to reciprocate along a set direction. However, because reciprocating motion is required, the drive motor needs to continuously reverse when reaching a preset angle. This necessitates, on the one hand, adding a high-precision angle sensing system to measure the rotation angle of the drive motor's output shaft, ensuring timely reversal upon reaching the preset angle, and adding closed-loop control during this process. On the other hand, the drive motor needs to have excellent performance to quickly switch rotation directions when reversal is required; only a high-performance drive motor can achieve rapid reversal. These performance requirements and the addition of a high-precision angle sensing system both increase the cost of the scanning drive device. Furthermore, when using the aforementioned scanning mirror driving device in an optical scanning system, the output shaft of the drive motor directly drives the scanning mirror. Therefore, during the assembly of the scanning drive device… Figure 1 This is a schematic diagram of the structure of a scanning system in related technologies, such as... Figure 1 As shown, the drive motor 11 and the scanning mirror 12 are stacked in the extension direction of the output shaft of the drive motor. In addition, the height of the mounting base 13 of the drive motor 11 will result in an excessively large scanning system, which is not conducive to achieving the design requirement of miniaturization of the device.

[0055] This application provides a scanning mirror driving device. Instead of directly driving the scanning mirror with a drive motor, a motion adjustment component is added to the device. This component adjusts the motion mode. Its input end is connected to the output shaft of the drive motor. Specifically, the motion adjustment component converts the circular motion input from the drive motor's output shaft into reciprocating motion along a first preset direction and outputs this reciprocating motion along the first preset direction at its output end. Specifically, the output end of the motion adjustment component can be configured to connect to the scanning mirror to be driven, thereby driving the scanning mirror to reciprocate along the first preset direction. This embodiment converts the circular motion of the drive motor's output shaft into reciprocating motion of the scanning mirror along the first preset direction. In this embodiment, by converting the direct drive of the scanning mirror by the drive motor to an indirect drive method, high-precision scanning can be achieved without the need for an additional angle sensing system or closed-loop control. Furthermore, it eliminates the need for a drive motor that supports rapid reversal, allowing the use of a simpler stepper motor, thus reducing performance requirements and costs. Since it is not a direct drive method, a reasonable design of the motion adjustment components allows the drive motor and scanning mirror to be arranged side-by-side in the scanning system, reducing the overall height of the scanning system and facilitating the miniaturization of the device.

[0056] Figure 2 This is a schematic diagram of the structure of the scanning mirror driving device in some embodiments of this application, such as... Figure 2 As shown, the scanning mirror driving device includes a drive motor 21 and a motion adjustment component 22. The output shaft of the drive motor 21 performs circular motion during operation. The drive motor 21 can be selected from various types of motors, such as stepper motors. The motion adjustment component 22 has the ability to adjust the motion mode. Specifically, the motion input end 221 of the motion adjustment component 22 is connected to the output shaft 211 of the drive motor 21 and can convert the circular motion input by the output shaft 211 of the drive motor 21 into reciprocating motion along a first preset direction. The reciprocating motion along the first preset direction is output through the motion output end 222 of the motion adjustment component 22.

[0057] In this embodiment of the application, the motion output terminal 222 of the motion adjustment component 22 can be configured to be connected to the scanning mirror to be driven, so that the motion output terminal 222 of the motion adjustment component 22 can drive the scanning mirror to be driven to reciprocate along a first preset direction.

[0058] In the embodiments of this application, the motion adjustment component may include various implementation methods, but in terms of functionality, the motion adjustment component 22 may mainly include two components, namely, an active component and a passive component. The active component realizes the function of the motion input end in the above embodiments, and the passive component realizes the function of the motion output end. The active component and the passive component can be used in conjunction.

[0059] Figure 3 This is a schematic diagram of the structure of the scanning mirror driving device in some embodiments of this application, such as... Figure 3 As shown, among them Figure 2 The motion adjustment component 22 further includes a driving element 31 and a driven element 32, and the driving element 31 can be connected to the output shaft of the drive motor, optionally, as... Figure 4 As shown, the active member 31 may include a rotating shaft 311, which may be coaxially arranged with the output shaft of the drive motor, so that the active member 31 can perform circular motion synchronously with the output shaft of the drive motor during operation. Then, inside the motion adjustment component, by cooperating the active member 31 and the driven member 32, the active member 31 can not only drive the driven member 32 to move, but also drive the driven member 32 to perform reciprocating motion along a first preset direction.

[0060] Those skilled in the art can design the mechanical structure of the motion adjustment component 22 based on the above-described functional requirements, so that the driving component 31 and the driven component 32 can achieve the corresponding functions. Some specific implementation methods will also be provided in the subsequent embodiments of this application.

[0061] In some embodiments, the driven member 32, driven by the driving member 31, can perform reciprocating motion along a first preset direction, and can then be connected to the scanning mirror 34 to be driven, thereby driving the scanning mirror 34 to reciprocate in the first preset direction. In specific implementations, the output end of the driven member 32 of the motion adjustment component can be configured to be directly connected to the scanning mirror 34 to be driven; or, as... Figure 4 As shown, for Figure 2 The motion adjustment component 22 in the middle includes, in addition to Figure 3 In addition to the driving member 31 and the driven member 32 shown, an output rod 33 may also be included. In this case, the output end of the driven member 32 is connected to the first end of the output rod 33, and the second end of the output rod 33 is configured to be directly connected to the scanning mirror 34 to be driven. The output rod 33 can be of various shapes, such as a straight line, a ring, or a broken line. During operation, the entire output rod 33 will reciprocate along the first preset direction together with the output end of the driven member 32, and the output rod 33 will drive the scanning mirror 34 to perform the same reciprocating motion along the first preset direction.

[0062] In this embodiment of the application, the reciprocating motion along the first preset direction can include a variety of different situations, such as reciprocating motion along a straight line segment or reciprocating motion within a central angle.

[0063] Figure 5 This is a schematic diagram of reciprocating motion in some embodiments of this application, such as... Figure 5 As shown, it can be the reciprocating motion of the center point of the scanning mirror 34 between points A and B along a straight line segment, and the placement direction of the scanning mirror 34 can be at a preset angle α with the straight line segment during the scanning process. α can be 90° or other acute angles. In this embodiment, the first preset direction includes both the direction from A to B and the direction from B to A. The scanning mirror 34 is driven to move from point A to point B and then from point B to point A within one cycle, thereby achieving scanning of the reflected light beam within a preset area. In some embodiments, the driven member can be directly connected to the center point of the scanning mirror 34, or... Figure 4 The second end of the output rod 33 is directly connected to the center point of the scanning mirror 34, thereby driving the scanning mirror 34 to perform the reciprocating motion along a straight line segment.

[0064] Figure 6 This is a schematic diagram of reciprocating motion in some embodiments of this application, such as... Figure 6 As shown, one end of the scanning mirror 34 can be fixed, for example, at point O. The scanning mirror 34 is then driven to reciprocate along a central angle β centered at point O, where β is defined by the radii OX and OY passing through the center O. Within one cycle, the scanning mirror 34 is driven to move along OX to OY, and then from OY back to OX, thereby scanning the reflected light beam within a preset area. In some embodiments, one end of the scanning mirror 34 can be fixed at point O, or it can be a follower or... Figure 4 The second end of the output rod 33 can be connected to other positions on the scanning mirror 34 except for point O, such as the other end C of the scanning mirror 34, or the center point of the scanning mirror 34, so as to drive the scanning mirror 34 to reciprocate within the central angle of angle β.

[0065] The motion adjustment component in the above embodiments of this application can be implemented using a cam mechanism or a four-bar linkage. When using a cam mechanism, the driving element is a cam, and the driven element can be a linear motion driven element or a swing driven element.

[0066] Specifically, the reciprocating motion along the first preset direction described in the above embodiments can be a reciprocating motion along a straight line segment or a reciprocating motion within a central angle, i.e., a reciprocating rotation around a fixed point. Corresponding to the above two cases, the follower in this application embodiment can be a linear motion follower or a oscillating follower. In this application embodiment, whether it is a linear motion follower or an oscillating follower, it can achieve the above-mentioned reciprocating motion along the first preset direction. This can be achieved by designing a corresponding contour curve on the cam, and then the above-mentioned linear motion follower or oscillating follower contacts the surface of the cam, thereby converting the cam's circular motion into the cam's reciprocating motion along a straight line segment or a reciprocating motion within a central angle. In addition, in some embodiments, elastic components such as springs can be provided at the contact position between the linear motion follower or oscillating follower and the cam to achieve both close contact and effective reduction of wear and tear.

[0067] In some embodiments, such as Figure 7 As shown, it provides a technical solution for realizing a linear motion follower using a push rod, such as... Figure 7 As shown, and in combination Figure 5 or Figure 6 The motion adjustment component includes a cam 51 and a push rod 52. The push rod 52 is a linear motion follower, confined within a linear limiter 53. This linear limiter 53 restricts the push rod 52 to move only along a straight line segment, preventing oscillations in other directions. During the rotation of the cam 51 around its axis, it continuously pushes the push rod 52 to reciprocate along a straight line segment. The push rod 52 is fixedly connected to the scanning mirror 34, for example, by connecting one end of the push rod 52 to... Figure 5 When the center point of the scanning mirror 34 is connected, or the scanning mirror 34 is fixed on the push rod 52 to form an integral structure, or the scanning mirror 34 is fixed to the push rod 52 through other intermediate fixed connection structures, but the scanning mirror 34 is located outside the plane where the cam 51 and the push rod 52 are located, the push rod 52 can drive the scanning mirror 34 to reciprocate along a straight line segment. Furthermore, the motion law of the push rod 52 when reciprocating along the straight line segment can be adjusted by designing the contour curve of the cam 51. When the push rod 52 and the scanning mirror are connected, the contour curve of the cam can be designed according to the specific requirements of the motion law of the scanning mirror during operation.

[0068] Optional, such as Figure 7 As shown, a rotating disk 55 can be provided at the end of the push rod 52 that contacts the cam 51. During the rotation of the cam 51, the rotating disk 55 will rotate while pushing the push rod 52 to reciprocate along a straight line segment. Due to the rotating disk 55, the wear between the push rod 52 and the cam 51 can be effectively reduced.

[0069] In some embodiments, such as Figure 8 As shown, it provides a technical solution for driving a scanning mirror to reciprocate in a first preset direction using a oscillating follower, such as... Figure 8 As shown, the motion adjustment component includes a cam 51, a swing rod 54, and a rotating disk 55. The swing rod 54 and the rotating disk 55 form a swing follower. One end of the swing rod 54 is fixed at a center O, and the other end is connected to the rotating disk 55. The edge of the rotating disk 55 abuts against the cam 51. The rotation axis of the rotating disk 55 is fixed to the swing rod 54, so that when the cam 51 rotates along its rotation axis, it can push the rotating disk 55 and the swing rod 54 to rotate around the center O, and can form a rotation angle. This is achieved by fixing the swing rod 54 to the scanning mirror 34, for example, by connecting one end of the swing rod 54 and... Figure 6 The scanning mirror 34 shown can be connected at one end C, or the scanning mirror 34 can be fixed to the swing rod 54 as a single unit, or the scanning mirror 34 can be fixed to the swing rod 54 through other intermediate fixed connection structures, but the scanning mirror 34 is located outside the plane where the cam 51 and the swing rod 54 are located. In all these cases, the swing rod 54 can drive the scanning mirror 34 to reciprocate within a central angle. Furthermore, the specific rotation angle and the motion law requirements of the swing follower composed of the rotating wheel 55 and the swing rod 54 can be obtained by designing the contour curve of the cam 51.

[0070] In some embodiments, the motion adjustment component described above may also be a four-bar linkage structure, which can convert circular motion into reciprocating motion within a central angle, or reciprocating motion along a straight line segment.

[0071] Specifically, when using a four-bar linkage to convert circular motion into reciprocating motion within a central angle, the aforementioned four-bar linkage can be a crank-rocker structure, where the crank acts as the driving element, and the rocker can be used as the oscillating driven element. For example... Figure 9 As shown, the provided crank-rocker structure includes a crank 61, a rocker arm 62, and a motion connecting rod 63. The rotation axis of the crank 61 is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank 61 is connected to the first end of the motion connecting rod 63, and the second end of the motion connecting rod 63 is connected to the swing end of the rocker arm 62. The rotation axis of the crank 61 and the fixed end of the rocker arm 62 are fixed in position, and the fixed point of the rocker arm 62 is point O. In some embodiments, a fixed connecting rod 60 can be provided to fix the position of the rotation axis and the fixed end of the rocker arm 62. Alternatively, when the above-mentioned four-bar linkage structure is fixed on the mounting bracket, the position of the rotation axis of the crank 61 and the fixed end of the rocker arm 62 is fixed on the mounting bracket, and the mounting bracket is used as a fixed connecting rod, so the fixed connecting rod 60 can be omitted.

[0072] When the aforementioned crank-rocker structure is in operation, because the rotation shaft of the crank 61 and the output shaft of the drive motor are coaxially arranged, it can perform circular motion synchronously with the output shaft of the drive motor. During the circular motion of the crank 61, it can drive the swing end of the rocker arm 62 to perform reciprocating motion through the motion connecting rod 63, causing it to reciprocate within a central angle β centered at point O. In some embodiments, by fixing the rocker arm 62 to the scanning mirror 34, for example, it can be... Figure 6 The scanning mirror 34 is fixed to the rocker arm 62, or the rocker arm 62 is part of the scanning mirror 34 and the two are an integral structure, or the scanning mirror 34 is fixed to the rocker arm 62 through other intermediate fixed connection structures, but the scanning mirror 34 is located outside the plane where the crank 61 and the rocker arm 62 are located. In all these cases, the reciprocating motion of the scanning mirror 34 to be driven can be realized during the operation of the crank-rocker structure.

[0073] In some embodiments, the crank-rocker structure described above can be modified to obtain a crank-slider structure. This crank-slider structure is used to convert circular motion into reciprocating motion along a straight line segment. In this crank-slider structure, the crank acts as the driving member, and the slider acts as the driven member for linear motion. Figure 10 As shown, the provided crank-slider structure includes a crank 61, a motion connecting rod 63, a slider 64, and a fixed rod 65. The rotation axis of the crank 61 is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank 61 is connected to the first end of the motion connecting rod 63, and the second end of the motion connecting rod 63 is connected to the slider 64. The slider 64 can be sleeved on the fixed rod 65 or disposed inside the fixed rod 65, as long as the slider 64 can move along a straight segment along the length of the fixed rod 65. For example... Figure 10 The straight line segment L shown, and the slider 64 can be configured with the line segment to be driven. Figure 5 The scanning mirror 34 is fixedly connected to achieve reciprocating motion of the driving scanning mirror 34 within a straight line segment. In the above embodiments of this application, the crank-slider structure, during operation, allows the crank 61 to rotate synchronously with the output shaft of the drive motor because the crank 61's rotation axis and the drive motor's output shaft are coaxially arranged. During the crank 61's circular motion, it can drive the slider 64 to reciprocate within the straight line segment AB via the motion connecting rod 63. In some embodiments, by fixing the slider 64 to the scanning mirror 34, for example, the slider 64 can be... Figure 5The scanning mirror 34 can be fixed to the slider 64, or the slider 64 can be used as part of the scanning mirror 34 to be driven, with the two forming an integral structure. Alternatively, the scanning mirror 34 can be fixed to the slider 64 through other intermediate fixed connection structures, but the scanning mirror 34 is located outside the plane where the crank 61 and the slider 64 are located. All these situations enable the reciprocating motion of the scanning mirror 34 to be driven to be realized during the operation of the crank-slider structure.

[0074] In the above embodiments of this application, motion mode adjustment is achieved by using a cam structure or a four-bar linkage structure, adjusting the circular motion to a reciprocating motion along a straight line segment, or a reciprocating motion within a central angle. This allows the beam to be projected in a scanning manner within the target area even when the output shaft of the drive motor only outputs circular motion. Therefore, it eliminates the need for a costly drive motor capable of rapid reversal, as well as additional angle detection and closed-loop control systems, thereby reducing costs. In some embodiments, the output shaft of the drive motor can perform uniform circular motion during operation. In this case, the required reciprocating motion operating characteristics are obtained by designing the motion adjustment components. Alternatively, the speed curve of the circular motion can be predefined according to the required reciprocating motion operating characteristics, so that by controlling the operation of the drive motor, the output shaft of the drive motor can perform circular motion along the predefined speed curve.

[0075] This application also provides an optical scanning system. Figure 11 This is a schematic diagram of the structure of an optical scanning system according to an embodiment of this application, such as... Figure 11 As shown, the optical scanning system includes a scanning mirror driving device 71 and a scanning mirror 72, wherein the scanning mirror driving device 71 can adopt the above-mentioned... Figures 2-10 In any embodiment of the scanning mirror driving device, the scanning mirror driving device 71 is used to drive the scanning mirror 72 to reciprocate along a first preset direction. Specifically, the scanning mirror driving device 71 includes not only a drive motor 711, whose output shaft performs circular motion during operation, but also a motion adjustment component 712. The motion input end of the motion adjustment component 712 is connected to the output shaft of the drive motor, which can convert the circular motion input from the output shaft of the drive motor into reciprocating motion along the first preset direction. The output end of the motion adjustment component is configured to be connected to the scanning mirror 72 to be driven, so that the scanning mirror 72 can be driven to reciprocate along the first preset direction.

[0076] The optical scanning system provided in this application embodiment can convert the circular motion output by the drive motor output shaft into reciprocating motion that drives the scanning mirror to move along a first preset direction. This eliminates the need for the drive motor to have rapid reversal capability, thus reducing the performance requirements of the drive motor. Furthermore, it eliminates the need for an angle sensing system to quickly and accurately detect the rotation angle of the drive motor's output shaft, reducing the need for closed-loop control and significantly lowering costs. Additionally, compared to existing technologies such as… Figure 1 In the technical solution shown that the scanning mirror is directly driven by the drive motor, the drive motor and the scanning mirror need to be stacked. In the technical solution provided by the embodiment of this application, the motion adjustment component can also offset the position of the rotation axis of the circular motion from the position of the reciprocating motion in the first preset direction during the motion mode conversion process, so that the scanning mirror can be set side by side with the drive motor. At this time, the height of the entire scanning system can be reduced, thereby simplifying the height of the scanning system and facilitating the miniaturization of the device.

[0077] In a scanning system, the aforementioned scanning mirror can be a mirror with reflective function, and the scanning mirror driving system can drive the mirror to reciprocate, thereby adjusting its scanning range. Figure 12 This is a schematic diagram of the scanning mirror structure in an embodiment of this application, as shown below. Figure 12 As shown, the scanning mirror 72 can be disposed on the microelectromechanical system 70. It can be a single mirror disposed on the microelectromechanical system, or multiple mirrors disposed on the microelectromechanical system, with the multiple mirrors together forming a scanning mirror. Optionally, a reflector can be formed on the surface of the microelectromechanical system by coating.

[0078] Furthermore, the aforementioned scanning mirror can scan along a first preset direction under the drive of the scanning mirror driving device. In the scanning requirements of the scanning system, scanning in two different directions is typically needed, such as scanning along the first preset direction and scanning along a second preset direction. This allows the final reflected beam of the scanning mirror to complete scanning in both horizontal and vertical directions within the target area. Optionally, if the first and second preset directions are both reciprocating motions along a straight line segment, then the straight line direction can be respectively along... Figure 12 The directions of the x-axis and y-axis are shown; if the first preset direction and the second preset direction mentioned above are both reciprocating motions along a circumferential angle, then the angular velocity vector of rotation during the reciprocating motion is in the x-axis and y-axis directions respectively, which can ultimately reflect the laser beam onto the target area and scan the target area.

[0079] For the aforementioned scanning along the second preset direction, a driving component can be set on a microelectromechanical system (MEMS), and the driving component on the MEMS can drive the scanning mirror to reciprocate along the second preset direction. In a specific embodiment, multiple mirrors can be formed on the MEMS, and the multiple mirrors together form a scanning mirror. The driving component is divided into multiple driving units, and each mirror is provided with a corresponding driving unit. Each driving unit synchronously drives the corresponding mirror to drive the scanning mirror to reciprocate along the second preset direction.

[0080] This application also discloses a lidar that can perform light detection and ranging functions. Figure 13 The following are schematic diagrams of the lidar structure in some embodiments of this application, such as... Figure 13 As shown, the lidar includes a light source 81, a photodetector 82, and the aforementioned optical scanning system 83. The laser beam emitted by the light source 81 is reflected by the scanning mirror of the optical scanning system 83 to the target area M. The photodetector 82 is configured to receive at least a portion of the reflected light from the target area M and convert the reflected light into an electrical signal. Furthermore, when a processor is also provided in the system, the processor can be configured to obtain the laser point cloud of the target area based on the electrical signal output by the photodetector, thereby realizing optical ranging and detection functions.

[0081] Figure 14 The following are schematic diagrams of the lidar structure in some embodiments of this application, such as... Figure 14 As shown, the lidar also includes a light source 81, a photodetector 82, and an optical scanning system 83, the difference being that, unlike the aforementioned... Figure 13 The technology used in China differs from that of the rangefinder. Figure 14 In the illustrated embodiment, a coaxial technical solution is adopted. Specifically, it also includes a beam splitter 84, so that the laser beam emitted by the light source 81 passes sequentially through the beam splitter 84 and the scanning mirror of the optical scanning system 83, and is reflected by the scanning mirror to the target area M for scanning. At least part of the reflected light from the target area M can then pass through the scanning mirror of the optical scanning system 83 to the beam splitter 84, and the beam splitter 84 guides the reflected light to the photodetector 82, so that the photodetector 82 can convert the reflected light into an electrical signal. Furthermore, when a processor is also provided in the system, the processor can be configured to obtain the laser point cloud of the target area based on the electrical signal output by the photodetector, thereby realizing optical ranging and detection functions. The light source 81, photodetector 82 and beam splitter 84 in this embodiment can also constitute a laser transceiver module to realize laser emission and detection.

[0082] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0083] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0084] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0085] In the description of this application, "multiple" means two or more.

[0086] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0087] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0088] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0089] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A scanning mirror driving device, characterized in that, include: A drive motor, the output shaft of which performs circular motion during operation; A motion adjustment component includes a driving member and a driven member. The driving member is connected to the output shaft of the drive motor and performs circumferential motion along the axis of the output shaft under the drive of the output shaft. The driven member is configured to cooperate with the driving member and performs reciprocating motion along a first preset direction under the drive of the driving member. The driven member is configured to be connected to a scanning mirror to be driven, so as to drive the scanning mirror to perform reciprocating motion in the first preset direction.

2. The scanning mirror driving device according to claim 1, characterized in that, The motion adjustment component also includes an output rod, the driven member is connected to a first end of the output rod, and the second end of the output rod is configured to be directly connected to the scanning mirror to be driven.

3. The scanning mirror driving device according to claim 1, characterized in that, The reciprocating motion along the first preset direction includes reciprocating motion along a straight line segment, and the driven member is a linear motion driven member.

4. The scanning mirror driving device according to claim 1, characterized in that, The reciprocating motion along the first preset direction includes reciprocating motion within a central angle, and the driven member is an oscillating driven member.

5. The scanning mirror driving device according to any one of claims 1-4, characterized in that, The motion adjustment component is a cam structure or a four-bar linkage structure.

6. The scanning mirror driving device according to claim 5, characterized in that, The cam mechanism includes a cam and a linear motion follower that are configured to work together. The rotation axis of the cam is coaxial with the output shaft of the drive motor. The linear motion follower is configured to drive the scanning mirror to be driven to reciprocate along a straight line segment.

7. The scanning mirror driving device according to claim 6, characterized in that, One end of the linear motion follower is provided with a rotating disk, which makes rolling contact with the cam.

8. The scanning mirror driving device according to claim 5, characterized in that, The cam mechanism includes a cam and a swing follower that are configured to work together. The rotation axis of the cam is coaxial with the output shaft of the drive motor. The swing follower is configured to drive the scanning mirror to be driven to reciprocate within a central angle.

9. The scanning mirror driving device according to claim 5, characterized in that, The four-bar linkage includes a crank, a rocker arm, and a motion connecting rod. The rotation axis of the crank is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank is connected to the first end of the motion connecting rod, and the second end of the motion connecting rod is connected to the swing end of the rocker arm. The rotation axis of the crank and the fixed end of the rocker arm are fixed in position. The rocker arm is configured to drive the scanning mirror to be driven to reciprocate within a central angle.

10. The scanning mirror driving device according to claim 5, characterized in that, The four-bar linkage consists of a crank, a motion connecting rod, a slider, and a fixed rod. The rotation axis of the crank is coaxially arranged with the output shaft of the drive motor. The circumferential motion end of the crank is connected to the first end of the motion connecting rod, and the second end of the motion connecting rod is connected to the slider. The slider is sleeved on the fixed rod and is configured to drive the scanning mirror to be driven to reciprocate along a straight line.

11. An optical scanning system, characterized in that, It includes a scanning mirror driving device and a scanning mirror, wherein the scanning mirror driving device is the scanning mirror driving device according to any one of claims 1-10, and the driven member is connected to the scanning mirror.

12. The optical scanning system according to claim 11, characterized in that, The scanning mirror is mounted on the microelectromechanical system (MEMS), and the scanning mirror driving device is used to drive the MEMS to reciprocate along a first preset direction, so that the scanning mirror reciprocates along the first preset direction.

13. The optical scanning system according to claim 12, characterized in that, The microelectromechanical system includes a driving component that drives the scanning mirror to reciprocate along a second preset direction.

14. A lidar, characterized in that, The system includes a light source, a photodetector, a processor, and an optical scanning system according to any one of claims 11-13, wherein a laser beam emitted by the light source is reflected by a scanning mirror of the optical scanning system to a target area, the photodetector is configured to receive at least a portion of the reflected light from the target area and convert the at least a portion of the reflected light into an electrical signal, and the processor is configured to obtain a laser point cloud of the target area based on the electrical signal.

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