Galvanometer and laser radar
By introducing connecting beams into the MEMS galvanometer to disperse torsional shaft stress, the problem of torsional shaft prone to fatigue and fracture is solved, and the reliability and service life of the equipment are improved.
Patent Information
- Application Number
- CN202421522062.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-28
- Publication Date
- 2025-08-05
- Estimated Expiration
- 2034-06-28
AI Technical Summary
When the MEMS galvanometer swings quickly or swings at a large angle, the torsional shaft is prone to fatigue and breakage, resulting in a decrease in equipment reliability.
A galvanometer structure is designed, wherein the base includes a first connecting beam, one end of the torsion shaft is connected to the mirror module, and the other end is connected to the connecting beam, and the stress of the torsion shaft is dispersed through the connecting beam, thereby reducing stress concentration.
Effectively alleviate the stress concentration of the torsion shaft, reduce the risk of fatigue and fracture of the torsion shaft, and improve the reliability and service life of the equipment.
Smart Images
Figure CN223193119U_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present application relate to the technical field of MEMS devices, and in particular to a galvanometer and a laser radar. Background Art
[0002] LiDAR is a radar system that uses laser beams to detect the position, speed, and other characteristic quantities of a target. In related technologies, a LiDAR with a scanning function includes a housing, a transmitting module, a receiving module, and a scanning module. The transmitting module is used to transmit detection light to detect the target object, and the receiving module is used to receive the echo light formed by the detection light reflected by the target object. The scanning module is arranged on the optical path of the detection light and the echo light. It is used to receive the detection light emitted by the transmitting module and deflect it outside the LiDAR, thereby forming a specific detection field of view outside the LiDAR to detect the target object. In addition, the scanning module is also used to receive the echo light reflected by the target object and deflect it to the receiving module so that the receiving module receives the echo light.
[0003] Related technologies use a galvanometer, such as a micro-electromechanical system (MEMS) galvanometer, as a scanning module. The galvanometer includes a movable reflector that can swing in one or two directions under the action of a driving force, so that the detection light is emitted through the reflector at different times at different angles, thereby enabling the detection light to form the above-mentioned detection field of view outside the lidar.
[0004] At present, the MEMS oscillating mirror includes a base, a swingable reflector module and a torsion axis. A through groove is formed in the middle of the base, the reflector module is arranged in the through groove and is connected to the base through the torsion axis, so that the reflector module can swing relative to the base, thereby realizing the above-mentioned function. Utility Model Content
[0005] In related art, a galvanometer consists of a base, a reflector module, and a torsion shaft. The torsion shaft is connected to both sides of the reflector module and is connected to the base, allowing the reflector module to swing relative to the base around the axis of the torsion shaft. When the reflector module swings rapidly or at a large angle, the torsion shaft is subjected to significant stress, making it susceptible to fatigue fracture.
[0006] The embodiments of the present application provide a galvanometer and a laser radar, which can improve the current situation where when the reflector module swings rapidly or at a large angle, the torsion axis is subjected to large stress and is prone to fatigue fracture.
[0007] The galvanometer includes a base, a reflector module, and two first torsion axes. The base includes a first main body and a first connecting beam. The first main body is provided with a first through-groove extending along a first direction. The first connecting beam is provided in the first through-groove. Both ends of the first connecting beam are respectively connected to the first main body, and the first through-groove is divided into a first groove and a second groove arranged along a second direction. The second direction is perpendicular to the first direction. The reflector module is provided in the first groove for reflecting a light beam. The two first torsion axes are along the second direction, and the two first torsion axes are respectively provided on both sides of the reflector module. One end of the first torsion axis is connected to the reflector module, and the other end extends along the second direction to connect with the base. The first torsion axis located between the reflector module and the first connecting beam is connected to the first connecting beam.
[0008] Optionally, the base includes two first connecting beams, the two first connecting beams dividing the first through slot into the first slot and two second slots, and along the second direction, the two second slots are respectively located on both sides of the first slot. Each first torsion axis is correspondingly connected to one of the first connecting beams.
[0009] Optionally, the first connecting beam has a first surface and a second surface disposed opposite each other along the first direction, the first surface and a surface of the reflector module for reflecting the light beam being located on the same side of the base, and one of the first surface and the second surface is provided with a plurality of first grooves spaced apart along a third direction, wherein the third direction is the extension direction of the first connecting beam.
[0010] Optionally, the first surface is provided with the first groove, and the second surface is provided with a plurality of second grooves spaced apart along the third direction.
[0011] Optionally, the relationship between the first groove and the second groove satisfies at least one of the following conditions: a) the projections of the first groove and the second groove along the first direction are alternately arranged, and the projection of a first groove along the first direction is completely staggered with the projection of an adjacent second groove along the first direction; b) along the first direction, the sum of the depths of the first groove and the second groove is less than the thickness of the first connecting beam.
[0012] Optionally, the galvanometer is a two-dimensional galvanometer, and the reflector module includes an inner frame, a reflector, and two second torsion shafts. The inner frame is disposed between and connected to the two first torsion shafts, respectively. The inner frame is provided with a second through-slot extending along the first direction. The reflector is disposed in the second through-slot and is configured to reflect a light beam. The two second torsion shafts are disposed in the second through-slot and are disposed on either side of the reflector along a fourth direction. One end of the second torsion shaft is connected to the reflector, and the other end extends along the fourth direction to connect to the inner frame. The first direction, the second direction, and the fourth direction are perpendicular to each other.
[0013] Optionally, the inner frame includes a second main body and two second connecting beams. The second main body is provided with a second through-slot. The second connecting beam is disposed in the second through-slot, with both ends of the second connecting beam respectively connected to the second main body. The two second connecting beams divide the second through-slot into a third slot arranged along the fourth direction and two fourth slots, with the two fourth slots located on either side of the third slot. The reflector is disposed in the third slot, and each second torsion axis is connected to a corresponding second connecting beam.
[0014] Optionally, the second connecting beam has a third surface and a fourth surface disposed opposite each other along the first direction, the third surface and a surface of the reflector for reflecting the light beam being located on the same side of the base. The third surface is provided with a plurality of third grooves spaced apart along a fifth direction, wherein the fifth direction is the extension direction of the second connecting beam. The fourth surface is provided with a plurality of fourth grooves spaced apart along the fifth direction.
[0015] Optionally, the length of the first connecting beam in the third direction is a first length L1, and the length of the first torsion axis in the second direction is a second length L2. The ratio of the first length L1 to the second length L2 satisfies: 1.2 ≤ L1 / L2 ≤ 1.5. The third direction is the extension direction of the first connecting beam.
[0016] Based on the above structure, the galvanometer provided in the present application is provided with the first connecting beam connected to the first main body, and one end of the first torsion shaft is connected to the first connecting beam, and the other end is connected to the reflector module, so that the circumferential stress on the first torsion shaft is distributed to the first connecting beam. The first connecting beam is deformed under the force to alleviate the stress concentration phenomenon on the first torsion shaft, thereby reducing the fatigue fracture phenomenon of the first torsion shaft.
[0017] As for the aforementioned laser radar, the laser radar includes a housing, a transmitting module, a receiving module, and the aforementioned galvanometer. The transmitting module is housed in the housing and is used to transmit detection light to detect target objects. The receiving module is housed in the housing and is used to receive echo light formed by the detection light reflected by the target object. The galvanometer is used to receive the detection light and deflect it so that the detection light is emitted outside the laser radar, and to receive the echo light so that the echo light is emitted toward the receiving module.
[0018] Based on the above structure, since the above galvanometer can alleviate the stress concentration phenomenon on the first torsion axis, thereby reducing the fatigue fracture phenomenon of the first torsion axis, the laser radar provided in this application can also solve the above technical problems. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.
[0020] Figure 1 is a schematic diagram of a galvanometer provided in one embodiment of the present application;
[0021] Figure 2 This application provides Figure 1 A magnified view of part A;
[0022] Figure 3 This application provides Figure 1 B-side cross-sectional view;
[0023] Figure 4 is a schematic diagram of a galvanometer provided in another embodiment of the present application;
[0024] Figure 5 This application provides Figure 4 C-plane cross-sectional view;
[0025] Figure 6 This is a force diagram of the control group 1 provided in this application;
[0026] Figure 7 This is another force diagram of the control group 1 provided in this application;
[0027] Figure 8 This is a force diagram of the control group 2 provided in this application;
[0028] Figure 9 This is another force diagram of the control group 2 provided in this application;
[0029] Figure 10 This is a force diagram of the control group 3 provided in this application;
[0030] Figure 11 This is another force diagram of the control group 3 provided in this application;
[0031] Figure 12 This is a force diagram of Example 1 provided in this application;
[0032] Figure 13 is another force diagram of Example 1 provided in this application;
[0033] Figure 14 This is a force diagram of Example 2 provided in this application;
[0034] Figure 15 This is another force diagram of Example 2 provided in this application.
[0035] The reference numerals are as follows:
[0036] Galvanometer 1000 Fourth slot 2112 base 100 Second main body 212 First main body 110 Second connecting beam 213 First through groove 111 The third surface 2131 First slot 1111 The third groove 2131a Second slot 1112 Fourth surface 2132 First connecting beam 120 Fourth groove 2132a First surface 121 reflector 220 First groove 1211 Second torsion axis 230 Second surface 122 First torsion axis 300 Second groove 1221 First direction F1 Mirror module 200 Second direction F2 Internal frame 210 The third direction F3 Second through groove 211 Fourth Direction F4 Third slot 2111 Fifth Direction F5 DETAILED DESCRIPTION
[0037] In order to facilitate understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that when an element is described as "fixed to" another element, it can be directly on the other element, or there can be one or more centered elements therebetween. When an element is described as "connected to" another element, it can be directly connected to the other element, or there can be one or more centered elements therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this specification are for illustrative purposes only.
[0038] Unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as those commonly understood by those skilled in the art to which this application belongs. The terms used in this specification and in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" as used in this specification includes any and all combinations of one or more of the relevant listed items.
[0039] In related art, a galvanometer consists of a base, a reflector module, and a torsion shaft. The torsion shaft is connected to both sides of the reflector module and is connected to the base, allowing the reflector module to swing relative to the base around the axis of the torsion shaft. When the reflector module swings rapidly or at a large angle, the torsion shaft is subjected to significant stress, making it susceptible to fatigue fracture.
[0040] Based on this, this application provides a galvanometer 1000, please refer to Figure 1 and Figure 2 , which respectively show a schematic diagram of the galvanometer 1000 provided in one embodiment of the present application and a schematic diagram of the galvanometer 1000 provided in the present application Figure 1 In the enlarged view of section A, the galvanometer 1000 includes a base 100, a reflector module 200, and two first torsion shafts 300. The base 100 includes a first main body 110 and a first connecting beam 120. The first main body 110 is provided with a first through-slot 111 extending along a first direction F1 as shown. The first connecting beam 120 is disposed in the first through-slot 111. The first connecting beam 120 is connected to the first main body 110 at both ends, dividing the first through-slot 111 into a first slot 1111 and a second slot 1112 arranged along a second direction F2. The second direction F2 is perpendicular to the first direction F1. The reflector module 200 is disposed in the first slot 1111 for reflecting a light beam. The two first torsion shafts 300 are disposed on either side of the reflector module 200 along the second direction F2. One end of the first torsion shaft 300 is connected to the reflector module 200, and the other end extends along the second direction F2 to connect to the base 100. The first torsion shaft 300 located between the reflector module 200 and the first connecting beam 120 is connected to the first connecting beam 120 .
[0041] The specific structures of the base 100 , the reflector module 200 and the first torsion shaft 300 will be described in detail below with reference to the accompanying drawings.
[0042] For the base 100 mentioned above, see Figure 1 and Figure 2 The first main body 110 is a thin sheet-like structure that serves as the base structure for the rest of the galvanometer 1000. It defines a first through-slot 111 extending along a first direction F1 as shown. A first connecting beam 120 is disposed within the first through-slot 111, dividing the first through-slot 111 into a first slot 1111 and a second slot 1112. The first slot 1111 and the second slot 1112 are arranged along a second direction Y and are located on either side of the first connecting beam 120.
[0043] For the above-mentioned reflector module 200, please continue to refer to Figure 1 The reflector module 200 is disposed in the first groove 1111 and is a structure in the galvanometer 1000 for emitting the probe light and the echo light. The emitting mirror module 200 is a thin sheet-like structure, with a reflective material layer provided on one side thereof, in whole or in part, to reflect the probe light and the echo light. It is worth mentioning that the inner contour of the first groove 1111 can be roughly similar to the outer contour of the reflector module 200, so that the first groove 1111 is arranged in an annular shape in the reflector module 200, thereby increasing the area of the reflector module 200 and the area of the galvanometer 1000 that can reflect the light beam.
[0044] For the first torsion axis 300, please continue to refer to Figure 1The first torsion axis 300 is also located in the first groove 1111 and is a key element that enables the reflector module 200 to swing. The first torsion axis 300 extends along the second direction F2, with one end connected to the edge of the reflector module 200 and the other end extending away from the reflector module 200 along the second direction F2 to connect to the base 100. The two first torsion axes 300 are located on either side of the reflector module 200 along the second direction F2 and are arranged collinearly. Because the first torsion axis 300 is an elongated element, it can be twisted or reset around its own axis, thereby enabling the reflector module 200 to swing around the first torsion axis 300 as the rotation axis. At least one first torsion axis 300 is located between the reflector module 200 and the first connecting beam 120. The first torsion axis 300 located between the reflector module 200 and the first connecting beam 120 has one end connected to the reflector module 200 and the other end connected to the first connecting beam 120.
[0045] The provision of the first connecting beam 120 ensures that the first torsion axis 300 is not directly connected to the larger, entirely solid first main body 110. Instead, the first connecting beam 120 is suspended in the first through-slot 111 of the first main body 110, and its rigidity is lower than that of the first main body 110. At least a portion of the stress borne by the first torsion axis 300 is transferred to and borne by the first connecting beam 120. In other words, when the reflector module 200 swings rapidly or at a large angle, the galvanometer 1000 can share the stress borne by the first torsion axis 300 and the first connecting beam 120, thereby reducing the risk of fatigue fracture of the first torsion axis 300. By providing the first connecting beam 120, the force exerted on the first torsion axis 300 is transferred along the first connecting beam 120 to the first main body 110. Furthermore, the deformation of the first connecting beam 120 itself can buffer the force exerted on the first torsion axis 300, thereby improving the risk of fatigue fracture of the torsion axis in the related art, where the torsion axis is subjected to high stress.
[0046] In some embodiments of this application, please refer to Figure 1The base 100 includes two first connecting beams 120, which divide the first through-slot 111 into a first slot 1111 and two second slots 1112. Along the second direction F2, the two second slots 1112 are respectively located on both sides of the first slot 1111. Correspondingly, each first torsion axis 300 is respectively connected to a first connecting beam 120. In this way, the force applied to each first torsion axis 300 can be transmitted to the first connecting beam 120 on the corresponding side, thereby reducing the stress applied to the two first torsion axes 300 and thereby reducing the risk of fatigue fracture of the two first torsion axes 300. Optionally, the two first torsion axes 300 and the two first connecting beams 120 are symmetrically arranged on both sides of the reflector module 200, so that the stress applied can be evenly distributed on both sides of the reflector module 200 when the force is divided, thereby reducing the phenomenon of excessive force on one side of the first torsion axis 300, which may cause fatigue fracture. More specifically, each first torsion shaft 300 is connected to the middle portion of the first connecting beam 120 on the corresponding side, so that the load on the first connecting beam 120 is regularly distributed, thereby reducing stress concentration on the first connecting beam 120 .
[0047] Considering that the first connecting beam 120 is only suspended relative to the first main body 110, the first connecting beam 120 still has a relatively large rigidity, and its effect on relieving the stress on the first torsion shaft 300 is limited. The present application further improves the structure of the first connecting beam 120 to further enhance the above effect. Figure 3 , which shows that the application provides Figure 1In the cross-sectional view of side B of FIG, and in conjunction with other figures, the first connecting beam 120 has a first surface 121 and a second surface 122 arranged opposite each other along the first direction F1. The first surface 121 is located on the same side of the base 100 as the surface of the reflector module 200 for reflecting light beams. The first surface 121 is provided with a plurality of first grooves 1211 spaced apart along a third direction F3. The third direction F3 is the direction in which the first connecting beam 120 extends. In this embodiment, the third direction F3 is perpendicular to the first direction F1 and the second direction F2. Of course, in other embodiments, the third direction F3 may also have an angle other than 90 degrees with the second direction F2. It should be noted that, in this application, the phrase "the first surface 121 and the surface of the reflector module 200 for reflecting light beams are located on the same side of the base 100" means that when the galvanometer 1000 is in a non-operating state, the surface of the reflector module 200 for reflecting light beams is located on the same side of the base 100 as the first surface 121. The present application further increases the deformation capacity of the first connecting beam 120 by providing a first groove 1211 on the first surface 121, thereby improving the load-bearing capacity of the first connecting beam 120. Since the middle portion of the first connecting beam 120 is connected to the first torsion shaft 300, the middle portion of the first connecting beam 120 is not provided with the first groove 1211. This improves the connection strength between the first connecting beam 120 and the first torsion shaft 300 and prevents fatigue fracture at the connection between the first connecting beam 120 and the first torsion shaft 300. It should be understood that even though this embodiment uses the first groove 1211 provided on the first surface 121 as an example, the present application is not limited thereto. In other embodiments of the present application, the first groove 1211 may be provided on the second surface 122 instead of the first surface 121.
[0048] To further enhance the load-bearing capacity of the first connecting beam 120, in this embodiment, the second surface 122 of the first connecting beam 120 is provided with a plurality of second grooves 1221 spaced apart along the third direction F3. The addition of the second grooves 1221 further enhances the deformability of the first connecting beam 120, thereby further reducing the risk of fatigue fracture of the first torsion shaft 300 due to excessive stress.
[0049] Optionally, the notch width of the first groove 1211 and the second groove 1221 is between 0.05 mm and 0.1 mm, where the notch width refers to the dimension of the notch in the third direction F3. The depth of the first groove 1211 is less than the depth of the second groove 1221, and the depth of the first groove 1211 is between 0.01 mm and 0.02 mm, for example, the depth of the first groove 1211 can be 0.015 mm. The depth of the second groove 1221 is between 0.01 mm and 0.08 mm, for example, the depth of the second groove 1221 can be 0.05 mm.
[0050] In some embodiments, the projections of the first grooves 1211 and the second grooves 1221 along the first direction F1 are arranged alternately; for example, the projection of a first groove 1211 along the first direction F1 is completely offset from the projection of an adjacent second groove 1221 along the first direction F1. This arrangement is intended to ensure that both sides of the first connecting beam 120 are grooved to improve deformation capacity while preventing excessive material removal from the same portion of the first connecting beam 120, which could lead to fracture due to insufficient strength. In some embodiments, along the first direction F1, the sum of the depths of the first groove 1211 and the second groove 1221 is less than the thickness of the first connecting beam 120. This ensures that a layer of material remains between the first groove 1211 and the second groove 1221, ensuring the reliability of the first connecting beam 120's inherent strength.
[0051] The following further describes the length ratio between the first connecting beam 120 and the first torsion axis 300. For ease of explanation, the length of the first connecting beam 120 in the third direction F3 is defined as a first length L1, and the length of the first torsion axis 300 in the second direction F2 is defined as a second length L2. The ratio of L1 to L2 satisfies the following: 1.2 ≤ L1 / L2 ≤ 1.5. This application provides the following tests and data to demonstrate this relationship:
[0052] A control group 1 was set: the first connecting beam 120 was not provided, and only the first torsion axis 300 was provided, that is, L1 / L2 = 0.
[0053] A control group 2 is set: the length ratio of the first connecting beam 120 to the first torsion axis 300 is set to satisfy: L1 / L2 = 1.
[0054] A control group 3 is set: the length ratio of the first connecting beam 120 to the first torsion axis 300 is set to satisfy: L1 / L2 = 2.
[0055] Setting Example 1: The length ratio of the first connecting beam 120 and the first torsion axis 300 is set to satisfy: L1 / L2=1.2.
[0056] Setting Example 2: The length ratio of the first connecting beam 120 and the first torsion axis 300 is set to satisfy: L1 / L2=1.5.
[0057] The measured data are shown in Table 1 below:
[0058]
[0059] The stress distribution of the first torsion axis and the first connecting beam in each control group and embodiment can be referred to Figures 6 to 15 :
[0060] For control group 1, the stress distribution on both sides of the first torsion shaft 300 and the surface stress of the first connecting beam 120 can be referred to Figure 6 , the maximum stress distribution of the first torsion axis can be referred to Figure 7 .
[0061] For control group 2, the stress distribution on both sides of the first torsion shaft 300 and the surface stress of the first connecting beam 120 can be referred to Figure 8 , the maximum stress distribution of the first torsion axis can be referred to Figure 9 .
[0062] The stress distribution on both sides of the first torsion shaft 300 and the surface stress of the first connecting beam 120 can be referred to Figure 10 , the maximum stress distribution of the first torsion axis can be referred to Figure 11 .
[0063] In Example 1, the stress distribution on both sides of the first torsion shaft 300 and the surface stress of the first connecting beam 120 can be referred to Figure 12 , the maximum stress distribution of the first torsion axis can be referred to Figure 13 .
[0064] In Example 2, the stress distribution on both sides of the first torsion shaft 300 and the surface stress of the first connecting beam 120 can refer to Figure 14 , the maximum stress distribution of the first torsion axis can be referred to Figure 15 .
[0065] In this application, "maximum stress on the first torsion axis" refers to the maximum stress value of the first torsion axis measured when the galvanometer 1000 is in normal operating condition. In this application, "maximum impact stress on both sides of the first torsion axis" refers to the maximum stress value borne by the first torsion axis when the galvanometer 1000 or the laser radar equipped with the galvanometer 1000 is subjected to external mechanical impact. In this application, "surface stress of the first connecting beam" refers to the maximum stress value of the first connecting beam 120 measured when the galvanometer 1000 or the laser radar equipped with the galvanometer 1000 is subjected to external mechanical impact. The above parameters can reflect the stress conditions of the first torsion axis 300 and the first connecting beam 120 in the current control group or embodiment. The smaller the maximum stress borne by the first torsion axis 300, the better. The smaller the stress on both sides of the first torsion axis 300, the better. However, in Control Group 3, although the stress borne by the first torsion axis 300 is the lowest, the stress borne by the first connecting beam 120 in its structure is excessive, which can easily lead to brittle fracture of the first connecting beam 120.
[0066] In summary, when the ratio of L1 to L2 satisfies: 1.2≤L1 / L2≤1.5, the first connecting beam 120 can withstand the component force of the first torsion axis 300 and effectively reduce the stress concentration phenomenon of the first torsion axis 300 .
[0067] In combination with one or more of the above embodiments, the galvanometer 1000 in this application can be a one-dimensional galvanometer or a two-dimensional galvanometer. When the galvanometer 1000 is a one-dimensional galvanometer, it can be configured according to the structure of the galvanometer 1000 described above. When the galvanometer 1000 is a two-dimensional galvanometer, the two first connecting beams 120 described above can be connected to the two opposing first torsion shafts 300.
[0068] In some embodiments of the present application, the galvanometer 1000 is a two-dimensional galvanometer. The specific structure of the galvanometer 1000 is further described in detail below in conjunction with the accompanying drawings.
[0069] In some embodiments of this application, please refer to Figure 4 and Figure 5 , which shows a schematic diagram of the galvanometer 1000 provided in another embodiment of the present application and the Figure 4 C-side cross-sectional view. The galvanometer 1000 is a two-dimensional galvanometer. The reflector module 200 includes an inner frame 210, a reflector 220 and a second torsion axis 230. The inner frame 210 is arranged between the two first torsion axes 300 and is respectively connected to the two first torsion axes 300. The inner frame 210 is provided with a second through-slot 211 that passes through along the above-mentioned first direction F1. The reflector 220 is arranged in the second through-slot 211, and the reflector 220 is used to reflect the light beam. The two second torsion axes 230 are arranged in the second through-slot 211, and along the fourth direction F4, the two second torsion axes 230 are respectively arranged on both sides of the reflector 220. One end of the second torsion axis 230 is connected to the reflector 220, and the other end extends along the fourth direction F4 to connect to the inner frame 210. The first direction F1, the second direction F2 and the fourth direction F4 are perpendicular to each other. It should be noted that the fourth direction F4 is parallel to the plane of the inner frame 210. Since the reflector module 200 in the galvanometer 1000 will swing, when the galvanometer 1000 is stationary and not deflecting, the fourth direction F4 is parallel to the third direction F3. By providing a second torsion axis 230 perpendicular to the second direction F2, the first torsion axis 300 and the second torsion axis 230 extend perpendicularly, thereby achieving a two-dimensional galvanometer 1000 capable of bidirectional swing, thereby increasing the detection field of view of the galvanometer 1000 and improving the efficiency of the lidar.
[0070] For the inner frame 210, see Figure 4 and Figure 5The inner frame 210 includes a second main body 212 and two second connecting beams 213. The second main body 212 serves as the mounting base for part of the inner frame 210 structure, thereby supporting the reflector 220. The second main body 212 is provided with a second through-slot 211. The second connecting beam 213 is provided in the second through-slot 211. The two ends of the second connecting beam 213 are respectively connected to the second main body 212. The two second connecting beams 213 divide the second through-slot 2111 into a third slot 2111 and two fourth slots 2112 arranged along the fourth direction F4. The two fourth slots 2112 are located on both sides of the third slot 2111. The reflector 220 is provided in the third slot 2111, and each second torsion shaft 230 is connected to a corresponding second connecting beam 213. Specifically, the two second torsion shafts 230 and the two second connecting beams 213 are symmetrically arranged on both sides of the reflector 220 so that the stress applied can be evenly distributed on both sides of the reflector 220 when the stress is divided, thereby reducing the phenomenon of excessive stress on the second torsion shaft 230 on one side, resulting in fatigue fracture. More specifically, each second torsion shaft 230 is connected to the middle portion of the second connecting beam 213 on the corresponding side, so that the load applied to the second connecting beam 213 is regularly distributed, thereby reducing the stress concentration on the second connecting beam 213. It can be understood that the inner contour of the third groove 2111 is roughly similar to the outer contour of the reflector 220, so that the third groove 2111 is annularly arranged on the reflector 220, thereby increasing the area of the reflector 220 and increasing the area where the galvanometer 1000 can reflect the light beam.
[0071] Considering that the second connecting beam 213 is only set to be suspended relative to the second main body 212, the second connecting beam 213 still has a relatively large rigidity, and its effect on relieving the stress on the second torsion shaft 230 is limited. The present application further improves the structure of the second connecting beam 213 to further enhance the above effect. Figure 5 , which shows that the application provides Figure 4In the C-section view of the second connecting beam 213, and in conjunction with other figures, the second connecting beam 213 has a third surface 2131 and a fourth surface 2132 arranged opposite each other along the first direction F1. The third surface 2131 is located on the same side of the base 100 as the surface of the reflector 220 that reflects the light beam. The third surface 2131 has a plurality of third grooves 2131a spaced apart along a fifth direction F5. The fifth direction F5 is the direction in which the second connecting beam 213 extends. In this embodiment, the fifth direction F5 is perpendicular to the first direction F1 and the fourth direction F4. However, in other embodiments, the fifth direction F5 may also be at an angle other than 90 degrees to the fourth direction F4. It should be noted that, in this application, the phrase "the third surface 2131 and the surface of the reflector 220 that reflects the light beam are located on the same side of the base 100" means that when the galvanometer 1000 is in the non-operating state, the surface of the reflector 220 that reflects the light beam is located on the same side of the inner frame 210 as the third surface 2131. The present application further increases the deformation capacity of the second connecting beam 213 by providing a third groove 2131a on the third surface 2131, thereby improving the load-bearing capacity of the second connecting beam 213. Because the middle portion of the second connecting beam 213 is connected to the second torsion shaft 230, the third groove 2131a is not provided in the middle portion of the second connecting beam 213. This improves the connection strength between the second connecting beam 213 and the second torsion shaft 230 and prevents fatigue fracture at the connection between the second connecting beam 213 and the second torsion shaft 230. It should be understood that although this embodiment uses the third groove 2131a provided on the third surface 2131 as an example, the present application is not limited thereto. In other embodiments of the present application, the third groove 2131a may be provided on the fourth surface 2132 instead of the third surface 2131.
[0072] To further enhance the load-bearing capacity of the second connecting beam 213, in this embodiment, a plurality of fourth grooves 2132a are provided on the fourth surface 2132 of the second connecting beam 213, spaced apart along the fifth direction F5. The addition of the fourth grooves 2132a further enhances the deformation capacity of the second connecting beam 213, thereby further reducing the risk of fatigue fracture of the second torsion shaft 230 due to excessive stress.
[0073] Optionally, the slot width of the third groove 2131a and the fourth groove 2132a is between 0.05 mm and 0.1 mm, where the slot width refers to the size of the slot in the fifth direction F5. The depth of the third groove 2131a is less than the depth of the fourth groove 2132a, and the depth of the third groove 2131a is between 0.01 mm and 0.02 mm. For example, the depth of the third groove 2131a can be 0.015 mm. The depth of the fourth groove 2132a is between 0.01 mm and 0.08 mm. For example, the depth of the fourth groove 2132a can be 0.05 mm.
[0074] In some embodiments, the projections of the third grooves 2131a and the fourth grooves 2132a along the first direction F1 are arranged alternately; for example, the projection of the third groove 2131a along the first direction F1 is completely offset from the projection of the adjacent fourth groove 2132a along the first direction F1. This arrangement is intended to ensure that both sides of the second connecting beam 213 are grooved to enhance deformation capacity while preventing excessive material removal from the same portion of the second connecting beam 213, which could lead to fracture due to insufficient strength. In some embodiments, along the first direction F1, the sum of the depths of the third grooves 2131a and the fourth grooves 2132a is less than the thickness of the second connecting beam 213. This ensures that a layer of material remains between the third and fourth grooves 2131a, 2132a, ensuring the strength of the second connecting beam 213.
[0075] Based on the above structure, the galvanometer 1000 is further described. In the embodiment of the present application, the galvanometer 1000 can be formed by integrally etching an SOI substrate. Therefore, the above technical solution provided by the present application improves the force-bearing capacity of the first torsion axis 300 and the second torsion axis 230 in the galvanometer 1000 without adding any additional process steps during the manufacturing process of the galvanometer 1000, which is convenient and efficient. The "SOI substrate" refers to a Si l icon-On-Insul ator, which is a three-layer silicon material with a surface insulating layer.
[0076] Based on the combination of one or more of the above embodiments, the present application provides a galvanometer 1000. The galvanometer 1000 is provided with two first connecting beams 120 connected to the first main body 110 at both ends, and the end of the first torsion shaft 300 facing away from the reflector module 200 is connected to the first connecting beam 120. Therefore, when the reflector module 200 swings, the first torsion shaft 300 is subjected to force and twisted, and the stress received by the first torsion shaft 300 is transferred to the first connecting beam 120 on the corresponding side. The first connecting beam 120 buffers the stress through deformation and transfers the component force to the first main body 110, thereby alleviating the stress concentration on the first torsion shaft 300 and reducing the phenomenon of fatigue fracture of the first torsion shaft 300.
[0077] Based on the same inventive concept, the present application also provides a laser radar for improving the current situation in which the torsional axis of the galvanometer in the laser radar of the related art is prone to fatigue fracture.
[0078] The present application provides a laser radar, which includes a shell, a transmitting module, a receiving module and the galvanometer 1000 in any of the above embodiments. The shell serves as a mounting base for the laser radar, and can install, fix and protect the above structure. The transmitting module is housed in the shell, and the transmitting module is used to transmit detection light to detect the target object. The receiving module is housed in the shell, and the receiving module is used to receive the echo light formed by the reflection of the detection light through the target object. The galvanometer 1000 is used to receive the detection light and deflect it so that the detection light is emitted outside the laser radar, and to receive the echo light so that the echo light is emitted to the receiving module.
[0079] The laser radar provided in the embodiment of the present application includes the above-mentioned galvanometer 1000, so it can reduce the stress on the torsion axis and reduce the risk of fatigue fracture of the torsion axis.
[0080] It should be noted that the "detection light" mentioned in this application document means the laser beam emitted by the laser radar for detecting the target object, which can be a pulse beam or a continuous wave beam; the "echo light" mentioned in this application document means the laser beam directed to the laser radar formed by the reflection of the detection light from the target object; the "target object" mentioned in this application document means the detection object of the laser radar in the surrounding environment, which includes but is not limited to: vehicles, pedestrians, buildings, animals, vegetation, ground and sky. Next, taking the laser radar as a pulsed laser radar as an example, the specific structure of the laser radar is described in detail; it can be understood that in other embodiments of the present application, the laser radar can also be a continuous wave radar or other types of radar, and this application does not limit this.
[0081] It should be noted that the preferred embodiments of the present application are given in the specification and drawings of this application. However, the present application can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments are not intended to be additional limitations on the content of this application. The purpose of providing these embodiments is to make the understanding of the disclosure of this application more thorough and comprehensive. In addition, the above-mentioned technical features can be combined with each other to form various embodiments not listed above, which are all considered to be within the scope of the description of this application; further, it is obvious to those skilled in the art that improvements or changes can be made based on the above description, and all such improvements and changes should fall within the scope of protection of the claims attached to this application.
Claims
1. A galvanometer, characterized in that: include: The base includes a first main body and a first connecting beam, wherein the first main body is provided with a first through-slot extending along a first direction, the first connecting beam is provided in the first through-slot, and both ends of the first connecting beam are respectively connected to the first main body, dividing the first through-slot into a first slot and a second slot arranged along a second direction, wherein the second direction is perpendicular to the first direction; a reflector module, disposed in the first slot, for reflecting the light beam; and Two first torsion shafts are respectively provided on both sides of the reflector module along the second direction, one end of the first torsion shaft is connected to the reflector module, and the other end extends along the second direction to be connected to the base; The first torsion axis located between the reflector module and the first connecting beam is connected to the first connecting beam.
2. The galvanometer according to claim 1, characterized in that The base includes two first connecting beams, the two first connecting beams divide the first through slot into the first slot and two second slots, and along the second direction, the two second slots are respectively located on both sides of the first slot; Each of the first torsion shafts is correspondingly connected to a first connecting beam.
3. The galvanometer according to claim 1, wherein: The first connecting beam has a first surface and a second surface disposed opposite to each other along the first direction, and the first surface and a surface of the reflector module for reflecting the light beam are located on the same side of the base; One of the first surface and the second surface is provided with a plurality of first grooves spaced apart along a third direction, wherein the third direction is an extending direction of the first connecting beam.
4. The galvanometer according to claim 3, characterized in that: The first surface is provided with the first groove; The second surface is provided with a plurality of second grooves arranged at intervals along the third direction.
5. The galvanometer according to claim 4, characterized in that: The relationship between the first groove and the second groove satisfies at least one of the following conditions: a) the projections of the first groove and the second groove along the first direction are alternately arranged, and the projection of the first groove along the first direction is completely staggered with the projection of the adjacent second groove along the first direction; b) Along the first direction, the sum of the depth of the first groove and the depth of the second groove is less than the thickness of the first connecting beam.
6. The galvanometer according to claim 1, characterized in that The galvanometer is a two-dimensional galvanometer, and the reflector module includes: an inner frame, disposed between the two first torsion shafts and connected to the two first torsion shafts respectively, the inner frame being provided with a second through slot extending along the first direction; a reflector, disposed in the second through slot, and configured to reflect the light beam; and Two second torsion axes are arranged in the second through groove, along the fourth direction, and the two second torsion axes are respectively arranged on both sides of the reflector, one end of the second torsion axis is connected to the reflector, and the other end extends along the fourth direction to be connected to the inner frame, and the first direction, the second direction and the fourth direction are perpendicular to each other.
7. The galvanometer according to claim 6, characterized in that: The inner frame includes: A second main body portion is provided with the second through slot; and two second connecting beams, the second connecting beams being disposed in the second through slot, the two ends of the second connecting beams being respectively connected to the second main body, the two second connecting beams dividing the second through slot into a third slot and two fourth slots arranged along the fourth direction, the two fourth slots being located on either side of the third slot; The reflector is disposed in the third slot, and each of the second torsion axes is correspondingly connected to a second connecting beam.
8. The galvanometer according to claim 7, characterized in that: The second connecting beam has a third surface and a fourth surface arranged opposite to each other along the first direction, and the third surface and a surface of the reflector for reflecting the light beam are located on the same side of the base; The third surface is provided with a plurality of third grooves spaced apart along a fifth direction, wherein the fifth direction is an extension direction of the second connecting beam; The fourth surface is provided with a plurality of fourth grooves spaced apart along the fifth direction.
9. The galvanometer according to claim 1, wherein: The length of the first connecting beam in the third direction is a first length L1, and the length of the first torsion axis in the second direction is a second length L2; The ratio of the first length L1 to the second length L2 satisfies: 1.2≤L1 / L2≤1.5; Wherein, the third direction is the extension direction of the first connecting beam.
10. A laser radar, characterized in that: include: case; an emitting module, housed in the housing, for emitting detection light to detect a target object; a receiving module housed in the housing and configured to receive echo light formed by reflection of the detection light from the target object; as well as The galvanometer according to any one of claims 1 to 9, wherein the galvanometer is used to receive the detection light and deflect it so that the detection light is emitted outside the laser radar, and is used to receive the echo light so that the echo light is emitted toward the receiving module.