Two-dimensional scanning micromirror

Abstract

This invention discloses a two-dimensional scanning micromirror, comprising: a second driving unit disposed at the center of a frame, with driving beams on the left and right sides of the second driving unit rotatably connected to the frame via two slow axes; a first driving unit disposed at the center of the second driving unit along the inner circumference of the second driving unit, with the upper and lower sides of the first driving unit rotatably connected to the driving beams of the second driving unit via two short axes; and a rotating mirror disposed at the center of the first driving unit, with the upper and lower sides of the rotating mirror rotatably connected to the driving beams of the first driving unit via two long axes. This invention can improve the scanning FOV in the y-direction while ensuring the reliability of the slow axis, reduce stress in high-stress alternating areas by optimizing the distribution of reinforcing ribs, improve the reliability of electrical circuits and the overall fatigue life of the micromirror, and reduce crosstalk between fast and slow axes by short axis design and reinforcing rib layout, thereby improving operational stability.

Description

Technical Field

[0001] This invention relates to the field of MEMS two-dimensional scanning micromirror technology, and in particular to a two-dimensional scanning micromirror with high reliability and high stability. Background Technology

[0002] Two-dimensional scanning micromirrors are currently being used on a large scale in 3D sensing modules, lidar and other scenarios. In the future, relying on the advantages of laser beam scanning (LBS) technology, such as small size, low power consumption and wide color gamut, they have great development potential in the field of micro-projection display.

[0003] Currently, most mainstream 2D ​​electromagnetic scanning micromirrors use a single drive unit to simultaneously drive the fast and slow axes to achieve 2D scanning. This drive unit consists of a drive beam and a multi-turn metal coil. Although it has been partially applied, it has significant shortcomings when adapted to high-requirement scenarios such as micro-projection displays. To meet the high fast axis scanning frequency required for high resolution, existing designs need to reduce the rotational inertia of the rotating mirror, which leads to limitations on the mirror diameter, increased difficulty in optical path design, and higher costs. At the same time, the FOVs of the fast and slow axes are mutually constrained, and reducing the stiffness of the slow axis to increase the FOV will sacrifice the reliability of the slow axis. When the scanning micromirror vibrates at high frequency, the electrical circuits in the region of alternating high-frequency tensile and compressive stress inside the substrate are prone to dislocation accumulation failure due to repeated compression and stretching. The failure time is earlier than the propagation of silicon-based cracks, becoming a key factor affecting the overall fatigue life. In addition, a single drive unit driving vibrations in two vertical directions is prone to vibration crosstalk, resulting in pixel overlap and image blurring. At the maximum vibration amplitude of the slow axis, edge jitter will also occur due to high-order nonlinear forces, affecting the display effect.

[0004] Different application scenarios impose different requirements on the performance parameters of 2D scanning micromirrors. In the field of LiDAR, the line count of products using 2D scanning micromirrors is usually less than 300 lines (i.e., the vertical pixel distribution is less than 300), and the refresh rate ranges from 10Hz to 20Hz. It is calculated that its pixel frequency per second is generally less than five million. However, in the field of micro-projection display, 2D scanning micromirrors used in 1080×1920 resolution optical engines need to meet the requirement of 1080 pixels in the vertical direction, and the refresh rate needs to reach 60Hz, corresponding to a pixel output of more than 100 million per second.

[0005] From the perspective of working principle, LiDAR and micro-projection optical engines share commonalities and differences. Their core process involves a laser source emitting a laser beam to a scanning micromirror, which reflects the beam and projects it onto the object's surface. Subsequent signal / imaging acquisition is then achieved through diffuse reflection from the object's surface. The difference lies in the imaging mechanism: LiDAR collects reflected light through a receiver and calculates and generates a point cloud image, while micro-projection optical engines directly transmit diffusely reflected light to the human eye to form a visual image. Despite the different imaging mechanisms, the scanning frequency of the two-dimensional scanning micromirror directly determines the vertical pixel distribution and refresh rate of both. Compared to LiDAR, which relies on machine vision, human-eye perception has more stringent requirements for pixel density and display area. This makes the requirements for key parameters such as the scanning frequency and field of view (FOV) of the two-dimensional scanning micromirror significantly higher in the micro-projection display field than for LiDAR. This parameter difference is one of the core reasons why LBS technology has not yet achieved large-scale adoption in the domestic micro-projection display field. Summary of the Invention

[0006] The purpose of this invention is to provide a two-dimensional scanning micromirror to address the aforementioned problems in the prior art, thereby solving all or one of the aforementioned problems in the prior art.

[0007] To solve the above-mentioned technical problems, the specific technical solution of the present invention is as follows:

[0008] This invention provides a two-dimensional scanning micromirror, comprising:

[0009] A frame and a movable structure connected to the frame;

[0010] The movable structure includes: a rotating mirror, a first drive unit, a second drive unit, a fast axis, a short axis, and a slow axis;

[0011] Both the first driving unit and the second driving unit are ring-shaped;

[0012] The second drive unit is located at the center of the frame, and the drive beams on the left and right sides of the second drive unit are rotatably connected to the frame through two slow shafts.

[0013] The first driving unit is located at the center of the second driving unit along the inner circumference of the second driving unit, and the upper and lower sides of the first driving unit are rotatably connected to the driving beam of the second driving unit through two short shafts.

[0014] The rotating mirror is located at the center of the first driving unit, and its upper and lower sides are rotatably connected to the driving beam of the first driving unit via two long shafts.

[0015] As an improved solution, the first drive unit and the second drive unit have the same composition structure, both including: a drive beam, a metal drive coil and a reinforcing rib;

[0016] The drive beam is ring-shaped and is the main structural component of the first drive unit or the second drive unit.

[0017] The metal driving coil is disposed on the upper surface of the corresponding driving beam, and the reinforcing rib is disposed on the lower surface of the corresponding driving beam; the metal driving coil is used to interact with the magnetic field to generate driving force; the reinforcing rib is used to suppress the deformation of the corresponding driving beam.

[0018] As an improved solution, the second drive unit has a first avoidance area and a second avoidance area that are symmetrical about the center of the rotating mirror on the drive beams on both sides of the slow axis. The first avoidance area and the second avoidance area are specific areas around the rotating mirror.

[0019] In addition to the specific area around the drive beam of the second drive unit, the reinforcing ribs of the second drive unit are arranged close to the rotating mirror along the center line of the drive beam of the second drive unit or inside the center line.

[0020] As an improved solution, the reinforcing ribs of the second drive unit are positioned near the specific surrounding area on the drive beam of the second drive unit, and are located away from the rotating mirror along or outside the center line of the second drive unit.

[0021] As an improved solution, the reinforcing ribs of the first drive unit are arranged close to the rotating mirror along or inside the center line of the drive beam of the first drive unit.

[0022] As an improved solution, the slow axis adopts a serpentine bending beam design with multiple bends from top to bottom, and the two slow axes are centrally symmetrical about the center of the rotating mirror.

[0023] As an improved solution, the length of the first beam that bends for the first time after being connected to the frame on the slow axis is not greater than the length of the bending beams on the slow axis other than the first beam.

[0024] The length of the second beam on the slow shaft, after being connected to the drive beam of the second drive unit, is not greater than the length of the other bent beams on the slow shaft besides the second beam.

[0025] As an improved solution, the length of the minor axis along the X-axis is not less than the length of the minor axis along the Y-axis.

[0026] As an improved solution, the shape of the rotating mirror includes: circular, elliptical, or polygonal.

[0027] As an improved solution, the metal drive coil is fabricated using semiconductor processes;

[0028] The metal drive coil has a multi-turn structure.

[0029] The beneficial effects of the technical solution of this invention are:

[0030] The two-dimensional scanning micromirror described in this invention can improve the FOV of the y-axis scan without sacrificing the reliability of the slow axis; by optimizing the distribution of reinforcing ribs, it reduces the stress in the high-stress alternating area, thereby improving the reliability of the electrical circuit and the overall fatigue life of the micromirror; by using a short-axis design and reinforcing rib layout, it suppresses the transmission of vibration energy, reduces crosstalk between the fast and slow axes, and improves the working stability, thus making up for the deficiencies of the prior art and having high application value. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of the front structure of the two-dimensional scanning micromirror described in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the back structure of the two-dimensional scanning micromirror described in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the transient FOV curve of a prior art two-dimensional scanning micromirror in the y-direction during a comparative experiment of the two-dimensional scanning micromirror described in this embodiment of the invention.

[0035] Figure 4 This is a schematic diagram of the transient FOV curve of the two-dimensional scanning micromirror in the y-direction during a comparative experiment as described in the embodiments of the present invention.

[0036] Figure 5 This is a schematic diagram of the principal stress curve at the connection between the slow axis and the drive beam in the first avoidance area of ​​the prior art two-dimensional scanning micromirror when a comparative experiment is conducted on the two-dimensional scanning micromirror described in the embodiment of the present invention.

[0037] Figure 6 This is a schematic diagram of the principal stress curve at the connection between the slow axis and the drive beam of the two-dimensional scanning micromirror described in the embodiment of the present invention in the first avoidance area during a comparative experiment.

[0038] Figure 7 This is a front view of the prior art two-dimensional scanning micromirror in a comparative experiment of an embodiment of the present invention;

[0039] The markings in the attached diagram are explained as follows:

[0040] 1. Frame; 2. Rotating mirror; 3. First drive unit; 4. Second drive unit; 5. Fast axis; 6. Short axis; 7. Slow axis; 8. Drive beam; 9. Metal drive coil; 10. Reinforcing rib; 11. First clearance area; 12. Second clearance area; 13. Coil; 14. Prior art slow axis; 15. Prior art fast axis. Detailed Implementation

[0041] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0042] In the description of this invention, it should be noted that the embodiments described in this invention are only some embodiments of this invention, not all embodiments; based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] The terms "first," "second," etc., used in this specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, apparatus, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0044] This embodiment provides a two-dimensional scanning micromirror, such as... Figures 1-6 As shown, it includes: a frame 1 and a movable structure connected to the frame 1;

[0045] Specifically, the movable structure is a key component for realizing the scanning function, including: rotating mirror 2, first drive unit 3, second drive unit 4, fast axis 5, short axis 6, and slow axis 7. Each component works together to complete the two-dimensional scanning action. The corresponding structure and function are detailed below:

[0046] Specifically, the first drive unit 3 and the second drive unit 4 are the core drive components, both of which are ring-shaped. The second drive unit 4 is located at the center of the frame 1, and the drive beams 8 on the left and right sides of the second drive unit 4 are rotatably connected to the frame 1 through two slow shafts 7. The first drive unit 3 is located at the center of the second drive unit 4 along the inner circumference of the ring, and the upper and lower sides of the first drive unit 3 are rotatably connected to the drive beams 8 of the second drive unit 4 through two short shafts 6. The rotating mirror 2 is located at the center of the first drive unit 3, and the upper and lower sides of the rotating mirror 2 are rotatably connected to the drive beams 8 of the first drive unit 3 through two long shafts.

[0047] Specifically, when the device starts operating, after the metal coil on the front of the drive beam 8 of the second drive unit 4 is energized with an AC frequency current, it interacts with the magnetic field to generate a time-varying Ampere force, causing the drive beam 8 to vibrate back and forth along the x-axis passing through the center of the mirror, thereby causing the rotating mirror 2 to vibrate and achieve y-axis scanning. After the metal coil on the front of the drive beam 8 of the first drive unit 3 is energized with an AC frequency current, it generates a time-varying Ampere force, causing the drive beam 8 to vibrate back and forth along the y-axis passing through the center of the mirror, thereby causing the rotating mirror 2 to vibrate and achieve x-axis scanning. After the laser is projected onto the area of ​​the rotating mirror 2, the rotating mirror 2, driven by the first drive unit 3 and the second drive unit 4, vibrates back and forth along both the x-axis and y-axis passing through the center of the mirror, achieving y-axis and x-axis scanning. The laser is reflected to complete the two-dimensional scanning. The above is the overall architecture and working principle of this device. In order to further improve the overall performance of this device, the following targeted innovative designs have been made in the structure of this device:

[0048] In a preferred embodiment, the first driving unit 3 and the second driving unit 4 have the same structure, both including a driving beam 8, a metal driving coil 9 and a reinforcing rib 10;

[0049] The metal driving coil 9 is fabricated using semiconductor technology and is located on the front (i.e., upper surface) of the driving beam 8. The metal driving coil 9 adopts a multi-turn structure and is used to generate driving force by interacting with the magnetic field.

[0050] Among them, the reinforcing rib 10 is provided on the back (i.e. the lower surface) of the drive beam 8 to suppress the deformation of the drive beam 8 and improve the structural stability and reliability;

[0051] In a preferred embodiment, in order to ensure balanced force distribution, optimize the stress state of the slow axis 7 and improve the reliability of the slow axis 7, the slow axis 7 of this device adopts a serpentine bending beam design with multiple bends from top to bottom, and the two slow axes 7 are centrally symmetrical about the center of the rotating mirror 2.

[0052] In order to further optimize the stress state of the slow shaft 7, the length of the beam that bends for the first time after the slow shaft 7 is connected to the frame 1 is not greater than the length of other bending beams, and the length of the beam that bends for the first time after the slow shaft 7 is connected to the drive beam 8 of the second drive unit 4 is not greater than the length of other bending beams.

[0053] In a preferred embodiment, the back reinforcing ribs 10 of the first driving unit 3 and the second driving unit 4 are distributed in a targeted manner:

[0054] In this context, the second drive unit 4 has a first avoidance area 11 and a second avoidance area 12 on both sides of the drive beam 8 corresponding to the slow shaft 7. This area is a specific area around the fixed position where the slow shaft 7 and the drive beam 8 are connected. In addition to the above-mentioned specific area, the reinforcing ribs 10 of the second drive unit 4 are distributed along the center line or inside the center line of the drive beam 8, that is, close to the rotating mirror 2. The reinforcing ribs 10 close to the first avoidance area 11 and the second avoidance area 12 are distributed along the center line or outside the center line of the second drive unit 4, that is, away from the rotating mirror 2, thereby adapting to the stress distribution characteristics.

[0055] Among them, the back reinforcing ribs 10 of the first drive unit 3 are distributed close to the rotating mirror 2 along the center line or the inner side of the center line of the drive beam 8. Through the design of the above-mentioned reinforcing ribs 10, the deformation of the drive beam 8 can be suppressed, the working mode stability of the slow shaft 7 can be guaranteed, and the energy transmission efficiency can be optimized.

[0056] It should be noted that the drive beam 8 vibrates back and forth due to the Ampere force of the coil. Under this force, the drive beam 8 is prone to various torsional deformations. By designing the reinforcing ribs 10, the deformation of the drive beam 8 can be effectively suppressed, ensuring the stability of the slow axis 7 working mode. Furthermore, while ensuring that the working modes of the fast axis 5 and slow axis 7 of the MEMS micromirror remain unchanged, the distance between the reinforcing ribs 10 of the second drive unit 4 and the center of the rotating mirror 2 is reduced, thereby reducing the rotational inertia of the second drive unit 4 in the vibration direction of the slow axis 7, thus increasing the FOV of the y-direction scan. Moreover, the reinforcing ribs 10 are distributed in the above-mentioned specific area to place some of the reinforcing ribs 10 in the high stress alternating area, thereby increasing the FOV of the y-direction scan while improving the overall fatigue life of the micromirror.

[0057] It should be noted that, under the premise of ensuring the suppression of deformation of the drive beam 8 of the first drive unit 3 and the unchanged overall working mode of the fast and slow axes 7, the design of the reinforcing rib 10 on the back of the drive beam 8 of the first drive unit 3 can further reduce the moment of inertia in the vibration direction of the fast axis 5, improve the energy transmission efficiency of the first drive unit 3 to the rotating mirror 2, thereby enabling the first drive unit 3 to achieve the same FOV in the ±x direction with a lower vibration amplitude; and the reduction of the vibration amplitude of the first drive unit 3 will directly reduce the vibration energy transmitted to the second drive unit 4, thereby reducing the vibration crosstalk of the first drive unit 3 to the second drive unit 4.

[0058] In a preferred embodiment, to suppress vibration energy transmission, the length of the short axis 6 along the X-axis is set to be no less than the length of the short axis 6 along the Y-axis. Figures 1-2 In the micromirror shown, the width of the minor axis 6 is not less than its length;

[0059] It should be noted that, through the design of the short axis 6, the distance between the center of the second drive unit 4 and the rotating mirror 2 can be extended while ensuring that the working modes of the fast axis 5 and the slow axis 7 of the micromirror remain unchanged. This increases the torque of the Ampere force generated between the energized coil and the magnetic field on the second drive unit 4, thereby improving the FOV of the y-direction scan. Furthermore, based on the above aspect ratio design, the vibration energy of the first drive unit 3 is suppressed at the short axis 6, further reducing the vibration energy transmitted from the first drive unit 3 to the second drive unit 4. Combining the above designs of the reinforcing rib 10 and all related axis structures, the vibration crosstalk of the MEMS scanning micromirror between the ±x and ±y directions can be reduced, improving the overall stability of the micromirror control.

[0060] In a preferred embodiment, the rotating mirror 2 is circular, elliptical, or polygonal in shape.

[0061] In a comparative experiment, finite element multiphysics simulation was used to compare the field of view (FOV) of the two-dimensional scanning micromirror of this invention and the original two-dimensional scanning micromirror under the same driving force. The simulation results are as follows: Figure 3 and Figure 4 As shown, through the above optimizations, the FOV of the y-direction scan has been improved without sacrificing the reliability of the slow axis 7.

[0062] In a comparative experiment, the reinforcing ribs 10 of the second driving unit 4 and the first driving unit 3 were optimized using finite element multiphysics simulation. Without changing the micromirror's working mode or achieving the aforementioned effect of increasing the FOV gain in the y-direction scanning, some of the reinforcing ribs 10 were placed in the high-stress alternation region (i.e., some reinforcing ribs 10 were placed around the first avoidance region 11 and the second avoidance region 12 and away from the rotating mirror 2). This effectively reduced the maximum stress of the high-frequency stress distribution on the driving beam 8 in this region, improved the electrical reliability of the electrical circuits arranged in this region, and significantly reduced the stress distributed in this region. After testing, the simulation results are as follows: Figure 5 and Figure 6 As shown, after adopting the above optimized design, the overall fatigue life of the two-dimensional scanning micromirror is significantly improved compared with the original design.

[0063] Furthermore, the computer-readable storage medium in this embodiment can be any combination of one or more readable storage media, wherein the readable storage medium includes an electrical, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof.

[0064] Unlike existing technologies, the two-dimensional scanning micromirror of this application can improve the scanning FOV in the y-axis without sacrificing the reliability of the slow axis; by optimizing the distribution of reinforcing ribs, the stress in the high-stress alternating area is reduced, thereby improving the reliability of the electrical circuit and the overall fatigue life of the micromirror; by suppressing vibration energy transmission through short-axis design and reinforcing rib layout, the crosstalk between the fast and slow axes is reduced, and the working stability is improved, thus making up for the deficiencies of existing technologies and having high application value.

[0065] It should be understood that in the various embodiments of this document, the sequence number of each process does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this document.

[0066] It should also be understood that, in the embodiments herein, the term "and / or" is merely a description of the relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following associated objects have an "or" relationship.

[0067] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this document.

[0068] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0069] In the embodiments provided herein, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the couplings or direct couplings or communication connections shown or discussed may be indirect couplings or communication connections through some interfaces, devices, or units, or they may be electrical, mechanical, or other forms of connection.

[0070] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of the embodiments described herein, depending on actual needs.

[0071] Furthermore, the functional units in the various embodiments of this document can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0072] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this paper, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this paper. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0073] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A two-dimensional scanning micromirror, characterized by, include: A frame and a movable structure connected to the frame; The movable structure includes: a rotating mirror, a first drive unit, a second drive unit, a fast axis, a short axis, and a slow axis; Both the first driving unit and the second driving unit are ring-shaped; The second drive unit is located at the center of the frame, and the drive beams on the left and right sides of the second drive unit are rotatably connected to the frame through two slow shafts. The first driving unit is located at the center of the second driving unit along the inner circumference of the second driving unit, and the upper and lower sides of the first driving unit are rotatably connected to the driving beam of the second driving unit through two short shafts. The rotating mirror is located at the center of the first driving unit, and the upper and lower sides of the rotating mirror are rotatably connected to the driving beam of the first driving unit through two long shafts. The slow axis adopts a serpentine bending beam design with multiple bends from top to bottom, and the two slow axes are centrally symmetrical about the center of the rotating mirror; The length of the first beam that bends for the first time after being connected to the frame on the slow axis is not greater than the length of the other bending beams on the slow axis excluding the first beam. The length of the second beam on the slow shaft that bends for the first time after being connected to the drive beam of the second drive unit is not greater than the length of the other bending beams on the slow shaft besides the second beam. The length of the minor axis along the X-axis is not less than the length of the minor axis along the Y-axis.

2. The two-dimensional scanning micromirror according to claim 1, characterized in that: The first drive unit and the second drive unit have the same structure, both including: a drive beam, a metal drive coil and a reinforcing rib; The drive beam is ring-shaped and is the main structural component of the first drive unit or the second drive unit. The metal driving coil is disposed on the upper surface of the corresponding driving beam, and the reinforcing rib is disposed on the lower surface of the corresponding driving beam; the metal driving coil is used to interact with the magnetic field to generate driving force; the reinforcing rib is used to suppress the deformation of the corresponding driving beam.

3. A two-dimensional scanning micromirror according to claim 2, characterized in that: The second drive unit has a first avoidance area and a second avoidance area that are symmetrical about the center of the rotating mirror on the drive beams on both sides of the slow axis. The first avoidance area and the second avoidance area are specific areas around the mirror. In addition to the specific area around the drive beam of the second drive unit, the reinforcing ribs of the second drive unit are arranged close to the rotating mirror along the center line of the drive beam of the second drive unit or inside the center line.

4. A two-dimensional scanning micromirror according to claim 2, characterized in that: The reinforcing ribs of the second drive unit are located on the drive beam near the specific surrounding area, and are positioned along or outside the center line of the second drive unit away from the rotating mirror.

5. A two-dimensional scanning micromirror according to claim 2, characterized in that: The reinforcing ribs of the first drive unit are arranged close to the rotating mirror along the center line of the drive beam of the first drive unit or inside the center line.

6. The two-dimensional scanning micromirror according to claim 1, wherein the shape of the rotating mirror comprises a circle, an ellipse or a polygon.

7. The two-dimensional scanning micromirror according to claim 2, wherein the metal driving coil is prepared by a semiconductor process; and the metal driving coil adopts a multi-turn structure. ​ ​ ​

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