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CN-121995620-A - Micro-electromechanical system micro-mirror, optical equipment and optical communication equipment

CN121995620ACN 121995620 ACN121995620 ACN 121995620ACN-121995620-A

Abstract

The embodiment of the application provides a micro-electromechanical system (MEMS) micro-mirror, optical equipment and optical communication equipment, relates to the technical field of MEMS, and aims to solve the problem that the MEMS micro-mirror has contradiction between biaxial independent driving and packaging size and device weight. The MEMS micro mirror comprises a micro mirror chip and a magnet unit, wherein the micro mirror chip comprises a reflecting mirror, a first frame, a first torsion beam, a second frame, a second torsion beam and a fixed anchor point, the reflecting mirror is arranged on the first frame, the first frame is connected with the second frame through the first torsion beam, and the second frame is connected with the fixed anchor point through the second torsion beam. The first frame and the second frame are respectively provided with a first coil and a second coil, and a hollowed-out area is arranged between the first frame and the second frame. The magnet unit is arranged at a position opposite to the hollowed-out area and comprises a first magnet and a second magnet, wherein the first magnet and the second magnet are driving magnets of a first coil and a second coil respectively. The MEMS micromirror can be applied to optical devices and optical communication devices.

Inventors

  • TU ERQI
  • ZHAO FEI
  • FANG XIAOYONG
  • ZHANG WENMING

Assignees

  • 华为技术有限公司

Dates

Publication Date
20260508
Application Date
20241106

Claims (20)

  1. 1. A microelectromechanical system micromirror, characterized in that the microelectromechanical system micromirror comprises: The micro mirror chip comprises a reflecting mirror, a first frame, a first torsion beam, a second frame, a second torsion beam and a fixed anchor point, wherein the reflecting mirror is arranged on the first frame, the second frame is sleeved on the outer side of the first frame, the first frame is connected with the second frame through the first torsion beam, the second frame is connected with the fixed anchor point through the second torsion beam, a first coil is arranged in the first frame and used for driving the first frame to rotate around the first torsion beam, a second coil is arranged in the second frame and used for driving the second frame to rotate around the second torsion beam, a hollowed-out area is formed between the first frame and the second frame, and The magnet unit is arranged at a position opposite to the hollowed-out area and comprises a first magnet and a second magnet, wherein the first magnet is a driving magnet of the first coil, and the second magnet is a driving magnet of the second coil.
  2. 2. The mems micro-mirror of claim 1, wherein the axis of the first torsion beam is a first axis and the axis of the second torsion beam is a second axis, the first axis and the second axis being perpendicular to each other; The first frame comprises two first frame parts which are positioned at two sides of the first axis, and the first frame parts are gradually convex structures in the process of approaching to the second axis along the first axis; the second frame includes two second frame portions located on both sides of the second axis and parallel to the second axis, the second frame portions being connected to the first torsion beam.
  3. 3. The mems micro-mirror of claim 2, wherein the hollowed-out area is divided into four sub-areas according to the first axis and the second axis; the MEMS micromirror comprises four magnet units which are respectively arranged at positions opposite to the four subareas.
  4. 4. The mems micro-mirror according to claim 3, wherein the magnet unit further comprises a core post having a first side surface and a second side surface on an outer peripheral surface thereof, the first side surface being opposite to the first frame portion of the sub-region edge, the first magnet being attached to the first side surface, the second side surface being opposite to the second frame portion of the sub-region edge, the second magnet being attached to the second side surface.
  5. 5. The mems micro-mirror of claim 4, wherein the first side is parallel to the opposing first coil, the first magnet is a magnetic sheet that extends against the first side, and two magnetic poles of the magnetic sheet are arranged in a direction perpendicular to the first side.
  6. 6. The mems micro-mirror of claim 4 or 5, wherein the second side is parallel to the second coil, the second magnet is a magnetic sheet extending along the second side, and two magnetic poles of the magnetic sheet are arranged in a direction perpendicular to the second side.
  7. 7. The mems micro-mirror according to any one of claims 4-6, wherein two of the magnet units on the same side of the first axis are connected in a single structure, two of the first side faces are connected in a single side face, and two of the first magnets are connected in a single structure.
  8. 8. The mems micro-mirror of any one of claims 4 to 7, further comprising a mounting substrate, the core post being disposed on the mounting substrate; The bottom end height of the first magnet in the magnet unit is a first height, the top end height of the first magnet is a second height, the bottom end height of the second magnet is a third height, and the top end height of the second magnet is a fourth height; Wherein the first height and the third height are both lower than the fifth height; The second height and the fourth height are each greater than or equal to the fifth height.
  9. 9. The mems micro-mirror of claim 8, wherein the second height and the fourth height are each greater than or equal to the fifth height and less than or equal to twice the fifth height.
  10. 10. The mems micro-mirror according to any one of claims 4-9, wherein the mems micro-mirror further comprises a mounting substrate on which the core post is disposed, the mounting substrate being provided with a mounting groove outside a bottom of the core post, the first magnet and the second magnet being mounted in the mounting groove.
  11. 11. The mems micro-mirror according to any one of claims 4-10, wherein the core stud and the mounting substrate are a unitary structure made of soft magnetic material.
  12. 12. The mems micro mirror according to any one of claims 3-11, wherein in the two magnet units located on the same side of the second axis, the poles of the two first magnets near the first coil are different, and the poles of the two second magnets near the second coil are the same; In the two magnet units located on the same side of the first axis, the magnetic poles of the two first magnets close to the first coil are the same, and the magnetic poles of the two second magnets close to the second coil are different.
  13. 13. The mems micro-mirror according to any one of claims 2-12, wherein the first frame has a shape of a diamond or square whose diagonal coincides with the first axis and the second axis, respectively, or a circle whose center coincides with an intersection point of the first axis and the second axis, or an ellipse whose major axis and minor axis coincide with the first axis and the second axis, respectively, or an ellipse whose major axis and minor axis coincide with the second axis and the first axis, respectively.
  14. 14. The mems micro-mirror of any one of claims 1 to 13, wherein the first coil is disposed around the mirror in the first frame and extends through the first torsion beam, the second frame, and the second torsion beam to the anchor point.
  15. 15. The mems micro-mirror of any one of claims 1 to 14, wherein the first frame is integrally formed with the mirror, and wherein the outer peripheral edges of the mirror are connected to the first frame.
  16. 16. The mems micro-mirror of any one of claims 1 to 15, wherein the anchor point is located inside the first frame and in the hollowed-out area.
  17. 17. The mems micro-mirror of any one of claims 1 to 15, wherein the anchor point is located outside the first frame.
  18. 18. The mems micro-mirror of claim 17, wherein the second frame comprises an indent recessed toward the first frame at the location of the second torsion beam, the indent connected to the anchor point by the second torsion beam.
  19. 19. The mems micro-mirror of any one of claims 1 to 18, wherein the first torsion beam is a straight beam, a folded beam, a curved beam, or a serpentine beam, and the second torsion beam is a straight beam, a folded beam, a curved beam, or a serpentine beam.
  20. 20. The mems micro-mirror of any one of claims 1 to 19, further comprising an angle sensor disposed at the first torsion beam and/or the second torsion beam; the angle sensor is a Hall sensor or a piezoresistive sensor.

Description

Micro-electromechanical system micro-mirror, optical equipment and optical communication equipment Technical Field The present application relates to the field of micro-electro-mechanical systems, and in particular, to a micro-electro-mechanical system micro-mirror, an optical device, and an optical communication device. Background The Micro Electro Mechanical System (MEMS) Micro mirror (MEMS Micro mirror for short) is an MEMS device manufactured by Micro Electro mechanical system (Micro-Electro-MECHANICAL SYSTEM, MEMS) technology and integrating a reflecting mirror and an MEMS driver together, and has the advantages of light weight, small volume, low cost and the like. MEMS micromirrors are widely used as important devices for optical applications in laser projection displays, bar code scanning, and self-focusing micro microscopes. MEMS micromirrors are largely classified into electrostatic driving, electromagnetic driving (which may also be called magneto-electric driving), piezoelectric driving, and electrothermal driving, according to the driving manner. MEMS micromirrors can be divided into single and dual axes according to the scanning dimension. The biaxial MEMS micro-mirror driven by electromagnetic is a MEMS micro-mirror with wider application. However, the biaxial MEMS micro mirror adopting electromagnetic driving provided in the related art has a certain contradiction between biaxial independent driving and packaging size and device weight, that is, the product capable of realizing biaxial independent driving has the problems of large packaging size and large device weight, while the product with small packaging size and small device weight cannot realize biaxial independent driving, and the problems of large coupling crosstalk, poor motion control precision and the like exist between biaxial motions which cannot be independently driven. Disclosure of Invention The application provides a micro-electromechanical system micro-mirror, optical equipment and optical communication equipment, which are used for solving the problem that the MEMS micro-mirror has contradiction between double-shaft independent driving and packaging size and device weight. In order to achieve the above purpose, the application adopts the following technical scheme: In a first aspect, a microelectromechanical system micromirror is provided that includes a micromirror chip and a magnet unit. The micro-mirror chip comprises a reflecting mirror, a first frame, a first torsion beam, a second frame, a second torsion beam and a fixed anchor point, wherein the reflecting mirror is arranged on the first frame, the second frame is sleeved on the outer side of the first frame, the first frame is connected with the second frame through the first torsion beam, and the second frame is connected with the fixed anchor point through the second torsion beam. The first frame is provided with a first coil, the first coil is used for driving the first frame to rotate around the first torsion beam, the second frame is provided with a second coil, the second coil is used for driving the second frame to rotate around the second torsion beam, and a hollowed-out area is arranged between the first frame and the second frame. The magnet unit is arranged at a position opposite to the hollowed-out area and comprises a first magnet and a second magnet, wherein the first magnet is a driving magnet of the first coil, and the second magnet is a driving magnet of the second coil. In the micro-electromechanical system micro-mirror (MEMS micro-mirror for short), the magnetic field driving the first coil and the second coil can be separated by adopting the double-coil design of the first coil and the second coil for the micro-mirror chip and the double-magnet design of the first magnet and the second magnet for the magnet unit, so that the double-axis motion of the MEMS micro-mirror can be independently and simultaneously driven by the double coils, mechanical crosstalk between the double-axis motion can be avoided, and the motion control precision of the MEMS micro-mirror is improved. In the MEMS micro-mirror provided by the application, the magnet unit is arranged at the position opposite to the hollowed-out area in the micro-mirror chip, so that on one hand, the space inside the micro-mirror chip can be reasonably utilized, the structure of the MEMS micro-mirror is more compact, and the packaging size of the MEMS micro-mirror is reduced. On the other hand, the first magnet and the second magnet in the magnet unit can be positioned in the micro-mirror chip, the first magnet is close to the first coil, and the second magnet is close to the second coil, so that ampere force can be generated on the coil by directly utilizing the region with stronger magnetic field intensity of the magnet, the driving capability of the MEMS micro-mirror can be improved, or the volumes and the weights of the first magnet and the second magnet can be obviously reduced on the premis