Double-decoupling high-precision micro gyroscope based on cavity light power system

Abstract

The invention discloses a novel structural design of a high-precision micro-gyroscope based on a two-dimensional photonic crystal microcavity and a silicon-based ridge waveguide and a working method of the high-precision micro-gyroscope, which are mainly applied to a novel high-precision micro-gyroscope based on a cavity light force system. The gyroscope adopts a double-decoupling structural design, so that the mechanical coupling of a driving mode and a detection mode is reduced; a two-dimensional photonic crystal microcavity and an anti-collapse ridge waveguide are adopted as a detection structure, and micro-nano displacement detection is realized by utilizing the characteristics of ultrahigh sensitivity and anti-electromagnetic interference of the detection structure; a ridge waveguide structure based on a silicon-based insulator is adopted, mass block suspension is realized by reserving a 500nm silicon layer and performing bilateral 400nm etching and combining electron beam lithography (EBL) and a dry etching process, a silicon dioxide layer is protected, structural collapse is prevented, meanwhile, the manufacturing process is simplified, and compatibility with an MEMS platform is ensured. Compared with a traditional MEMS gyroscope, the gyroscope with the novel structure has remarkable advantages in the aspects of sensitivity, stability, environmental adaptability and integration, and is suitable for the fields with extremely high precision requirements, such as inertial navigation, attitude control and motion measurement.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-precision angular velocity measurement, and particularly relates to a dual-decoupled high-precision micro gyroscope based on a cavity optomechanical system. Background Art

[0002] With the development of microfabrication technology, microelectromechanical system (MEMS) gyroscopes have been widely used in fields such as aerospace, navigation and positioning, and attitude control due to their advantages of small size, light weight, low power consumption, and low cost. However, existing MEMS gyroscopes still have some limitations in performance. Especially in high-precision applications, the cross-coupling problem between the driving mode and the detection mode seriously affects the measurement accuracy and stability of the gyroscope.

[0003] The detection module of traditional silicon micro gyroscopes mainly relies on capacitive sensing technology. Its sensitivity is limited by the process error of the electrode gap, the preparation process requirements are high, and it is easily interfered by electromagnetic noise. In the traditional gyroscope structure design, the support beam structures of the driving module and the detection module are different, resulting in a mismatch of modal frequencies, which is likely to introduce cross-coupling errors during temperature changes or external vibrations, reducing the measurement accuracy; there are also some designs that improve the modal matching problem through symmetric support beams (such as U-shaped beams or folded beams), but there are still some limitations. Especially in high-precision applications, the cross-coupling problem between the driving mode and the detection mode seriously affects the measurement accuracy and stability of the gyroscope.

[0004] In recent years, optical detection schemes based on cavity optomechanical systems have received attention due to their nanoscale displacement resolution and anti-electromagnetic interference characteristics. For example, designs based on photonic crystal cavities, Zipper cavities, etc. have achieved femtometer-level sensitivity, providing new ideas for angular velocity detection. However, although breakthroughs have been made in the sensitivity of cavity optomechanical system research, it is difficult to achieve integration due to process compatibility problems. Generally speaking, existing schemes generally face two major challenges: insufficient compatibility between optomechanical sensors and MEMS processes, and it is difficult to achieve both high-precision detection and anti-environmental vibration capabilities. Summary of the Invention

[0005] The purpose of the present invention is to solve the above problems, and provide a dual-decoupled symmetric support beam design, which significantly improves the frequency matching of the driving and detection modes and reduces mechanical cross-coupling errors. At the same time, a cavity optomechanical system introducing a two-dimensional photonic crystal is utilized, and its ultra-high sensitivity and anti-electromagnetic interference characteristics are used to achieve micro-nano level displacement detection, a dual-decoupled high-precision micro gyroscope based on a cavity optomechanical system.

[0006] To solve the above technical problems, the technical solution of the present invention is: a dual-decoupled high-precision micro gyroscope based on a cavity optomechanical system, including a driving structure, a detecting structure, and a sensitive structure. The driving structure is mainly composed of several pairs of comb capacitors and a driving mass block, and has symmetric combs on both the left and right sides; the detecting structure mainly includes a cavity optomechanical system and a waveguide structure with an anti-collapse ridge. The cavity optomechanical system consists of a pair of two-dimensional photonic crystals, and the waveguide structure is composed of two symmetric ridge waveguides on the upper and lower sides; among them, the ridge waveguide is a 500-nanometer silicon dioxide layer, and 400 nanometers is etched on each side, effectively protecting the silicon dioxide layer and preventing waveguide collapse, simplifying the manufacturing process, and being better compatible with the MEMS platform; the sensitive structure includes a core mass block, which is located at the center of the gyroscope and is connected to the driving mass block and the detecting mass block respectively through suspension beams; there is a fixing post at each of the four corners of the entire gyroscope structure, fixing one end of the cantilever beam, and the other end of the cantilever beam is connected to the peripheral mass block. Among them, the driving support beam and the detecting support beam have the same structural design and are orthogonally symmetrically distributed, forming a dual-decoupled structure.

[0007] Preferably, the comb capacitors are connected to the driving mass block, and both the comb capacitors and the driving mass block are symmetrically distributed on both sides of the core mass block; by applying a DC or AC voltage excitation to the comb capacitors, push-pull driving is realized, so that the driving mass block and the core mass block perform simple harmonic vibrations along the driving direction.

[0008] Preferably, the peripheral mass blocks include a driving mass block and a detecting mass block. The sensitive mass block takes the core mass block in the middle as the core, and the peripheral mass blocks are distributed around the core mass block; a plurality of detecting support beams and driving support beams are distributed around the core mass block. All the detecting support beams are in the same axial direction, and all the driving support beams are in the same axial direction. The direction where the driving support beams are located is the driving direction, and the direction where the detecting support beams are located is the detecting direction. The driving direction and the detecting direction are arranged in a 90° cross pattern, so that the vibration modes in the driving direction and the detecting direction are completely independent in space, blocking the direct transmission path of mechanical vibration energy and realizing the characteristics of dual decoupling.

[0009] Preferably, the cantilever beam is a flexible beam. The widths of the driving support beam and the detecting support beam are both 0.5 μm. At this time, the driving mode frequency and the detecting mode frequency have good matching. Among them, the driving mode frequency ωx = 2π×40608 Hz, and the detecting mode frequency ωy = 2π×40625 Hz. The meaning of good matching is that the frequency difference < 17 Hz and the relative displacement difference is less than 1.5 nm, significantly improving the anti-environmental vibration ability of the gyroscope.

[0010] Preferably, the detecting structure includes a cavity optomechanical system, a waveguide structure with an anti-collapse ridge, and a detecting mass block. The cavity optomechanical system consists of a microcavity formed by a pair of two-dimensional photonic crystals, which are distributed on both sides of the gap between the detecting mass block and the periphery of the structure.

[0011] Preferably, the photonic crystal is composed of a number of circular holes arranged periodically in a plane, the distance between the circular holes is the same, and there is a photonic band gap between energy bands.

[0012] Preferably, the waveguide end face of the waveguide structure is placed at the gap of the photonic crystal, and the photonic crystal microcavity laterally couples the input laser through an on-chip integrated ridge waveguide, and forms an optomechanical coupling by using the dynamic change of the optical path and mechanical movement.

[0013] Preferably, the ridge waveguide is designed based on SOI wafer material, the thickness of its top silicon layer is 500 nanometers, and the lower layer is a silicon dioxide layer with a thickness of 1 to 3 microns; the top silicon layer is etched to form a ridge layer, the etching depth is 400 nanometers, and the remaining thickness is 100 nanometers, effectively protecting the silicon dioxide layer and preventing waveguide collapse; there is a long-distance transmission bus waveguide with a width of 300 nanometers running across the entire chip in the central part; one end of the bus waveguide is a tapered transition waveguide for end-face coupling with a tapered fiber lens.

[0014] The beneficial effects of the present invention are as follows: 1. For the dual-decoupled high-precision micro gyroscope based on the cavity optomechanical system provided by the present invention, through the dual-decoupled structure design, the frequency matching of the driving mode and the detection mode is significantly improved, and the mechanical cross-coupling error is reduced, thereby improving the measurement accuracy of the gyroscope.

[0015] 2. The present invention uses a cavity optomechanical system composed of a two-dimensional photonic crystal as the detection structure, which has the advantages of high quality factor and small mode field volume, etc., and realizes high-sensitivity optical detection.

[0016] 3. The ridge waveguide design in the present invention is based on an SOI substrate, retains a 500nm silicon layer and etches 400nm on both sides, which is beneficial to protecting the silicon dioxide layer and preventing collapse; only electron beam lithography (EBL) and dry etching are required to realize the suspension of the mass block, avoiding the damage of the silicon dioxide layer by wet etching, greatly simplifying the process steps, and being fully compatible with the MEMS process.

[0017] 4. The present invention reduces the mechanical coupling of the driving and detection modes through the symmetric cantilever beam design. The driving mode frequency (ωx = 2π×40608Hz) and the detection mode frequency (ωy = 2π×40625Hz) have good matching (frequency difference < 17Hz), and the relative displacement difference is less than 1.5nm, significantly improving the anti-environmental vibration ability, so that the gyroscope can still maintain stable performance in a complex environment.

[0018] 5. The present invention adopts multi-point anchoring and cavity optomechanical system design to enhance the structural stability and anti-interference ability of signal processing, and realizes high-precision angular velocity measurement.

[0019] 6. The present invention adopts the MEMS process to realize miniaturization and integration, which is convenient for installation and integration into various devices.

[0020] 7. The gyroscope of the present invention has a sensitivity of 318.7 mV / (° / s) and an angular random walk of 0.16° / h1 / 2, providing an expandable technical path for high-precision micro gyroscopes in the field of navigation and control.

[0021] 8. The present invention uses a vacuum packaging process to enhance the system's resistance to environmental noise and reduce the impact of frequency splitting on stability.

[0022] 9. Compared with traditional MEMS gyroscopes, the new structure gyroscope of the present invention has significant advantages in sensitivity, stability, environmental adaptability, and integration, and is applicable to fields with extremely high precision requirements such as inertial navigation, attitude control, and motion measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic structural diagram of the dual-decoupled high-precision micro gyroscope based on the cavity optomechanical system of the present invention;

[0024] Figure 2 is a schematic diagram of the ridge waveguide structure model of the present invention;

[0025] Figure 3 is the working principle diagram of the gyroscope of the present invention.

[0026] Description of reference numerals: 1. Driving direction; 2. Driving support beam; 3. Driving mass block; 4. Comb capacitor; 5. Detection direction; 6. Detection mass block; 7. Detection support beam; 8. Photonic crystal; 9. Waveguide structure; 10. Core mass block, 11. Fixed column. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0027] The present invention will be further described below in conjunction with the drawings and specific embodiments:

[0028] As Figures 1 to 3As shown in the figure, the double-decoupled high-precision micro gyroscope based on the cavity optomechanical system provided by the present invention includes a driving structure, a detection structure, and a sensitive structure. The driving structure is mainly composed of several pairs of comb capacitors 4 and a driving mass block 3, and has symmetric combs on both the left and right sides. The detection structure mainly includes a cavity optomechanical system and a waveguide structure 9 of an anti-collapse ridge. The cavity optomechanical system is composed of a pair of two-dimensional photonic crystals, and the waveguide structure 9 is composed of two symmetric ridge waveguides on the upper and lower sides. Among them, the ridge waveguide is a 500-nanometer silicon dioxide layer, and 400 nanometers is etched on each side, effectively protecting the silicon dioxide layer and preventing waveguide collapse, simplifying the manufacturing process, and being better compatible with the MEMS platform; the sensitive structure includes a core mass block 10, and the core mass block 10 is located at the center of the gyroscope and is connected to the driving mass block 3 and the detection mass block 6 respectively through suspension beams. There is a fixing post 11 at each of the four corners of the entire gyroscope structure, fixing one end of the cantilever beam, and the other end of the cantilever beam is connected to the peripheral mass blocks (including the driving mass block 3 and the detection mass block 6). Among them, the driving support beam 2 and the detection support beam 7 have the same structural design and are orthogonally symmetrically distributed to form a double-decoupled structure.

[0029] The comb capacitor 4 is connected to the driving mass block 3, and both the comb capacitor 4 and the driving mass block 3 are symmetrically distributed on both sides of the core mass block 10. By applying a DC or AC voltage excitation to the comb capacitor 4, push-pull driving is realized, so that the driving mass block 3 and the core mass block 10 perform simple harmonic vibrations along the driving direction. In this example, the comb capacitor 4 has a left-right symmetric structure.

[0030] The peripheral mass blocks include a driving mass block 3 and a detection mass block 6. The sensitive mass block takes the middle core mass block 10 as the core, and the peripheral mass blocks are distributed around the core mass block 10. A plurality of detection support beams 7 and driving support beams 2 are distributed around the core mass block 10. All the detection support beams 7 are in the same axial direction, and all the driving support beams 2 are in the same axial direction. The direction where the driving support beam 2 is located is the driving direction, and the direction where the detection support beam 7 is located is the detection direction. The driving direction and the detection direction are arranged in a 90° cross, so that the vibration modes in the driving direction and the detection direction are completely independent in space, blocking the direct transmission path of mechanical vibration energy and realizing the characteristic of double decoupling.

[0031] In this embodiment, the driving direction is set as the x-axis direction, Figure 1 represented by the number 1 in the figure, and the detection direction is set as the y-axis direction, Figure 1 represented by the number 5 in the figure. The cross-section of the core mass block 10 is rectangular, and the edge of the core mass block 10 is an inward concave structure, and driving support beams and detection support beams are respectively provided corresponding to the inward concave parts.

[0032] The cantilever beam is a flexible beam. The widths of the driving support beam 2 and the sensing support beam 7 are both 0.5 μm. At this time, the matching between the driving mode frequency and the sensing mode frequency is good. Among them, the driving mode frequency ωx = 2π×40608 Hz, and the sensing mode frequency ωy = 2π×40625 Hz. The good matching means that the frequency difference < 17 Hz and the relative displacement difference is less than 1.5 nm, which significantly improves the anti-environmental vibration ability of the gyroscope.

[0033] The sensing structure includes a cavity optomechanical system, a waveguide structure with anti-collapse ridges, and a sensing mass 6. The cavity optomechanical system consists of a microcavity formed by a pair of two-dimensional photonic crystals 8, which are distributed on both sides of the gap between the sensing mass 6 and the periphery of the structure.

[0034] The photonic crystal 8 is composed of a number of circular holes arranged periodically in the plane. The distances between the circular holes are the same, and there is a photonic band gap between the energy bands.

[0035] The waveguide end face of the waveguide structure 9 is placed at the gap of the photonic crystal. The photonic crystal microcavity laterally couples the input laser through an on-chip integrated ridge waveguide, and forms an optomechanical coupling by using the dynamic change of the optical path and the mechanical motion.

[0036] The ridge waveguide is designed based on SOI wafer material. The thickness of its top silicon layer is 500 nanometers, and the lower layer is a silicon dioxide layer with a thickness of 1 to 3 micrometers. Among them, the top silicon layer is etched to form a ridge layer, and the etching depth is 400 nanometers, and the remaining thickness is 100 nanometers, effectively protecting the silicon dioxide layer and preventing the waveguide from collapsing. There is a long-distance transmission bus waveguide with a width of 300 nanometers running across the entire chip in the central part. One end of the bus waveguide is a tapered transition waveguide for end-face coupling with a tapered fiber lens.

[0037] During the actual use process, such as Figure 2Shown is the specific structural diagram of a ridge waveguide based on an SOI wafer. The ridge waveguide is designed based on SOI wafer material. The thickness of the top silicon layer is 500 nm, and the bottom is a silica layer with a thickness between 1 - 3 μm. The top silicon layer is etched to form the ridge waveguide. The etching depth in the areas on both sides of the ridge waveguide reaches 400 nm, leaving a remaining thickness of 100 nm. This design can protect the silica and prevent collapse. The central part in the figure shows a long-distance transmission bus waveguide that runs through the entire chip, with a width of 300 nm. The part in close contact with the tapered fiber lens is the tapered transition waveguide, whose main function is to achieve end-face coupling. The present invention can achieve mass suspension only by electron beam lithography combined with dry etching, avoiding the damage to the silica layer by wet etching, greatly simplifying the process steps, and effectively preventing waveguide collapse. Finite element simulation and numerical calculation verification show that when using a tapered fiber lens (spot size 2 μm) to couple a 150-μm ridge waveguide, a transmission efficiency of 82% - 94% is achieved in the 1480 - 1630 nm band, with a peak value of 82.9% at the key wavelength of 1550 nm for optomechanical sensing and an end-face coupling efficiency of 46.3%, which is fully compatible with the MEMS process. Using the MEMS process, miniaturization and integration are achieved, facilitating installation and integration into various devices. During the use of the present invention, a vacuum packaging process is adopted, which can enhance the system's anti-environmental noise ability and reduce the impact of frequency splitting on stability.

[0038] See Figure 3 , the working method principle of the dual-decoupled high-precision micro gyroscope based on the cavity optomechanical system of the present invention is as follows:

[0039] When the gyroscope works, an AC voltage or a DC voltage is applied to the comb-shaped capacitor 4 of the driving module to achieve push-pull driving, driving the driving mass block 3 and the core mass block 10 to perform simple harmonic motion along the driving direction (x-axis), forming a stable driving displacement. Ideally, the motions in the driving direction and the detection direction do not affect each other.

[0040] When an external angular velocity is input along the z-axis, the core mass block will resonate along the vertical direction (y-axis) under the action of the Coriolis force, and then a displacement in the y direction will be generated. The dynamic equation of the fully decoupled microelectromechanical gyroscope in the ideal state is:

[0041]

[0042] For the convenience of analysis, let my = mc, and assume that the electrostatic force received by the driving mode is a sinusoidal wave with a constant frequency and amplitude, that is, F ex = F e sin(ω0t), where F e is the amplitude, ω0 is the driving angular frequency, m x is the mass of the driving mass block, m yTo detect the mass of the proof mass, F ex The electrostatic driving force, k x and k y are the elastic coefficients determined by the physical structure and material properties of the gyroscope in the x and y directions respectively. Substituting into the above formula (1), the equations of motion for the steady-state solutions of x(t) and y(t) can be solved:

[0043]

[0044] In the above formula, ω x is the driving mode frequency, and ω y is the detection mode frequency. It can be seen from the above formula that to maximize the detection displacement |y(t)|, ω x should be equal to ω0 to increase the amplitude of the detection displacement, and the quality factor Q x and Q y。 should be increased as much as possible. The driving mode frequency and the detection mode frequency of the present invention have good matching. Among them, the driving mode frequency ωx = 2π×40608Hz, and the detection mode frequency ωy = 2π×40625Hz. The meaning of good matching is that the frequency difference < 17Hz. Therefore, formulas (2) and (3) can be simplified as:

[0045]

[0046] Due to the y-direction displacement generated by the input of the externally applied angular velocity, it will be transmitted to the photonic crystal microcavity through the detection mass. The photonic crystal microcavity inputs the laser laterally through the on-chip integrated ridge waveguide. Specifically, the laser is input from the end face of the ridge waveguide. The ridge waveguide is composed of two symmetric upper and lower ridge waveguides. The waveguide end face is placed at the gap of the photonic crystal. The laser propagates in the waveguide and enters the photonic crystal microcavity through lateral coupling.

[0047] The photonic crystal microcavity is arranged on both sides of the gap between the detection mass 6 and the periphery of the structure. The y-direction displacement of the sensitive mass will cause corresponding changes in the gap of the photonic crystal, thereby causing dynamic changes in the optical path in the photonic crystal microcavity. The change in the optical path forms an optomechanical coupling with the mechanical motion, resulting in a change in the transmitted light power.

[0048] The change in the transmitted light power is converted into a voltage signal by a photodetector through the waveguide. The photodetector detects the change in the transmitted light power and converts it into a corresponding voltage signal, thereby calculating the magnitude of the externally applied angular velocity.

[0049] Through the combination of symmetric cantilever beam double decoupling design and high-sensitivity detection of cavity optomechanics, the gyroscope achieves precise measurement of angular velocity. By integrating the design of anti-collapse ridge waveguides, adjusting the ridge line thickness and end face width can effectively control waveguide loss while maintaining a high coupling efficiency, and also solves the problem of insufficient compatibility between optomechanical sensors and MEMS processes. The stable resonance of the driving mode and the high-Q response of the detection mode, combined with the nanoscale displacement sensitivity of the photonic crystal, enable the system to maintain excellent performance in complex environments and are suitable for high-precision inertial navigation and dynamic control scenarios.

[0050] The present invention discloses a new structural design and working method of a high-precision micro gyroscope based on a two-dimensional photonic crystal microcavity and a silicon-based ridge waveguide, mainly applied to a new type of high-precision micro gyroscope based on a cavity optomechanics system. The gyroscope adopts a double decoupling structural design to reduce the mechanical coupling between the driving and detection modes. It uses a two-dimensional photonic crystal microcavity and an anti-collapse ridge waveguide as the detection structure, and utilizes its ultra-high sensitivity and anti-electromagnetic interference characteristics to achieve micro-nano scale displacement detection. It adopts a ridge waveguide structure based on silicon-on-insulator. By retaining a 500-nm silicon layer and performing bilateral 400-nm etching, combined with electron beam lithography (EBL) and dry etching processes, the mass block is suspended, protecting the silicon dioxide layer and preventing structural collapse. At the same time, it simplifies the manufacturing process and ensures compatibility with the MEMS platform. Compared with traditional MEMS gyroscopes, the new structural gyroscope of the present invention has significant advantages in terms of sensitivity, stability, environmental adaptability, and integration, and is suitable for fields with extremely high precision requirements such as inertial navigation, attitude control, and motion measurement.

[0051] Those of ordinary skill in the art will realize that the embodiments described herein are for helping readers understand the principles of the present invention, and it should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those of ordinary skill in the art can make various other specific deformations and combinations that do not depart from the essence of the present invention based on the technical revelations disclosed in the present invention, and these deformations and combinations are still within the protection scope of the present invention.

Claims

1. A dual-decoupled high-precision micro gyroscope based on a cavity optomechanical system, characterized in that: It includes a driving structure, a detection structure and a sensitive structure. The driving structure is mainly composed of several pairs of comb capacitors (4) and a driving mass block (3), and has symmetric combs on both the left and right sides. The detection structure mainly includes a cavity optomechanical system and a waveguide structure (9) with anti-collapse ridges. The cavity optomechanical system consists of a pair of two-dimensional photonic crystals, and the waveguide structure (9) is composed of two symmetric ridge waveguides on the upper and lower sides. The ridge waveguide is a 500-nanometer silicon dioxide layer, and 400 nanometers are etched on each side, effectively protecting the silicon dioxide layer and preventing waveguide collapse, simplifying the manufacturing process and being better compatible with the MEMS platform. The sensitive structure mainly includes a core mass block (10), which is located at the center of the gyroscope and is connected to the driving mass block (3) and the detection mass block (6) respectively through suspension beams. There is a fixing post (11) at each of the four corners of the entire gyroscope structure, fixing one end of the cantilever beam, and the other end of the cantilever beam is connected to the peripheral mass block. The driving support beam (2) and the detection support beam (7) have the same structural design and are orthogonally symmetrically distributed, forming a double decoupling structure.

2. The dual-decoupled high-precision micro gyroscope for an intra-cavity optomechanical system according to claim 1, characterized in that: The comb capacitor (4) is connected to the driving mass block (3), and both the comb capacitor (4) and the driving mass block (3) are symmetrically distributed on both sides of the core mass block (10). By applying a DC or AC voltage excitation to the comb capacitor (4), push-pull driving is realized, so that the driving mass block (3) and the core mass block (10) perform simple harmonic vibrations along the driving direction.

3. The dual-decoupled high-precision micro gyroscope for an intra-cavity optomechanical system according to claim 1, wherein: The peripheral mass block includes a driving mass block (3) and a detection mass block (6). The sensitive mass block takes the middle core mass block (10) as the core, and the peripheral mass blocks are distributed around the core mass block (10). A plurality of detection support beams (7) and driving support beams (2) are distributed around the core mass block (10). All the detection support beams (7) are in the same axial direction, and all the driving support beams (2) are in the same axial direction. The direction where the driving support beam (2) is located is the driving direction, and the direction where the detection support beam (7) is located is the detection direction. The driving direction and the detection direction are arranged in a 90° cross pattern, so that the vibration modes in the driving direction and the detection direction are completely independent in space, blocking the direct transmission path of mechanical vibration energy and realizing the characteristic of double decoupling.

4. The dual-decoupled high-precision micro gyroscope for an optical cavity optomechanical system according to claim 1, characterized in that: The cantilever beam is a flexible beam. The widths of the driving support beam (2) and the detection support beam (7) are both 0.5 μm. At this time, the driving mode frequency and the detection mode frequency are well matched. The driving mode frequency ωx = 2π × 40608 Hz, and the detection mode frequency ωy = 2π × 40625 Hz. The meaning of good matching is that the frequency difference < 17 Hz and the relative displacement difference is less than 1.5 nm, significantly improving the anti-environmental vibration ability of the gyroscope.

5. The dual-decoupling high-precision micro gyroscope for an optomechanical cavity system according to claim 1, characterized in that: The detection structure includes a cavity optomechanical system, a waveguide structure (9) with anti-collapse ridges and a detection mass block (6). The cavity optomechanical system consists of a microcavity formed by a pair of two-dimensional photonic crystals (8), which are distributed on both sides of the gap between the detection mass block (6) and the structure periphery.

6. The dual-decoupled high-precision micro gyroscope for an optomechanical cavity system according to claim 1, wherein: The photonic crystal (8) is composed of a number of circular holes arranged periodically in a plane. The distances between the circular holes are the same, and there is a photonic band gap between the energy bands.

7. The dual-decoupled high-precision micro gyroscope for an optical cavity optomechanical system according to claim 1, characterized in that: The waveguide end face of the waveguide structure (9) is placed at the photonic crystal gap. The photonic crystal microcavity laterally couples and inputs the laser through the on-chip integrated ridge waveguide, and forms an optomechanical coupling by using the dynamic change of the optical path and the mechanical movement.

8. The dual-decoupled high-precision micro gyroscope for an intra-cavity optomechanical system according to claim 1, wherein: The ridge waveguide is designed based on SOI wafer material. The thickness of its top silicon layer is 500 nanometers, and the lower layer is a silicon dioxide layer with a thickness of 1 to 3 micrometers. The top silicon layer is etched to form a ridge layer, and the etching depth is 400 nanometers, with the remaining thickness of 100 nanometers, effectively protecting the silicon dioxide layer and preventing waveguide collapse. There is a long-distance transmission bus waveguide with a width of 300 nanometers running across the entire chip in the central part. One end of the bus waveguide is a tapered transition waveguide for end face coupling with a tapered fiber lens.

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