Optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip

Abstract

The invention belongs to the field of optical fiber sensors, and particularly relates to an optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip. Comprising a pressure sensitive film, a temperature sensitive film, a mass block, a first supporting plate, a second supporting plate, a third supporting plate, a fourth supporting plate, a first supporting beam and a second supporting beam. A pressure sensitive F-P cavity is formed by the first reflecting surface of the pressure sensitive film and the opposite first reflecting surface of the temperature sensitive film, a vibration sensitive F-P cavity is formed by the second side surface of the mass block and the opposite first reflecting surface of the temperature sensitive film, and a temperature sensitive F-P cavity is formed by the first reflecting surface of the temperature sensitive film and the opposite second reflecting surface of the temperature sensitive film; the temperature-sensitive F-P cavity is used for accurately sensing the environment temperature change; the vibration sensitive F-P cavity is used for detecting vibration frequency and amplitude; the pressure sensitive F-P cavity is used for measuring a pressure value; physical separation and cooperative measurement of temperature, pressure and vibration signals are realized, the problem of multi-parameter crosstalk is solved, and the stability and the service life of the chip in an extreme environment are improved.

Description

Technical Field

[0001] The present application belongs to the field of optical fiber sensors, and specifically relates to an optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip. Background Art

[0002] In areas such as the Industrial Internet of Things, aerospace engines, gas turbines, energy exploration (such as downhole oil and gas wells), and structural health monitoring, real-time, simultaneous detection of multiple physical quantities, such as temperature, pressure, and vibration, is required. Traditional single-parameter sensors require the coordination of multiple devices, resulting in complex, costly, and low-reliability systems. Furthermore, traditional electronic sensors are prone to failure in harsh environments such as nuclear power plants and aircraft engines, characterized by high temperatures, high pressures, and strong electromagnetic interference. Traditional temperature, pressure, and vibration sensors operate independently and suffer from large size, signal cross-interference, and complex installation and maintenance, making them difficult to meet integration requirements. Existing fiber-optic Fabry-Perot sensors are mostly designed for a single parameter, and multi-parameter composite measurements are prone to challenges such as decreased sensitivity, signal crosstalk, and complex demodulation algorithms. Existing composite sensor chip packaging processes are insufficient, making it difficult to achieve miniaturization while simultaneously ensuring the structural stability and long-term durability of the Fabry-Perot cavity. Summary of the Invention

[0003] In order to solve the problems of large size, signal cross-interference and difficulty in meeting integration requirements of existing composite sensors, a fiber-optic Fabry-Perot temperature-pressure-vibration composite sensitive chip is proposed. An optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip, comprising: a pressure-sensitive membrane, a temperature-sensitive membrane, a mass block, a first support plate, a second support plate, a third support plate, a fourth support plate, a first support beam, and a second support beam; The first support plate, the third support plate, the second support plate, the fourth support plate, the pressure sensitive membrane and the temperature sensitive membrane together form a square shell; The first support plate, the third support plate, the second support plate and the fourth support plate are connected end to end in sequence to form four side surfaces inside the square shell, the side surface of the first support plate and the side surface of the second support plate are arranged opposite to each other, and the side surface of the third support plate and the side surface of the fourth support plate are arranged opposite to each other; the pressure sensitive membrane and the temperature sensitive membrane are respectively fixed at two ports of the square shell, the first support beam, the second support beam and the mass block are arranged inside the square shell, one end of the first support beam is fixedly connected to the side surface of the first support plate, and the other end of the first support beam is fixedly connected to the first side surface of the mass block; one end of the second support beam is fixedly connected to the third side surface of the mass block, and the other end of the second support beam is fixedly connected to the side surface of the second support plate; the first side surface of the mass block and the third side surface of the mass block are arranged opposite to each other; The side of the pressure-sensitive membrane close to the mass block is set as the first reflection surface of the pressure-sensitive membrane, the side of the temperature-sensitive membrane close to the mass block is set as the first reflection surface of the temperature-sensitive membrane, the side of the temperature-sensitive membrane away from the mass block is set as the second reflection surface of the temperature-sensitive membrane, and the side of the mass block directly opposite the first reflection surface of the temperature-sensitive membrane is set as the second side of the mass block; the first reflection surface of the pressure-sensitive membrane and the first reflection surface of the temperature-sensitive membrane facing the first reflection surface form a pressure-sensitive FP cavity, the second side of the mass block and the first reflection surface of the temperature-sensitive membrane facing the first reflection surface form a vibration-sensitive FP cavity, and the first reflection surface of the temperature-sensitive membrane and the second reflection surface of the temperature-sensitive membrane facing the second reflection surface form a temperature-sensitive FP cavity.

[0004] Beneficial effects: The fiber-optic Fabry-Perot temperature-pressure-vibration composite sensitive chip of the present application constructs a multi-layer Fabry-Perot cavity structure, including a pressure-sensitive FP cavity (Fabry-Perot resonant cavity), a vibration-sensitive FP cavity and a temperature-sensitive FP cavity; the length of the temperature-sensitive FP cavity changes linearly with temperature, and is used to accurately sense ambient temperature changes; the vibration-sensitive FP cavity can respond to tiny displacement changes caused by external mechanical vibrations, and is used to detect vibration frequency and amplitude; the length of the pressure-sensitive FP cavity is controlled by a pressure-sensitive membrane. When external pressure acts on the pressure-sensitive membrane, the deformation of the pressure-sensitive membrane directly changes the length of the pressure-sensitive FP cavity, and the pressure-sensitive FP cavity is used to measure pressure values; the fiber-optic Fabry-Perot temperature-pressure-vibration composite sensitive chip of the present application realizes the physical separation and coordinated measurement of temperature, pressure and vibration signals, solves the problem of multi-parameter crosstalk, and improves the stability and service life of the chip in extreme environments; for the first time, the three parameters of temperature, pressure and vibration are integrated into a single chip, breaking through the limitation of the single function of traditional sensors and promoting the development of optical fiber sensing towards intelligence and high integration; BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 Schematic diagram of a fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip demodulation system according to a specific embodiment of the present invention; Figure 2 A side view of a fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to a specific embodiment of the present invention; Figure 3 This is a schematic structural diagram of the temperature-sensitive FP cavity, vibration-sensitive FP cavity, and pressure-sensitive FP cavity of the fiber Fabry-Perot temperature-pressure-vibration composite sensing chip according to a specific embodiment of the present invention; Figure 4 A top view of the structure of an optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to a specific embodiment of the present invention; In the figure, 1 is the pressure-sensitive membrane, 2 is the temperature-sensitive membrane, 3 is the mass block, 4 is the first support beam, 5 is the second support beam, 6 is the first support plate, 7 is the second support plate, 8 is the first reflection surface of the pressure-sensitive membrane, 9 is the first reflection surface of the temperature-sensitive membrane, 10 is the second reflection surface of the temperature-sensitive membrane, and 11 is the second side surface of the mass block. DETAILED DESCRIPTION

[0006] Specific implementation method 1: The following is combined with the attached embodiment of the present invention Figure 1 To the attached Figure 4 , illustrating that this embodiment clearly and completely describes the technical solutions in the embodiments of the present invention: An optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip, comprising: a pressure-sensitive membrane 1, a temperature-sensitive membrane 2, a mass block 3, a first support plate 6, a second support plate 7, a third support plate, a fourth support plate, a first support beam 4 and a second support beam 5; The first support plate 6, the third support plate, the second support plate 7, the fourth support plate, the pressure sensitive membrane 1 and the temperature sensitive membrane 2 together form a square housing; The first support plate 6, the third support plate, the second support plate 7 and the fourth support plate are connected end to end in sequence to form the four side surfaces inside the square shell, the side surface of the first support plate 6 and the side surface of the second support plate 7 are arranged opposite to each other, and the side surface of the third support plate and the side surface of the fourth support plate are arranged opposite to each other; the pressure sensitive membrane 1 and the temperature sensitive membrane 2 are respectively fixed at two ports of the square shell, the first support beam 4, the second support beam 5 and the mass block 3 are arranged inside the square shell, one end of the first support beam 4 is fixedly connected to the side surface of the first support plate 6, and the other end of the first support beam 4 is fixedly connected to the first side surface of the mass block; one end of the second support beam 5 is fixedly connected to the third side surface of the mass block, and the other end of the second support beam 5 is fixedly connected to the side surface of the second support plate; the first side surface of the mass block 3 and the third side surface of the mass block 3 are arranged opposite to each other; The side of the pressure-sensitive membrane 1 close to the mass block 3 is defined as the pressure-sensitive membrane first reflection surface 8, the side of the temperature-sensitive membrane 2 close to the mass block 3 is defined as the temperature-sensitive membrane first reflection surface 0, the side of the temperature-sensitive membrane 2 away from the mass block 3 is defined as the temperature-sensitive membrane second reflection surface 10, and the side of the mass block 3 directly opposite the temperature-sensitive membrane first reflection surface 9 is defined as the mass block second side surface 11. The pressure-sensitive membrane first reflection surface 8 and the temperature-sensitive membrane first reflection surface 9 facing the pressure-sensitive membrane form a pressure-sensitive FP cavity, the mass block second side surface 11 and the temperature-sensitive membrane first reflection surface 9 facing the pressure-sensitive membrane form a vibration-sensitive FP cavity, and the temperature-sensitive membrane first reflection surface 9 and the temperature-sensitive membrane second reflection surface 10 facing the temperature-sensitive membrane form a temperature-sensitive FP cavity.

[0007] Specifically, if Figures 2 to 3 As shown, the fiber-optic Fabry-Perot temperature-pressure-vibration composite sensitive chip of the present application constructs a multi-layer Fabry-Perot cavity structure to achieve physical separation and coordinated measurement of temperature, pressure, and vibration signals, solve the problem of multi-parameter crosstalk, and improve the stability and service life of the chip in extreme environments. For the first time, the three parameters of temperature, pressure, and vibration are integrated into a single chip, breaking through the limitation of the single function of traditional sensors and promoting the development of optical fiber sensing towards intelligence and high integration. The length of the temperature-sensitive FP cavity changes linearly with temperature, enabling precise sensing of ambient temperature changes. The distance between the second side of the mass block and the first reflective surface of the temperature-sensitive membrane is achieved through an elastic support structure, responding to minute displacement changes caused by external mechanical vibrations and used to detect vibration frequency and amplitude. The distance between the first reflective surface of the pressure-sensitive membrane and the first reflective surface of the opposite temperature-sensitive membrane is controlled by a pressure-sensitive diaphragm. When external pressure acts on the diaphragm, its deformation directly changes the length of the pressure-sensitive FP cavity, used to measure pressure. This multi-cavity integrated design enables independent detection of the three parameters of temperature, pressure, and vibration, while ensuring decoupling between them. like Figure 1 As shown, the fiber-optic Fabry-Perot temperature-pressure-vibration composite sensitive chip of the present application is used in an optical system. After the incident light beam is transmitted through the optical fiber to the temperature-sensitive FP cavity, the vibration-sensitive FP cavity, and the pressure-sensitive FP cavity, it undergoes multiple reflections in the temperature-sensitive FP cavity, the vibration-sensitive FP cavity, and the pressure-sensitive FP cavity, respectively, to form interference light fields. These interference light fields are superimposed through an optical coupler and ultimately received by a spectrum acquisition system. The spectrum acquisition system uses a high-resolution spectrometer to convert interference light signals of different wavelengths into electrical signals, and extracts the interference spectrum characteristics of each cavity through fast Fourier transform (FFT). This optical signal processing method not only improves the signal-to-noise ratio of the signal, but also achieves high-precision demodulation of the three parameters of temperature, pressure, and vibration. The analog electrical signal output by the spectral acquisition system is transmitted to the host computer via a data acquisition card. The host computer has a built-in dedicated solution algorithm that calculates the specific values ​​of temperature, pressure, and vibration based on the interference spectrum characteristics of the temperature-sensitive FP cavity, vibration-sensitive FP cavity, and pressure-sensitive FP cavity. During the solution process, multi-parameter joint demodulation technology is used, and the cross-interference between the parameters is eliminated through an iterative optimization algorithm to ensure the accuracy and reliability of the measurement results. Finally, the host computer displays the measurement data of the three parameters of temperature, pressure, and vibration in real time, and can store or remotely transmit the data as needed. Because ambient temperature fluctuations can interfere with the measurement results of the vibration- and pressure-sensitive cavities, the temperature-sensitive cavity provides temperature compensation for vibration and pressure measurements by monitoring ambient temperature changes in real time. Specifically, the output data from the temperature-sensitive cavity is used to correct temperature drift errors in the vibration- and pressure-sensitive cavities, ensuring measurement stability over a wide temperature range. This temperature compensation mechanism significantly improves the sensor's measurement accuracy across the entire temperature range, making it suitable for high-precision monitoring in complex environments. The sensitive chip can be made of materials with good light transmittance, such as silicon, borosilicate glass, sapphire, quartz, and silicon carbide.

[0008] Furthermore, the length range of the first support beam 4 and the second support beam 5 is 500 to 2mm, or the length range of the first support beam 4 and the second support beam 5 is simultaneously 100 to 300 When the length of the first support beam 4 and the second support beam 5 are both within 500 When the width of the first support beam 4 and the second support beam 5 is within the range of 20 to 50 The thickness range of the first support beam 4 and the second support beam 5 is 5 to 10 When the length range of the first support beam 4 and the second support beam 5 is simultaneously 100 to 300 When the width of the first support beam 4 and the second support beam 5 is within the range of 50 to 1000 The thickness range of the first support beam 4 and the second support beam 5 is also within 10 to 20 within the range.

[0009] Specifically, the vibration sensitive structure includes a first support beam 4, a second support beam 5 and a mass block 3; the geometric parameters of the first support beam 4 and the second support beam 5 are key factors in determining the performance of the vibration sensitive structure. The first support beam 4 and the second support beam 5 are usually manufactured using high-precision photolithography and etching technology, and their size and shape can be precisely adjusted according to the frequency range of the vibration to be measured. For low-frequency vibrations (such as seismic waves and mechanical vibrations with a frequency range of 0.1Hz to 1kHz), the design of the support beams tends to be longer in length and smaller in cross-sectional size, that is, when the lengths of the first support beam 4 and the second support beam 5 are both within 500 When the width of the first support beam 4 and the second support beam 5 is within the range of 20 to 50 The thickness range of the first support beam 4 and the second support beam 5 is 5 to 10 This design can reduce the stiffness of vibration-sensitive structures, making them more sensitive to low-frequency weak vibration signals. For high-frequency vibrations (such as ultrasound and mechanical shock, with a frequency range of 1kHz to 100kHz), the support beams are designed with shorter lengths and larger cross-sectional dimensions, that is, when the lengths of the first support beam 4 and the second support beam 5 are both within 100kHz, the support beams are designed with shorter lengths and larger cross-sectional dimensions. to 300 When the width of the first support beam 4 and the second support beam 5 is within the range of 50 to 1000 The thickness range of the first support beam 4 and the second support beam 5 is also within 10 to 20 range; this design can increase the natural frequency of the structure and ensure fast response and accurate capture of high-frequency vibrations.

[0010] Furthermore, the mass block 3 is a rectangular block made of single crystal silicon or metal.

[0011] Furthermore, the length×width×thickness of the mass block 3 ranges from 0.5 mm×0.5 mm×0.2 mm to 2 mm×2 mm×1 mm.

[0012] Specifically, the dimensions of mass block 3 (including length, width, and thickness) directly affect the inertial mass and detection sensitivity of the vibration-sensitive structure. In MEMS processes, mass block 3 is typically made of high-density materials, such as single-crystal silicon or metal. Its dimensions can be optimized based on the acceleration range and frequency characteristics of the vibration to be measured. When detecting low-frequency vibrations, the length × width × thickness of mass block 3 ranges from 1mm × 1mm × 0.5mm to 2mm × 2mm × 1mm. For low-frequency vibrations, a larger mass block is typically used to increase the inertial mass and improve the response to weak vibration signals. When detecting high-frequency vibrations, the length × width × thickness of mass block 3 ranges from 0.5mm × 0.5mm × 0.2mm to 1mm × 1mm × 0.5mm. For high-frequency vibrations, a smaller mass block is used to reduce the inertial mass and ensure a rapid response to high-frequency vibrations.

[0013] The natural frequency f of a vibration-sensitive structure can be estimated using the following formula: ;in, k is the stiffness of the supporting beam, m is the mass of the mass block; By adjusting the size of the support beam and the size of the mass, the natural frequency of the structure can be precisely controlled to match the frequency range of the vibration signal to be measured.

[0014] Where k is the stiffness of the support beam, and m is the mass of the mass block. By adjusting the dimensions of the support beam and the mass block, the natural frequency of the structure can be precisely controlled to match the frequency range of the vibration signal to be measured.

[0015] Furthermore, the distance between the first reflective surface 8 of the pressure-sensitive membrane and the first reflective surface 9 of the temperature-sensitive membrane facing it is in the range of 10 to 1000 mm; the distance between the second side surface 11 of the mass block and the first reflective surface 9 of the temperature-sensitive membrane facing it is in the range of 10 to 1000 mm; and the distance between the first reflective surface 9 of the temperature-sensitive membrane and the second reflective surface 10 of the temperature-sensitive membrane facing it is in the range of 100 to 10 mm.

[0016] Specifically, the distance between the first reflective surface 8 of the pressure-sensitive membrane and the first reflective surface 9 of the temperature-sensitive membrane facing it is the length of the pressure-sensitive FP cavity; the distance between the second side surface 11 of the mass block and the first reflective surface 9 of the temperature-sensitive membrane facing it is the vibration-sensitive FP cavity; and the distance between the first reflective surface 9 of the temperature-sensitive membrane and the second reflective surface 10 of the temperature-sensitive membrane facing it is the temperature-sensitive FP cavity. To adapt to different application scenarios and the performance requirements of the demodulator, the lengths of the temperature-sensitive FP cavity, the vibration-sensitive FP cavity, and the pressure-sensitive FP cavity are designed to be adjustable. The length of the temperature-sensitive FP cavity is usually set to hundreds of microns to several millimeters to meet the measurement requirements of different temperature ranges; the length of the pressure-sensitive FP cavity is optimized according to the pressure measurement range and diaphragm sensitivity, usually between tens of microns and hundreds of microns; the length of the vibration-sensitive FP cavity is adjusted according to the vibration frequency range and detection accuracy requirements, usually between tens of microns and hundreds of microns. This flexible design enables the sensor to adapt to a variety of application scenarios while ensuring the optimization of measurement performance.

[0017] Furthermore, the pressure sensitive membrane is a circular membrane; one fifth of the thickness of the pressure sensitive membrane is greater than the maximum deflection of the pressure sensitive membrane; The calculation formula for the maximum deflection of the pressure sensitive membrane is: ,in, is the maximum deflection of the pressure sensitive membrane, is the pressure load of the pressure sensitive membrane, is Poisson's ratio, E is the elastic modulus, R is the effective radius of the pressure sensitive membrane, h is the thickness of the pressure sensitive film.

[0018] Specifically, when the pressure sensitive membrane is subjected to an external pressure load, a small deflection will occur, which means that the maximum deformation of the pressure sensitive membrane after being subjected to a pressure load perpendicular to it must be less than one-fifth of the thickness of the membrane; for a circular diaphragm with peripheral clamps, when it is subjected to an external uniform pressure load, When the effect is applied, the deflection change equation of the circular diaphragm can be constructed: in, When the radius of the pressure sensitive membrane is r Deflection at position r =0, the pressure sensitive membrane has the maximum deflection : Thus, the relationship between the pressure magnitude and the deflection of the pressure sensitive membrane can be obtained. When the pressure sensitive membrane of the sensor is subjected to external pressure, the pressure sensitive membrane produces a slight deformation, which in turn causes the length value of the pressure sensitive FP cavity to change.

[0019] Furthermore, the temperature sensitive film 2 is a sensitive film made of sapphire, borosilicate glass or silicon.

[0020] Specifically, the thickness of the temperature-sensitive film can be adjusted according to the required temperature to be measured. The first reflective surface of the temperature-sensitive film and the second reflective surface opposite to it form a temperature-sensitive FP cavity. The distance between the first reflective surface of the temperature-sensitive film and the second reflective surface opposite to it changes linearly with temperature. Without changing the original processing technology, a Fourier transform algorithm is used to calculate the required temperature cavity thickness at different measurement temperatures using multi-cavity interference spectroscopy of the pressure-sensitive FP cavity, vibration-sensitive FP cavity, and temperature-sensitive FP cavity. Through different temperature drift experiments, a one-to-one correspondence between the zero drift of the pressure-vibration sensor and the temperature change is obtained. At the same time, by fitting the relationship between the sensitivity of the pressure-vibration parameter and temperature and combining it with the zero drift of the vibration sensor, a temperature decoupling algorithm is designed to decouple the temperature cross-sensitivity of the pressure-vibration parameter.

[0021] Furthermore, the first support plate 6 and the second support plate 7 are support plates made of metal copper.

[0022] Optical FP (Fabry-Perot cavity) MEMS (microsystem) sensors utilize micro-nanofabrication technology to construct a multi-layer Fabry-Perot cavity structure, achieving physical separation and coordinated measurement of temperature, pressure, and vibration signals, addressing the challenge of multi-parameter crosstalk. High-temperature-resistant silicon-based composite materials, combined with MEMS packaging techniques, enhance the chip's stability and service life in extreme environments. Embedded wavelength-phase hybrid demodulation technology separates multiple physical quantity signals through deep learning algorithms, improving detection accuracy and response speed. For the first time, the three parameters of temperature, pressure, and vibration are integrated into a single MEMS chip, breaking through the limitations of traditional sensors with single functions and driving the development of intelligent, highly integrated fiber optic sensing. Through the integrated innovation of fiber Fabry-Perot sensitive chips, the technical challenges of multi-parameter composite sensing are resolved, combining the advantages of high precision, interference resistance, and miniaturization.

[0023] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be employed in conjunction with other described embodiments.

Claims

1. An optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip, characterized in that: include: A pressure sensitive membrane, a temperature sensitive membrane, a mass block, a first support plate, a second support plate, a third support plate, a fourth support plate, a first support beam, and a second support beam; The first support plate, the third support plate, the second support plate, the fourth support plate, the pressure sensitive membrane and the temperature sensitive membrane together form a square shell; The first support plate, the third support plate, the second support plate and the fourth support plate are connected end to end in sequence to form four side surfaces inside the square shell, the side surface of the first support plate and the side surface of the second support plate are arranged opposite to each other, and the side surface of the third support plate and the side surface of the fourth support plate are arranged opposite to each other; the pressure sensitive membrane and the temperature sensitive membrane are respectively fixed at two ports of the square shell, the first support beam, the second support beam and the mass block are arranged inside the square shell, one end of the first support beam is fixedly connected to the side surface of the first support plate, and the other end of the first support beam is fixedly connected to the first side surface of the mass block; one end of the second support beam is fixedly connected to the third side surface of the mass block, and the other end of the second support beam is fixedly connected to the side surface of the second support plate; the first side surface of the mass block and the third side surface of the mass block are arranged opposite to each other; The side of the pressure-sensitive membrane close to the mass block is set as the first reflection surface of the pressure-sensitive membrane, the side of the temperature-sensitive membrane close to the mass block is set as the first reflection surface of the temperature-sensitive membrane, the side of the temperature-sensitive membrane away from the mass block is set as the second reflection surface of the temperature-sensitive membrane, and the side of the mass block directly opposite the first reflection surface of the temperature-sensitive membrane is set as the second side of the mass block; the first reflection surface of the pressure-sensitive membrane and the first reflection surface of the temperature-sensitive membrane facing the first reflection surface form a pressure-sensitive FP cavity, the second side of the mass block and the first reflection surface of the temperature-sensitive membrane facing the first reflection surface form a vibration-sensitive FP cavity, and the first reflection surface of the temperature-sensitive membrane and the second reflection surface of the temperature-sensitive membrane facing the second reflection surface form a temperature-sensitive FP cavity.

2. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The length range of the first support beam and the second support beam is 500mm. to 2mm, or the length range of the first support beam and the second support beam is simultaneously 100 to 300 When the lengths of the first support beam and the second support beam are both within 500 When the width of the first support beam and the second support beam is within the range of 20 to 50 The thickness range of the first support beam and the second support beam is 5 to 10 When the length range of the first support beam and the second support beam is simultaneously within 100 to 300 When the width of the first support beam and the second support beam is within the range of 50 to 1000 The thickness range of the first support beam and the second support beam is also within 10 to 20 within the range.

3. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The mass block is a rectangular block made of single crystal silicon or metal.

4. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 3, characterized in that: The length×width×thickness of the mass block ranges from 0.5 mm×0.5 mm×0.2 mm to 2 mm×2 mm×1 mm.

5. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The distance between the first reflective surface of the pressure sensitive film and the first reflective surface of the temperature sensitive film facing it is within the range of 10 to 1000 The distance between the second side of the mass block and the first reflecting surface of the temperature sensitive film is within 10 to 1000 The distance between the first reflective surface of the temperature sensitive film and the second reflective surface of the temperature sensitive film is within the range of 100 To within 10mm.

6. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The pressure sensitive membrane is a circular membrane; one fifth of the thickness of the pressure sensitive membrane is greater than the maximum deflection of the pressure sensitive membrane; The calculation formula for the maximum deflection of the pressure sensitive membrane is: ,in, is the maximum deflection of the pressure sensitive membrane, is the pressure load of the pressure sensitive membrane, is Poisson's ratio, E is the elastic modulus, R is the effective radius of the pressure sensitive membrane, and h is the thickness of the pressure sensitive membrane.

7. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The temperature sensitive film is a sensitive film made of sapphire, borosilicate glass or silicon.

8. The optical fiber Fabry-Perot temperature-pressure-vibration composite sensitive chip according to claim 1, characterized in that: The first support plate and the second support plate are support plates made of metal copper.

Images