Extrinsic optical fiber Fabry-Perot temperature and pressure sensor and preparation method thereof

Abstract

The present application relates to the field of sensor technology, and in particular to a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor and a preparation method thereof, comprising a multi-core optical fiber, an undoped silicon column and a doped silicon column; the multi-core optical fiber comprises a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the undoped silicon column, so as to form a silicon Fabry-Perot interference cavity between the right end face of the first fiber core and the right end face of the undoped silicon column; the right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column; the present application relates to the field of sensor technology, and in particular to a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor and a preparation method thereof, comprising a multi-core optical fiber, an undoped silicon column and a doped silicon column; the multi-core optical fiber comprises a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column; the present application relates to the field of sensor technology, and in particular to a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor and a preparation method thereof,

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor and a preparation method thereof, which can be applied to the rapid measurement of temperature and pressure dual parameters in a brick kiln. Background Art

[0002] During brick production, accurately monitoring kiln firing conditions (such as temperature and pressure) is crucial for improving brick yield and reducing energy consumption. Excessively high firing temperatures not only increase fuel consumption but can also damage the kiln, while too low temperatures can significantly reduce brick yield. Furthermore, kiln pressure significantly impacts both yield and energy consumption. Therefore, monitoring kiln temperature and pressure is an essential step in brick production.

[0003] In the related art, a temperature and pressure monitoring instrument is used to monitor the temperature and pressure in the kiln. The temperature and pressure monitoring instrument includes a temperature sensor and a pressure sensor, which are used to monitor the temperature and pressure in the kiln respectively.

[0004] However, the temperature and pressure monitoring instruments monitor the temperature and pressure in the kiln by setting temperature sensors and pressure sensors respectively. Not only is the monitoring efficiency low, but the size is also large, the structure is relatively complex, and the difficulty and cost of sensor layout are also high.

[0005] Application Contents

[0006] The present application provides a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor, which aims to solve the problems of existing temperature and pressure monitoring instruments, such as low monitoring efficiency, large size, complex structure, difficulty in sensor layout and high cost.

[0007] To achieve the above objectives, in a first aspect, the present application provides an extrinsic optical fiber Fabry-Perot temperature and pressure sensor, comprising a multi-core optical fiber, an undoped silicon column and a doped silicon column, wherein the undoped silicon column is transparent under infrared light and the doped silicon column is opaque under infrared light;

[0008] The multi-core optical fiber includes a first fiber core and a second fiber core arranged in parallel, wherein the right end face of the first fiber core contacts the left end face of the undoped silicon pillar, and the right end face of the second fiber core does not contact the left end face of the undoped silicon pillar, so as to form a silicon Fabry-Perot interferometer cavity between the right end face of the first fiber core and the right end face of the undoped silicon pillar;

[0009] The right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column.

[0010] Optional, open air Fabry-Perot interferometer cavity is used to avoid measurement errors caused by internal air pressure imbalance in the sensor under vacuum conditions.

[0011] Optionally, the undoped silicon column is cylindrical, the end face diameter of the undoped silicon column is greater than 10um, the height of the undoped silicon column is 1-1000um, and the upper and lower end faces of the undoped silicon column are both smooth surfaces and serve as the reflective surface of the sensor.

[0012] Optionally, the doped silicon column is cylindrical, the end face diameter of the doped silicon column is greater than 10um, the height of the doped silicon column is 1-1000um, and the upper and lower end faces of the doped silicon column are both smooth surfaces and serve as the reflective surface of the sensor.

[0013] Optionally, the right end face of the multi-core optical fiber is fused to the left end face of the undoped silica column or connected via high-temperature glue.

[0014] Optionally, the right end surface of the undoped silicon column and the left end surface of the doped silicon column are welded or connected by high-temperature glue.

[0015] Optionally, the silicon Fabry-Perot interferometer cavity is filled with single crystal silicon;

[0016] Optionally, the open air Fabry-Perot interferometer cavity is filled with air.

[0017] The extrinsic optical fiber Fabry-Perot temperature and pressure sensor provided by the present application can be used for the rapid measurement of the temperature and pressure dual parameters of a brick kiln, and includes a multi-core optical fiber, an undoped silicon column and a doped silicon column. The undoped silicon column is transparent under infrared light, and the doped silicon column is not transparent under infrared light; the multi-core optical fiber includes a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the undoped silicon column, so as to form a silicon Fabry-Perot interference cavity between the right end face of the first fiber core and the right end face of the undoped silicon column; the right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column; it can solve the problems that the existing temperature and pressure monitoring instruments are not only low in monitoring efficiency, but also large in size, complex in structure, and difficult and costly in sensor layout.

[0018] In a second aspect, the present application provides a method for preparing an extrinsic optical fiber Fabry-Perot temperature and pressure sensor, characterized in that the method for preparing the above-mentioned extrinsic optical fiber Fabry-Perot temperature and pressure sensor comprises:

[0019] S1. Assemble the ASE light source, spectrometer, fiber circulator, 1*2 optical switch, and multi-core optical fiber to form a sensor preparation tool;

[0020] Among them, the optical fiber circulator has port 1, port 2 and port 3 facing different directions. The ASE light source is set toward port 1, the 1*2 optical switch is set toward port 2, and the spectrometer is set toward port 3. A multi-core optical fiber is set on the side of the 1*2 optical switch away from the optical fiber circulator. The broadband light emitted by the ASE light source passes through the single-mode optical fiber, port 1, and port 2 in sequence, and selectively enters at least one core of the multi-core optical fiber.

[0021] S2. Remove the coating layer at the right end of the multi-core optical fiber to expose 2-3 cm of bare fiber, and use a fiber cleaver to cut off the right end of the multi-core optical fiber to form a flat end face;

[0022] S3. Dip the flat end face of the multi-core optical fiber into high-temperature glue. Under an optical microscope, use a fiber optic clamp to align and contact the right end face of the multi-core optical fiber with the left end face of the undoped silicon pillar.

[0023] wherein, by observing a spectrometer, ensuring that the first fiber core in the multi-core optical fiber contacts the left end face of the undoped silicon pillar, and the right end face of the second fiber core in the multi-core optical fiber does not contact the left end face of the undoped silicon pillar, so as to form a silicon Fabry-Perot interferometer cavity between the right end face of the first fiber core and the right end face of the undoped silicon pillar, the first fiber core displays an interference spectrum on the spectrometer, and the second fiber core does not display an interference spectrum on the spectrometer;

[0024] S4, curing the high temperature glue between the multi-core optical fiber and the undoped silica column;

[0025] S5. After the high-temperature adhesive is cured, the right end face of the undoped silicon pillar is dipped in the high-temperature adhesive. Under an optical microscope, a fiber optic fixture is used to align and contact the right end face of the undoped silicon pillar with the left end face of the doped silicon pillar.

[0026] The right end face of the second fiber core and the left end face of the doped silicon column are parallel to each other, so as to form an open air Fabry-Perot interferometer cavity between the right end face of the second fiber core and the left end face of the doped silicon column;

[0027] S6. Curing the high-temperature adhesive between the undoped silicon column and the doped silicon column to obtain an extrinsic optical fiber Fabry-Perot temperature and pressure sensor.

[0028] The structure of the present application and its other application objectives and beneficial effects will be more clearly understood through the description of the preferred embodiments in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A schematic diagram of the structure of a sensor preparation tool provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the structure of the sensor provided in the embodiment of the present application;

[0031] Figure 3 Interference spectrum diagram of the silicon Fabry-Perot interferometer cavity provided in an embodiment of the present application;

[0032] Figure 4 Interference spectrum diagram of the open air Fabry-Perot interferometer cavity provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present application, and should not be construed as limiting the present application. All other embodiments derived by persons of ordinary skill in the art based on the embodiments in this application without inventive effort fall within the scope of protection of this application. The embodiments of this application are described in detail below with reference to the accompanying drawings.

[0034] Reference Figures 1 to 4 As shown, the present application provides a non-intrinsic optical fiber Fabry-Perot temperature and pressure sensor, including a multi-core optical fiber, an undoped silicon column and a doped silicon column, the undoped silicon column is transparent under infrared light, and the doped silicon column is not transparent under infrared light; the multi-core optical fiber includes a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the undoped silicon column, so as to form a silicon Fabry-Perot interference cavity between the right end face of the first fiber core and the right end face of the undoped silicon column; the right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column.

[0035] Furthermore, an open air Fabry-Perot interferometer cavity is used to avoid measurement errors caused by internal air pressure imbalance in the sensor under vacuum conditions.

[0036] Furthermore, the undoped silicon column is cylindrical, the end face diameter of the undoped silicon column is greater than 10um, the height of the undoped silicon column is 1-1000um, and the upper and lower end faces of the undoped silicon column are both smooth surfaces and serve as the reflective surface of the sensor.

[0037] Furthermore, the doped silicon column is cylindrical, the end face diameter of the doped silicon column is greater than 10um, the height of the doped silicon column is 1-1000um, and the upper and lower end faces of the doped silicon column are both smooth surfaces and serve as the reflective surface of the sensor.

[0038] Furthermore, the right end face of the multi-core optical fiber is fused to the left end face of the undoped silicon column or connected via high-temperature glue.

[0039] Furthermore, the right end surface of the undoped silicon column and the left end surface of the doped silicon column are welded or connected by high-temperature glue.

[0040] Furthermore, the silicon Fabry-Perot interferometer cavity is filled with single crystal silicon; and the open air Fabry-Perot interferometer cavity is filled with air.

[0041] It should be noted that the choice of single-crystal silicon and air as the materials for the Fabry-Perot resonant cavity, due to their high thermo-optical coefficients and thermal expansion coefficients, increases the sensor's temperature sensitivity and resolution. Furthermore, the optical path difference between the silicon and air Fabry-Perot interferometer cavities varies regularly with pressure, enabling accurate pressure measurement. Furthermore, the sensor's compact structure allows for rapid temperature-pressure equilibrium, significantly improving its temperature-pressure response speed.

[0042] Sensing principle: The sensor structure in this application uses two cores in a multi-core optical fiber to form two parallel Fabry-Perot interferometer cavities, such as Figure 2 As shown in Figure 2, one is a silicon Fabry-Perot interferometer cavity and the other is an open air Fabry-Perot interferometer cavity. Since the reflectivity of the two Fabry-Perot interferometer cavities is much less than 1, their interference can be equivalent to double-beam interference, and the interference spectrum can be expressed as follows:

[0043]

[0044] Where I0(λ) is the incident light intensity, γ is the fringe visibility, λ is the wavelength of light, l=2nd is the optical path difference of the Fabry-Perot interferometer cavity, n is the refractive index of the Fabry-Perot interferometer cavity, and d is the cavity length of the Fabry-Perot interferometer cavity. is the initial phase. As the above formula shows, changes in the Fabry-Perot cavity length d and refractive index n alter the cavity's optical path difference l, shifting the interference spectrum. By tracking the interference spectrum, external parameter changes can be demodulated.

[0045] Since the refractive index of air changes with temperature and pressure, and silicon has a high thermo-optical coefficient and thermal expansion coefficient, when the external temperature or pressure changes, the cavity length and refractive index of the silicon Fabry-Perot interferometer cavity and the open air Fabry-Perot interferometer cavity in the temperature and pressure sensor structure of this application will change with temperature or pressure, causing the interference spectrum to shift. By tracking the wavelength change of the interference spectrum peak, we calibrated the temperature sensitivity of the silicon Fabry-Perot interferometer cavity in the temperature and pressure sensor of this application as T Si , the temperature sensitivity of the open air Fabry-Perot interferometer cavity is T Air The pressure sensitivity of the silicon Fabry-Perot interferometer cavity is P Si , the pressure sensitivity of the open air Fabry-Perot interferometer cavity is P Air .

[0046] Demodulation Principle: Given the known temperature and pressure sensitivities of each Fabry-Perot interferometer cavity in the temperature and pressure sensor of this application, the following formula can be used to demodulate the changes in external temperature and pressure by tracking the peak wavelength of the interference spectrum of the silicon Fabry-Perot interferometer cavity and the open air Fabry-Perot interferometer cavity in real time through a spectrometer:

[0047]

[0048] Among them, ΔT is the actual change in external temperature, ΔP is the actual change in external pressure, and Δλ Si is the peak wavelength drift of the interference spectrum of the silicon Fabry-Perot interferometer cavity, Δλ Air is the peak wavelength shift of the interference spectrum of the open air Fabry-Perot interferometer cavity.

[0049] From the above analysis, it can be seen that the temperature and pressure sensor proposed in this application can be used to monitor changes in external temperature and pressure.

[0050] During the brick production process, the temperature inside the kiln is mainly distributed between 400-1000℃, and the melting points of single-crystal silicon and optical fiber are both above 1400℃, so this sensor can be used to measure temperature and pressure inside the brick kiln.

[0051] This application uses two silicon-based microstructures and multi-core optical fibers to achieve rapid measurement of both temperature and pressure parameters. The advantages are that the sensor has a compact structure, small size, and centralized modules. It can achieve simultaneous measurement of temperature and pressure with a length of only a few hundred microns and has a fast response speed.

[0052] Specifically, the sensor has a compact structure and small size: the sensor utilizes two cores in a multi-core optical fiber and doped and undoped silicon pillars to form two parallel Fabry-Perot interferometer cavities. The maximum diameter and maximum length of the sensor are only a few hundred microns. Therefore, the sensor module is centralized and compact. The ability to simultaneously measure temperature and pressure in a small size is its greatest advantage. Fast response speed: Because the sensor in this application is small and compact, and both silicon and air have high thermal conductivity, they can quickly achieve temperature and pressure equilibrium, resulting in a fast response speed.

[0053] The extrinsic optical fiber Fabry-Perot temperature and pressure sensor provided by the present application can be used for the rapid measurement of the temperature and pressure dual parameters of a brick kiln, and includes a multi-core optical fiber, an undoped silicon column and a doped silicon column. The undoped silicon column is transparent under infrared light, and the doped silicon column is not transparent under infrared light; the multi-core optical fiber includes a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the undoped silicon column, so as to form a silicon Fabry-Perot interference cavity between the right end face of the first fiber core and the right end face of the undoped silicon column; the right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column; it can solve the problems that the existing temperature and pressure monitoring instruments are not only low in monitoring efficiency, but also large in size, complex in structure, and difficult and costly in sensor layout.

[0054] The present application also provides a method for preparing an extrinsic optical fiber Fabry-Perot temperature and pressure sensor, comprising:

[0055] S1. Assemble the ASE light source, spectrometer, fiber circulator, 1*2 optical switch, and multi-core optical fiber to form a sensor preparation tool.

[0056] Among them, the fiber circulator has port 1, port 2 and port 3 facing different directions, the ASE light source is set towards port 1, the 1*2 optical switch is set towards port 2, and the spectrometer is set towards port 3. A multi-core optical fiber is set on the side of the 1*2 optical switch away from the fiber circulator. The broadband light emitted by the ASE light source passes through the single-mode optical fiber, port 1, and port 2 in sequence, and selectively enters at least one core of the multi-core optical fiber; and reaches the sensor structure to cause Fabry-Perot interference. The interfered light returns along the original path, passes through port 2 of the fiber circulator, and enters the spectrometer from port 3 of the fiber circulator. By observing the spectrometer, the interference spectrum of the Fabry-Perot interferometer cavity can be directly seen, as shown in FIG. Figure 1 shown.

[0057] S2. Remove the coating layer at the right end of the multi-core optical fiber to expose 2-3 cm of bare fiber, and use a fiber cleaver to cut off the right end of the multi-core optical fiber to form a flat end face;

[0058] S3. Dip the flat end face of the multi-core optical fiber into high-temperature glue. Under an optical microscope, use a fiber optic clamp to align and contact the right end face of the multi-core optical fiber with the left end face of the undoped silicon pillar.

[0059] wherein, by observing a spectrometer, ensuring that the first fiber core in the multi-core optical fiber contacts the left end face of the undoped silicon pillar, and the right end face of the second fiber core in the multi-core optical fiber does not contact the left end face of the undoped silicon pillar, so as to form a silicon Fabry-Perot interferometer cavity between the right end face of the first fiber core and the right end face of the undoped silicon pillar, the first fiber core displays an interference spectrum on the spectrometer, and the second fiber core does not display an interference spectrum on the spectrometer;

[0060] S4, curing the high temperature glue between the multi-core optical fiber and the undoped silica column;

[0061] S5. After the high-temperature adhesive is cured, the right end face of the undoped silicon pillar is dipped in the high-temperature adhesive. Under an optical microscope, a fiber optic fixture is used to align and contact the right end face of the undoped silicon pillar with the left end face of the doped silicon pillar.

[0062] The right end face of the second fiber core and the left end face of the doped silicon column are parallel to each other, so as to form an open air Fabry-Perot interferometer cavity between the right end face of the second fiber core and the left end face of the doped silicon column;

[0063] S6. Curing the high-temperature adhesive between the undoped silicon column and the doped silicon column to obtain an extrinsic optical fiber Fabry-Perot temperature and pressure sensor.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. Extrinsic fiber Fabry-Perot temperature and pressure sensor, characterized in that: It includes a multi-core optical fiber, an undoped silicon column and a doped silicon column, wherein the undoped silicon column is transparent under infrared light and the doped silicon column is opaque under infrared light; The multi-core optical fiber includes a first fiber core and a second fiber core arranged in parallel, the right end face of the first fiber core contacts the left end face of the undoped silicon column, and the right end face of the second fiber core does not contact the left end face of the undoped silicon column, so as to form a silicon Fabry-Perot interferometer cavity between the right end face of the first fiber core and the right end face of the undoped silicon column; The right end face of the undoped silicon column is connected to the left end face of the doped silicon column, and the right end face of the second fiber core does not contact the left end face of the doped silicon column, so as to form an open air Fabry-Perot interference cavity between the right end face of the second fiber core and the left end face of the doped silicon column.

2. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, characterized in that: The open air Fabry-Perot interferometer cavity is used to avoid measurement errors caused by internal air pressure imbalance of the sensor under vacuum conditions.

3. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, wherein: The undoped silicon column is cylindrical, the end face diameter of the undoped silicon column is greater than 10um, the height of the undoped silicon column is 1-1000um, and the upper and lower end faces of the undoped silicon column are both smooth surfaces and serve as the reflective surface of the sensor.

4. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, characterized in that: The doped silicon column is cylindrical, the end face diameter of the doped silicon column is greater than 10 μm, the height of the doped silicon column is 1-1000 μm, and the upper and lower end faces of the doped silicon column are both smooth and serve as the reflective surface of the sensor.

5. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, wherein: The right end face of the multi-core optical fiber is fused to the left end face of the undoped silicon column or connected via high-temperature glue.

6. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, characterized in that: The right end surface of the undoped silicon column and the left end surface of the doped silicon column are welded or connected by high-temperature glue.

7. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, characterized in that: The silicon Fabry-Perot interference cavity is filled with single crystal silicon.

8. The extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to claim 1, characterized in that: The open air Fabry-Perot interference cavity is filled with air.

9. A method for preparing an extrinsic optical fiber Fabry-Perot temperature and pressure sensor, characterized in that: A method for preparing the extrinsic optical fiber Fabry-Perot temperature and pressure sensor according to any one of claims 1 to 8, comprising: S1. Assemble the ASE light source, spectrometer, fiber circulator, 1*2 optical switch, and multi-core optical fiber to form a sensor preparation tool; The optical fiber circulator has ports 1, 2, and 3 facing different directions. The ASE light source is arranged toward port 1, the 1*2 optical switch is arranged toward port 2, and the spectrometer is arranged toward port 3. The multi-core optical fiber is arranged on the side of the 1*2 optical switch away from the optical fiber circulator. The broadband light emitted by the ASE light source passes through the single-mode optical fiber, port 1, and port 2 in sequence, and then selectively enters at least one core of the multi-core optical fiber. S2. Remove the coating layer at the right end of the multi-core optical fiber to expose 2-3 cm of bare fiber, and use a fiber cleaver to cut off the right end of the multi-core optical fiber to form a flat end face; S3. Dip the flat end face of the multi-core optical fiber into high-temperature glue, and under an optical microscope, use an optical fiber clamp to align and contact the right end face of the multi-core optical fiber with the left end face of the undoped silicon pillar; wherein, by observing a spectrometer, it is ensured that the first fiber core in the multi-core optical fiber contacts the left end face of the undoped silicon pillar, and the right end face of the second fiber core in the multi-core optical fiber does not contact the left end face of the undoped silicon pillar, so as to form a silicon Fabry-Perot interferometer cavity between the right end face of the first fiber core and the right end face of the undoped silicon pillar, the first fiber core displays an interference spectrum on the spectrometer, and the second fiber core does not display an interference spectrum on the spectrometer; S4, curing the high-temperature glue between the multi-core optical fiber and the undoped silicon column; S5. After the high-temperature adhesive is cured, the right end face of the undoped silicon pillar is dipped in the high-temperature adhesive. Under an optical microscope, a fiber optic clamp is used to align and contact the right end face of the undoped silicon pillar with the left end face of the doped silicon pillar. The right end face of the second fiber core and the left end face of the doped silicon column are parallel to each other, so as to form an open air Fabry-Perot interferometer cavity between the right end face of the second fiber core and the left end face of the doped silicon column; S6. Curing the high-temperature adhesive between the undoped silicon column and the doped silicon column to obtain the extrinsic optical fiber Fabry-Perot temperature and pressure sensor.

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