Acoustic pressure sensor based on the fabry-perot principle and method for manufacturing same

Abstract

This invention relates to the field of acoustic wave measurement technology, and more particularly to a sound pressure sensor based on the Fabry-Perot principle and its manufacturing method, comprising: a sleeve, the sleeve including a horn-shaped cavity; an optical fiber, fixedly disposed on the sleeve and located at the end with the smaller opening of the horn-shaped cavity, the end of the optical fiber inside the horn-shaped cavity including a first reflecting surface; an array diaphragm, fixedly disposed on the sleeve and located at the end with the larger opening of the horn-shaped cavity, the end of the array diaphragm inside the horn-shaped cavity including a second reflecting plane; and a plurality of protrusions arranged in an array on the surface of the array diaphragm at the other end of the second reflecting surface. In this invention, the array diaphragm is provided with a plurality of protrusions arranged in an array on the surface of the diaphragm at the other end of the second reflecting surface. The design of these protrusions helps to increase the deflection change of the diaphragm under the action of sound waves, amplifying the influence of external sound pressure on the deflection of the center point of the compressed diaphragm, thereby enhancing the sensitivity of the sensor.

Description

Technical Field

[0001] This invention relates to the field of acoustic wave measurement technology, and in particular to an acoustic pressure sensor based on the Fabry-Perot principle and its manufacturing method. Background Technology

[0002] Depending on the application environment, fiber optic acoustic pressure sensors can be divided into two types: "fiber optic microphones" that operate in air and "fiber optic hydrophones" that operate in water or liquid. Existing Fabry-Perot principle fiber optic acoustic pressure sensors use a flat circular diaphragm as an acoustic transducer, which is fixed by a sleeve. Then, a flattened fiber optic end face is aligned with the center point of the diaphragm. The two reflecting surfaces constitute a basic Fabry-Perot interferometer. When different sound pressures are applied to the diaphragm, the deflection at the center point of the diaphragm changes differently, resulting in different interference signals. By demodulating the interference signal, the magnitude of the external sound pressure can be deduced, thus achieving the measurement of sound pressure.

[0003] In the prior art, when a flat circular diaphragm is used as an acoustic transducer, the deflection change after being subjected to sound pressure is small, resulting in low sensitivity of the sound pressure sensor.

[0004] The information disclosed in this background section is intended only to enhance the understanding of the general background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0005] This invention provides a sound pressure sensor based on the Fabry-Perot principle and its manufacturing method, thereby effectively solving the problems in the background art.

[0006] To achieve the above objectives, the technical solution adopted by this invention is: a sound pressure sensor based on the Fabry-Perot principle, comprising:

[0007] A sleeve, the sleeve comprising a funnel-shaped cavity;

[0008] An optical fiber is fixedly disposed on the sleeve and located at the end of the horn-shaped cavity with a smaller opening. The end of the optical fiber inside the horn-shaped cavity includes a first reflective surface.

[0009] An array diaphragm is fixedly disposed on the sleeve and located at the end of the larger opening of the horn-shaped cavity. The array diaphragm includes a second reflective plane at one end inside the horn-shaped cavity, and a Fabry-Perot cavity is formed between the first reflective surface and the second reflective surface.

[0010] The array diaphragm has a plurality of protrusions at the other end of the second reflective surface, and the plurality of protrusions are arranged in an array on the surface of the diaphragm.

[0011] Furthermore, the protrusions are arranged in a grid pattern.

[0012] Furthermore, the protrusions are equally spaced on any diameter of the array diaphragm surface, and along any direction perpendicular to the diameter, the number of protrusions gradually decreases from the middle to both sides.

[0013] Furthermore, the protrusion includes any one of the following structures: cube structure, cuboid structure, cylindrical structure, frustum structure, truncated cone structure, and pyramid structure.

[0014] Furthermore, the sleeve and the array diaphragm are made of quartz.

[0015] Furthermore, the diameter of the smaller end of the flared cavity opening of the sleeve is 2-3 micrometers larger than the diameter of the optical fiber.

[0016] The present invention also includes a method for manufacturing a sound pressure sensor based on the Fabry-Perot principle, comprising the following steps:

[0017] Through multi-laser integrated additive and subtractive processing technology, patterns are etched on the surface of a circular diaphragm to form an array of protrusions, thus forming an array diaphragm;

[0018] The sleeve is manufactured;

[0019] The array diaphragm is bonded and fixed at the end of the horn-shaped cavity of the sleeve with a larger opening, and the end with the protrusion is located outside the cavity during bonding.

[0020] Insert the optical fiber into the smaller end of the horn-shaped cavity of the sleeve, so that the first reflective surface of the optical fiber is directly opposite the center of the second reflective surface of the array diaphragm, and fix it so that the distance between the optical fiber and the array diaphragm is consistent.

[0021] An external spectrometer is used to obtain the optimal interference fringes, and the cavity length of the Fabry-Perot interferometer is fixed.

[0022] Furthermore, the process of etching patterns onto the surface of a circular diaphragm using a multi-laser integrated additive and subtractive manufacturing process includes the following steps:

[0023] Circular films were fabricated using carbon dioxide laser additive manufacturing technology with molten silicon dioxide as the raw material.

[0024] Picosecond lasers are used to etch protrusions arranged in a grid pattern on a film.

[0025] Furthermore, the coating layer of the optical fiber is removed before it is inserted into the sleeve.

[0026] Furthermore, after the optical fiber is inserted into the sleeve, it is fixed to the sleeve at the opening of the sleeve's horn-shaped cavity by adhesive, and the cavity between the first reflective surface and the second reflective surface remains sealed after being glued.

[0027] The beneficial effects of this invention are as follows: The sound pressure sensor of this invention changes the shape of the diaphragm, and the arrayed diaphragm has several protrusions at the other end of the second reflective surface. These protrusions are arrayed on the surface of the diaphragm. The design of these protrusions helps to increase the deflection change of the diaphragm under the action of sound waves, amplifying the influence of external sound pressure on the deflection of the center point of the compressed diaphragm, thereby enhancing the sensitivity of the sensor. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the sound pressure sensor device.

[0030] Figure 2 This is a schematic diagram of the cross-section of the array diaphragm in the acoustic pressure sensor, where the length 2r corresponds to the diaphragm diameter;

[0031] Figure 3 This is a schematic diagram of the sound pressure sensor device.

[0032] Figure 4 A comparison diagram showing the change in diaphragm deflection when comparing an array of diaphragms with a flat circular diaphragm;

[0033] Figure 5 This is a schematic diagram of the deformation of the all-quartz array diaphragm simulated using COMSOL in this invention;

[0034] Figure 6 This is a numerical analysis diagram of the frequency response of the array diaphragm structure calculated using COMSOL multiphysics simulation software in this invention;

[0035] Figure 7 The diagram shows the diaphragm deformation response of the array diaphragm sensor proposed in this invention under different sound pressure levels.

[0036] Figure 8 This is a schematic diagram of the deformation of the arrayed diaphragm and the flat circular diaphragm simulated using COMSOL in this invention; Detailed Implementation

[0037] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0038] like Figure 1 As shown: A sound pressure sensor based on the Fabry-Perot principle, comprising:

[0039] Sleeve 4, sleeve 4 includes a funnel-shaped cavity 3;

[0040] The optical fiber 5 is fixedly mounted on the sleeve 4 and located at the smaller end of the horn-shaped cavity 3. The end of the optical fiber 5 inside the horn-shaped cavity 3 includes a first reflective surface.

[0041] The array diaphragm 2 is fixedly mounted on the sleeve 4 and located at the end of the horn-shaped cavity 3 with a larger opening. The end of the array diaphragm 2 inside the horn-shaped cavity 3 includes a second reflective plane, and a Fabry-Perot cavity is formed between the first reflective surface and the second reflective surface.

[0042] The array diaphragm 2 has a plurality of protrusions 1 at the other end of the second reflective surface, and the plurality of protrusions 1 are arranged in an array on the surface of the diaphragm.

[0043] The sleeve 4 adopts a horn-shaped cavity 3, with one end having a smaller opening and the other end having a larger opening. The horn-shaped design helps guide sound waves into the sensor and improves the sensor's sensitivity. The optical fiber 5 is fixedly mounted on the sleeve 4, located at the end of the horn-shaped cavity 3 with the smaller opening. One end of the optical fiber 5 includes a first reflective surface for reflecting light.

[0044] An array diaphragm 2 is fixedly mounted on a sleeve 4, located at the larger opening end of a horn-shaped cavity 3. One end of the array diaphragm 2 inside the cavity includes a second reflecting plane, forming a Fabry-Perot cavity with the first reflecting surface of the optical fiber 5. At the other end of the array diaphragm 2, several protrusions 1 are arranged in an array on the diaphragm surface. The design of these protrusions 1 helps to increase the deflection change of the diaphragm under the action of sound waves, thereby enhancing the sensor's sensitivity. This design utilizes the Fabry-Perot principle to measure sound pressure, sensing changes in sound pressure through the interference effect between the optical fiber 5 and the array diaphragm 2. The combination of the horn shape of the sleeve 4, the reflecting surface of the optical fiber 5, and the protrusion design of the array diaphragm 2 improves the sensor's sensitivity and performance.

[0045] In the initial state, the distance between the array diaphragm 2 and the end face of the optical fiber 5 remains fixed. When using the acoustic pressure sensor, acoustic pressure is first applied to the array diaphragm 2, causing the deflection of the diaphragm center point to change after being subjected to acoustic pressure. This results in a change in the distance between the two reflecting surfaces, which in turn causes a change in the cavity length of the interference. Finally, the magnitude of the external pressure can be reflected by measuring the change in signal intensity caused by the change in cavity length.

[0046] In this embodiment, the protrusions 1 are arranged in a grid pattern.

[0047] The protrusions 1 are arranged in a grid pattern, forming a grid-shaped structure on the surface of the array diaphragm 2. This grid-shaped design increases the surface area of ​​the diaphragm, making it more susceptible to acoustic waves and resulting in greater deflection. The grid-shaped arrangement of the protrusions 1 more effectively releases internal stress within the diaphragm and increases its deflection variation, thereby improving the sensor's performance and stability. By designing the protrusions 1 in a grid-shaped array, the sensor can achieve higher sensitivity and performance while maintaining structural stability.

[0048] In this arrangement, protrusions 1 are evenly spaced on any diameter of the surface of the array diaphragm 2, and along any direction perpendicular to the diameter, the number of protrusions 1 gradually decreases from the middle to both sides.

[0049] The evenly spaced protrusions ensure a uniform distribution of sound pressure sensing capability across the entire diaphragm surface, improving the overall sensitivity of the sensor.

[0050] The design, with the number of sensors gradually decreasing from the center to the sides, makes the sensor's ability to sense sound pressure gradually weaken at different locations, which better matches the characteristics of sound pressure distribution in real-world scenarios and enhances the sensor's response performance to specific sound pressure ranges. Through this optimized design, the sensor can achieve higher sensitivity and performance while maintaining structural stability, improving its reliability and applicability in practical applications.

[0051] As a preferred embodiment of the above, the protrusion 1 includes any one of a cube structure, a cuboid structure, a cylindrical structure, a frustum structure, a cone structure, or a pyramid structure.

[0052] A cube structure features equilateral square protrusions, offering simplicity, stability, and ease of fabrication. A cuboid structure, with rectangular protrusions, is more directional than a cube and may provide better performance in specific scenarios. A cylindrical structure, with cylindrical protrusions and a circular cross-section, provides a more uniform force distribution, suitable for applications requiring more uniform sensitivity. A frustum structure, with polygonal cross-section protrusions, offers a larger surface area and more force application points, suitable for applications requiring increased sensitivity. A frustum of cones, with conical protrusions, provides greater deflection variation, enhancing the sensor's sensing capabilities. A pyramidal structure, with polyhedral protrusions, may offer more force directions and greater deflection variation, further enhancing sensor performance. Based on specific application requirements and performance specifications, a suitable protrusion structure can be selected to design the sensor to achieve optimal performance and effectiveness.

[0053] The sleeve 4 and the array diaphragm 2 are both made of quartz. Quartz is an excellent material with superior optical properties and chemical stability, making it very suitable for manufacturing optical sensors. Using quartz ensures that the sensor has good high-temperature resistance and corrosion resistance, while also maintaining good optical transparency and stability, which is beneficial for maintaining the long-term stability and accuracy of the sensor.

[0054] In this embodiment, the diameter of the smaller opening end of the flared cavity 3 of the sleeve 4 is 2-3 micrometers larger than the diameter of the optical fiber 5. This design helps ensure that the optical fiber 5 can be easily inserted into the sleeve 4 and held in a stable position within the cavity.

[0055] This embodiment also includes a method for manufacturing a sound pressure sensor based on the Fabry-Perot principle. The manufacturing of the sound pressure sensor as described above includes the following steps:

[0056] Using a multi-laser integrated additive and subtractive manufacturing process, patterns are etched onto the surface of a circular diaphragm to form an array of protrusions 1, thus forming an array diaphragm 2. These protrusions 1 can be designed in any preferred manner, such as a grid pattern, equal spacing, or different protrusion types.

[0057] The sleeve 4 is manufactured, and the larger opening end of the flared cavity 3 of the sleeve 4 needs to be adapted to the bonding of the array diaphragm 2. The manufacturing of the sleeve 4 needs to ensure its fit and stability with the array diaphragm 2.

[0058] At the end of the horn-shaped cavity 3 of the sleeve 4 with a larger opening, the array diaphragm 2 is bonded and fixed, and the end with the protrusion 1 is located outside the cavity during bonding.

[0059] Insert the optical fiber 5 into the smaller opening end of the horn-shaped cavity 3 of the sleeve 4, ensuring that the first reflecting surface of the optical fiber 5 is directly aligned with the center of the second reflecting surface of the array diaphragm 2, and fix it in place, maintaining a consistent distance between the optical fiber 5 and the array diaphragm 2. When fixing the optical fiber 5, ensure that the distance between the optical fiber 5 and the array diaphragm 2 remains consistent to guarantee the stability and accuracy of the interference effect.

[0060] An external spectrometer is used to obtain the optimal interference fringes, and the cavity length of the Fabry-Perot interferometer is fixed.

[0061] Patterns are etched onto the surface of a circular diaphragm using a multi-laser integrated additive and subtractive manufacturing process, including the following steps:

[0062] Circular films were fabricated using carbon dioxide laser additive manufacturing technology with molten silicon dioxide as the raw material.

[0063] The protrusions are etched in a grid pattern on the film using a picosecond laser.

[0064] Using carbon dioxide laser additive manufacturing technology, circular films are fabricated using molten silicon dioxide as the raw material. This step involves melting and solidifying the silicon dioxide material using a laser to form a circular film of the desired shape.

[0065] Picosecond lasers are used to etch a grid-like array of protrusions 1 onto the surface of a diaphragm. The high-energy pulses and short pulse widths of the picosecond laser enable precise etching of the diaphragm surface, forming the desired protrusion 1 structure. This combination of steps, utilizing different types of lasers and processing techniques, allows for precise fabrication of a circular diaphragm surface, producing an array diaphragm 2 with the grid-like array of protrusions 1. Such a diaphragm structure can improve the sensitivity and performance of the sensor, thus better enabling the manufacture of acoustic pressure sensors.

[0066] As a preferred embodiment of the above, the coating layer of the optical fiber 5 is removed before it is inserted into the sleeve 4.

[0067] Removing the coating reduces the diameter of the optical fiber 5, making it more suitable for insertion into the sleeve 4. This reduces the gap between the optical fiber 5 and the sleeve 4, lowering the risk of dimensional mismatch during assembly. Removing the coating also makes the optical fiber 5 more sensitive, facilitating the transmission and detection of optical signals. This improves the performance and accuracy of the sensor.

[0068] Sometimes, the coating on fiber 5 can affect sensor performance, such as increasing optical signal attenuation or introducing additional noise. Removing the coating can avoid these effects, making the sensor's performance more stable and reliable. Therefore, removing the coating on fiber 5 before manufacturing a sound pressure sensor is an effective optimization strategy that helps improve the sensor's performance and reliability.

[0069] As a preferred embodiment of the above, after the optical fiber 5 is inserted into the sleeve 4, it is fixed to the optical fiber 5 at the opening of the horn-shaped cavity 3 of the sleeve 4 by adhesive, and the cavity between the first reflective surface and the second reflective surface is kept sealed after adhesive.

[0070] Fixing the optical fiber 5 with adhesive ensures stable positioning between the fiber 5 and the sleeve 4, preventing positional changes caused by vibration or movement, thus guaranteeing the sensor's performance and accuracy. Adhesive bonding also ensures the cavity between the first and second reflecting surfaces remains sealed. This prevents external impurities from entering the cavity, avoiding interference with the interference effect and ensuring the sensor's measurement accuracy. Adhesive bonding is a simple and easy method, with low production costs and the ability to quickly complete the fixing process, improving production efficiency. Adhesive bonding typically offers high reliability and durability, ensuring a strong connection between the optical fiber 5 and the sleeve 4 and maintaining stability over extended periods.

[0071] Therefore, fixing the optical fiber 5 with adhesive can effectively improve the performance and reliability of the acoustic pressure sensor and ensure its stable operation in various application environments.

[0072] like Figure 2 As shown, in this embodiment, the base thickness of the wellhead array diaphragm 2 is designed to be h1, the structure of the protrusion 1 is a cube of h2, and the width between the cubes of the protrusion 1 is h3. Therefore, the bending stiffness... Where h is the total thickness of the diaphragm, E is the Young's modulus of the diaphragm, and μ is the Poisson's ratio of the material. Once the specific material of the diaphragm is determined, E and μ are fixed at constant values, so the bending stiffness of the material can be changed by altering the thickness of the diaphragm. The wellhead array diaphragm 2 is fabricated using a multi-laser integrated additive and subtractive manufacturing platform.

[0073] Figure 3 This is a schematic diagram of the principle of a sound pressure sensor. When the array diaphragm 2 is subjected to sound pressure, the deflection of the center point of the diaphragm changes after being subjected to sound pressure, which causes the distance between the two reflecting surfaces to change, thereby changing the length of the interference cavity. Finally, the magnitude of the external pressure can be reflected by measuring the change in signal intensity caused by the change in cavity length.

[0074] Figure 4 and Figure 5The figure shows a schematic diagram of the diaphragm deformation of a wellhead array diaphragm 2 and a flat circular diaphragm with the same parameters under the same sound pressure, simulated by COMSOL.

[0075] Figure 6 The figure shows the frequency response analysis of the wellhead array structure using COMSOL multiphysics simulation software. As can be seen from the figure, the intrinsic frequency of the fabricated wellhead array structure is around 1000Hz. Based on the freedom of microfabrication technology, wellhead array diaphragms of different sizes and radii can be fabricated to change the intrinsic frequency, thereby realizing the measurement of sound pressure signals of different frequencies.

[0076] Figure 7 The figure shows the deformation response obtained by applying different sound pressures to the wellhead array diaphragm 2. It can be seen that within the deformation tolerance range of the wellhead array diaphragm 2, the deformation of the wellhead array diaphragm 2 is linearly related to the magnitude of the applied sound pressure.

[0077] Figure 8 The figure shows a comparison of the deformation results of the wellhead array diaphragm 2 and the flat circular diaphragm obtained through simulation. It can be seen from the figure that, under the same parameters, the deformation of the wellhead array diaphragm 2 proposed in this invention is 8.3 times that of the flat circular diaphragm.

[0078] By fabricating a wellhead array on a flat diaphragm, the internal stress of the diaphragm can be released. Typically, changing the depth and period of the well pattern significantly affects the diaphragm's sensitivity performance. Further improvements in diaphragm sensitivity require simulation using parametric scanning with COMSOL.

[0079] The acoustic pressure sensor of this invention amplifies the influence of external acoustic pressure on the deflection of the center point of the pressurized diaphragm by changing the shape and arrangement of the diaphragm, thereby improving the measurement sensitivity. COMSOL simulation can prove that the diaphragm center deformation of the designed wellhead array diaphragm is 8.3 times that of a flat circular diaphragm with the same parameters, thus improving the sensor sensitivity.

[0080] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. "A plurality of" means two or more, unless otherwise explicitly specified.

[0081] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0082] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0083] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as will be understood by those skilled in the art to which embodiments of the invention pertain.

Claims

1. A sound pressure sensor based on the Fabry-Perot principle, characterized in that, include: A sleeve, the sleeve comprising a funnel-shaped cavity; An optical fiber is fixedly disposed on the sleeve and located at the end of the horn-shaped cavity with a smaller opening. The end of the optical fiber inside the horn-shaped cavity includes a first reflective surface. An array diaphragm is fixedly disposed on the sleeve and located at the end of the larger opening of the horn-shaped cavity. The array diaphragm includes a second reflective plane at one end inside the horn-shaped cavity, and a Fabry-Perot cavity is formed between the first reflective surface and the second reflective surface. The array diaphragm has a plurality of protrusions at the other end of the second reflective surface, and the plurality of protrusions are arrayed on the surface of the diaphragm. The protrusions are arranged in a grid pattern; The protrusions are equally spaced on any diameter of the array diaphragm surface, and along any direction perpendicular to the diameter, the number of protrusions gradually decreases from the middle to both sides. The protrusion includes any one of the following structures: cube, cuboid, cylindrical, frustum, truncated cone, and pyramid.

2. The sound pressure sensor based on the Fabry-Perot principle according to claim 1, characterized in that, The sleeve and the array diaphragm are made of quartz.

3. The sound pressure sensor based on the Fabry-Perot principle according to claim 1, characterized in that, The diameter of the smaller end of the horn-shaped cavity opening of the sleeve is 2-3 micrometers larger than the diameter of the optical fiber.

4. A method for manufacturing a sound pressure sensor based on the Fabry-Perot principle, characterized in that, Manufacturing the sound pressure sensor as described in any one of claims 1 to 3 includes the following steps: Through multi-laser integrated additive and subtractive processing technology, patterns are etched on the surface of a circular diaphragm to form an array of protrusions, thus forming an array diaphragm; The sleeve is manufactured; The array diaphragm is bonded and fixed at the end of the horn-shaped cavity of the sleeve with a larger opening, and the end with the protrusion is located outside the cavity during bonding. Insert the optical fiber into the smaller end of the horn-shaped cavity of the sleeve, so that the first reflective surface of the optical fiber is directly opposite the center of the second reflective surface of the array diaphragm, and fix it so that the distance between the optical fiber and the array diaphragm is consistent. An external spectrometer is used to obtain the optimal interference fringes, and the cavity length of the Fabry-Perot interferometer is fixed.

5. The method for manufacturing a sound pressure sensor based on the Fabry-Perot principle according to claim 4, characterized in that, The process of etching a pattern onto the surface of a circular diaphragm using a multi-laser integrated additive and subtractive manufacturing technique includes the following steps: Circular films were fabricated using carbon dioxide laser additive manufacturing technology with molten silicon dioxide as the raw material. Picosecond lasers are used to etch protrusions arranged in a grid pattern on a film.

6. The method for manufacturing a sound pressure sensor based on the Fabry-Perot principle according to claim 4, characterized in that, Before the optical fiber is inserted into the sleeve, the coating layer of the optical fiber is removed.

7. The method for manufacturing a sound pressure sensor based on the Fabry-Perot principle according to claim 4, characterized in that, After the optical fiber is inserted into the sleeve, it is fixed to the sleeve at the opening of the sleeve's horn-shaped cavity by adhesive, and the cavity between the first reflective surface and the second reflective surface remains sealed after being glued.

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