Temperature-insensitive F-P interference type optical fiber microphone probe structure
By using all quartz material and a five-dimensional adjustment frame clamping sleeve, the structure of the fiber optic microphone probe is adjusted, and the problem of the F-P interference cavity being susceptible to temperature is solved, and a temperature-insensitive probe structure is realized, which improves the yield rate and reduces costs.
Patent Information
- Application Number
- CN202411636534.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-03-04
AI Technical Summary
The F-P interference cavity of existing F-P interference fiber optic microphones is easily affected by external factors such as temperature, resulting in temperature noise and affecting its practicality.
The casing is clamped through the first and second five-dimensional adjustment frames, the spacing between the diaphragm and the end surface of the optical fiber is adjusted, and the casing is welded and connected by a carbon dioxide laser to form a temperature-insensitive F-P interference fiber microphone probe structure.
It effectively reduces the impact of temperature on the length of F-P interference cavity, improves the temperature insensitivity of the probe, simplifies the production process, reduces costs and improves the yield.
Smart Images
Figure CN119562199A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of optical fiber sensing technology, and in particular to a temperature-insensitive FP interference optical fiber microphone probe structure. Background Art
[0002] As a new type of microphone, the fiber optic microphone has the advantages of high sensitivity, strong anti-electromagnetic interference ability, low transmission loss, and long transmission distance. The higher sensitivity can increase the range of the acoustic signal detection and identification system; the anti-electromagnetic interference ability enables it to be used in special environments such as strong radiation, high temperature and high humidity; and it can be deployed in complex terrain environments for long-distance target detection, and has great application potential in transformer detection, gas pipeline monitoring, border early warning monitoring and other fields.
[0003] Compared with other types of fiber optic microphones, FP interferometric fiber optic microphones have the advantages of high sensitivity and easy formation of large-scale arrays. However, the FP interferometric cavity is easily affected by external factors such as temperature, thereby superimposing temperature noise and affecting its practical application.
[0004] At present, the commonly used direct solution to solve the temperature sensitivity problem of the FP interferometer cavity is to develop the optical fiber ferrule through composite materials, change the thermal expansion coefficient of the optical fiber ferrule, so that when the external temperature changes, the length of the FP interferometer cavity remains unchanged. The disadvantage of this method is that it requires very high processing accuracy of the structural parts, the yield is low, and it requires manual repeated tests, resulting in high costs and cannot be further mass-produced.
[0005] In view of this, how to provide a temperature-insensitive FP interferometric fiber optic microphone probe structure so as to further improve the yield and reduce the cost in the mass production process of fiber optic microphone products has become a technical problem that urgently needs to be solved. Summary of the invention
[0006] The embodiment of the present application provides a temperature-insensitive FP interferometric fiber optic microphone probe structure, which is used to solve the problem that the FP interferometric cavity used in the existing FP interferometric fiber optic microphone is easily affected by external factors such as temperature.
[0007] In a first aspect of an embodiment of the present application, a temperature-insensitive FP interference fiber microphone probe structure is provided, comprising: a diaphragm for sensing sound vibration, a housing, a sleeve and an optical fiber, wherein:
[0008] The shell structure of the housing is made of all quartz material;
[0009] The sleeve comprises an inner sleeve, a middle sleeve and an outer sleeve, wherein the inner sleeve is used to place the optical fiber with the coating removed; the middle sleeve is used to place the inner sleeve, and the middle sleeve is clamped by a first five-dimensional adjustment frame; the outer sleeve is used to place the middle sleeve, and the outer sleeve is clamped by a second five-dimensional adjustment frame;
[0010] The diaphragm adopts a diaphragm made of a micromachining process based on a silicon wafer and is connected to the outer sleeve. The size of the corresponding diameter is determined based on the outer diameter of the middle sleeve. The spacing between the diaphragm and the optical fiber end face is determined by adjusting the first five-dimensional adjustment frame and the second five-dimensional adjustment frame. When the spacing meets the preset spacing, the inner sleeve and the outer sleeve are welded to obtain a temperature-insensitive FP interference type optical fiber microphone probe.
[0011] In an optional embodiment, the inner sleeve has an inner diameter of 130 μm and an outer diameter of 1 mm;
[0012] The middle sleeve has an inner diameter of 1.1 μm and an outer diameter of 6 mm, and the inner diameter of the middle sleeve is larger than the outer diameter of the inner sleeve;
[0013] The outer sleeve has an inner diameter of 6.1 mm and an outer diameter of 8 to 10 mm. The inner diameter of the outer sleeve is larger than the outer diameter of the middle sleeve, and the outer diameter of the outer sleeve can bond the diaphragm and the outer sleeve.
[0014] In an optional embodiment, a membrane is bonded to the front end of the outer sleeve.
[0015] In an optional embodiment, the optical fiber and the sleeve, and the inner sleeve, the middle sleeve and the outer sleeve are connected by carbon dioxide laser welding.
[0016] In an optional embodiment, the optical fiber with the coating removed is welded to the inner sleeve by spot welding, and the end face is ground into a flat surface;
[0017] The inner sleeve with the optical fiber is welded and connected to the middle sleeve by a carbon dioxide laser, and the end surface is ground into a flat surface.
[0018] In an optional embodiment, the diaphragm is welded to the outer sleeve via a carbon dioxide laser, wherein the diaphragm is supported by silicon wafers on all sides.
[0019] The present application provides a temperature-insensitive FP interference type fiber optic microphone probe structure, comprising: a diaphragm for sensing sound vibration, an outer shell, a sleeve and an optical fiber, wherein the shell structure of the outer shell is made of all-quartz material; the sleeve comprises an inner sleeve, a middle sleeve and an outer sleeve, wherein the inner sleeve is used to place the optical fiber with the coating removed; the middle sleeve is used to place the inner sleeve, and the middle sleeve is clamped by a first five-dimensional adjustment frame; the outer sleeve is used to place the middle sleeve, and the outer sleeve is clamped by a second five-dimensional adjustment frame; the diaphragm is connected to the outer sleeve, and the size of the corresponding diameter is determined based on the outer diameter of the middle sleeve, wherein the spacing between the diaphragm and the end face of the optical fiber is determined by adjusting the first five-dimensional adjustment frame and the second five-dimensional adjustment frame, and when the spacing meets the preset spacing, the inner sleeve and the outer sleeve are welded to obtain a temperature-insensitive FP interference type fiber optic microphone probe.
[0020] The temperature-insensitive FP interference fiber microphone probe structure provided in the embodiment of the present application ensures the temperature-insensitive property of the shell by adopting quartz material with the same temperature coefficient; its diaphragm material adopts silicon and silicon compounds, even if its temperature coefficient is slightly different from quartz, but it is located at the end face of the probe structure, and the change of cavity length due to temperature change is very small, which successfully minimizes the influence of temperature; the structure used in the present application is simple, the material is relatively single, and it is easy to realize mass production.
[0021] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, which can be implemented in accordance with the contents of the specification, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:
[0023] Figure 1 A schematic structural diagram of a temperature-insensitive FP interferometric fiber optic microphone probe structure provided in an embodiment of the present application. DETAILED DESCRIPTION
[0024] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.
[0025] See also Figure 1 , Figure 1 The schematic diagram of the structure of a temperature-insensitive FP interferometric fiber optic microphone probe structure provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the fiber optic microphone probe structure includes: a diaphragm 1 for sensing sound vibration, a housing, a sleeve and an optical fiber 2, wherein:
[0026] The shell structure of the housing is made of all quartz material;
[0027] The sleeve comprises an inner sleeve 3, a middle sleeve 4 and an outer sleeve 5, wherein the inner sleeve is used to place the optical fiber with the coating removed; the middle sleeve is used to place the inner sleeve, and the middle sleeve is clamped by a first five-dimensional adjustment frame; the outer sleeve is used to place the middle sleeve, and the outer sleeve is clamped by a second five-dimensional adjustment frame;
[0028] The diaphragm adopts a diaphragm made of a micromachining process based on a silicon wafer and is connected to the outer sleeve. The size of the corresponding diameter is determined based on the outer diameter of the middle sleeve. The spacing between the diaphragm and the optical fiber end face is determined by adjusting the first five-dimensional adjustment frame and the second five-dimensional adjustment frame. When the spacing meets the preset spacing, the inner sleeve and the outer sleeve are welded to obtain a temperature-insensitive FP interference type optical fiber microphone probe.
[0029] In an embodiment of the present application, the inner sleeve has an inner diameter of 130 microns and an outer diameter of 1 millimeter; the middle sleeve has an inner diameter of 1.1 microns and an outer diameter of 6 millimeters, and the inner diameter of the middle sleeve is larger than the outer diameter of the inner sleeve; the outer sleeve has an inner diameter of 6.1 millimeters and an outer diameter of 8 to 10 millimeters, and the inner diameter of the outer sleeve is larger than the outer diameter of the middle sleeve, and the outer diameter of the outer sleeve can bond the diaphragm and the outer sleeve.
[0030] In actual applications, three different sizes of quartz glass sleeves are used. The thinner inner sleeve has an inner diameter of 130um and an outer diameter of 1mm, which is used to place the optical fiber without the coating layer. The thicker middle sleeve has an inner diameter of 1.1um and an outer diameter of 6mm, which is used to place the inner sleeve. The outer sleeve has an inner diameter of 6.1mm and an outer diameter of 8 to 10mm, which is used to place the middle sleeve. The front end of the outer sleeve is bonded with a film.
[0031] Among them, the variable range of the size of the inner sleeve is not large, because when the inner diameter is small, the outer diameter cannot be too large due to the influence of the processing technology; the inner diameter of the middle sleeve should be slightly larger than the outer diameter of the inner sleeve, and when the inner diameter is larger than 1mm, the outer diameter of the sleeve can be made relatively large, and the outer diameter of the middle sleeve determines the effective action area of the diaphragm. The larger the outer diameter, the larger the diaphragm, the greater the mechanical sensitivity of the diaphragm, and the smaller the resonant frequency. Conversely, the smaller the outer diameter of the middle sleeve, the smaller the diaphragm size, the lower the mechanical sensitivity, and the higher the resonant frequency.
[0032] The inner diameter of the outer sleeve is slightly larger than the outer diameter of the middle sleeve, and the outer diameter of the outer sleeve needs to ensure effective bonding between the diaphragm and the outer sleeve.
[0033] In the embodiment of the present application, a membrane is bonded to the front end of the outer sleeve.
[0034] In the embodiment of the present application, the optical fiber and the sleeve, and the inner sleeve, the middle sleeve and the outer sleeve are connected by carbon dioxide laser welding.
[0035] In an embodiment of the present application, the optical fiber with the coating removed is welded to the inner sleeve by spot welding, and the end face is ground into a plane; the inner sleeve with the optical fiber is welded to the middle sleeve by a carbon dioxide laser, and the end face is ground into a plane.
[0036] In actual applications, the connection between the optical fiber and the sleeve, and between the sleeves is welded by a carbon dioxide laser. First, remove the coating of the optical fiber, weld it to the inner sleeve by spot welding, and grind the end face into a flat surface. Then insert the inner sleeve with the optical fiber into the middle sleeve, and the inner sleeve extends out a small size. The inner and middle sleeves are welded by a carbon dioxide laser, and then the end face is grinded flat.
[0037] In an embodiment of the present application, the diaphragm is welded to the outer sleeve via a carbon dioxide laser, wherein the diaphragm is supported by silicon wafers on all sides.
[0038] In actual applications, the diaphragm uses a micro-mechanical structure diaphragm based on silicon wafers, and is supported by silicon wafers on all sides. The end face of the outer sleeve is polished flat, and the processed silicon wafer diaphragm is placed on the end face of the outer sleeve, and the silicon wafer diaphragm and the end face of the outer sleeve are bonded together by a carbon dioxide laser.
[0039] The middle sleeve and the outer sleeve are clamped respectively with a five-dimensional adjustment frame, and the distance between the optical fiber end face and the diaphragm, that is, the cavity length of the FP cavity, is adjusted by the five-dimensional adjustment frame. After adjusting to the required distance, a carbon dioxide laser is used to weld the two sleeves together to complete the development of the fiber optic microphone probe.
[0040] The temperature-insensitive FP interferometric fiber optic microphone probe structure provided by the embodiment of the present application ensures the temperature-insensitive property of the shell by using quartz material with the same temperature coefficient; the diaphragm material is silicon and silicon compounds, even if its temperature coefficient is slightly different from that of quartz, it is located at the end face of the probe structure, and the cavity length change caused by temperature change is very small, successfully minimizing the influence of temperature. The structure used in the present invention is simple, the material is relatively simple, and it is easy to realize mass production.
[0041] It should be noted that the above is a description of a specific embodiment of the present specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the embodiments of the present specification.
[0042] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0043] The preferred embodiments of this specification disclosed above are only used to help explain this specification. The optional embodiments do not describe all the details in detail, nor do they limit the invention to only the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of the embodiments of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the embodiments of this specification, so that technicians in the relevant technical field can well understand and use this specification. This specification is only limited by the claims and their full scope and equivalents.
Claims
1. A temperature-insensitive FP interferometric fiber optic microphone probe structure, characterized in that: include: A diaphragm, a housing, a sleeve and an optical fiber for sensing sound vibrations, wherein: The shell structure of the housing is made of all quartz material; The sleeve comprises an inner sleeve, a middle sleeve and an outer sleeve, wherein the inner sleeve is used to place the optical fiber with the coating removed; the middle sleeve is used to place the inner sleeve, and the middle sleeve is clamped by a first five-dimensional adjustment frame; the outer sleeve is used to place the middle sleeve, and the outer sleeve is clamped by a second five-dimensional adjustment frame; The diaphragm adopts a diaphragm made of a micromachining process based on a silicon wafer and is connected to the outer sleeve. The size of the corresponding diameter is determined based on the outer diameter of the middle sleeve. The spacing between the diaphragm and the optical fiber end face is determined by adjusting the first five-dimensional adjustment frame and the second five-dimensional adjustment frame. When the spacing meets the preset spacing, the inner sleeve and the outer sleeve are welded to obtain a temperature-insensitive FP interference type optical fiber microphone probe.
2. A temperature-insensitive FP interferometric fiber optic microphone probe structure according to claim 1, characterized in that: The inner sleeve has an inner diameter of 130 μm and an outer diameter of 1 mm; The middle sleeve has an inner diameter of 1.1 μm and an outer diameter of 6 mm, and the inner diameter of the middle sleeve is larger than the outer diameter of the inner sleeve; The outer sleeve has an inner diameter of 6.1 mm and an outer diameter of 8 to 10 mm. The inner diameter of the outer sleeve is larger than the outer diameter of the middle sleeve, and the outer diameter of the outer sleeve can bond the diaphragm and the outer sleeve.
3. The temperature-insensitive FP interferometric fiber optic microphone probe structure according to claim 1, characterized in that: The front end of the outer sleeve is bonded with a membrane.
4. The temperature-insensitive FP interferometric fiber optic microphone probe structure according to claim 1, characterized in that: The optical fiber and the sleeve, and the inner sleeve, the middle sleeve and the outer sleeve are connected by carbon dioxide laser welding.
5. The temperature-insensitive FP interferometric fiber optic microphone probe structure according to claim 4, characterized in that: The optical fiber with the coating removed is welded to the inner sleeve by spot welding, and the end surface is ground into a flat surface; The inner sleeve with the optical fiber is welded and connected to the middle sleeve by a carbon dioxide laser, and the end surface is ground into a flat surface.
6. The temperature-insensitive FP interferometric fiber optic microphone probe structure according to claim 1, characterized in that: The diaphragm is welded and connected to the outer sleeve by a carbon dioxide laser, wherein the diaphragm is supported by silicon wafers on all sides.