CN112729600A - Temperature and air pressure testing method for FBG (fiber Bragg Grating) combined with optical fiber microspheres by femtosecond laser direct writing - Google Patents
Temperature and air pressure testing method for FBG (fiber Bragg Grating) combined with optical fiber microspheres by femtosecond laser direct writing Download PDFInfo
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- CN112729600A CN112729600A CN202011431494.0A CN202011431494A CN112729600A CN 112729600 A CN112729600 A CN 112729600A CN 202011431494 A CN202011431494 A CN 202011431494A CN 112729600 A CN112729600 A CN 112729600A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
- G01K11/00—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00
- G01K11/32—Measuring temperature based upon physical or chemical changes not covered by groups G01K3/00, G01K5/00, G01K7/00 or G01K9/00 using changes in transmittance, scattering or luminescence in optical fibres
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L11/00—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00
- G01L11/02—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00 by optical means
- G01L11/025—Measuring steady or quasi-steady pressure of a fluid or a fluent solid material by means not provided for in group G01L7/00 or G01L9/00 by optical means using a pressure-sensitive optical fibre
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/02057—Optical fibres with cladding with or without a coating comprising gratings
- G02B6/02076—Refractive index modulation gratings, e.g. Bragg gratings
- G02B6/02123—Refractive index modulation gratings, e.g. Bragg gratings characterised by the method of manufacture of the grating
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Abstract
The invention relates to a temperature and air pressure test method for a femtosecond laser direct writing Bragg Fiber Grating (FBG) combined optical Fiber microsphere. The sensor mainly comprises FBG prepared by femtosecond laser and an optical fiber microsphere structure prepared by combining chemical corrosion with arc discharge, and can realize simultaneous measurement of temperature and air pressure. The femtosecond laser direct-writing FBG manufactured by adopting the technical scheme provided by the invention is combined with the optical fiber microsphere temperature and air pressure sensor to form an all-fiber structure, can avoid electromagnetic interference, is high-temperature resistant, and can realize simultaneous measurement of temperature and refractive index. Meanwhile, the structure and the manufacturing process are simple, the reliability is good, and the sensitivity is high.
Description
Technical Field
The invention belongs to the field of optical fiber sensing devices, and particularly relates to a temperature and air pressure testing method for bonding a femtosecond laser direct writing FBG (fiber Bragg Grating) with an optical fiber microsphere.
Background
The optical fiber sensor has a plurality of excellent characteristics, can realize the measurement work under the complex environment and has very wide application value. The optical fiber has the characteristics of electromagnetic interference resistance, radiation resistance, high sensitivity, light weight, insulation, explosion resistance, corrosion resistance and the like, and the optical fiber has small size and good optical transmission performance. The Fiber Bragg Grating (FBG) is a common sensing device, has the advantages of simple structure, small volume, large dynamic range, high sensitivity and the like, and is widely concerned in important fields of aerospace, bridge water conservancy, perimeter security, biomedicine and the like. An FBG is a grating-like structure with a periodic distribution of spatial phases formed in the core, which essentially functions to form a narrow band filter or mirror in the core. When the external temperature changes, the relative displacement between the grating structures can be influenced by the expansion with heat and the contraction with cold of the optical fiber material, so that the reflection wavelength shifts. By demodulating the range of wavelength drift, the change of the outside temperature can be intuitively calculated.
However, how to change the limitation of single-point detection of the conventional fiber FBG sensor and extend the range of the detection object is the development direction of the fiber sensor. The common optical fiber FBG sensor is of a cylindrical structure and cannot directly detect the pressure of an environment to be detected. The optical fiber microsphere structure is prepared by combining chemical corrosion with arc discharge, and the change of the external air pressure acts on the sphere, so that the optical path difference of light transmitted in the fiber core between the two reflecting surfaces is changed. The sensing of the external air pressure can be realized through the density change of the interference fringes of the optical fiber microspheres. FBG is prepared by femtosecond laser direct writing, an optical fiber microsphere structure is prepared by combining chemical corrosion with arc discharge, the two optical fiber structures are combined for measurement, the cross interference in multi-parameter measurement is avoided, and the dual-parameter measurement of temperature and air pressure is realized.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a temperature and air pressure testing method for combining a femtosecond laser direct writing FBG with an optical fiber microsphere. FBG that uses femto second laser preparation can be high temperature resistant, and the optic fibre microballon structure that uses chemical corrosion to combine the arc discharge preparation can realize atmospheric pressure sensing, therefore this structure can expand sensing parameter, realizes the measurement of temperature and atmospheric pressure simultaneously. The sensor is high in reliability, when the sensor is used, the part where the sensor is located is only required to be placed in an environment to be measured, the other end of the sensor is connected with the spectrometer, real-time double-parameter measurement of a test system can be completed, and the applicability of the device is improved.
In order to solve the technical problems, the invention adopts the technical scheme that: a femtosecond laser direct writing FBG combined optical fiber microsphere preparation method comprises the following steps:
(a) preparing a Bragg fiber grating by femtosecond laser, and placing an SMF-28E fiber on a three-dimensional moving platform to ensure clear visual field in step a 1; step a2, focusing femtosecond laser spots on a fiber core of the SMF-28E fiber, and preparing a Bragg fiber grating in the fiber core area by adopting a direct writing mode;
(b) b1, removing a coating layer from the end face of the single mode optical fiber, wiping with alcohol, cutting flat, and placing in hydrofluoric acid solution for end face corrosion; b2, placing the corroded optical fiber and the ordinary flat-cut optical fiber into a fusion splicer, and changing the discharge amount and the discharge time by adopting a fiber core alignment mode to finish the preparation of the optical fiber microsphere structure;
(c) preparing an optical fiber FBG combined microsphere structure, and cascading the femtosecond laser direct-writing Bragg optical fiber grating and the optical fiber microsphere structure through high-temperature arc discharge of a welding machine to prepare the optical fiber sensor.
Preferably, the concentration of the hydrofluoric acid solution is 5% -40%.
A temperature test method for bonding a femtosecond laser direct writing FBG (fiber Bragg Grating) with an optical fiber microsphere comprises the following steps: 301, placing an optical fiber sensor on the surface of a heating table, wherein the optical fiber sensor is connected with a light source and an optical fiber sensing analyzer through an optical fiber circulator; step 302, changing the temperature of the heating table, performing temperature sensing test on the optical fiber sensor, and transmitting the reflection interference spectrum of the FBG to the optical fiber sensing analyzer by using the optical fiber circulator to form a reflection spectrum spectral line.
An air pressure test method for bonding a femtosecond laser direct writing FBG (fiber Bragg Grating) with an optical fiber microsphere comprises the following steps of: step 401, placing an optical fiber sensor in a vacuum box, wherein the optical fiber sensor is connected with a light source and an optical fiber sensing analyzer through an optical fiber circulator; step 402, changing the ambient air pressure in the vacuum box, performing air pressure sensing test on the optical fiber sensor, and transmitting the reflection interference spectrum of the optical fiber FBG to the optical fiber sensing analyzer through the optical fiber circulator to form a reflection spectrum spectral line.
Preferably, the light source adopts ASE light source with the wave band range of 1520 and 1610 nm.
Preferably, when the external temperature changes, the reflection spectrum spectral line can shift.
Preferably, when the external air pressure changes, the spectral lines of the reflection spectrum shift.
Compared with the prior art, the invention has the beneficial effects that: the femtosecond laser direct-writing FBG manufactured by the technical method provided by the invention is combined with the temperature and air pressure test method of the optical fiber microsphere, and the all-fiber structure is adopted, so that the influence of electromagnetic interference on the detection result can be avoided. FBG that uses femto second laser preparation can be high temperature resistant, and the optic fibre microballon structure that uses chemical corrosion to combine the arc discharge preparation can realize atmospheric pressure sensing, therefore this structure can expand sensing parameter, realizes the measurement of temperature and atmospheric pressure simultaneously. The sensor has high reliability, and when the sensor is used, the part where the sensor is located is only required to be placed in an environment to be measured, and the other end of the sensor is connected with the spectrometer to complete real-time double-parameter measurement of a test system.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
Drawings
Further objects, features and advantages of the present invention will become apparent from the following description of embodiments of the invention, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram illustrating the processing principle of FBG prepared by femtosecond laser according to the invention;
FIG. 2 schematically shows a reflection spectrum of an optical fiber FBG structure of the present invention;
FIG. 3 is a schematic diagram of the chemical etching combined with arc discharge for preparing optical fiber microsphere structure according to the present invention;
FIG. 4 is a schematic representation of the reflection spectrum of the microsphere structure of the optical fiber according to the present invention;
FIG. 5 is a schematic diagram showing a cascading structure of FBGs and optical fiber microspheres according to the present invention;
FIG. 6 is a schematic representation of the reflection spectrum of the fiber optic sensor of the present invention;
FIG. 7 is a schematic diagram of a temperature sensing test system for an optical fiber sensor according to the present invention;
fig. 8 is a schematic diagram showing a temperature test spectrum of the optical fiber sensor according to the present invention.
Detailed Description
The objects and functions of the present invention and methods for accomplishing the same will be apparent by reference to the exemplary embodiments. However, the present invention is not limited to the exemplary embodiments disclosed below; it can be implemented in different forms. The nature of the description is merely to assist those skilled in the relevant art in a comprehensive understanding of the specific details of the invention.
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same or similar parts, or the same or similar steps.
The invention relates to a temperature and air pressure test method for a femtosecond laser direct writing Bragg Fiber Grating (FBG) combined optical Fiber microsphere. The sensor mainly comprises FBG prepared by femtosecond laser and an optical fiber microsphere structure prepared by combining chemical corrosion with arc discharge, and can realize simultaneous measurement of temperature and air pressure. The method for preparing the FBG by the femtosecond laser comprises the following steps: the SMF-28E optical fiber is placed on a three-dimensional moving platform, the visual field is clear, the femtosecond laser facula is focused to the fiber core, and the FBG is prepared in the fiber core area by adopting a direct writing mode. The method for preparing the optical fiber microsphere structure by combining chemical corrosion with arc discharge comprises the following steps: removing a coating layer from the end face of the single-mode optical fiber, wiping the end face with alcohol, flattening the end face, and putting the end face in a hydrofluoric acid solution with the concentration of 5-40% for end face corrosion; and (3) placing the corroded optical fiber and the common cut flat optical fiber into a welding machine, and changing the discharge amount and the discharge time by adopting a fiber core alignment mode to finish the manufacture of the optical fiber microsphere structure. The femtosecond laser direct-writing FBG manufactured by adopting the technical scheme provided by the invention is combined with the optical fiber microsphere temperature and air pressure sensor to form an all-fiber structure, can avoid electromagnetic interference, is high-temperature resistant, and can realize simultaneous measurement of temperature and refractive index. Meanwhile, the structure and the manufacturing process are simple, the reliability is good, and the sensitivity is high.
The method comprises the steps of preparing the FBG through femtosecond laser direct writing, and preparing an optical Fiber microsphere structure by adopting a chemical corrosion combined arc discharge method.
In order to achieve the above-listed purposes, the technical scheme adopted by the invention is as follows:
1. FBG prepared by femtosecond laser
A processing schematic diagram of FBG prepared based on femtosecond laser is shown in fig. 1, and the specific steps are as follows: the SMF-28E optical fiber is placed on a three-dimensional moving platform, the visual field is clear, the femtosecond laser facula is focused to the fiber core, and the FBG is prepared in the fiber core area by adopting a direct writing mode. The fiber FBG structure reflection spectrum is shown in fig. 2.
2. Optical fiber microsphere structure prepared by combining chemical corrosion with arc discharge
A method for preparing an optical fiber microsphere structure by combining chemical corrosion with arc discharge is shown in figure 3, and comprises the following steps: firstly, removing a coating layer from the end face of the single mode optical fiber, wiping the end face with alcohol, then cutting the end face to be flat, and putting the end face in a hydrofluoric acid solution with the concentration of 5% -40% for end face corrosion; and secondly, placing the corroded optical fiber and the common cut flat optical fiber into a fusion splicer, and changing the discharge amount and the discharge time by adopting a fiber core alignment mode to finish the manufacture of the optical fiber microsphere structure. The reflection spectrum of the optical fiber microsphere structure is shown in FIG. 4.
3. Optical fiber FBG combined microsphere structure prepared optical fiber sensor
The femtosecond laser direct-writing FBG and the optical fiber microsphere structure are cascaded through high-temperature arc discharge of a fusion splicer to realize the preparation of the sensor, the schematic structural diagram is shown in figure 5, and the reflection spectrum is shown in figure 6. The sensor combines the spectral characteristics of the FBG and the optical fiber microsphere structure, and can realize real-time measurement and monitoring of different parameters to be measured at different wavelength positions.
The temperature and air pressure test method of the femtosecond laser direct writing FBG combined with the optical fiber microsphere is shown in figure 7. The optical fiber sensor is arranged on the surface of the heating table or in the vacuum box and is connected with the light source and the optical fiber sensing analyzer through the optical fiber circulator. The light source adopts an ASE light source with the wave band range of 1520 and 1610nm, and the spectral analysis device adopts a spectral analyzer produced by Yokogawa company to collect the reflection spectrum in the experiment; the fiber optic circulator uses the reflected interference spectrum of the fiber FBG for transmission to a fiber optic sensing analyzer. The optical fiber sensor is arranged on the surface of the heating table to change the temperature or the ambient pressure of the heating table or arranged in the vacuum box to change the ambient pressure of the heating table, so that temperature or pressure sensing tests are carried out.
The reflectance spectrum in the experiment is shown in FIG. 8. When the external temperature or air pressure changes, the spectral line of the reflection spectrum can drift, and the corresponding wavelength values of a certain characteristic peak at different temperatures or air pressures are recorded, so that the high-precision measurement of the double parameters can be realized.
The invention has the beneficial effects that: the femtosecond laser direct-writing FBG manufactured by the technical method provided by the invention is combined with the temperature and air pressure test method of the optical fiber microsphere, and the all-fiber structure is adopted, so that the influence of electromagnetic interference on the detection result can be avoided. FBG that uses femto second laser preparation can be high temperature resistant, and the optic fibre microballon structure that uses chemical corrosion to combine the arc discharge preparation can realize atmospheric pressure sensing, therefore this structure can expand sensing parameter, realizes the measurement of temperature and atmospheric pressure simultaneously. The sensor has high reliability, and when the sensor is used, the part where the sensor is located is only required to be placed in an environment to be measured, and the other end of the sensor is connected with the spectrometer to complete real-time double-parameter measurement of a test system.
Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.
Claims (7)
1. A femtosecond laser direct writing FBG combined optical fiber microsphere preparation method is characterized by comprising the following steps:
(a) the femtosecond laser is used for preparing a Bragg fiber grating,
step a1, placing the SMF-28E optical fiber on a three-dimensional mobile platform to ensure clear visual field; step a2, focusing femtosecond laser spots on a fiber core of the SMF-28E fiber, and preparing a Bragg fiber grating in the fiber core area by adopting a direct writing mode;
(b) chemical corrosion is combined with arc discharge to prepare an optical fiber microsphere structure,
b1, removing a coating layer from the end face of the single-mode optical fiber, wiping the end face with alcohol, cutting the end face flat, and placing the end face in a hydrofluoric acid solution for end face corrosion; b2, placing the corroded optical fiber and the ordinary flat-cut optical fiber into a fusion splicer, and changing the discharge amount and the discharge time by adopting a fiber core alignment mode to finish the preparation of the optical fiber microsphere structure;
(c) preparing a fiber FBG bonding microsphere structure,
and (3) cascading the femtosecond laser direct writing Bragg fiber grating and the optical fiber microsphere structure through high-temperature arc discharge of a welding machine to prepare the optical fiber sensor.
2. The method according to claim 1, wherein the hydrofluoric acid solution has a concentration of 5% to 40%.
3. A temperature test method for bonding FBG (fiber Bragg Grating) with optical fiber microspheres by femtosecond laser direct writing is characterized by comprising the following steps of:
301, placing an optical fiber sensor on the surface of a heating table, wherein the optical fiber sensor is connected with a light source and an optical fiber sensing analyzer through an optical fiber circulator;
step 302, changing the temperature of the heating table, performing temperature sensing test on the optical fiber sensor, and transmitting the reflection interference spectrum of the FBG to the optical fiber sensing analyzer by using the optical fiber circulator to form a reflection spectrum spectral line.
4. A femtosecond laser direct writing FBG (fiber Bragg Grating) combined optical fiber microsphere air pressure testing method is characterized by comprising the following steps:
step 401, placing an optical fiber sensor in a vacuum box, wherein the optical fiber sensor is connected with a light source and an optical fiber sensing analyzer through an optical fiber circulator;
step 402, changing the ambient air pressure in the vacuum box, performing air pressure sensing test on the optical fiber sensor, and transmitting the reflection interference spectrum of the optical fiber FBG to the optical fiber sensing analyzer through the optical fiber circulator to form a reflection spectrum spectral line.
5. The test method as claimed in claim 3 or 4, wherein the light source is ASE light source with a wavelength range of 1520 and 1610 nm.
6. The method of claim 3, wherein the reflectance spectrum line shifts when the ambient temperature changes.
7. The method of claim 4, wherein the reflected spectrum shifts when the ambient pressure changes.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113406016A (en) * | 2021-06-15 | 2021-09-17 | 江西师范大学 | FBG-based monitoring device and monitoring method for gas quality of pressure steam sterilizer |
| CN114018432A (en) * | 2021-09-29 | 2022-02-08 | 南京大学 | All-fiber end face integrated minimum temperature hydraulic sensor and construction method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108168585A (en) * | 2017-12-22 | 2018-06-15 | 北京信息科技大学 | The method that fibre optical sensor is prepared based on chemical attack and welding electric discharge |
| CN108279029A (en) * | 2017-12-29 | 2018-07-13 | 北京信息科技大学 | Two-parameter fibre optical sensor and preparation method thereof based on LPFG and FBG cascade structures |
| CN109682778A (en) * | 2019-01-16 | 2019-04-26 | 北京信息科技大学 | Femtosecond laser prepares fiber core mismatch type FBG temperature refraction rate measurement method |
-
2020
- 2020-12-07 CN CN202011431494.0A patent/CN112729600A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108168585A (en) * | 2017-12-22 | 2018-06-15 | 北京信息科技大学 | The method that fibre optical sensor is prepared based on chemical attack and welding electric discharge |
| CN108279029A (en) * | 2017-12-29 | 2018-07-13 | 北京信息科技大学 | Two-parameter fibre optical sensor and preparation method thereof based on LPFG and FBG cascade structures |
| CN109682778A (en) * | 2019-01-16 | 2019-04-26 | 北京信息科技大学 | Femtosecond laser prepares fiber core mismatch type FBG temperature refraction rate measurement method |
Non-Patent Citations (3)
| Title |
|---|
| SHENGNAN WU 等: "FBG Incorporated Side-Open Fabry–Perot Cavity for Simultaneous Gas Pressure and Temperature Measurements", 《JOURNAL OF LIGHTWAVE TECHNOLOGY》 * |
| 刘申等: "光纤气泡微腔传感技术", 《应用科学学报》 * |
| 赵春柳等: "光纤微腔法布里-珀罗干涉传感器研究进展", 《应用科学学报》 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113406016A (en) * | 2021-06-15 | 2021-09-17 | 江西师范大学 | FBG-based monitoring device and monitoring method for gas quality of pressure steam sterilizer |
| CN113406016B (en) * | 2021-06-15 | 2022-11-04 | 江西师范大学 | FBG-based monitoring device and monitoring method for gas quality of pressure steam sterilizer |
| CN114018432A (en) * | 2021-09-29 | 2022-02-08 | 南京大学 | All-fiber end face integrated minimum temperature hydraulic sensor and construction method thereof |
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Application publication date: 20210430 |