CN110207846B - Capillary tube optical fiber temperature sensor - Google Patents
Capillary tube optical fiber temperature sensor Download PDFInfo
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- CN110207846B CN110207846B CN201910560318.8A CN201910560318A CN110207846B CN 110207846 B CN110207846 B CN 110207846B CN 201910560318 A CN201910560318 A CN 201910560318A CN 110207846 B CN110207846 B CN 110207846B
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- 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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Abstract
The invention relates to a capillary tube optical fiber temperature sensor, and belongs to the field of optical fiber temperature sensing. The device comprises a light source, a tail fiber, a fiber circulator, a capillary fiber, liquid, a glass bulb and a light detector; the light source is connected with one end of the optical fiber circulator through the tail fiber, the optical detector is connected with the other end of the optical fiber circulator through the tail fiber, the other end of the optical fiber circulator is connected with one end of the capillary optical fiber through the tail fiber, the other end of the capillary optical fiber is connected with the glass bulb and is integrally sealed, and liquid is placed in the capillary optical fiber and the glass bulb. The capillary optical fiber is a suspended core hollow optical fiber or an inner wall annular waveguide hollow optical fiber; the length of liquid in the capillary optical fiber air hole is L; the end part of the fiber core at the end where the capillary fiber is connected with the glass bubble is plated with a metal film to change the reflectivity of the end part, and the reflectivity value range is 90-100%. The optical fiber temperature sensor has the advantages of small volume, corrosion resistance, easiness in preparation, low cost, simple structure, difficulty in electromagnetic interference, large temperature range, high sensitivity and the like.
Description
Technical Field
The invention relates to a capillary tube optical fiber temperature sensor, and belongs to the field of optical fiber temperature sensing.
Background
Compared with the traditional sensor, the optical fiber sensor has the characteristics of large information capacity, electromagnetic interference resistance, corrosion resistance, simple structure, small volume and the like. The application range of the optical fiber sensor has penetrated into various fields of national defense and military, civil engineering, energy environmental protection, medical health and the like, can realize measurement of a plurality of physical quantities such as temperature, stress, vibration, electromagnetic field and the like, and can be used in the environment which cannot be adapted to the conventional electronic temperature sensor.
The current optical fiber sensors applied to temperature testing mainly include fiber grating sensors, photonic crystal fiber sensors, and dislocation structure fiber sensors, but these sensors need to consider many factors in practical applications, such as: the sensor has the problems of high manufacturing cost, short service life, low sensitivity and the like.
Application publication No. CN109029777A proposes an optical fiber thermometer based on the principle of interference, which includes a light source, a coupler, a container, a liquid and a light detector; the optical signal generated by the light source is transmitted to the tail fiber through the tail fiber and the coupler, and at the end part of the tail fiber, a part of the optical signal is reflected and transmitted to the optical detector through the coupler and the tail fiber; and the other part of the optical signal is transmitted to the upper surface of the liquid through the end part of the tail fiber, reflected back to the tail fiber and transmitted to the optical detector through the coupler and the tail fiber. The optical signal received by the optical detector contains the related information of the distance between the tail end of the tail fiber and the upper surface of the liquid, and the distance is influenced by the temperature, so that the optical sensing of the temperature is realized.
However, the optical fiber thermometer has large volume and low integration level, and is inconvenient to use because the optical fiber thermometer must be placed upright.
Disclosure of Invention
The invention aims to provide a capillary tube optical fiber temperature sensor for solving the problems of large volume and low integration level of an optical fiber thermometer.
The purpose of the invention is realized as follows: a capillary fiber temperature sensor comprises a light source, a tail fiber, a fiber circulator, a capillary fiber, liquid, a glass bulb and a light detector; the optical fiber circulator is provided with three ports, a light source is connected with one end of the optical fiber circulator through a tail fiber, an optical detector is connected with the other end of the optical fiber circulator through the tail fiber, the other end of the optical fiber circulator is connected with one end of a capillary optical fiber through the tail fiber, the other end of the capillary optical fiber is connected with a glass bulb and is integrally sealed, and liquid is placed in the capillary optical fiber and the glass bulb.
The invention also includes such structural features:
the capillary optical fiber is manufactured by drawing a prefabricated rod.
The end part of the fiber core at the end where the capillary optical fiber is connected with the glass bulb is plated with a metal film for changing the reflectivity of the end part, and the reflectivity value range is 90-100%.
The capillary optical fiber is a suspended core hollow optical fiber or an inner wall annular waveguide hollow optical fiber.
The liquid is filled into the capillary optical fiber air hole through the glass bubble, the liquid is highlight absorption liquid, the length of the liquid is L, and L is a positive number.
The liquid is mercury.
Compared with the prior art, the invention has the beneficial effects that: the optical fiber temperature sensor has small volume and high integration level, and the optical fiber used by the optical fiber temperature sensor is a capillary optical fiber which is easy to prepare, simple in structure, low in cost, large in temperature measurement range and high in sensitivity compared with other optical fibers such as photonic crystal optical fiber and the like.
Drawings
FIG. 1 is a schematic diagram of the optical path and structure of a capillary fiber optic temperature sensor;
FIG. 2 is a schematic cross-sectional structure of a suspended single core hollow optic fiber;
FIG. 3 is a schematic diagram of a cross-sectional structure of a suspended multi-core hollow optic fiber;
fig. 4 is a schematic cross-sectional structure diagram of an inner wall ring waveguide hollow optical fiber.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The invention provides a capillary optical fiber temperature sensor which integrates a temperature sensor into a capillary optical fiber, has small volume and high integration level. The capillary optical fiber can be manufactured by drawing a prefabricated rod, and has simple preparation and low cost.
The invention provides a capillary optical fiber temperature sensor which is characterized by comprising a light source 1, an optical fiber circulator 2, a capillary optical fiber 4, liquid 6, a glass bubble 5 and a light detector 3; the light source is connected with the optical fiber circulator through a tail fiber 11, the optical detector is connected with the optical fiber circulator through a tail fiber 12, the optical fiber circulator is connected with a capillary optical fiber through a tail fiber 13, the other end of the capillary optical fiber is connected with a glass bulb and is integrally sealed, and liquid is placed in the capillary optical fiber and the glass bulb.
Light generated by the light source is transmitted to the capillary fiber through the tail fiber 11, the fiber circulator and the tail fiber 13, and is reflected at the end part of the capillary fiber connected with the glass bubble due to the fact that the end part of the fiber core at the end part of the capillary fiber connected with the glass bubble is plated with a metal film, and then is transmitted to the optical detector through the capillary fiber, the tail fiber 13, the fiber circulator and the tail fiber 12. The capillary optical fiber of the present invention includes a suspended core hollow optical fiber and an inner wall annular waveguide hollow optical fiber. The number of the suspended core hollow optical fiber cores is one or more. The hollow part of the capillary optical fiber can be filled with liquid to act with the optical fiber waveguide core, and a closed space is provided for the interaction of the fiber core and the liquid.
The invention fills high light absorption liquid into the air hole of the capillary optical fiber through the glass bubble, wherein the liquid length is L, and L is a positive number. The liquid in the glass bubble is influenced by the environmental temperature, the action length of the fiber core and the liquid in the capillary optical fiber can be changed, and the absorption loss of the capillary optical fiber is linearly changed along with the change of the action length of the fiber core and the liquid in the capillary optical fiber, so that the absorption loss of the capillary optical fiber is linearly changed along with the change of the environmental temperature, and the light intensity measured by the optical detector is also linearly changed along with the change of the environmental temperature. The optical signal is transmitted back and forth once in the fiber core of the capillary optical fiber, so that the error can be effectively reduced.
As a further improvement of the invention, the end part of the fiber core at the end where the capillary optical fiber is connected with the glass bubble is plated with a metal film to change the reflectivity of the end part, and the reflectivity ranges from 90% to 100%.
As a further improvement of the present invention, the liquid is mercury, but the liquid is not limited to liquid metal, and a liquid having high light absorption may be used.
Two embodiments of the invention are given below with reference to the accompanying drawings.
Example 1:
with reference to fig. 1, 2, and 3, the capillary fiber is a suspended core hollow fiber.
Fig. 2 and 3 are schematic cross-sectional structures of suspended core hollow optical fibers, the central axes of the air holes are coincident with the central circumference of the optical fiber, and the fiber cores of the suspended core hollow optical fibers are one or more. Wherein FIG. 2 is a schematic diagram of a cross-sectional structure of a suspended single core hollow optic fiber: 1 is the core of the hollow optical fiber with a suspended core; 2, the hollow optical fiber substrate with the suspended core is quartz or glass with lower refractive index; and 3 is an air hole for suspending the core hollow optical fiber. FIG. 3 is a schematic diagram of a cross-sectional structure of a suspended multi-core hollow fiber: 1. 4 is the core of the hollow optical fiber with a suspended core; 2, the hollow optical fiber substrate with the suspended core is quartz or glass with lower refractive index; and 3 is an air hole for suspending the core hollow optical fiber. When the optical signal propagates in the hollow optical fiber with the suspended core, the optical signal mainly propagates in the fiber core. The capillary optical fiber temperature sensor is placed in a controllable temperature field, the temperature is changed, a series of light intensity values measured by the optical detector at the known temperature can be obtained, mathematical analysis is applied, the function relation corresponding to the specific light intensity value and the temperature is obtained, and the calibration of the sensor is completed. And (3) placing the calibrated capillary optical fiber temperature sensor in a temperature field to be measured, and obtaining the temperature of the temperature field to be measured according to the measured functional relation.
Example 2:
referring to fig. 1 and 4, the capillary fiber is an inner wall ring waveguide hollow fiber.
FIG. 4 is a schematic cross-sectional view of a hollow optical fiber having an inner wall annular waveguide, a capillary optical fiber having an annular waveguide layer, 1 is a high purity quartz substrate tube, 2 is an optical waveguide layer inside the high purity quartz substrate tube, 3 is an air hole in the center, the optical waveguide layer is deposited on the surface of the high purity quartz substrate tube, the refractive index of the waveguide layer is greater than that of the high purity quartz substrate tube, the waveguide layer is made of a transparent synthetic quartz material doped with Ge ions, and the guided light propagates through the waveguide layer. The capillary optical fiber temperature sensor is placed in a controllable temperature field, the temperature is changed, a series of light intensity values measured by the optical detector at the known temperature can be obtained, mathematical analysis is applied, the function relation corresponding to the specific light intensity value and the temperature is obtained, and the calibration of the sensor is completed. And (3) placing the calibrated capillary optical fiber temperature sensor in a temperature field to be measured, and obtaining the temperature of the temperature field to be measured according to the measured functional relation.
In summary, the present invention provides a capillary optical fiber temperature sensor, as shown in fig. 1, which is a schematic diagram of an optical path and a schematic diagram of a structure of the capillary optical fiber temperature sensor; comprises a light source 1, a fiber optic circulator 2, a light detector 3, a capillary fiber 4, a glass bubble 5 and a liquid 6. The light source is connected with the optical fiber circulator through the tail fiber 11, the optical detector is connected with the optical fiber circulator through the tail fiber 12, the optical fiber circulator is connected with the capillary optical fiber through the tail fiber 13, the other end of the capillary optical fiber is connected with the glass bulb and is integrally sealed, and the liquid is placed in the glass bulb and the capillary optical fiber. The capillary optical fiber is a suspended core hollow optical fiber or an inner wall annular waveguide hollow optical fiber; the length of liquid in the capillary optical fiber air hole is L, and L is a positive number; the end part of the fiber core at the end where the capillary fiber is connected with the glass bubble is plated with a metal film to change the reflectivity of the end part, and the reflectivity value range is 90-100%. The optical fiber temperature sensor has the characteristics of small volume, corrosion resistance, easiness in preparation, low cost, simple structure, difficulty in electromagnetic interference, large temperature range, high sensitivity and the like.
Claims (3)
1. A capillary fiber temperature sensor comprises a light source, a tail fiber, a fiber circulator, a capillary fiber, liquid, a glass bulb and a light detector; the method is characterized in that: the liquid is high light absorption liquid, and the liquid is influenced by the ambient temperature, and can change the acting length of fiber core and liquid in the capillary optical fiber, the said capillary optical fiber is hollow optical fiber of hanging core or hollow optical fiber of annular waveguide of inner wall, the optical fiber circulator has three ports, the light source couples to one end of the optical fiber circulator through the tail fiber, the photodetector couples to another end of the optical fiber circulator through the tail fiber, another end of the optical fiber circulator couples to one end of the capillary optical fiber through the tail fiber, another end of the capillary optical fiber couples to glass bubble and seals integrally, the liquid is put into capillary optical fiber and glass bubble; light generated by the light source is transmitted into the capillary optical fiber through the tail fiber, the optical fiber circulator and the tail fiber, the end part of the fiber core at the end where the capillary optical fiber is connected with the glass bubble is plated with a metal film for changing the reflectivity of the end part, the light is reflected at the end part at the end where the capillary optical fiber is connected with the glass bubble, and the light is transmitted to the optical detector through the capillary optical fiber, the tail fiber, the optical fiber circulator and the tail fiber again.
2. The capillary optic fiber temperature sensor of claim 1, wherein: the capillary optical fiber is manufactured by drawing a prefabricated rod.
3. The capillary optic fiber temperature sensor according to claim 1 or 2, wherein: the reflectivity of the metal film ranges from 90% to 100%.
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| CN201910560318.8A CN110207846B (en) | 2019-06-26 | 2019-06-26 | Capillary tube optical fiber temperature sensor |
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| CN201910560318.8A CN110207846B (en) | 2019-06-26 | 2019-06-26 | Capillary tube optical fiber temperature sensor |
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| CN110207846B true CN110207846B (en) | 2021-02-02 |
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| CN111457950B (en) * | 2020-03-11 | 2021-08-20 | 复旦大学 | Fabry-Perot resonant cavity optical microbubble sensor and preparation method thereof |
| CN112326060A (en) * | 2020-12-03 | 2021-02-05 | 南京信息工程大学 | High-sensitivity parallel double-F-P cavity optical fiber temperature sensing device |
| CN113707518B (en) * | 2021-08-20 | 2024-08-16 | 中国科学院电工研究所 | X-ray target |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030002218A (en) * | 2001-06-30 | 2003-01-08 | 학교법인 성균관대학 | Optical fiber thermometer |
| CN102288326A (en) * | 2011-07-07 | 2011-12-21 | 天津大学 | Method and sensor for measuring temperature of photonic crystal fiber (PCF) filled with mixed solution |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1023730C (en) * | 1990-09-30 | 1994-02-09 | 吉林大学 | Liquid-core optical fiber sensor with changeable length of light transmission |
| CN1017928B (en) * | 1991-02-05 | 1992-08-19 | 田果成 | Mercury temperature sensor with optical fiber |
| CN202041222U (en) * | 2011-03-29 | 2011-11-16 | 哈尔滨工程大学 | In-wall waveguide long-period fiber grating sensor |
| KR101314848B1 (en) * | 2012-07-17 | 2013-10-04 | 파워옵틱스(주) | Apparatus of measuring temperature and refractive index using double core fiber bragg grating |
| CN205656129U (en) * | 2016-03-08 | 2016-10-19 | 中国计量学院 | Optic fibre hydrogen sensor based on bistrichiasis tubule |
| CN106017724B (en) * | 2016-05-05 | 2019-01-22 | 北京交通大学 | A kind of D type hollow doubly clad optical fiber SPR temperature sensor of liquid filling |
| CN107860492B (en) * | 2017-11-06 | 2020-08-07 | 北京科技大学 | Photonic crystal fiber temperature sensor based on SPR |
| CN109932078A (en) * | 2019-03-27 | 2019-06-25 | 哈尔滨工业大学（威海） | A kind of highly sensitive optical fiber sensing probe and preparation method thereof |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20030002218A (en) * | 2001-06-30 | 2003-01-08 | 학교법인 성균관대학 | Optical fiber thermometer |
| CN102288326A (en) * | 2011-07-07 | 2011-12-21 | 天津大学 | Method and sensor for measuring temperature of photonic crystal fiber (PCF) filled with mixed solution |
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