CN113758507A - Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber - Google Patents

Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber Download PDF

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Publication number
CN113758507A
CN113758507A CN202011130793.0A CN202011130793A CN113758507A CN 113758507 A CN113758507 A CN 113758507A CN 202011130793 A CN202011130793 A CN 202011130793A CN 113758507 A CN113758507 A CN 113758507A
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fiber
mode
few
optical fiber
photonic crystal
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高学凯
宁提纲
裴丽
郑晶晶
李晶
王建帅
王春灿
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Beijing Jiaotong University
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Beijing Jiaotong University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/3537—Optical fibre sensor using a particular arrangement of the optical fibre itself
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D21/00—Measuring or testing not otherwise provided for
    • G01D21/02—Measuring two or more variables by means not covered by a single other subclass
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/3537—Optical fibre sensor using a particular arrangement of the optical fibre itself
    • G01D5/35374—Particular layout of the fiber
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
    • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
    • G01D5/26—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light
    • G01D5/32—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light
    • G01D5/34—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells
    • G01D5/353—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable characterised by optical transfer means, i.e. using infrared, visible, or ultraviolet light with attenuation or whole or partial obturation of beams of light the beams of light being detected by photocells influencing the transmission properties of an optical fibre
    • G01D5/3537—Optical fibre sensor using a particular arrangement of the optical fibre itself
    • G01D5/3538—Optical fibre sensor using a particular arrangement of the optical fibre itself using a particular type of fiber, e.g. fibre with several cores, PANDA fiber, fiber with an elliptic core or the like

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)

Abstract

The invention discloses a temperature and stress sensor based on a few-mode fiber and a photonic crystal fiber, which is suitable for the field of fiber sensing. The used optical fiber comprises an incident single-mode optical fiber (1), a few-mode optical fiber (2), a photonic crystal optical fiber (3), a few-mode optical fiber (4) and an emergent single-mode optical fiber (5). The other end of the few-mode fiber (2) is connected to the photonic crystal fiber (3) by a certain offset (6) by adopting an eccentric welding method, and the other end of the photonic crystal fiber (3) is connected to the few-mode fiber (4) by a certain offset (7) by adopting an eccentric welding method. Light enters the photonic crystal fiber (3) through the incident single-mode fiber (1) and the few-mode fiber (2), a plurality of cladding modes are excited, when the light enters the few-mode fiber (4), a Mach-Zehnder interferometer is formed, phase differences are generated due to different transmission paths of the modes to form interference, and the interference among the modes is enhanced through eccentric fusion, so that high sensitivity is realized. The sensor has the characteristics of simple manufacture, high sensitivity, electromagnetic interference resistance, stable performance and the like.

Description

Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber
Technical Field
The invention relates to a temperature and stress sensor based on a few-mode fiber and a photonic crystal fiber, which is suitable for the fields of fiber sensing technology and the like.
Background
According to the requirements of the transportation department on a plurality of opinions about further strengthening the quality of tunnel engineering and safety supervision work, an electronic access control attendance system, a personnel positioning management system, a toxic and harmful gas continuous monitoring management system, a video monitoring system, a safety step pitch monitoring system, a surrounding rock and supporting structure monitoring and measuring system and an advance forecasting system are required to be configured for tunnel construction, so that the informatization of tunnel construction safety management is promoted. A series of potential safety hazards during tunnel construction, the tunnel rock mass is one of common potential hazards when cracks appear, and if the cracks are not continuously monitored, serious safety accidents can be caused, and the life and property safety of constructors is harmed. The tunnel rock body cracks can damage the safety of the tunnel after exceeding the allowable crack width. The monitoring method for the cracks comprises a direct observation method, an electric micro-displacement sensor and the like, wherein the direct observation method cannot accurately monitor the cracks, and the electric micro-displacement sensor is easy to be interfered by electromagnetism and brings disadvantages to the monitoring of the cracks. The optical fiber sensor with higher sensitivity can better meet the actual requirement. High sensitivity is one of the main targets pursued by the optical fiber sensing technology, and is also one of the important indexes in practical application.
CN200920202121.9 proposes a HiBi-PCF-FLM stress sensor based on intensity detection, which uses a coupler and a polarization controller, and needs to adjust a polarizer before measurement, so that the use is inconvenient. CN201320268652.4 proposes a stress sensor based on photonic crystal fiber mode interference, which is simple in structure but not high in sensitivity. CN201810357584.6 proposes a temperature compensated photonic crystal fiber transverse stress sensor, which has a complex structure and poor repeatability. CN201610837857.8 an optic fibre stress sensing device, including the first single mode fiber, few mode fiber and the second single mode fiber that connect gradually, this structure is too simple, can't realize the stress measurement of high sensitivity. CN201310692913.X discloses a sapphire fiber grating temperature and stress sensor with a U-shaped structure, which is complex to manufacture and high in cost. CN201810889077.7 discloses a high-precision stress sensor based on fiber bragg grating, which is too complex in structure.
Disclosure of Invention
The invention aims to provide a temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber, which has the advantages of simple manufacture, high sensitivity, electromagnetic interference resistance, compact structure and stable performance.
The technical scheme of the invention is as follows:
a temperature and stress sensor based on a few-mode fiber and a photonic crystal fiber is provided, and the used fibers comprise a single-mode fiber, a few-mode fiber and a photonic crystal fiber. The composite structure of the single-mode fiber, the few-mode fiber, the photonic crystal fiber, the few-mode fiber and the single-mode fiber is obtained by welding different fibers, and two ends of the photonic crystal fiber are respectively connected with two sections of the few-mode fibers with certain offset.
The invention has the beneficial effects that: the invention provides a temperature and stress sensor based on a few-mode fiber and a photonic crystal fiber, which can be used for welding the photonic crystal fiber and the few-mode fiber only by adopting an eccentric welding method, and can simultaneously realize stress measurement by measuring the offset of a loss peak of a transmission spectrum, thereby realizing measurement of the size change of a crack. The structure has the characteristics of simple manufacture, high sensitivity, electromagnetic interference resistance, compact structure, stable performance and the like.
Drawings
FIG. 1 is a schematic structural diagram of the present invention.
Drawing reference numbers: 1-incident single mode fiber, 2-few mode fiber, 3-photonic crystal fiber, 4-few mode fiber, 5-emergent single mode fiber, 6-offset and 7-offset.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
In the first embodiment, an incident single mode fiber 1 is connected to one end of a few-mode fiber 2, the other end of the few-mode fiber 2 is connected to a photonic crystal fiber 3 by an eccentric fusion method, and the offset 6 is h1,h10 μm, connecting the other end of the photonic crystal fiber 3 with the few-mode fiber 4 by eccentric fusion, wherein the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 0 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; two sections of the used few-mode optical fiber are two-mode few-mode optical fibers; the photonic crystal fiber is refractive index guiding type photonic crystal fiber.
In the second embodiment, the incident single-mode fiber 1 is connected to one end of the few-mode fiber 2, the other end of the few-mode fiber 2 is connected to the photonic crystal fiber 3 by eccentric fusion, and the offset 6 is h1,h1Is in the range of 0 μm, the other end of the photonic crystal fiber 3 is connected with the few-mode fiber 4 by eccentric fusion, and the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 10 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; two sections of the used few-mode optical fiber are two-mode few-mode optical fibers; the photonic crystal fiber is a photonic band gap type photonic crystal fiber.
In the third embodiment, the incident single-mode fiber 1 is connected to one end of the few-mode fiber 2, the other end of the few-mode fiber 2 is connected to the photonic crystal fiber 3 by eccentric fusion, and the offset 6 is h1,h1Is 20 μm, and the other end of the photonic crystal fiber 3 is connected with the few-mode fiber 4 by eccentric fusion, wherein the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 20 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; two sections of the used few-mode optical fiber are four-mode few-mode optical fibers; the photonic crystal fiber is refractive index guiding type photonic crystal fiber.
In the fourth embodiment, the incident single-mode fiber 1 is connected to one end of the few-mode fiber 2, the other end of the few-mode fiber 2 is connected to the photonic crystal fiber 3 by eccentric fusion, and the offset 6 is h1,h1Is 10 μm, and the other end of the photonic crystal fiber 3 is connected with the few-mode fiber 4 by eccentric fusion, wherein the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 20 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; two sections of the used few-mode optical fiber are four-mode few-mode optical fibers; the photonic crystal fiber is a photonic band gap type photonic crystal fiber.
In the fifth embodiment, the incident single-mode fiber 1 is connected to one end of the few-mode fiber 2, the other end of the few-mode fiber 2 is connected to the photonic crystal fiber 3 by eccentric fusion, and the offset 6 is h1,h1Is in the range of 0 μm, the other end of the photonic crystal fiber 3 is connected with the few-mode fiber 4 by eccentric fusion, and the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 50 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; the two sections of the used few-mode optical fiber are a two-mode few-mode optical fiber and a four-mode few-mode optical fiber respectively; the photonic crystal fiber is refractive index guiding type photonic crystal fiber.
In the sixth embodiment, the incident single-mode fiber 1 is connected to one end of the few-mode fiber 2, the other end of the few-mode fiber 2 is connected to the photonic crystal fiber 3 by eccentric fusion, and the offset 6 is h1,h1Is 20 μm, and the other end of the photonic crystal fiber 3 is connected with the few-mode fiber 4 by eccentric fusion, wherein the offset 7 is h2,h2The range of the few-mode optical fiber 4 is 50 mu m, and the few-mode optical fiber 4 is connected with an emergent single-mode optical fiber 5; the two sections of the used few-mode optical fiber are a two-mode few-mode optical fiber and a four-mode few-mode optical fiber respectively; the photonic crystal fiber is a photonic band gap type photonic crystal fiber.

Claims (2)

1. A temperature and stress sensor based on few-mode fiber and photonic crystal fiber is characterized in that: the used optical fiber comprises an incident single-mode optical fiber (1), a few-mode optical fiber (2), a photonic crystal optical fiber (3), a few-mode optical fiber (4) and an emergent single-mode optical fiber (5), and the specific connection mode is as follows: the incident single-mode fiber (1) is connected with one end of the few-mode fiber (2), the other end of the few-mode fiber (2) is connected with the photonic crystal fiber (3) by adopting an eccentric welding method, the other end of the photonic crystal fiber (3) is connected with the few-mode fiber (4) by adopting an eccentric welding method, and the few-mode fiber (4) is connected with the emergent single-mode fiber (5).
2. The few-mode fiber and photonic crystal fiber based temperature and stress sensor of claim 1, wherein: the used few-mode optical fiber is not limited to two-mode few-mode optical fiber, four-mode few-mode optical fiber and the like; the photonic crystal fiber used is not limited to refractive index guiding type photonic crystal fiber, photonic band gap type photonic crystal fiber, or the like.
CN202011130793.0A 2020-10-21 2020-10-21 Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber Pending CN113758507A (en)

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CN205790916U (en) * 2016-05-31 2016-12-07 中国工程物理研究院激光聚变研究中心 Super continuous spectrums laser generator
CN106404216A (en) * 2016-10-28 2017-02-15 燕山大学 Refractive index insensitive cascade type single-mode-less-mode-single-mode fiber temperature sensor
CN107270949A (en) * 2017-06-22 2017-10-20 武汉理工大学 Temperature and strain dual sampling system and its measuring method
CN108195493A (en) * 2018-01-31 2018-06-22 中国计量大学 One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device
EP3384248A1 (en) * 2015-12-02 2018-10-10 Danmarks Tekniske Universitet Optical measuring system with an interrogator and a polymer-based single-mode fibre optic sensor system
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Publication number Priority date Publication date Assignee Title
CN104297208A (en) * 2014-10-21 2015-01-21 天津理工大学 Interferometric optical fiber sensor based on pohotonic crystal optical fiber
EP3384248A1 (en) * 2015-12-02 2018-10-10 Danmarks Tekniske Universitet Optical measuring system with an interrogator and a polymer-based single-mode fibre optic sensor system
CN205790916U (en) * 2016-05-31 2016-12-07 中国工程物理研究院激光聚变研究中心 Super continuous spectrums laser generator
CN106404216A (en) * 2016-10-28 2017-02-15 燕山大学 Refractive index insensitive cascade type single-mode-less-mode-single-mode fiber temperature sensor
CN107270949A (en) * 2017-06-22 2017-10-20 武汉理工大学 Temperature and strain dual sampling system and its measuring method
CN108195493A (en) * 2018-01-31 2018-06-22 中国计量大学 One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device
CN209689810U (en) * 2019-02-22 2019-11-26 中国计量大学 A kind of Mach-Zehnder interferometer type baroceptor based on photonic crystal fiber

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Application publication date: 20211207