CN108195493A - One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device - Google Patents
One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device Download PDFInfo
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- CN108195493A CN108195493A CN201810094081.4A CN201810094081A CN108195493A CN 108195493 A CN108195493 A CN 108195493A CN 201810094081 A CN201810094081 A CN 201810094081A CN 108195493 A CN108195493 A CN 108195493A
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- 239000000835 fiber Substances 0.000 claims abstract description 63
- 239000013307 optical fiber Substances 0.000 claims abstract description 29
- 239000004038 photonic crystal Substances 0.000 claims abstract description 21
- 230000035945 sensitivity Effects 0.000 claims abstract description 15
- 230000000694 effects Effects 0.000 claims abstract description 7
- 238000003466 welding Methods 0.000 claims abstract description 7
- 230000003287 optical effect Effects 0.000 claims description 8
- 230000008859 change Effects 0.000 claims description 7
- 238000005253 cladding Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 3
- 238000010183 spectrum analysis Methods 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 238000005259 measurement Methods 0.000 abstract description 8
- 238000001228 spectrum Methods 0.000 abstract description 4
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000012360 testing method Methods 0.000 abstract description 3
- 238000011160 research Methods 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 230000003595 spectral effect Effects 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 230000001953 sensory effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
- G01L1/242—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet the material being an optical fibre
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
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Abstract
The present invention provides one kind to be based on photonic crystal fiber（PCF）Mach Zehnder interferometer（MZI）Highly sensitive stress sensing device, including wideband light source, senser element and spectroanalysis instrument.Wherein senser element is by the first single mode optical fiber, graded index multimode fiber, PCF and the welding successively of the second single mode optical fiber, it is characterized in that the weld of PCF and other optical fiber has collapsing for certain length.One end of sensing is connected with wideband light source, other end access spectrometer, and light, which enters to be collapsed during region is assembled into single mode optical fiber by second after graded index multimode fiber is expanded by region of collapsing into PCF again from single mode optical fiber, forms Mach Zehnder interferometer（MZI）, due to the self-focusing effect in graded index multimode fiber, can greatly improve the sensitivity of senser element.By the wavelength shift for measuring transmitted spectrum, you can calculate the numerical value of test environment parameter.The present invention have the advantages that it is compact-sized, be simple to manufacture, high sensitivity and wide range of measurement and Temperature cross-over sensitivity are low etc., be applicable in various environmental parameters measurement, especially stress measurement.
Description
Technical field
The present invention provides one kind to be based on photonic crystal fiber（PCF）Mach-Zehnder interferometer（MZI）High sensitivity
Stress sensing device belongs to technical field of optical fiber sensing.
Background technology
The world today is all completed the exploitation of information, acquisition, transmission and the processing overwhelming majority by sensor, and people
Requirement to sensor it is also higher and higher, it is desirable to sensor can be more sensitive, accurate, compact and intelligent, no matter what
Kind environment can keep high-performance.In numerous fibre optical sensors, based on Mach-Zehnder interferometer（MZI）The optical fiber of characteristic passes
Sensor rapidly develops, and becomes an important branch of fibre optical sensor research field.And stress test this aspect current
There are the production and control in demand, such as aerospace, enterprise's production, engineering manufacture field in many fields in the world, should
Power is all one of their important parameter.Fiber Mach-Zehnder interferometer type（MZI）Strain gauge is relative to traditional sensors
For have the characteristics that small, light-weight, fast response time, anti-electromagnetic interference capability are strong, corrosion-resistant.In recent years, optical fiber horse
Conspicuous-Zehnder interferometer type（MZI）Strain gauge is not only in many colleges and universities as the object of scientific research, while in civil enterprise
All have in industry, military aspect and space flight and aviation engineering and be widely applied very much, the structure for making this type fiber sensor is more
Kind is various, so the scientific research for this aspect brings unlimited potentiality.
Sensing arrangement in the present invention applies PCF and graded index multimode fiber.PCF is special because of its unique optics
Property, structure can flexible design the advantages of and the variation of the material parameter to being filled in airport it is sensitive the characteristics of and as in recent years
Carry out the research hotspot of sensory field.PCF is as new sensed media, because along the air hole array of optical fiber genesis analysis, from
And low thermo-optical coeffecient is presented, this optical fiber mach-Ze De interference-types based on PCF（MZI）Strain gauge has sensitivity
Height, manufacturing technology is simple, it is compact-sized the advantages of.But the visibility of response spectra（Spectrum between peak value and its adjacent trough
Transmit difference）It is relatively low, and due to the limited disturbing effect between fibre core and cladding mode, 3-dB bandwidth usually compared with
It is wide.Usually we can be by obtaining the variation with analysis center's wavelength come measuring strain sensitivity.Graded-index multimode light
Fibre has self-focusing effect, by applying stress to sensing arrangement, can change the self-focusing of light in graded index multimode fiber
Length, so as to be had an impact to optical path difference, and improve the sensitivity of senser element.
Invention content
Present invention basis to the requirement of sensor, has made a kind of based on PCF Mach-Zehnder interferometers instantly（MZI）'s
Highly sensitive stress sensing device, it have it is compact-sized, be simple to manufacture, high sensitivity and wide range of measurement and Temperature cross-over
The advantages such as sensitivity is low are applicable in various environmental parameters and measure, especially stress measurement.
The technical solution adopted for solving the technical problem of the present invention is：One kind is based on PCF Mach-Zehnder interferometers（MZI）
Highly sensitive stress sensing device, including wideband light source, senser element and spectroanalysis instrument, connection mode is：Broadband light
Source, senser element and spectroanalysis instrument are sequentially connected；Its feature is shown as：The fiber optic sensing device told about is by the first single mode
What optical fiber, graded index multimode fiber, PCF and the second single mode optical fiber were connected in sequence, key is with connecting to PCF
Two end nodes connect have carried out electric discharge and have collapsed, and collapsed portions form the structure of similar coreless fiber, so as to form Mach-pool
Deccan interferometer（MZI）Fibre optical sensor；And graded index multimode fiber has self-focusing effect, by applying to sensing arrangement
Stress can change the self-focusing length of light in graded index multimode fiber, so as to be had an impact to optical path difference, and improve sensing
The sensitivity of device.
Material used in senser element is the single mode optical fiber of 125 μm of cladding diameter, and 62.5 μm or 50 μm of core diameter is gradually
Variable refractivity multimode fibre and LMA-10 type photonic crystal fibers, are formed by optical fiber splicer welding.
Preferably, the graded index fiber fiber lengths are 5~15cm.
Preferably, the length of the PCF is ＜ 5mm.
Preferably, the zone length of collapsing is 150~220 μm.
Compared with the prior art, the invention has the advantages that：
1st, the senser element made, the knot that is that cheap single mode optical fiber, graded index multimode fiber are combined with PCF
Structure is fairly simple, easy to make, and PCF length used is shorter, and cost of manufacture is than relatively low.
2nd, senser element all has sensibility to stress, pressure, refractive index, can be used for the measurement of various environmental parameters,
Especially to the reacting condition of stress sensitivity, there is very high stress sensitivity and wider measurement range.
3rd, for senser element to the susceptibility of temperature than relatively low, when measurement, can reduce influence of the environment temperature to sensor,
And temperature is higher than to the susceptibility of stress, so Temperature cross-over remolding sensitivity is relatively low.
Description of the drawings
In order to illustrate the embodiments of the present invention more clearly or technical solution, the present invention is made with reference to the accompanying drawings and examples
It further illustrates.
Fig. 1 practices system schematic for the present invention's.
Fig. 2 is inventive sensor part structure diagram.
In figure, 1. wideband light sources, 2. senser elements, 3. spectroanalysis instruments, 4. first single mode optical fibers, 5. graded indexs are more
Mode fiber, 6. photonic crystal fibers, 6a. photonic crystal fibers first are collapsed region, the second collapsed region of 6b. photonic crystal fibers
Domain, 6c. photonic crystal fibers are not collapsed region, 7. second single mode optical fibers.
Specific embodiment
Below in conjunction with the accompanying drawings and embodiment the invention will be further described：
Fig. 1 show the present invention practice system schematic,
Including wideband light source 1, senser element 2, spectroanalysis instrument 3.Its connection mode is：Wideband light source, senser element and spectrum
Analyzer is sequentially connected.
Fig. 2 show inventive sensor part structure diagram, and the senser element is by the first single mode optical fiber 4, gradual change folding
Rate multimode fibre 5 is penetrated, 6 and second single mode optical fiber 7 of photonic crystal fiber is formed, and is connected to this section of region of photonic crystal fiber 6
Include welding region 6a, the photonic crystal fiber second of collapsing of the photonic crystal fiber to be formed first that discharge to collapse region 6b and light
Photonic crystal fiber is not collapsed region 6c.Entire sensing arrangement is by 125 μm of single mode optical fibers of fibre cladding, 62.5 μm of gradual changes of core diameter
Index multimode fiber and LMA-10 types photonic crystal fiber composition.
The production method of the senser element is：By the gradual change of 4 one end of the first single mode optical fiber of random length and 12cm long
5 one end of index multimode fiber is welding together, and 5 other end of graded index multimode fiber is carried out with 2mm long photonic crystal fibers 6
Welding, adjusting discharge time of heat sealing machine carries out photonic crystal fiber 6 electric discharge and collapses, and the first region 6a length of collapsing is
206 μm, 7 welding of the other end of photonic crystal fiber 6 and the second single mode optical fiber carries out photonic crystal fiber using the same manner
Electric discharge is collapsed, and second collapses region 6b length for 208 μm.
With reference to Fig. 1 and 2, specific operation principle is introduced：First, the light in wideband light source enters gradual change by single mode optical fiber
Index multimode fiber, so as to increase the pattern of light field, then light is collapsed from multimode fibre 5 into photonic crystal fiber first
Region, this region of collapsing are equivalent to coreless fiber, and light is expanded in the first region of collapsing, and a part of light passes through from fibre core, separately
A part of light passes through from the covering of optical fiber, so as to form Mach-Zehnder interferometer（MZI）, light is laggard by photonic crystal fiber
Enter second to collapse region, assemble and enter in the second single mode optical fiber, formed in the spectral transmissions to spectrometer after interference, measure output
The wavelength shift at spectral signature peak, you can calculate the numerical value of test environment parameter.And graded index multimode fiber has
Self-focusing effect by applying stress to sensing arrangement, can change the self-focusing length of light in graded index multimode fiber, from
And optical path difference is had an impact, and improve the sensitivity of senser element.
Particular embodiments described above has carried out the purpose of the present invention, technical solution and advantageous effect further in detail
It describes in detail bright, it should be appreciated that, the above is only a specific embodiment of the present invention, is not intended to restrict the invention, all
Within the spirit and principles in the present invention, any modification, equivalent substitution, improvement and etc. done should be included in the guarantor of the present invention
Within the scope of shield.
Claims (5)
1. one kind is based on photonic crystal fiber（PCF）Mach-Zehnder interferometer（MZI）Highly sensitive stress sensing device,
It is characterized in that：Including wideband light source, senser element and spectroanalysis instrument, connection mode is：Wideband light source, senser element and light
Spectrum analysis instrument is sequentially connected；Its feature is shown as：The fiber optic sensing device told about is by the first single mode optical fiber, graded index
What multimode fibre, PCF and the second single mode optical fiber were connected in sequence, key be with to two end nodes that PCF is connect into
Electric discharge of having gone is collapsed, and collapsed portions form the structure of similar coreless fiber, so as to form Mach-Zehnder interferometer（MZI）
Fibre optical sensor；And graded index multimode fiber has self-focusing effect, by applying stress to sensing arrangement, can change gradually
The self-focusing length of light in variable refractivity multimode fibre, so as to be had an impact to optical path difference, and improve the sensitivity of senser element.
2. a kind of Mach-Zehnder interferometer based on PCF according to claim 1（MZI）Highly sensitive stress sensing dress
It puts, it is characterised in that：Material used in senser element is the single mode optical fiber of 125 μm of cladding diameter, 62.5 μm of core diameter or 50 μ
The graded index multimode fiber of m and LMA-10 type photonic crystal fibers, are formed by optical fiber splicer welding.
3. a kind of Mach-Zehnder interferometer based on PCF according to claim 2（MZI）Highly sensitive stress sensing dress
It puts, it is characterised in that：The graded index fiber fiber lengths are 5~15cm.
4. a kind of Mach-Zehnder interferometer based on PCF according to claim 2（MZI）Highly sensitive stress sensing dress
It puts, it is characterised in that：The length of the PCF is ＜ 5mm.
5. a kind of Mach-Zehnder interferometer based on PCF according to claim 2（MZI）Highly sensitive stress sensing dress
It puts, it is characterised in that：The zone length of collapsing is 150~220 μm.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810094081.4A CN108195493A (en) | 2018-01-31 | 2018-01-31 | One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device |
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| CN201810094081.4A CN108195493A (en) | 2018-01-31 | 2018-01-31 | One kind is based on PCF Mach-Zehnder interferometers（MZI）Highly sensitive stress sensing device |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109000809A (en) * | 2018-07-17 | 2018-12-14 | 南通大学 | A kind of Mach-Zender interferometer and its making apparatus and production method |
| CN110749572A (en) * | 2019-10-29 | 2020-02-04 | 广州特种承压设备检测研究院 | Novel graphene optical fiber gas sensor measuring system and method for measuring hydrogen sulfide gas by using same |
| CN111504529A (en) * | 2020-04-24 | 2020-08-07 | 南昌航空大学 | Micro-nano optical fiber nano Newton level mechanical sensor |
| CN113340456A (en) * | 2021-07-15 | 2021-09-03 | 中南大学 | Optical fiber temperature sensor and measuring method thereof |
| CN113758507A (en) * | 2020-10-21 | 2021-12-07 | 北京交通大学 | Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber |
| CN115016064A (en) * | 2022-05-27 | 2022-09-06 | 武汉安扬激光技术股份有限公司 | Optical fiber connection method based on single mode fiber and rod-shaped photonic crystal fiber |
| US11756803B2 (en) | 2017-11-11 | 2023-09-12 | Applied Materials, Inc. | Gas delivery system for high pressure processing chamber |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11756803B2 (en) | 2017-11-11 | 2023-09-12 | Applied Materials, Inc. | Gas delivery system for high pressure processing chamber |
| CN109000809A (en) * | 2018-07-17 | 2018-12-14 | 南通大学 | A kind of Mach-Zender interferometer and its making apparatus and production method |
| CN109000809B (en) * | 2018-07-17 | 2019-10-22 | 南通大学 | A kind of Mach-Zender interferometer and its making apparatus and production method |
| CN110749572A (en) * | 2019-10-29 | 2020-02-04 | 广州特种承压设备检测研究院 | Novel graphene optical fiber gas sensor measuring system and method for measuring hydrogen sulfide gas by using same |
| CN111504529A (en) * | 2020-04-24 | 2020-08-07 | 南昌航空大学 | Micro-nano optical fiber nano Newton level mechanical sensor |
| CN113758507A (en) * | 2020-10-21 | 2021-12-07 | 北京交通大学 | Temperature and stress sensor based on few-mode optical fiber and photonic crystal optical fiber |
| CN113340456A (en) * | 2021-07-15 | 2021-09-03 | 中南大学 | Optical fiber temperature sensor and measuring method thereof |
| CN115016064A (en) * | 2022-05-27 | 2022-09-06 | 武汉安扬激光技术股份有限公司 | Optical fiber connection method based on single mode fiber and rod-shaped photonic crystal fiber |
| CN115016064B (en) * | 2022-05-27 | 2024-03-19 | 武汉安扬激光技术股份有限公司 | Optical fiber connection method based on single-mode optical fiber and rod-shaped photonic crystal fiber |
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Application publication date: 20180622 |