CN108981955B - A kind of optical fibre temperature survey apparatus - Google Patents
A kind of optical fibre temperature survey apparatus Download PDFInfo
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- CN108981955B CN108981955B CN201810842925.9A CN201810842925A CN108981955B CN 108981955 B CN108981955 B CN 108981955B CN 201810842925 A CN201810842925 A CN 201810842925A CN 108981955 B CN108981955 B CN 108981955B
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- 239000013307 optical fiber Substances 0.000 title claims abstract description 72
- 239000000835 fiber Substances 0.000 claims abstract description 36
- 239000002121 nanofiber Substances 0.000 claims abstract description 29
- 238000001228 spectrum Methods 0.000 claims abstract description 25
- 238000007747 plating Methods 0.000 claims abstract description 24
- 230000010287 polarization Effects 0.000 claims abstract description 21
- 238000009529 body temperature measurement Methods 0.000 claims abstract description 4
- 230000003287 optical effect Effects 0.000 claims description 30
- 230000008878 coupling Effects 0.000 claims description 12
- 238000010168 coupling process Methods 0.000 claims description 12
- 238000005859 coupling reaction Methods 0.000 claims description 12
- 239000011521 glass Substances 0.000 claims description 10
- 230000005540 biological transmission Effects 0.000 claims description 9
- 230000009365 direct transmission Effects 0.000 claims description 3
- 239000003292 glue Substances 0.000 claims description 3
- 239000007788 liquid Substances 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 8
- 238000005259 measurement Methods 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 238000005253 cladding Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 238000010183 spectrum analysis Methods 0.000 description 1
Classifications
-
- 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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J3/00—Spectrometry; Spectrophotometry; Monochromators; Measuring colours
- G01J3/28—Investigating the spectrum
- G01J3/45—Interferometric spectrometry
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- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
The present invention discloses a kind of optical fibre temperature survey apparatus.The temperature measuring device includes: wideband light source, single-mode optical-fibre coupler, Polarization Controller, optical fiber circulator, refraction index solution covering ellipse micro-nano fiber, the spectrometer for plating silverskin mirror based fiber optica end；The wideband light source is connect with the single-mode optical-fibre coupler, and the light that the wideband light source issues is divided into two beams by the single-mode optical-fibre coupler；The interference of two polarization states of light occurs in the single-mode optical-fibre coupler for the reflected beams described in two beams, obtains interference spectrum；The single-mode optical-fibre coupler is connect with the spectrometer, and the interference spectrum is sent to the spectrometer by the single-mode optical-fibre coupler, and the spectrometer analyzes the interference spectrum, obtains ambient temperature.Remote, high-precision temperature measurement is realized by index liquid covering high birefringence micro-nano fiber.
Description
Technical field
The present invention relates to technical field of optical fiber, more particularly to a kind of optical fibre temperature survey apparatus.
Background technique
Fibre optical sensor has small in size, light-weight, high sensitivity relative to other sensors, not by electromagnetic interference, resistance to
The characteristics of corrosion, is related to the day of national defence and national economy field and people so that the application range of fibre optical sensor is wider
Often life.
Temperature is to indicate the physical quantity of the cold and hot degree of object.In meteorology, material, industry, aviation, medicine and other fields, temperature
The accurate detection of degree has a decisive role.Currently, relatively common fibre optic temperature sensor mainly has cascade connection type, optical fiber
Grating type, Sagnac interference-type.Wherein, interference-type optical fiber grating can detect that the distance for being equivalent to the optical wavelength order of magnitude becomes
Change, compared with other method for sensing, high sensitivity.
The one kind of optic fibre environment as interferometric sensor obtained in recent years since structure is simple, tuning manner is flexible
Extensive research and concern, sensing unit are mostly polarization maintaining optical fibre, and still, traditional polarization maintaining optical fibre is low to the sensitivity of temperature, are passed
Closed-loop shaped structure and transmission-type the sensing optical path of system make senser element not independent in ring, lead to operation when telemeasurement
Inconvenience is not able to satisfy the demand of some remote, high-precision occasions.
Summary of the invention
The object of the present invention is to provide one kind can be realized remote, high-precision optical fibre temperature survey apparatus.
To achieve the above object, the present invention provides following schemes:
A kind of optical fibre temperature survey apparatus, the temperature measuring device include: wideband light source, single-mode optical-fibre coupler, partially
Shake controller, optical fiber circulator, refraction index solution covering ellipse micro-nano fiber, the spectrometer for plating silverskin mirror based fiber optica end；
The wideband light source is connect with the single-mode optical-fibre coupler, and the light that the wideband light source issues passes through the single mode
Fiber coupler is divided into two beams, and a branch of along the first light path direct transmission to the optical fiber circulator, another beam is along the second optical path
It is transmitted in the optical fiber circulator by the Polarization Controller；First optical path is light from the Single-Mode Fiber Coupling
Device is transferred to the transmission optical path of the optical fiber circulator；Second optical path passes through institute from the single-mode optical-fibre coupler for light
The transmission optical path that Polarization Controller is transferred to the optical fiber circulator is stated, first optical path is symmetrically set with second optical path
It sets；
The optical fiber circulator is connect with the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end,
The different light beam of two beam polarization states in the optical fiber circulator obtains coupling light beam after coupling again；
The coupling beam Propagation is into the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end
The reflected beams are obtained by reflection；
After the reflected beams are transmitted to the optical fiber circulator, be divided into two beams, the reflected beams described in two beams respectively along
First optical path and second optic path are to the single-mode optical-fibre coupler；
The interference of two polarization states of light occurs in the single-mode optical-fibre coupler for the reflected beams described in two beams, is done
Relate to spectrum；
The single-mode optical-fibre coupler is connect with the spectrometer, and the single-mode optical-fibre coupler sends out the interference spectrum
It send to the spectrometer, the spectrometer analyzes the interference spectrum, obtains ambient temperature.
Optionally, the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end specifically includes: incident
Single-mode fiber end, oval micro-nano fiber, single mode reflecting segment, the glass tube full of refraction index solution for plating silverskin；
The single mode reflection of the oval micro-nano fiber, the plating silverskin is disposed in the incidence single-mode fiber end
Section；
The ellipse micro-nano fiber is sealed in the glass tube full of refraction index solution；
The glass tube full of refraction index solution and the interface of the incident single-mode fiber end are sealed with AB glue.
Optionally, the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end is arranged in controllable temperature
Environment in；
Temperature in Gradual scene change, the spectrum of the spectrometer collection output, record interference comb spectrum；
The length for calculating the interference pectination Frequency bias is fitted the relationship of the interference pectination Frequency bias variation with temperature
Curve graph；
Temperature measurement is carried out to environment to be measured according to the graph of relation.
The specific embodiment provided according to the present invention, the invention discloses following technical effects: one kind disclosed by the invention
Optical fibre temperature survey apparatus realizes that remote, high-precision temperature measures by index liquid covering high birefringence micro-nano fiber,
It is measured using the method for spectrum analysis, so that measurement result will not influence the precision of measurement because of the variation of ambient temperature, it is real
Show while guaranteeing telemeasurement, has improved the precision of measurement.
Detailed description of the invention
It in order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, below will be to institute in embodiment
Attached drawing to be used is needed to be briefly described, it should be apparent that, the accompanying drawings in the following description is only some implementations of the invention
Example, for those of ordinary skill in the art, without any creative labor, can also be according to these attached drawings
Obtain other attached drawings.
Fig. 1 is the structure chart of optical fibre temperature survey apparatus provided by the invention；
Fig. 2 is the structure of the refraction index solution covering ellipse micro-nano fiber at plating silverskin mirror based fiber optica end provided by the invention
Figure；
Fig. 3 is the waveform diagram that pectination Frequency bias provided by the invention varies with temperature；
Fig. 4 is the curve graph of comb spectrum wavelength with temperature provided by the invention variation.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
The object of the present invention is to provide one kind can be realized remote, high-precision optical fibre temperature survey apparatus.
In order to make the foregoing objectives, features and advantages of the present invention clearer and more comprehensible, with reference to the accompanying drawing and specific real
Applying mode, the present invention is described in further detail.
As shown in Figure 1, a kind of optical fibre temperature survey apparatus, the temperature measuring device includes: wideband light source 1, single-mode optics
Fine coupler 2, Polarization Controller 3, optical fiber circulator 4, the refraction index solution covering ellipse micro-nano light for plating silverskin mirror based fiber optica end
Fine 5, spectrometer 7；
The wideband light source 1 is connect with the single-mode optical-fibre coupler 2, described in the light process that the wideband light source 1 issues
Single-mode optical-fibre coupler 2 is divided into two beams, and a branch of along the first light path direct transmission to the optical fiber circulator 4, another beam is along
Two optical paths are transmitted in the optical fiber circulator 4 by the Polarization Controller 3；First optical path is light from the single mode
Fiber coupler 2 is transferred to the transmission optical path of the optical fiber circulator 4；Second optical path is light from the single mode optical fiber coupling
Clutch 2 is transferred to the transmission optical path of the optical fiber circulator 4 by the Polarization Controller 3, first optical path and described the
Two optical paths are symmetrical arranged；
The optical fiber circulator 4 and the refraction index solution covering ellipse micro-nano fiber 5 at the plating silverskin mirror based fiber optica end connect
It connects, the different light beam of two beam polarization states in the optical fiber circulator 4 obtains coupling light beam after coupling again；
The coupling beam Propagation is into the refraction index solution covering ellipse micro-nano fiber 5 at the plating silverskin mirror based fiber optica end
The reflected beams are obtained by reflection；
After the reflected beams are transmitted to the optical fiber circulator 4, be divided into two beams, the reflected beams described in two beams respectively along
First optical path and second optic path are to the single-mode optical-fibre coupler 2；
The interference of two polarization states of light occurs in the single-mode optical-fibre coupler 2 for the reflected beams described in two beams, obtains
Interference spectrum；
The single-mode optical-fibre coupler 2 is connect with the spectrometer 7, and the single-mode optical-fibre coupler 2 is by the interference light
Spectrum is sent to the spectrometer 7, and the spectrometer 7 analyzes the interference spectrum, obtains ambient temperature.
As shown in Fig. 2, the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end specifically includes: entering
Penetrate single-mode fiber end 8, oval micro-nano fiber 12, single mode reflecting segment 11, the glass tube 10 full of refraction index solution for plating silverskin；
It is anti-that the oval micro-nano fiber 12, the single mode of the plating silverskin are disposed in the incidence single-mode fiber end 8
Penetrate section 11；
The ellipse micro-nano fiber 12 is sealed in the glass tube 10 full of refraction index solution；
The glass tube 10 full of refraction index solution and the interface of the incident single-mode fiber end 8 are sealed with AB glue 9.
As shown in Figure 3 and Figure 4, the refraction index solution covering ellipse micro-nano fiber 5 at the plating silverskin mirror based fiber optica end is arranged
In the environment of controllable temperature, temperature control box 6 specifically is set by controllable temperature environment；
Temperature in Gradual scene change, the spectrum of the acquisition of spectrometer 7 output, record interference comb spectrum；
The drift for calculating the interference pectination spectrum wavelength is fitted the interference comb spectrum wave length shift variation with temperature
Graph of relation；The relation curve that the described dressing spectrum wavelength drift varies with temperature by linear fit or least square method into
Row fitting；
Temperature measurement is carried out to environment to be measured according to the graph of relation.
The core diameter of described incident and outgoing single mode optical fiber is 9 μm, 125 μm of cladding diameter；Oval micro-nano fiber
Length is 0.6cm, a length of 2.8 μm of long axis, and ellipticity 0.7, glass bore is 300 μm, and outer diameter is 500 μm, and length is
5cm。
Principle of the light in transmission process:
Light is divided into two beams by fiber coupler 2, by after two symmetrical optical paths of fiber coupler 2 and circulator 4
Again it is coupled in circulator 4, the polarization state of the control transmission light of Polarization Controller 3 is added in a wherein arm, light beam is again
The oval micro-nano fiber 5 for entering refraction index solution covering after coupling, after the end face 11 by plating silverskin is reflected, again by annular
Device 4 is divided into two beams, and the interference of two polarization states of light occurs in fiber coupler 2 along coupler two-arm, and spectrometer 7 records
Interfere comb spectrum.Receiving ambient temperature when sensing unit influences so that the optical path difference of two polarization states of transmission light changes
When, interference fringe generates movement, as shown in Figure 3.The wave length shift that the record a certain valley value of comb spectrum varies with temperature, fitting comb
The curve that the drift of shape spectrum wavelength varies with temperature, and linear fit is carried out, temperature sensitive coefficient is obtained, as shown in Figure 4.
Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with other
The difference of embodiment, the same or similar parts in each embodiment may refer to each other.For system disclosed in embodiment
For, since it is corresponded to the methods disclosed in the examples, so being described relatively simple, related place is said referring to method part
It is bright.
Used herein a specific example illustrates the principle and implementation of the invention, and above embodiments are said
It is bright to be merely used to help understand method and its core concept of the invention；At the same time, for those skilled in the art, foundation
Thought of the invention, there will be changes in the specific implementation manner and application range.In conclusion the content of the present specification is not
It is interpreted as limitation of the present invention.
Claims (2)
1. a kind of optical fibre temperature survey apparatus, which is characterized in that the temperature measuring device includes: wideband light source, single mode optical fiber
Coupler, Polarization Controller, optical fiber circulator, refraction index solution covering ellipse micro-nano fiber, the light for plating silverskin mirror based fiber optica end
Spectrometer；
The wideband light source is connect with the single-mode optical-fibre coupler, and the light that the wideband light source issues passes through the single mode optical fiber
Coupler is divided into two beams, and a branch of along the first light path direct transmission to the optical fiber circulator, another beam passes through along the second optical path
The Polarization Controller is transmitted in the optical fiber circulator；First optical path is that light is passed from the single-mode optical-fibre coupler
The defeated transmission optical path to the optical fiber circulator；Second optical path passes through for light from the single-mode optical-fibre coupler described inclined
Vibration controller is transferred to the transmission optical path of the optical fiber circulator, and first optical path and second optical path are symmetrical arranged；
The optical fiber circulator is connect with the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end, described
The different light beam of two beam polarization states in optical fiber circulator obtains coupling light beam after coupling again；
The coupling beam Propagation is passed through into the refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end
Reflection obtains the reflected beams；
After the reflected beams are transmitted to the optical fiber circulator, it is divided into two beams, the reflected beams described in two beams are respectively along described
First optical path and second optic path are to the single-mode optical-fibre coupler；
The interference of two polarization states of light occurs in the single-mode optical-fibre coupler for the reflected beams described in two beams, obtains interference light
Spectrum；
The single-mode optical-fibre coupler is connect with the spectrometer, and the interference spectrum is sent to by the single-mode optical-fibre coupler
The spectrometer, the spectrometer analyze the interference spectrum, obtain ambient temperature；
The refraction index solution covering ellipse micro-nano fiber at the plating silverskin mirror based fiber optica end specifically includes: incident single-mode fiber end,
Oval micro-nano fiber, single mode reflecting segment, the glass tube full of refraction index solution for plating silverskin；
The single mode reflecting segment of the oval micro-nano fiber, the plating silverskin is disposed in the incidence single-mode fiber end；
The ellipse micro-nano fiber is sealed in the glass tube full of refraction index solution；
The glass tube full of refraction index solution and the interface of the incident single-mode fiber end are sealed with AB glue.
2. a kind of optical fibre temperature survey apparatus according to claim 1, which is characterized in that plating silverskin mirror based fiber optica end
Refraction index solution covering ellipse micro-nano fiber be arranged in the environment of controllable temperature；
Temperature in Gradual scene change, the spectrum of the spectrometer collection output, record interference comb spectrum；
The length for calculating the interference pectination Frequency bias is fitted the relation curve of the interference pectination Frequency bias variation with temperature
Figure；
Temperature measurement is carried out to environment to be measured according to the graph of relation.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201810842925.9A CN108981955B (en) | 2018-07-27 | 2018-07-27 | A kind of optical fibre temperature survey apparatus |
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| CN201810842925.9A CN108981955B (en) | 2018-07-27 | 2018-07-27 | A kind of optical fibre temperature survey apparatus |
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| CN108981955B true CN108981955B (en) | 2019-10-01 |
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| CN110296767B (en) * | 2019-07-09 | 2021-04-20 | 南京工程学院 | Underwater temperature measuring device based on triangular gap optical fiber structure |
| CN114112313B (en) * | 2021-12-02 | 2024-04-19 | 中国电子科技集团公司第四十六研究所 | Single polarization optical fiber transmission performance testing device and testing method |
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| CN101629855B (en) * | 2008-07-18 | 2012-07-11 | 派克森公司 | Distributed optical fiber sensing system and detection method utilizing same |
| DE102009043547A1 (en) * | 2009-09-30 | 2011-03-31 | Lios Technology Gmbh | Device for space-resolved measurement of temperature in optical fibers, has direction-based refraction unit, and evaluation unit determining temperature of optical fiber from detected Rayleigh- and anti-stoke components of scattered light |
| CN106768278B (en) * | 2017-01-06 | 2020-07-31 | 天津大学 | Distributed optical fiber vibration and temperature dual-physical quantity sensing and positioning system |
| CN107860488B (en) * | 2017-09-25 | 2021-06-25 | 兰州理工大学 | Photonic crystal fiber fast light time advanced temperature sensing method and sensor based on liquid filling |
| CN107607220B (en) * | 2017-09-25 | 2021-01-12 | 兰州理工大学 | Photonic crystal fiber fast light pulse broadening temperature sensing method and sensor based on liquid filling |
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