CN202648830U - A distributed fiber sensing device based on Brillouin scattering - Google Patents
A distributed fiber sensing device based on Brillouin scattering Download PDFInfo
- Publication number
- CN202648830U CN202648830U CN201220268864.8U CN201220268864U CN202648830U CN 202648830 U CN202648830 U CN 202648830U CN 201220268864 U CN201220268864 U CN 201220268864U CN 202648830 U CN202648830 U CN 202648830U
- Authority
- CN
- China
- Prior art keywords
- light source
- pump light
- module
- optical switch
- source
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn - After Issue
Links
Images
Landscapes
- Optical Transform (AREA)
- Length Measuring Devices By Optical Means (AREA)
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
The utility model discloses a distributed fiber sensing device based on Brillouin scattering. The distributed fiber sensing device comprises a first detecting light source, a second detecting light source, a first pump light source, a second pump light source, a first optical switch module, a second optical switch module, a first coupler, a second coupler, a frequency measuring module, a detecting light outputting and signal processing module, a pump light outputting module, and a sensing fiber module. The first detecting light source and the first pump light source, or the second detecting light source and the second pump light source are selected as a light source of a Brillouin optical time domain analysis through the first optical switch module and the second optical switch module, so that a device simultaneously measuring strain and temperature by using a single kind of sensing fiber is achieved, resolving a problem of cross sensitive effect between temperature and strain in Brillouin distributed fiber sensing. The device has characteristics of simple structure, low cost, no special requirement for specification of a sensing fiber, and wide application range and is especially suitable for distributed on-line monitoring application of constructed engineering.
Description
Technical field
The utility model relates to a kind of distribution type optical fiber sensing equipment based on Brillouin scattering, especially relates to a kind of distribution type optical fiber sensing equipment of measuring simultaneously temperature and strain.
Background technology
Distributed fiberoptic sensor has important application in the safety monitoring of the important infrastructures such as electric power, bridge, dam, petrochemical industry.Compare with the distributed fiberoptic sensor based on Raman scattering, longer based on the measuring distance of the distributed fiberoptic sensor of Brillouin scattering, measuring accuracy is higher, and realize temperature and stress measurement, so this product has enjoyed people to pay close attention to since coming out.
Distributed fiberoptic sensor based on Brillouin scattering has two types: Brillouin light time domain reflection technology (Brillouin Opitcal Time Domain Reflection, BOTDR) and Brillouin optical time domain analysis technology (Brillouin Optical Time Domain Analysis, BOTDA).Wherein BOTDR is single-ended measurement, and is simple in structure, but its detection is faint spontaneous brillouin scattering light, is difficult to realize long distance, high-acruracy survey; BOTDA then is double-end measurement, detection be stronger stimulated Brillouin scattering light, its measuring distance and precision are better than BOTDR, are the present Fibre Optical Sensors of tool application prospect.The system architecture of typical BOTDA comprises probe source, pump light source, coupling mechanism 1, coupling mechanism 2, coupling mechanism 3, external modulator, scrambler, circulator, frequency measurement module, acquisition of signal module, sensor fibre as shown in Figure 1.Wherein the wavelength of probe source and pump light source is very approaching, its typical difference on the frequency is about 9 ~ 16GHz, probe source and pump light source enter coupling mechanism 3 respectively after coupling mechanism 1, coupling mechanism 2 are told part light, and realized the measurement of the difference on the frequency of probe source and pump light source by the frequency measurement module, external modulator generally adopts electrooptic modulator, for generation of pulsed optical signals, scrambler is used for eliminating the impact of polarization, pulsed light is relative to pump light being incident to sensor fibre, and brillouin scattering signal is measured by the acquisition of signal module behind circulator.
Distributed fiberoptic sensor based on Brillouin scattering utilizes the development of optical fiber Brillouin backscattering effect.Brillouin scattering effect in the optical fiber is to inject a kind of nonlinear light scatter phenomenon that intercouples and act on and produce between the elasticity acoustic wavefield of light wave fields and optical fiber, wherein Brillouin shift v
BWith wavelength X, velocity of sound v
AWith refractive index n and relational expression be:
When variation of ambient temperature or optical fiber generation deformation, velocity of sound v in the optical fiber
AAll can change with the refractive index n of light thereupon, thereby make Brillouin shift v
BChange.Brillouin shift variable quantity and environment temperature, fibre strain are linear:
Δv
B=C
εΔε+C
TΔT （2）
Δ v in the formula
BBe the Brillouin shift variable quantity, Δ ε is the optical fiber axial strain, and Δ T is fiber optic temperature, C
εAnd C
TBe respectively strain and the temperature coefficient of Brillouin frequency shifts.The strain of Brillouin frequency shifts and temperature coefficient C
εAnd C
TExcept relevant with optical fiber structure, also relevant with optical maser wavelength, and optical maser wavelength difference is larger, and then the strain of Brillouin frequency shifts and temperature coefficient difference are larger.
Because Brillouin shift is responsive simultaneously to temperature and strain, in the actual application such as health status monitoring, need to solve this cross-sensitivity, these people are proposed many solutions.As, the people such as Bao X adopt polarization maintaining optical fibre, photonic crystal fiber, the special fibers such as large effective area fiber are as measuring optical fiber, utilize a plurality of Brillouin shifts peak to come separation temperature and strain value (" Simultaneous strain and temperature measurements with polarization-maintaining fibers and their error analysis by use of a distributed Brillouin loss system; " Optics letters, 29 (12): 1342-1344,2004), but because special fiber is mostly expensive, availability is poor, the long range measurements high cost.And for example, application number is that 201010229960.7 utility model patent discloses at least two measuring optical fiber that the Brillouin shift temperature coefficient is different with stress coefficient that a kind of utilization is set up in parallel, and realize the measurement of the Brillouin shift variable quantity of two optical fiber by the photoswitch switching mode, solve Brillouin shift to the cross-sensitivity of temperature and strain by Simultaneous Equations, but need to lay in advance two types single-mode fiber.
For monitoring and measuring applications such as long distance high-voltage power cable, sea floor optoelectronic composite cables, especially built Larger Engineering Projects, generally only laid a kind of single-mode fiber (for example G652), how utilizing the single-mode fiber of single kind to realize separating of temperature and strain, is that large-scale application is promoted the key based on the distributed fiberoptic sensor of Brillouin scattering.
The utility model content
Technical problem to be solved in the utility model provides a kind of single-mode fiber of single kind that utilizes and realizes temperature and the simultaneously-measured distribution type optical fiber sensing equipment of strain.
The utility model solves the problems of the technologies described above the technical scheme that adopts: a kind of distribution type optical fiber sensing equipment based on Brillouin scattering, comprise the first probe source, the first pump light source, the first coupling mechanism, the second coupling mechanism, the frequency measurement module, survey light output and signal processing module, the pump light output module, the sensor fibre module, also comprise the second probe source, the second pump light source, the first optical switch module and the second optical switch module, described the first probe source be connected probe source and be connected with two light signal input ends of the first optical switch module respectively, described the first pump light source be connected pump light source and be connected with two light signal input ends of the second optical switch module respectively, the light signal output end of described the first optical switch module is connected with the input end of the first coupling mechanism, the light signal output end of described the second optical switch module is connected with the input end of the second coupling mechanism, described frequency measurement module respectively with the first coupling mechanism be connected an output terminal of coupling mechanism and be connected, described the first coupling mechanism be connected another output terminal of coupling mechanism and be connected input end with the pump light output module with the output of described detection light and signal processing module respectively and be connected, the output of described detection light and signal processing module are connected output terminal and are connected with the two ends of sensor fibre module respectively with the pump light output module.
Described the first probe source has different wavelength coverages with the first pump light source from the second probe source and the second pump light source, and the wavelength interval is not less than 190nm.Further, if the first probe source and the first pump light source are selected the LASER Light Source of (1550 ± 30) nm scope, the second probe source and the second pump light source then need be selected the LASER Light Source of (1310 ± 20) nm scope or the LASER Light Source of (1064 ± 20) nm scope.
Described the first optical switch module and the second optical switch module can select the first probe source and the first pump light source or the second probe source and the second pump light source as the light source of Brillouin optical time domain analysis instrument.
The Brillouin optical time domain analysis instrument needs probe source and pump light source to incide in opposite directions on the sensor fibre, utilize the first probe source and the first pump light source Brillouin optical time domain analysis instrument light source that partners in the technical program, utilize the second probe source and the second pump light source to form another to Brillouin's time-domain analysis instrument light source, other device such as frequency measurement module, survey light output and signal processing module, the pump light output module, the core optical-electric modules such as coupling mechanism then share, switching by the first photoswitch and the second optical switch module, realized the different Brillouin optical time domain analysis instrument of two cover optical maser wavelengths with lower cost, can obtain the Brillouin shift variable quantity distribution Δ v of two groups of sensor fibres this moment
B1(z) and Δ v
B2(z).Because the optical maser wavelength of the first probe source and the first pump light source and the second probe source and the second pump light source has larger difference, the coefficient of strain C of their Brillouin frequency shifts
ε 1, C
ε 2With temperature coefficient C
T1, C
T2Difference, this moment, Simultaneous Equations can obtain sensor fibre strain value Δ ε (z) and temperature value Δ T (z) everywhere along the line:
The beneficial effects of the utility model: (1) provides a kind of sensor fibre that utilizes single kind to realize the device of strain and temperature simultaneously measuring, has solved the problem of temperature and strain cross-sensitivity in the brillouin distributed optical fiber sensing; (2) this device has shared the core optical-electric modules such as frequency measurement module, detection light output and signal processing module, pump light output module, coupling mechanism, has only increased a pair of light source, and simple in structure, cost is low; (3) this device does not have specific (special) requirements to the specification of sensor fibre, and is applied widely, and the distributed on line monitoring that especially is fit to built engineering is used.
Description of drawings
Fig. 1 is the structural representation of typical Brillouin optical time domain analysis instrument;
Fig. 2 is the structural representation of a kind of distribution type optical fiber sensing equipment based on Brillouin scattering of the utility model;
Fig. 3 is the structural representation that the utility model embodiment 1 surveys light output and signal processing module;
The relation of Brillouin shift and fibre strain and temperature when Fig. 4 is the utility model embodiment 1 optical maser wavelength 1550nm;
The relation of Brillouin shift and fibre strain and temperature when Fig. 5 is the utility model embodiment 1 optical maser wavelength 1310nm.
Embodiment
Embodiment is described in further detail the utility model below in conjunction with accompanying drawing.
Embodiment 1:
As shown in Figures 2 and 3, a kind of distribution type optical fiber sensing equipment based on Brillouin scattering comprises the first probe source 1, the second probe source 2, the first pump light source 3, the second pump light sources 4, the first optical switch modules 5, the second optical switch module 6, the first coupling mechanism 7, the second coupling mechanisms 8, frequency measurement module 9, survey light output and signal processing module 10, pump light output module 11 and sensor fibre module 12.The first probe source 1, the second probe source 2, the first pump light source 3 and the second pump light source 4 are the narrow-linewidth laser light source, and its typical live width is less than 1MHz; The first probe source 1 and the first pump light source 3 Brillouin optical time domain analysis instrument light source that partners wherein, select the upper the most frequently used optical maser wavelength of communication, the wavelength Application Range is (1550 ± 30) nm, particularly, the first probe source 1 is selected the narrow linewidth laser of 1550.12nm in the present embodiment, the first pump light source 3 is selected the narrow linewidth laser of 1550.04nm, by temperature or piezoelectric ceramics PZT is tuning or the frequency displacement device so that the difference on the frequency of the first probe source 1 and the first pump light source 3 covers Brillouin's frequency spectrum (about 9 ~ 13GHz 1550nm) of optical fiber; And the second probe source 2 and the second pump light source 4 form another to Brillouin optical time domain analysis instrument light source, its wavelength coverage and first pair of Brillouin optical time domain analysis instrument optical source wavelength have certain distance, present embodiment medium wavelength Application Range is (1310 ± 20) nm, particularly, the second probe source 2 is selected the Nd:YLF laser instrument of 1310.07nm, the second pump light source 4 is selected the Nd:YLF laser instrument of 1310.00nm, by temperature or piezoelectric ceramics PZT is tuning or the frequency displacement device so that the difference on the frequency of the second probe source 2 and the second pump light source 4 covers Brillouin's frequency spectrum (about 11 ~ 15GHz 1310nm) of optical fiber.The first optical switch module 5 and the second optical switch module 6 are 2 * 1 photoswitches, the first probe source 1 be connected probe source 2 and be connected with the light signal input end 51,52 of the first optical switch module 5 respectively, the first pump light source 3 be connected pump light source 4 and be connected with the light signal input end 61,62 of the second optical switch module 6 respectively, can select the first probe source 1 and the first pump light source 3 or the second probe source 2 and the second pump light source 4 as the light source of Brillouin optical time domain analysis instrument by circuit control; The light signal output end 53 of the first optical switch module 5 is connected with the input end of the first coupling mechanism 7, and the light signal output end 63 of the second optical switch module 6 is connected with the input end of the second coupling mechanism 8; Frequency measurement module 9 respectively with the first coupling mechanism 7 be connected an output terminal of coupling mechanism 8 and be connected, be used for measuring the difference on the frequency of probe source and pump light source; The first coupling mechanism 7 be connected coupling mechanism 8 another output terminal respectively with survey the input end that light output and signal processing module 10 be connected with the pump light output module and be connected, wherein surveying light output and signal processing module 10 receives for generation of pulse signal and backscatter signals, comprise pulse-modulator 101, circulator 102 and high speed signal detector 103 in the output of detection light and the signal processing module 10 in this enforcement, as shown in Figure 3.If measuring distance is long, surveying in light output and the signal processing module 10 to increase image intensifer or scrambler, surveys optical output power and increases the polarization homogeneity to improve.Pump light output module 11 mainly is that pump light is processed and exported, and generally includes the devices such as scrambler, optical attenuator.Survey the output terminal that light is exported and signal processing module 10 is connected with the pump light output module and be connected with the two ends of sensor fibre module 12 respectively, sensor fibre module 12 is the single mode 28e+ optical fiber of Coring company in this enforcement.
Form two cover optical maser wavelengths different Brillouin optical time domain analysis instrument with the first pump light source 3 and the second probe source 2 with the second pump light source 4 by the first probe source 1, to same sensor fibre module 12 tests, can obtain the Brillouin shift variable quantity distribution Δ v of two groups of sensor fibres
B1(z) and Δ v
B2(z).According to test, by the Brillouin optical time domain analysis instrument that the first probe source 1 and the first pump light source 3 form, the optical source wavelength scope is 1550nm, and this moment, the coefficient of strain and the temperature coefficient of Brillouin shift were respectively C
ε 1=467MHz/%, C
T1=0.98MHz/ ℃, as shown in Figure 4; By another Brillouin optical time domain analysis instrument that the second probe source 2 and the second pump light source 4 form, the optical source wavelength scope is 1310nm, and this moment, the coefficient of strain and the temperature coefficient of Brillouin shift were respectively C
ε 2=500MHz/%, C
T2=1.16MHz/ ℃, as shown in Figure 5; The coefficient of strain C of the Brillouin shift of the Brillouin optical time domain analysis instrument that two optical maser wavelength is different
ε 1, C
ε 2With temperature coefficient C
T1, C
T2Larger difference is arranged, can obtain sensor fibre strain value Δ ε (z) and temperature value Δ T (z) everywhere along the line by Simultaneous Equations, realize strain and temperature simultaneously measuring to the sensor fibre of single kind, solved the problem of temperature and strain cross-sensitivity in the brillouin distributed optical fiber sensing.
Embodiment 2:
The device of present embodiment is similar to Example 1, the wavelength coverage of different is in the present embodiment the second probe source 2 and the second pump light source 4 is (1064 ± 20) nm, particularly, the second probe source 2 is selected the Nd:YAG laser instrument of 1064.26nm, the second pump light source 4 is selected the Nd:YAG laser instrument of 1064.21nm, by temperature or piezoelectric ceramics PZT is tuning or the frequency displacement device so that the difference on the frequency of the second probe source 2 and the second pump light source 4 covers Brillouin's frequency spectrum (about 13 ~ 17GHz 1064nm) of optical fiber.
The above is preferred embodiment of the present utility model only, should not be construed as the restriction to the utility model protection domain.All within spirit of the present utility model and principle, any type of distortion of doing, be equal to replacement, improvement etc. and all should be included within the protection domain of the present utility model.
Claims (4)
1. distribution type optical fiber sensing equipment based on Brillouin scattering, comprise the first probe source, the first pump light source, the first coupling mechanism, the second coupling mechanism, the frequency measurement module, survey light output and signal processing module, the pump light output module, the sensor fibre module, characterized by further comprising the second probe source, the second pump light source, the first optical switch module and the second optical switch module, described the first probe source be connected probe source and be connected with two light signal input ends of the first optical switch module respectively, described the first pump light source be connected pump light source and be connected with two light signal input ends of the second optical switch module respectively, the light signal output end of described the first optical switch module is connected with the input end of the first coupling mechanism, the light signal output end of described the second optical switch module is connected with the input end of the second coupling mechanism, described frequency measurement module respectively with the first coupling mechanism be connected an output terminal of coupling mechanism and be connected, described the first coupling mechanism be connected another output terminal of coupling mechanism and be connected input end with the pump light output module with the output of described detection light and signal processing module respectively and be connected, the output of described detection light and signal processing module are connected output terminal and are connected with the two ends of sensor fibre module respectively with the pump light output module.
2. a kind of distribution type optical fiber sensing equipment based on Brillouin scattering as claimed in claim 1, it is characterized in that described the first probe source has different wavelength coverages with the first pump light source from the second probe source and the second pump light source, and the wavelength interval is not less than 190nm.
3. a kind of distribution type optical fiber sensing equipment based on Brillouin scattering as claimed in claim 1 is characterized in that described the first optical switch module and the second optical switch module can select the first probe source and the first pump light source or the second probe source and the second pump light source as the light source of Brillouin optical time domain analysis instrument.
4. a kind of distribution type optical fiber sensing equipment based on Brillouin scattering as claimed in claim 3 is characterized in that described the first optical switch module and the second optical switch module are 2 * 1 photoswitches, is provided with two light signal input ends and a light signal output end.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201220268864.8U CN202648830U (en) | 2012-06-08 | 2012-06-08 | A distributed fiber sensing device based on Brillouin scattering |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201220268864.8U CN202648830U (en) | 2012-06-08 | 2012-06-08 | A distributed fiber sensing device based on Brillouin scattering |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN202648830U true CN202648830U (en) | 2013-01-02 |
Family
ID=47417925
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201220268864.8U Withdrawn - After Issue CN202648830U (en) | 2012-06-08 | 2012-06-08 | A distributed fiber sensing device based on Brillouin scattering |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN202648830U (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721484A (en) * | 2012-06-08 | 2012-10-10 | 宁波诺驰光电科技发展有限公司 | Distributed optical fiber sensing device based on brillouin scattering |
| CN103063325A (en) * | 2013-01-16 | 2013-04-24 | 电子科技大学 | BOTDA temperature and strain simultaneous measurement method based on LEAF optical fiber |
| CN103292831A (en) * | 2013-05-31 | 2013-09-11 | 武汉康特圣思光电技术有限公司 | Single-ended Brillouin optical time-domain analysis sensor with fiber grating reflection filter structure |
| CN105067146A (en) * | 2015-03-20 | 2015-11-18 | 深圳市迅捷光通科技有限公司 | Stimulated raman scattering suppression device, method and distributed optical fiber sensing system |
| CN105588661A (en) * | 2015-11-12 | 2016-05-18 | 哈尔滨工程大学 | Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating |
| CN107328559A (en) * | 2017-08-14 | 2017-11-07 | 桂林聚联科技有限公司 | A kind of loss of fibre-optical connection measurement apparatus and measuring method |
| CN112797972A (en) * | 2020-12-15 | 2021-05-14 | 浙江大学 | Dual-wavelength interactive bypassing optical fiber gyroscope device and design method |
| CN114812667A (en) * | 2022-03-18 | 2022-07-29 | 张鹏 | Transmission conductor detection method, structure and device based on multiple optical fibers |
-
2012
- 2012-06-08 CN CN201220268864.8U patent/CN202648830U/en not_active Withdrawn - After Issue
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102721484A (en) * | 2012-06-08 | 2012-10-10 | 宁波诺驰光电科技发展有限公司 | Distributed optical fiber sensing device based on brillouin scattering |
| CN102721484B (en) * | 2012-06-08 | 2014-07-23 | 浙江中欣动力测控技术有限公司 | Distributed optical fiber sensing device based on brillouin scattering |
| CN103063325B (en) * | 2013-01-16 | 2014-11-19 | 电子科技大学 | BOTDA temperature and strain simultaneous measurement method based on LEAF optical fiber |
| CN103063325A (en) * | 2013-01-16 | 2013-04-24 | 电子科技大学 | BOTDA temperature and strain simultaneous measurement method based on LEAF optical fiber |
| CN103292831B (en) * | 2013-05-31 | 2016-01-20 | 武汉康特圣思光电技术有限公司 | The single-ended Brillouin optical time domain analysis sensor of fiber grating reflection filter structure |
| CN103292831A (en) * | 2013-05-31 | 2013-09-11 | 武汉康特圣思光电技术有限公司 | Single-ended Brillouin optical time-domain analysis sensor with fiber grating reflection filter structure |
| CN105067146A (en) * | 2015-03-20 | 2015-11-18 | 深圳市迅捷光通科技有限公司 | Stimulated raman scattering suppression device, method and distributed optical fiber sensing system |
| CN105588661A (en) * | 2015-11-12 | 2016-05-18 | 哈尔滨工程大学 | Device for simultaneous measurement of single-point and regional temperatures through preserving polarization fiber grating |
| CN105588661B (en) * | 2015-11-12 | 2018-07-31 | 哈尔滨工程大学 | A kind of device for realizing that single-point and regional temperature measure simultaneously using polarization-maintaining fiber grating |
| CN107328559A (en) * | 2017-08-14 | 2017-11-07 | 桂林聚联科技有限公司 | A kind of loss of fibre-optical connection measurement apparatus and measuring method |
| CN107328559B (en) * | 2017-08-14 | 2023-03-21 | 桂林聚联科技有限公司 | Optical fiber connection loss measuring device and measuring method |
| CN112797972A (en) * | 2020-12-15 | 2021-05-14 | 浙江大学 | Dual-wavelength interactive bypassing optical fiber gyroscope device and design method |
| CN114812667A (en) * | 2022-03-18 | 2022-07-29 | 张鹏 | Transmission conductor detection method, structure and device based on multiple optical fibers |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102721484B (en) | Distributed optical fiber sensing device based on brillouin scattering | |
| CN202648830U (en) | A distributed fiber sensing device based on Brillouin scattering | |
| CN102798411B (en) | System and method for distributed optical fibre sensing measurement based on Brillouin scattering | |
| CN103674086B (en) | Measure entirely with method and the device of weak optical fiber Bragg grating temperature and strain based on Brillouin scattering simultaneously | |
| CN101900611B (en) | Device and method for simultaneously measuring temperature and stress by using distributed optical fiber sensor | |
| CN103674117B (en) | Measure entirely method and device with weak optical fiber Bragg grating temperature and strain based on Raman scattering simultaneously | |
| CN102607621A (en) | Distributed optical fiber Brillouin sensing device and method thereof for detecting temperature and strain synchronously | |
| CN102706477B (en) | Distributed optical fiber sensing device and method for simultaneously measuring temperature and strain | |
| CN102221421B (en) | Distributed optical fiber sensor for temperature and strain measurement and measuring method | |
| CN103591971B (en) | A kind of localization method of fiber grating | |
| CN101555990A (en) | Safety monitoring system of long-distance pipeline | |
| CN102226703A (en) | Distributed fiber multi-parameter sensor and multi-parameter measuring method | |
| CN105371785B (en) | A kind of curvature measurement method | |
| CN202648831U (en) | Distributed optical fiber sensing device simultaneously measuring temperature and strain | |
| CN104568019A (en) | Multimode fiber-based method and multimode fiber-based system for simultaneously measuring temperature and strain | |
| CN102944253A (en) | System capable of synchronously measuring transverse pressure and temperature of fiber grating based on polarization measurement | |
| Su et al. | Double-parameters optical fiber sensor based on spherical structure and multimode fiber | |
| Xu et al. | Reflective liquid level sensor based on parallel connection of cascaded FBG and SNCS structure | |
| CN202041323U (en) | Distributed multi-parameter optical fiber sensor | |
| CN201955173U (en) | Distributed optical fiber temperature-strain measurement sensor | |
| CN102620856B (en) | Distributed optical fiber Brillouin strain and temperature sensor | |
| CN104729750A (en) | Distributed optical fiber temperature sensor based on Brillouin scattering | |
| CN202533198U (en) | Distributed fiber Brillouinstrain strain and temperature sensor | |
| CN201654405U (en) | FBG demodulating system | |
| Weng et al. | Distributed temperature and strain sensing using spontaneous Brillouin scattering in optical few-mode fibers |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20130102 Effective date of abandoning: 20140723 |
|
| AV01 | Patent right actively abandoned |
Granted publication date: 20130102 Effective date of abandoning: 20140723 |
|
| RGAV | Abandon patent right to avoid regrant |