CN1296676C - Bending sensor capable of simultaneously measuring bending curvature and bending direction - Google Patents
Bending sensor capable of simultaneously measuring bending curvature and bending direction Download PDFInfo
- Publication number
- CN1296676C CN1296676C CNB2005100244261A CN200510024426A CN1296676C CN 1296676 C CN1296676 C CN 1296676C CN B2005100244261 A CNB2005100244261 A CN B2005100244261A CN 200510024426 A CN200510024426 A CN 200510024426A CN 1296676 C CN1296676 C CN 1296676C
- Authority
- CN
- China
- Prior art keywords
- lpfg
- bending
- long period
- period fiber
- fiber grating
- 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.)
- Expired - Fee Related
Links
Images
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
The present invention relates to a bending sensor for simultaneously measuring bending curvature and bending directions, which comprises long-period fiber gratings LPFGa, LPFGb and LPFGc and a single-mode fiber, wherein the long-period fiber gratings LPFGa, LPFGb and LPFGc are mutually cascaded by the single-mode fiber. The long-period fiber grating LPFGc is between the long-period fiber gratings LPFGa and LPFGb during cascading; the resonant wavelengths of the long-period fiber gratings LPFGa and LPFGb are intercrossed into a 45-degree included angle in the most sensitive bending direction. The present invention simultaneously realizes the measurement of bending curvature and bending directions. The sensor has the advantages of small volume and low cost, is completely compatible with fibers, and is easily buried a measured engineering structure.
Description
Technical field
The present invention relates to a kind of sensor of technical field of optical fiber sensing, specifically is a kind of bend sensor of measuring bending curvature and bending direction simultaneously.
Background technology
Long period fiber grating (long period fiber grating:LPFG) is a kind of optical fiber passive bandreject filtering device that just occurred in recent years.Long period fiber grating has without male offspring to reflection, be compatible with optical fiber entirely, volume is little, can imbed advantage such as intellectual material and have in some aspects than the better sensing characteristics of Fiber Bragg Grating FBG.Therefore, long period fiber grating is from once occurring having obtained widespread use at sensory field of optic fibre.The resonance wavelength of the long period fiber grating that ultraviolet light writes in ordinary optic fibre is linear change with the increase of bending curvature.Therefore, this long period fiber grating is a bend sensor preferably.Because the crooked sensitivity of the resonance wavelength of the differently curved direction of long period fiber grating that ultraviolet light commonly used writes much at one, therefore general long period fiber grating bend sensor can only be measured bending curvature and can not differentiate bending direction.Yet, to measure in the application in many practical project, the size but also the needs that not only need sometimes to measure bending curvature are differentiated bending direction.Therefore, not only energy measurement amount of bow but also the bend sensor that can differentiate bending direction (particularly differentiating any bending direction in 360 ° of scopes) have important practical significance to the practical problems that solves engineering survey.A long period fiber grating that in the special fiber of fibre core skew, writes with ultraviolet light, perhaps carry two long period fiber grating that write in the optical fiber at hydrogen and cooperatively interact and to address this problem to a certain extent, can not realize differentiation but these two kinds of methods all can only realize the differentiation of two symmetric curvature directions (promptly be bent upwards or be bent downwardly) any bending direction with certain bending direction correlativity with ultraviolet light.High frequency CO
2Laser pulse can write high-quality long period fiber grating in high-efficiency and low-cost ground in ordinary optic fibre.This long period fiber grating is because CO
2Single survey incident of laser causes grating xsect index distribution inhomogeneous, thereby makes it may have the characteristic of many uniquenesses.
Find through literature search prior art, people such as Y.Liu are at " IEEE Photonics Technol.Lett. " 2000,12,531-533, on " Optical bend sensor based on measurementof resonance mode splitting of long-period fiber grating " (" photon technology wall bulletin ", bend sensor that separates based on the long period fiber grating polarization mode) of delivering.Mention in this article that the long period fiber grating that ultraviolet light writes can be used as bend sensor, but this bend sensor can only be realized the measurement of bending curvature, can not differentiate bending direction.This be because the crooked sensitivity of the resonance wavelength of the differently curved direction of the long period fiber grating that writes of ultraviolet light much at one.
Summary of the invention
The objective of the invention is to overcome the deficiency in the existing crooked sensory technology, proposed a kind of bend sensor of measuring bending curvature and bending direction simultaneously.This bend sensor can be differentiated the bending direction of engineering structure in the bending curvature of measuring tested engineering structure, particularly can realize the differentiation of any bending direction, make it overcome existing other bend sensor and can only measure the deficiency that bending curvature maybe can only be differentiated the bending direction of two symmetries, thereby the real real-time monitoring that realizes engineering structure forms so-called intelligence structure.
The present invention is achieved by the following technical solutions, the present invention includes: long period fiber grating LPFG
A, LPFG
BAnd LPFG
C, single-mode fiber uses single-mode fiber long period fiber grating LPFG
A, LPFG
BAnd LPFG
CCascade constitutes LPFG during the long period fiber grating cascade mutually
CBe in long period fiber grating LPFG
AAnd LPFG
BBetween, and long period fiber grating LPFG
A, LPFG
BResonance wavelength is intersected 45 ° of angles mutually to the most responsive direction of bending.
Long period fiber grating LPFG
AAnd LPFG
BBe two high frequency CO
2The long period fiber grating that laser pulse writes with bending direction correlativity.
Long period fiber grating LPFG
CIt is the long period fiber grating that does not have the bending direction correlativity that a ultraviolet light wrting method writes.
Selecting the principle of grating is LPFG
A, LPFG
BAnd LPFG
CResonance wavelength difference under the room temperature free state can be differentiated resonance wavelength separately to guarantee spectrometer in the BENDING PROCESS.High frequency CO
2The crooked sensitivity of the resonance wavelength of the long period fiber grating that laser pulse writes has tangible bending direction correlativity.The resonance wavelength of the long period fiber grating that ultraviolet light writes is linear change with the increase of bending curvature, and the sensitivity of differently curved direction is identical.Therefore, with two high frequency CO
2Laser writes has the long period fiber grating of strong bending direction correlativity and the long period fiber grating that does not have the bending direction correlativity that other method writes and cooperatively interacts and not only can realize the absolute measurement of amount of bow but also can realize differentiation to any bending direction, wherein high frequency CO
2The long period fiber grating that laser pulse writes is used to differentiate bending direction and another long period fiber grating is used to measure amount of bow.
When the present invention is used to measure bending curvature and bending direction, at first build the device of measuring the long period fiber grating flexural property, with this measurement device high frequency CO
2Two long period fiber grating LPFG that laser pulse writes
AAnd LPFG
BAnd long period fiber grating LPFG who writes with ultraviolet light
CFlexural property, mainly be to measure the crooked sensitivity of its resonance wavelength and amplitude, with the graphing method LPFG that draws to differently curved direction
AAnd LPFG
BResonance wavelength to the crooked sensitivity curve of each circumference bending direction in 360 ° of scopes of circumference; Then above raster stage is unified into sensor of the present invention; Then use the width light source as input, with the spectrometer variation of three Resonant Wavelengths of Long Period Fiber Gratings of monitoring in real time, the variation of measuring a certain moment three Resonant Wavelengths of Long Period Fiber Gratings is again according to LPFG
CThe variation of resonance wavelength and crooked Calculation of Sensitivity thereof go out the size of tested engineering structure bending curvature, according to the LPFG that records
AAnd LPFG
BThe variation of resonance wavelength and the size of bending curvature, and contrast the bending direction that the crooked sensitivity curve that draws is judged tested engineering structure.
The decision problem that bend sensor proposed by the invention has solved the bending direction in the flexural measurement when measuring bending curvature has overcome other bend sensor and can only measure the deficiency that bending curvature maybe can only be differentiated bending direction.As sensing element, volume is little, cost is low, be compatible with optical fiber entirely, can easily imbed this structure of tested engineering, can realize the real-time monitoring to engineering structure, forms so-called intelligence structure with long period fiber grating for this sensor.Therefore, this sensor is expected to obtain to use widely at sensory field of optic fibre.
Description of drawings
Fig. 1 is a structural representation of the present invention
Fig. 2 cascade-connection long period fiber grating cross sectional representation, max and min represent high frequency CO respectively
2Direction and least responsive direction that the Resonant Wavelengths of Long Period Fiber Gratings that laser pulse writes is the most responsive to bending
Embodiment
As depicted in figs. 1 and 2, the present invention includes: two high frequency CO
2The long period fiber grating LPFG that laser pulse writes with bending direction correlativity
A1, LPFG
B2 and long period fiber grating LPFG that do not have the bending direction correlativity that the ultraviolet light wrting method writes
CThe 4 mutual cascades of 3 usefulness single-mode fibers constitute.Long period fiber grating LPFG during three long period fiber grating cascades
C3 are in long period fiber grating LPFG
A1, LPFG
BBetween 2, and long period fiber grating LPFG
A1, LPFG
B2 resonance wavelength is intersected 45 ° of angles mutually to the most responsive direction of bending.
Long period fiber grating LPFG
A1, LPFG
B2 is high frequency CO
2The long period fiber grating that laser pulse writes with bending direction correlativity.Long period fiber grating LPFG
C3 long period fiber grating that do not have the bending direction correlativity that write for the ultraviolet light wrting method.Long period fiber grating LPFG
A1, LPFG
B2 and LPFG
C3 resonance wavelengths under the room temperature free state are variant, guarantee that spectrometer in the BENDING PROCESS can differentiate resonance wavelength separately.
Claims (6)
1, a kind of bend sensor of measuring bending curvature and bending direction simultaneously comprises: two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2) and the long period fiber grating LPFG that the ultraviolet light wrting method writes
C(3), single-mode fiber (4) is characterized in that, uses single-mode fiber (4) two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2) and the long period fiber grating LPFG that the ultraviolet light wrting method writes
C(3) cascade mutually, the long period fiber grating LPFG that the ultraviolet light wrting method writes during cascade
C(3) be in two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2) between, and two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2) resonance wavelength is intersected 45 ° of angles mutually to the most responsive direction of bending.
2, the bend sensor of measuring bending curvature and bending direction simultaneously according to claim 1 is characterized in that, two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2), the resonance wavelength difference has the bending direction correlativity.
3, the bend sensor of measuring bending curvature and bending direction simultaneously according to claim 1 is characterized in that, the long period fiber grating LPFG that the ultraviolet light wrting method writes
C(3), there is not the bending direction correlativity.
4, the bend sensor of measuring bending curvature and bending direction simultaneously according to claim 1 is characterized in that, two high frequency CO
2The long period fiber grating LPFG that laser pulse writes
A(1), LPFG
B(2) and the long period fiber grating LPFG that the ultraviolet light wrting method writes
C(3) the resonance wavelength difference under the room temperature free state guarantees that spectrometer in the BENDING PROCESS can differentiate resonance wavelength separately.
5, the bend sensor of measuring bending curvature and bending direction simultaneously according to claim 2 is characterized in that, described two high frequency CO
2The long period fiber grating that laser pulse writes, the crooked sensitivity of its resonance wavelength has tangible bending direction correlativity.
6, the bend sensor of measuring bending curvature and bending direction simultaneously according to claim 3 is characterized in that, the long period fiber grating LPFG that described ultraviolet light wrting method writes
C(3), its resonance wavelength is linear change with the increase of bending curvature, and the sensitivity of differently curved direction is identical.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100244261A CN1296676C (en) | 2005-03-17 | 2005-03-17 | Bending sensor capable of simultaneously measuring bending curvature and bending direction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2005100244261A CN1296676C (en) | 2005-03-17 | 2005-03-17 | Bending sensor capable of simultaneously measuring bending curvature and bending direction |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1664495A CN1664495A (en) | 2005-09-07 |
| CN1296676C true CN1296676C (en) | 2007-01-24 |
Family
ID=35035694
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2005100244261A Expired - Fee Related CN1296676C (en) | 2005-03-17 | 2005-03-17 | Bending sensor capable of simultaneously measuring bending curvature and bending direction |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1296676C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101713726B (en) * | 2009-09-23 | 2011-06-15 | 南京航空航天大学 | Packaging body of cascade fiber grating sensor for degrading monitoring of ammonia nitrogen sewage and manufacturing method thereof |
| CN102466469A (en) * | 2010-11-04 | 2012-05-23 | 西安金和光学科技有限公司 | Measuring device of spring type bending parameter based on fiber bending loss and method thereof |
| CN103123254B (en) * | 2013-02-07 | 2015-05-27 | 南开大学 | Two-dimensional bending vector sensor based on fiber grating interference structure |
| CN105423953A (en) * | 2015-12-23 | 2016-03-23 | 中国计量学院 | Embedded spherical structure long-period fiber grating curvature sensor |
| CN108225207A (en) * | 2017-12-27 | 2018-06-29 | 武汉华星光电半导体显示技术有限公司 | The acquisition methods of the flexuosity amount of flexible display apparatus and flexible display panels |
| CN109000687B (en) * | 2018-07-19 | 2021-01-01 | 西南交通大学 | Curvature demodulation device and method based on core-shift phase-shift fiber grating |
| CN113156573B (en) * | 2021-03-29 | 2023-02-17 | 江苏大学 | Orthogonal long-period fiber grating and application thereof in sensing bending |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61105409A (en) * | 1984-10-30 | 1986-05-23 | Matsushita Electric Ind Co Ltd | Measuring instrument for quantity of end curvature |
| CN1074754A (en) * | 1991-12-30 | 1993-07-28 | 克隆恩工业公司 | High-resolution compact optical sensor for scanning three-dimensional shapes |
| CN1153901A (en) * | 1996-01-06 | 1997-07-09 | 哈尔滨工业大学 | Curved surface shape measuring method |
| US20030055435A1 (en) * | 2000-11-27 | 2003-03-20 | Barrick Earl Frederick | Orthopaedic implant shaper |
-
2005
- 2005-03-17 CN CNB2005100244261A patent/CN1296676C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61105409A (en) * | 1984-10-30 | 1986-05-23 | Matsushita Electric Ind Co Ltd | Measuring instrument for quantity of end curvature |
| CN1074754A (en) * | 1991-12-30 | 1993-07-28 | 克隆恩工业公司 | High-resolution compact optical sensor for scanning three-dimensional shapes |
| CN1153901A (en) * | 1996-01-06 | 1997-07-09 | 哈尔滨工业大学 | Curved surface shape measuring method |
| US20030055435A1 (en) * | 2000-11-27 | 2003-03-20 | Barrick Earl Frederick | Orthopaedic implant shaper |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1664495A (en) | 2005-09-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Urrutia et al. | A comprehensive review of optical fiber refractometers: Toward a standard comparative criterion | |
| CN1296676C (en) | Bending sensor capable of simultaneously measuring bending curvature and bending direction | |
| Xu et al. | Recent developments in micro-structured fiber optic sensors | |
| Wang et al. | A high-temperature humidity sensor based on a singlemode-side polished multimode-singlemode fiber structure | |
| CN108680531B (en) | Titania film coating inclined optical fiber grating refractive index sensor and detection system | |
| Li et al. | Simultaneous measurement of refractive index and temperature using thinned fiber based Mach–Zehnder interferometer | |
| Padden et al. | Coupling in a twin-core microstructured polymer optical fiber | |
| CN201740734U (en) | Refractive index sensor based on fiber Bragg grating | |
| CN1289893C (en) | Method for simultaneously measuring bending curvature and bending direction | |
| Stajanca et al. | Strain sensing with femtosecond inscribed FBGs in perfluorinated polymer optical fibers | |
| CN210953331U (en) | Novel U-shaped cascade long-period fiber grating sensor | |
| Chen et al. | Temperature-insensitive gas pressure sensor based on photonic crystal fiber interferometer | |
| CN102737713A (en) | Two-dimensional integrated optical fiber online storage based on linear array multi-core optical fiber | |
| Teng et al. | Refractive index sensor based on multi-mode plastic optical fiber with long period grating | |
| CN100451618C (en) | Method and device for measuring temp. self-compensation refraction index based on ultralong period optical fiber raster | |
| CN109324020A (en) | A kind of salinity and method for manufacturing refractive index sensor based on micro-nano fiber roll resonator | |
| Pang et al. | Cladding-mode resonance of a double-cladding fiber at a near modal cut-off wavelength for RI sensing | |
| Woyessa et al. | Simultaneous measurement of temperature and humidity with microstructured polymer optical fiber Bragg gratings | |
| CN1624443A (en) | Long period fiber-optical grating temperature sensor | |
| CN103941330A (en) | Composite structure long-period fiber grating | |
| Shi et al. | Simultaneous measurement of refractive index and temperature base on three-beam interferometric fiber-optic | |
| Wang et al. | Simulation of Refractive Index Sensor Based on Microring Resonator | |
| CN216348692U (en) | Asymmetric peanut-shaped optical fiber MZI temperature and refractive index sensing system | |
| CN203299121U (en) | Unmarked optical sensor on end face of optical fiber based on single-multiple-mode optical fiber coupling | |
| CN2807226Y (en) | Long period optical fiber grating temperature sensor |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070124 Termination date: 20100317 |