CN111175899A - Single-core disturbance sensor and manufacturing method thereof - Google Patents
Single-core disturbance sensor and manufacturing method thereof Download PDFInfo
- Publication number
- CN111175899A CN111175899A CN201911187652.XA CN201911187652A CN111175899A CN 111175899 A CN111175899 A CN 111175899A CN 201911187652 A CN201911187652 A CN 201911187652A CN 111175899 A CN111175899 A CN 111175899A
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- sensor
- mode optical
- optical fibers
- mode
- 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.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/25—Preparing the ends of light guides for coupling, e.g. cutting
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
- G01H9/004—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means using fibre optic sensors
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01V—GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS
- G01V8/00—Prospecting or detecting by optical means
- G01V8/10—Detecting, e.g. by using light barriers
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geophysics (AREA)
- Optical Transform (AREA)
Abstract
The invention discloses a single-core disturbance sensor and a manufacturing method thereof, wherein the sensor comprises a sensor head and a sensor body, the sensor head positioned at two ends of the sensor adopts an optical fiber joint structure, the sensor body is composed of an optical fiber connection protection piece and two single-mode optical fibers, the optical fiber connection protection piece is provided with an optical fiber through hole, the two single-mode optical fibers are respectively inserted into the optical fiber through hole from two ends of the optical fiber connection protection piece, a gap of 50-100 mu m is formed between the end surfaces of the two single-mode optical fibers positioned in the optical fiber connection protection piece, and the gap and the end surfaces of the two single-mode optical fibers form an air cavity. The sensing head can adopt a commercial optical fiber connector, and the type of the connector can be selected according to a specific application scene so as to conveniently finish butt joint in specific application; the sensor body can be made of stainless steel capillary or flange plate to encapsulate the air cavity. The sensor has simple structure, simple manufacture, low cost and high disturbance detection sensitivity.
Description
Technical Field
The invention relates to the technical field of perimeter security and protection, and the sensor can be used for monitoring external invasion and disturbance.
Background
In recent years, due to the unique advantages of the optical fiber sensing technology, a great deal of research is carried out by domestic and foreign scholars and great results are obtained. These results are widely used in various fields and achieve good results. In general, techniques for external intrusion detection can be divided into two categories: one type is based on electrically implemented detection techniques, such as: infrared detection technology, video monitoring technology, electronic fence technology and the like. Such technologies rely heavily on the supply of electricity, which limits the application scenarios, such as in flammable and explosive locations, and in addition, the presence of electromagnetic interference may cause the technologies to fail to work properly. The other type is a detection technology realized based on optical fibers, and the technology effectively realizes the detection of external disturbance signals by utilizing the characteristic that the optical fibers can simultaneously sense and transmit signals. Optical fibers have many advantages such as: strong anti-interference capability, chemical corrosion resistance, good transmission confidentiality and the like. Clearly, detection techniques implemented using optical fibers would be a better choice. Wada K et al (Wada K, Narui H, Yamamoto D, et al, balanced polarization mail fiber, Sagnac interferometer amplification sensor, Opt. express,2011,19(22): 21467-21474). Because the structure is easy to generate reciprocal effect, the delay optical fiber is required to be connected in series or a half of the optical fiber ring is required to be shielded in practical application, and the application in outdoor places is influenced. The Mach-Zehnder type sensor structures proposed by P.Wei et al (P.Wei, X.Shan, X.Sun, Frequency response of distributed Fiber-Optical waveguide sensor based on non-balanced Mach-Zehnder interferometer, Optical Fiber Technology,2013,19:47-51) have polarization fading, require additional polarization tuning devices, and certainly increase the cost. Other scholars have fused different structures, e.g.
A.A.Chtcherbakov et al (A.A.Chtcherbakov, P.L.Swart, and S.J.Spammer.Mach-Zehnder and modified Sagnac distributed fiber-optical impact sensor [ J ]. appl.Opt.,1998,37(16): 3432-3437.) fuse a Sagnac-type sensing structure and a Mach-Zehnder-type structure. S.J.Spamer et al (S.J.Spamer, P.L.Swart and A.A.Chtcherbakov.Merged Sagnac-Michelson interferometer for distributed detection [ J ]. J.Lightw.Technol.,1997,15(6): 972-976.) fused a Michelson-type sensing structure with a Sagnac-type sensing structure. These fused structures become more complex and also increase costs.
Disclosure of Invention
The invention is provided on the basis of summarizing the advantages and the disadvantages of the prior art and aims to provide a single-core disturbance sensor with simple structure and low cost and a manufacturing method thereof. The disturbance sensor uses a single optical fiber, and the problems of pairing two optical fibers, polarization compensation and the like do not need to be considered.
In order to solve the technical problems, the single-core disturbance sensor provided by the invention comprises a sensor head and a sensor body, wherein the sensor head positioned at two ends of the sensor adopts an optical fiber joint structure, the sensor body is composed of an optical fiber connection protection piece and two single-mode optical fibers, the optical fiber connection protection piece is provided with an optical fiber through hole, the two single-mode optical fibers are respectively inserted into the optical fiber through hole from two ends of the optical fiber connection protection piece, and a gap of 50-100 m is formed between end faces of the two single-mode optical fibers positioned in the optical fiber connection protection piece.
Further, an embodiment of the single-core disturbance sensor provided by the present invention is that, the optical fiber connection protection member is a stainless steel capillary, the single-mode optical fiber has an outer diameter of 125m, and the stainless steel capillary has an inner diameter of 126 m; the end part of the stainless steel capillary tube is bonded with the two sections of single-mode optical fibers by glue.
The manufacturing method of the single-core disturbance sensor provided by the invention comprises the following steps:
cutting two sections of single-mode fibers by using a fiber cutter;
preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports; fixing the stainless steel capillary on a high-precision displacement table, inserting two cut single-mode fibers into the stainless steel capillary from two ends of the stainless steel capillary, and observing by using a microscope to ensure that the adjacent end faces of the two single-mode fibers are not contacted; fixing the single-mode optical fiber positioned outside the stainless steel capillary on supports on two sides of the high-precision displacement table, and controlling a gap of 50-100 m between the end surfaces of two sections of single-mode optical fibers by driving the single-mode optical fiber to move through an adjusting button;
and step three, gluing the stainless steel capillary and the single-mode optical fibers at two ends, and preparing the single-core disturbance sensor after the glue is solidified.
According to another embodiment of the single-core disturbance sensor, the optical fiber connection protection piece is a flange plate, and the two single-mode optical fibers are connected with the flange plate through jumper optical fiber connectors. The jumper type optical fiber connector adopts a flat-head optical fiber connector.
The invention provides a manufacturing method of the single-core disturbance sensor of the other embodiment, which comprises the following steps:
cutting two sections of single-mode fibers by using a fiber cutter;
preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports; fixing the flange plate on a high-precision displacement table, fixing a plain end optical fiber connector at one end of each cut two single-mode optical fibers, inserting the two single-mode optical fibers into the flange plate from one end of the plain end optical fiber connector, fixing the two single-mode optical fibers on supports at two sides of the high-precision displacement table, and controlling the distance between the two single-mode optical fibers to be 50-100 m by adjusting buttons on the supports;
and thirdly, fixing the positions of the single-mode optical fiber (1) and the drawing disc (5) by adopting a mechanical fixing piece.
Compared with the prior art, the invention has the beneficial effects that:
the single-core disturbance sensor designed by the invention has a simple structure and high disturbance detection sensitivity.
The method for manufacturing the single-core disturbance sensor adopts the common single-mode optical fiber, is beneficial to batch manufacturing of the sensor, improves the production efficiency while ensuring the consistency of the sensor, and reduces the manufacturing cost of the sensor.
Drawings
FIG. 1 is a schematic structural diagram of a single-core disturbance sensor embodiment 1 of the present invention;
FIG. 2 is a schematic structural diagram of a single-core disturbance sensor embodiment 2 of the present invention;
FIG. 3 is a schematic diagram of a disturbance detection system having a single-core disturbance sensor of the present invention;
fig. 4 shows a disturbance signal of external knocking on the optical cable detected by the sensor manufactured in embodiment 1 of the present invention.
In the figure:
1-single mode fiber 2-stainless steel capillary 3-glue bonding 4-flat head optical fiber joint
5-flange 6-light source 7-light adjustable attenuator 8-optical isolator
9 optical circulator 10-air cavity 11-photoelectric detector 12-data acquisition card
13-industrial control machine
Detailed Description
The technical solutions of the present invention are further described in detail with reference to the accompanying drawings and specific embodiments, which are only illustrative of the present invention and are not intended to limit the present invention.
The single-core disturbance sensor comprises a sensor head and a sensor body, wherein the sensor head positioned at two ends of the sensor adopts an optical fiber joint structure, the sensor body is composed of an optical fiber connection protection piece and two single-mode optical fibers, the optical fiber connection protection piece is provided with an optical fiber through hole, the two single-mode optical fibers are respectively inserted into the optical fiber through hole from two ends of the optical fiber connection protection piece, and a gap of 50-100 m is formed between the end faces of the two single-mode optical fibers positioned in the optical fiber connection protection piece.
Example 1: a single-core disturbance sensor.
As shown in fig. 1, in the single-core disturbance sensor of the present invention, the optical fiber connection protection member is a stainless steel capillary, the single-mode optical fiber has an outer diameter of 125m, and the stainless steel capillary has an inner diameter of 126 m; the end part of the stainless steel capillary tube is bonded with the two sections of single-mode optical fibers 1 by glue. The manufacturing method of the single-core disturbance sensor comprises the following steps:
firstly, cutting two sections of single-mode optical fibers 1 by using an optical fiber cutter; then, preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports; fixing the stainless steel capillary 2 on a high-precision displacement table, inserting the two cut single-mode optical fibers 1 into the stainless steel capillary 2 from two ends of the stainless steel capillary, and observing by using a microscope to ensure that the adjacent end faces of the two single-mode optical fibers 1 are not contacted; the single mode fiber located outside the stainless steel capillary 2 is fixed on the supports on two sides of the high-precision displacement table, the single mode fiber 1 is driven to move through the adjusting button, a gap of 50-100 m is formed between the end faces of the two sections of single mode fibers 1, and the gap and the end faces of the two single mode fibers form an air cavity. And finally, gluing the stainless steel capillary 2 and the single-mode optical fibers 1 at two ends, and preparing the single-core disturbance sensor after the glue is solidified.
When external disturbance acts on the sensing optical fiber, the length, the core diameter and the refractive index of the sensing optical fiber can be changed, and then the phase difference of two beams of light which are interfered is changed. The external disturbance signal acting on the sensing optical fiber can be determined by using a proper signal processing algorithm.
As shown in fig. 2, in the single-core disturbance sensor of the present invention, the optical fiber connection protection member is a flange 5, and two segments of single-mode optical fibers 1 are connected to the flange 5 by jumper optical fiber connectors. The jumper type optical fiber connector adopts a flat-head optical fiber connector 4. The manufacturing method of the single-core disturbance sensor comprises the following steps:
firstly, cutting two sections of single-mode optical fibers 1 by using an optical fiber cutter; then, preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports; fixing the flange plate 5 on a high-precision displacement table, fixing a plain end optical fiber connector 4 at one end of each of the two single-mode optical fibers 1 cut in the step I, inserting the two single-mode optical fibers 1 into the flange plate 5 from one end of the plain end optical fiber connector 4, fixing the two single-mode optical fibers 1 on supports at two sides of the high-precision displacement table, controlling the distance between the two single-mode optical fibers 1 to be 50-100 m by adjusting buttons on the supports, and forming an air cavity by the gap and the end faces of the two optical fibers; and finally, fixing the positions of the single-mode optical fiber 1 and the drawing disc 5 by adopting a mechanical fixing piece. The disturbance detection principle of this single-core disturbance sensor is similar to that of embodiment 1. The embodiment 2 of the invention is manufactured by utilizing the flange plate and the plain end jumper wire, and can effectively solve the problem of difficult optical fiber fixation.
In the single-core disturbance sensor, the sensor head selects a proper type of joint according to specific application requirements so as to conveniently finish butt joint of different application occasions; the sensor body can be realized by cutting a single mode fiber or a flat-end fiber joint; the optical fiber in the present invention is a single mode optical fiber.
Example 3: and (5) judging the disturbance of the single-core disturbance sensor.
The disturbance detection system of the single-core disturbance sensor is shown in fig. 3, wherein 6 is a light source, the central wavelength of the light source is around 1550nm, and the line width of the light source is about 50 Khz; 7 is a light adjustable attenuator for adjusting the output light power of the light source; 8, an optical isolator for eliminating the adverse effect of return light on the light source and ensuring that the light source can output with stable power; 9 is an optical circulator for enabling transmission of the output light of the light source to the air cavity 10, while for transmission of the return light of the air cavity 10 to the photodetector 11; 10 is an air cavity (formed by a gap between two single-mode fibers 1 and two fiber end faces) for realizing Fresnel reflection; 11 is a photoelectric detector for realizing the conversion between the interference light signal and the voltage signal; 12 is a data acquisition card: the photoelectric conversion device is used for acquiring a voltage signal after photoelectric conversion of the photoelectric detector; and 13, an industrial personal computer which processes the data acquired by the data acquisition card in real time and displays the alarm condition of the defense area in real time by utilizing a user interface which is designed and compiled in advance.
Light from the light source 6 passes through the optically adjustable attenuator 7, the optical isolator 8, and the optical circulator 9 and enters the air cavity 10. The reflected light generated by the air cavity 10 and the reflected light generated by the flat-end optical fiber joint 4 interfere with each other, and the intensity of the interference signal is
Wherein, I1、I2The light intensity of two beams of light which interfere with each other is delta phi, the delta phi is the phase difference between the two beams of light, when external disturbance acts on the optical fiber, the delta phi is changed, and the time domain shows that the waveform is changed more densely. For example, fig. 4 is a diagram of the collected signal of example 1 in which the optical fiber cable is tapped, and it is obvious that the waveform becomes more "dense" in the time domain when a disturbance occurs.
In conclusion, the sensing head in the sensor can adopt a commercial optical fiber connector, and the type of the connector can be selected according to a specific application scene so as to conveniently finish butt joint in specific application; the sensor body adopts a stainless steel capillary tube or a flange plate to encapsulate the air cavity. The sensor has simple structure, simple manufacture, low cost and high disturbance detection sensitivity.
While the present invention has been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are illustrative only and not restrictive, and various modifications which do not depart from the spirit of the present invention and which are intended to be covered by the claims of the present invention may be made by those skilled in the art.
Claims (6)
1. The utility model provides a single core disturbance sensor, includes sensor head and sensor body, its characterized in that: the sensor head that is located the sensor both ends adopts fiber joint structure, the sensor body comprises optic fibre connection protection piece and two sections single mode fiber (1), optic fibre connection protection piece is equipped with the optic fibre via hole, and two sections single mode fiber (1) are respectively certainly the both ends of optic fibre connection protection piece insert extremely in the optic fibre via hole, be located 50 ~ 100 mu m's clearance has between the terminal surface of two sections single mode fiber (1) in the optic fibre connection protection piece.
2. The single core disturbance sensor according to claim 1, wherein the optical fiber connection protector is a stainless steel capillary tube (2), the single mode optical fiber (1) has an outer diameter of 125 μm, and the stainless steel capillary tube (2) has an inner diameter of 126 μm; the end part of the stainless steel capillary tube (2) is bonded with the two sections of single-mode optical fibers (1) by glue.
3. A method for manufacturing a single core perturbation sensor according to claim 2, comprising the steps of:
firstly, cutting two sections of single-mode fibers (1) by using a fiber cutter;
preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports;
fixing the stainless steel capillary tube (2) on a high-precision displacement table, inserting two cut single-mode optical fibers (1) into the stainless steel capillary tube (2) from two ends of the stainless steel capillary tube, and observing by using a microscope to ensure that the adjacent end faces of the two single-mode optical fibers (1) are not contacted;
fixing the single-mode optical fiber positioned outside the stainless steel capillary tube (2) on supports on two sides of the high-precision displacement table, driving the single-mode optical fiber (1) to move through an adjusting button, and controlling a gap of 50-100 mu m between the end surfaces of the two sections of single-mode optical fibers (1);
and step three, gluing the stainless steel capillary tube (2) and the single-mode optical fibers (1) at the two ends, and preparing the single-core disturbance sensor after the glue is solidified.
4. The single-core disturbance sensor according to claim 1, wherein the optical fiber connection protection member is a flange plate (5), and two single-mode optical fibers (1) are connected with the flange plate (5) through jumper optical fiber joints.
5. The single core disturbance sensor according to claim 1, wherein the jumper fiber optic connector is a flat-head fiber optic connector (4).
6. A method for manufacturing a single core disturbance sensor according to claim 5, comprising the steps of:
firstly, cutting two sections of single-mode fibers (1) by using a fiber cutter;
preparing a high-precision displacement table, wherein supports are arranged on two sides of the high-precision displacement table, and micro-distance adjusting buttons are arranged on the supports;
fixing the flange plate (5) on a high-precision displacement table, fixing a flat-head optical fiber connector (4) at one end of each cut two single-mode optical fibers (1), inserting the two single-mode optical fibers (1) into the flange plate (5) from one end of the flat-head optical fiber connector (4), fixing the two single-mode optical fibers (1) on supports at two sides of the high-precision displacement table, and controlling the distance between the two single-mode optical fibers (1) to be 50-100 mu m by adjusting an adjusting button on the support;
and thirdly, fixing the positions of the single-mode optical fiber (1) and the drawing disc (5) by adopting a mechanical fixing piece.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911187652.XA CN111175899A (en) | 2019-11-28 | 2019-11-28 | Single-core disturbance sensor and manufacturing method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911187652.XA CN111175899A (en) | 2019-11-28 | 2019-11-28 | Single-core disturbance sensor and manufacturing method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111175899A true CN111175899A (en) | 2020-05-19 |
Family
ID=70653733
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911187652.XA Pending CN111175899A (en) | 2019-11-28 | 2019-11-28 | Single-core disturbance sensor and manufacturing method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111175899A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060233484A1 (en) * | 2005-03-24 | 2006-10-19 | Richard Van Neste | Adhesive-assembled fiber-optic interferometer |
| CN203606024U (en) * | 2013-12-05 | 2014-05-21 | 中国计量学院 | Micro vibration fiber sensor with capillary packaging |
| CN106124414A (en) * | 2016-08-24 | 2016-11-16 | 马鞍山市安工大工业技术研究院有限公司 | A kind of highly sensitive optical fiber EFPI sensor and preparation method thereof |
| CN107764441A (en) * | 2017-09-12 | 2018-03-06 | 天津大学 | Pressure sensor F P intracavitary residual pressure measuring systems and method |
| CN110174068A (en) * | 2019-05-23 | 2019-08-27 | 西安工业大学 | A kind of sensitizing type Fabry-perot optical fiber microcavity strain transducer and preparation method thereof |
-
2019
- 2019-11-28 CN CN201911187652.XA patent/CN111175899A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060233484A1 (en) * | 2005-03-24 | 2006-10-19 | Richard Van Neste | Adhesive-assembled fiber-optic interferometer |
| CN203606024U (en) * | 2013-12-05 | 2014-05-21 | 中国计量学院 | Micro vibration fiber sensor with capillary packaging |
| CN106124414A (en) * | 2016-08-24 | 2016-11-16 | 马鞍山市安工大工业技术研究院有限公司 | A kind of highly sensitive optical fiber EFPI sensor and preparation method thereof |
| CN107764441A (en) * | 2017-09-12 | 2018-03-06 | 天津大学 | Pressure sensor F P intracavitary residual pressure measuring systems and method |
| CN110174068A (en) * | 2019-05-23 | 2019-08-27 | 西安工业大学 | A kind of sensitizing type Fabry-perot optical fiber microcavity strain transducer and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 刘琨 等: "基于波长调制技术的内腔式气体传感研究", 《中国激光》 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102508337B (en) | Optical fiber fused taper-based intrinsic Fabry-Perot device and manufacturing method thereof | |
| CN205691170U (en) | A kind of air pressure and the Fibre Optical Sensor of temperature simultaneously measuring | |
| US4650281A (en) | Fiber optic magnetic field sensor | |
| CN207335782U (en) | A kind of high stability all -fiber magnetic field and temperature two parameter measurement sensing head | |
| CN204964060U (en) | Temperature sensing device based on optic fibre mach -Zehnder that receives a little interferes | |
| CN103884364A (en) | Optical fiber interferometric sensor based on cascade connection between tapered structure and spherical structure | |
| CN112414581B (en) | Temperature sensor based on multicore optic fibre | |
| CN105953958A (en) | All-silica fiber Fabry-Perot pressure sensor | |
| CN201181206Y (en) | Strain sensor based on porous microstructure optical fiber | |
| CN108957209B (en) | Automatic broken line detection device for communication optical fiber cable production | |
| CN108267241B (en) | High-sensitivity optical fiber temperature sensor based on hybrid double peanut knots | |
| CN108254101A (en) | A kind of polarization interference formula passive fiber temperature sensor | |
| CN111175899A (en) | Single-core disturbance sensor and manufacturing method thereof | |
| CN205785514U (en) | A kind of all-fiber power measuring system for high-capacity optical fiber laser | |
| CN209746025U (en) | Current measurement system based on double fiber bragg gratings | |
| CN201247073Y (en) | Distributed optical fiber sensor based on optical fiber cavity wane sway technology | |
| CN102364313A (en) | High-temperature sensing method based on optical fiber micro Michelson interference on spherical end face | |
| CN102081197A (en) | Wavelength division multiplexer | |
| CN104748772B (en) | Positioning optical fiber grating sensing device | |
| Xiao et al. | Absolute sapphire optical fiber sensor for high-temperature applications | |
| CN114184119A (en) | Low-cost repeatedly-produced polarization-maintaining optical fiber end surface Michelson interference sensor | |
| CN112082736B (en) | Polarization maintaining optical fiber ring polarization crosstalk bidirectional measuring device and method based on multifunctional optical switch | |
| CN201252545Y (en) | Optical fiber power monitor based on evanescent field | |
| CN207991710U (en) | A kind of polarization interference formula passive fiber temperature sensor | |
| CN115307567A (en) | Curvature sensor based on multi-core optical fiber tapering and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20200519 |