CN113686460A - Fiber grating temperature sensor and sensing device based on vernier effect - Google Patents
Fiber grating temperature sensor and sensing device based on vernier effect Download PDFInfo
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Abstract
The invention provides a fiber grating temperature sensor and a sensing device based on vernier effect; the fiber bragg grating temperature sensor comprises an optical fiber, a first region and a second region which are cascaded are arranged in the optical fiber, the first region is provided with two Bragg fiber bragg grating structures serving as resonant cavities so as to form an FBG-FP cavity, the second region is provided with two long-period fiber bragg grating structures so as to form a double long-period fiber bragg grating structure, and the FBG-FP cavity and the double long-period fiber bragg grating structure are cascaded to generate a vernier effect; the FBG-FP cavity and the long-period fiber grating structure generate a low-sensitivity structure and a high-sensitivity structure through at least two cascade connection modes; wherein the low-sensitivity structure is used as a cursor fixing part, and the high-sensitivity structure is used as a cursor sliding part. Compared with the traditional Mach-Zehnder interferometer, the dual LPFG structure is easier to realize, reduces the measurement error and has higher resolution.
Description
Technical Field
The invention relates to the technical field of sensors, in particular to a fiber grating temperature sensor and a sensing device based on a vernier effect.
Background
Since there is a higher requirement for the sensitivity of the optical fiber temperature sensor in some special application fields, researchers have begun to use the vernier effect as a sensitization means, and thus further apply the vernier effect to optical detection and achieve certain effect.
Various optical vernier structures have been proposed in the prior art, including: the cascade structure of FPI, MZI and FSI, etc., but usually the two filters have the same sensitivity, which is not good for the vernier effect.
This problem can be solved by combining two interferometers of different sensitivities using a low-sensitivity interferometer as the cursor-fixing part and a high-sensitivity interferometer as the cursor-sliding part, but the influence of the interferometer as a fixed scale still exists and can be amplified by the cursor effect. Thus, there still remains a solvable technical problem.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a fiber grating temperature sensor and a sensing device for the fiber grating temperature sensor.
In order to achieve the above object, in a first aspect of the present invention, a fiber grating temperature sensor based on a vernier effect is provided, where the fiber grating temperature sensor includes an optical fiber, and includes a first region and a second region that are cascaded, the first region is provided with two bragg fiber grating structures as a resonant cavity to form an FBG-FP cavity, the second region is provided with two long-period fiber grating structures to form a dual long-period fiber grating structure, and the FBG-FP cavity and the dual long-period fiber grating structure are cascaded to generate the vernier effect; the FBG-FP cavity and the long-period fiber grating structure generate a low-sensitivity structure and a high-sensitivity structure through at least two cascade connection modes; wherein the low-sensitivity structure is used as a cursor fixing part, and the high-sensitivity structure is used as a cursor sliding part.
In the embodiment of the invention, the two fiber bragg grating structures have consistent structural parameters and are separated by a preset distance to form the FBG-FP cavity.
In the embodiment of the present invention, the two fiber bragg grating structures are a first fiber bragg grating structure and a second fiber bragg grating structure, the grating length of the first fiber bragg grating structure and the grating length of the second fiber bragg grating structure are 1000 μm, the grating period is 0.5358 μm, the refractive index modulation depth is 0.00015, and the length of the first fiber bragg grating structure and the length of the second fiber bragg grating structure are 3000 μm.
In the embodiment of the invention, the two long-period fiber grating structures are a first long-period fiber grating and a second long-period fiber grating, the grating length of the first long-period fiber grating and the grating length of the second long-period fiber grating are 50000 mu m, the grating period is 670.70882 mu m, the refractive index modulation depth is 0.00015, and the length of the first long-period fiber grating and the length of the second long-period fiber grating are 50000 mu m.
In an embodiment of the invention, the optical fiber comprises any one of: single mode fibers, multimode fibers, photonic crystal fibers.
In the embodiment of the invention, the optical fiber is a single-mode optical fiber, the diameter of a core is 4.15 mu m, the refractive index is 1.4492 mu m, the diameter of a cladding of the optical fiber is 58.35 mu m, and the refractive index is 1.4403 mu m.
In a second aspect of the present application, there is also provided a fiber grating temperature sensing device based on vernier effect, including the fiber grating temperature sensor as described above, the fiber grating temperature sensing device further includes: the device comprises an optical signal emitter, an optical isolator and a spectrometer; the optical signal transmitter is connected with the input end of the optical isolator, the output end of the optical isolator is connected with the input end of the fiber grating temperature sensor, and the output end of the fiber grating temperature sensor is connected with the spectrometer.
In the embodiment of the invention, the optical signal emitted by the optical signal emitter is a continuous spectrum laser source without mutation, and the wavelength of the continuous spectrum laser source is 800-1800 nm.
In the embodiment of the invention, the spectrometer is used for detecting the light intensity with the wavelength ranging from 800nm to 1800nm, and the detection sensitivity is less than 1 nm.
In an embodiment of the present invention, the optical signal transmitter emits an incident optical signal at 1550 nm.
Through above-mentioned technical scheme, possess following beneficial effect: the fiber grating temperature sensor provided by the embodiment of the invention adopts the structures with different sensitivities to carry out cascade combination, so that the sensor has higher sensitivity to temperature by generating a vernier effect; the fiber grating temperature sensor is designed with fiber grating structure parameters, such as: the length of the fiber grating, the grating period and the refractive index modulation depth can be accurately controlled, and the design can be flexible, and the sensing sensitivity and the resolution can be adjusted; the fiber grating temperature sensor is prepared by optical fibers, and has the advantages of low cost, simple preparation and the like; the FBG-FP cavity prepared by the fiber bragg grating temperature sensor by adopting the fiber bragg grating technology not only retains the advantages of the traditional FP cavity, but also has the advantages of high physical strength and wide measurement range; compared with the traditional Mach-Zehnder interferometer, the dual LPFG structure is easier to realize, reduces the measurement error and has higher resolution.
Additional features and advantages of embodiments of the invention will be set forth in the detailed description which follows.
Drawings
The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention without limiting the embodiments of the invention. In the drawings:
FIG. 1 is a schematic structural diagram of a fiber grating temperature sensor based on vernier effect according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a fiber grating temperature sensing device based on vernier effect according to an embodiment of the present invention;
FIG. 3 is a transmitted light spectrum as illustrated in an example of the present invention; and
FIG. 4 is a graph of an exemplary reflectance spectrum according to an embodiment of the present invention.
Description of the reference numerals
100. A fiber grating temperature sensor; 30. An optical fiber;
10. a fiber grating Fabry-Perot cavity; 20. A dual long period fiber grating structure;
101. a first fiber Bragg grating structure; 102. A second fiber Bragg grating structure;
201. a first long-period fiber grating 201; 202. A second long-period fiber grating;
1. an optical signal transmitter; 2. An optical isolator;
3(100), fiber grating temperature sensor; 4. A spectrometer;
5. and (4) an upper computer.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating embodiments of the invention, are given by way of illustration and explanation only, not limitation.
It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.
In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "or" appearing throughout is meant to encompass three juxtapositions, exemplified by "a or B" and including either a disposition or B disposition, or both a and B satisfied disposition. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.
For a better understanding of the present solution, the present solution is described in terms of the following terminology to be devised.
Fiber grating: the forming mode is mainly that various lasers are used to enable the optical fiber to generate axial refractive index periodic variation, so that a permanent spatial phase grating is formed, the effect is essentially to form a (transmission or reflection) filter or a reflector in the fiber core, and the guided mode with determined frequency/wavelength is reflected, the principle is similar to a multilayer reflection increasing film, the filtering wavelength is called Bragg wavelength, the Bragg wavelength is equal to the effective refractive index of the position where the grating is located multiplied by the geometric period of the grating under the determined condition, and the effective refractive index and the grating period can change along with the temperature and stress state, and the application of the optical fiber grating to stress and temperature sensing is also the basis.
[ EXAMPLES one ]
Referring to fig. 1, fig. 1 is a schematic structural diagram of a fiber grating temperature sensor 100 based on a vernier effect according to an embodiment of the present invention.
The fiber bragg grating temperature sensor 100 includes at least one optical fiber 30, a section of the optical fiber 30 of the grating temperature sensor is cut out, for example, a first fiber bragg grating structure 101 and a second fiber bragg grating structure 102 are written on the section of the optical fiber 30, and the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 are arranged at a certain preset distance, so that the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 form an FBG-FP cavity 10(FBG-FP cavity: fiber bragg grating fabry-perot cavity, the same applies below) so that an optical signal can be freely transmitted therebetween.
Further, in the direction along the optical path on the same optical fiber 30, the first long-period fiber grating 201 and the second long-period fiber grating 202 are also written on the section of optical fiber 30, and the first long-period fiber grating 201 and the second long-period fiber grating 202 are equally spaced by a preset distance, so as to form the dual long-period fiber grating structure 20.
In order to realize the vernier effect, the fiber bragg grating Fabry-Perot cavity 10 and the double long-period fiber bragg grating structure 20 are combined into two structures with different sensitivities in different cascading modes so as to generate the vernier effect;
it is understood that the vernier effect is due to the physical phenomenon in the form of a scale existing in optics, for example, the reflection or transmission spectrum of a broad spectrum light source after passing through a fabry-perot cavity etalon is a comb spectrum, such as the reflection spectrum of a bragg sampling grating.
The peak pitch of the comb spectrum can be adjusted by adjusting the width of the optical signal or the cavity length of the fiber bragg grating fabry-perot cavity 10 and the double long-period fiber bragg grating structure 20, so that after the optical signal passes through the fiber bragg grating fabry-perot cavity 10 and the double long-period fiber bragg grating structure 20, two spectra with different peak pitches can be obtained, and the optical vernier effect can be formed by mutually influencing the spectra, assuming that one of the cavity structures (one of the fiber grating fabry-perot cavity 10 and the dual long-period fiber grating structure 20) receives external environmental influences, such as temperature, pressure and strain, the spectrum of the device slightly shifts under the condition of keeping the peak distance, the generated micro displacement can be amplified and read by detecting the initially aligned spectrum and the current spectrum, therefore, sensing is realized, a larger measuring range can be kept, and the measuring sensitivity can be improved.
Further, the cascade connection mode mentioned above may be, for example, a cyclic cascade connection, a cascade amplifier or an interface, after the cascade connection, the fiber grating fabry-perot cavity 10 and the dual long period fiber grating structure 20 may change their sensitivity according to the measurement environment and the designed structural parameters, wherein the low-sensitivity structure is used as the cursor fixing portion, and the high-sensitivity structure is used as the cursor sliding portion.
Furthermore, when the fiber bragg grating fabry-perot cavity 10 is designed, it is required to ensure that the structural parameters of the two fiber bragg gratings (i.e., the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102) are consistent and are separated by a preset first distance (the first distance is obtained by experimentally allocating the distance according to the size structure of the optical fiber), and the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 are arranged in a layout manner to form an FBG-FP cavity.
Meanwhile, when the dual long-period fiber grating structure 20 is designed, it is required to ensure that the parameters of the two long-period fiber grating structures (i.e., the first long-period fiber grating 201 and the second long-period fiber grating 202) are consistent and are separated by a preset second distance, which is determined according to the size of the optical fiber, and then the two long-period fiber grating structures are cascaded to form the dual long-period fiber grating structure.
Wherein, the above mentioned "structural parameters" refer to the length, width, depth and other dimensional parameters of the grating structure.
It is understood that in the embodiments of the present invention, the specific shape of the optical fiber mentioned above may not be limited, and may be various, and different types of optical fibers may be selected according to the measured environmental conditions and the measured temperature range, and the material and composition of the optical fiber may be changed, and different shapes may be designed, and the optical fiber is specially designed according to the actual situation.
Further, the above-mentioned optical fiber may include: single mode fibers, multimode fibers, photonic crystal fibers, and the like.
In a specific embodiment, structures in the fiber grating temperature sensor 100 may be written in the form of an ultraviolet lithography technique, and an ultraviolet light source is used to transfer the cavity structure to the optical fiber.
Uv lithography is a common technique used by those skilled in the art, and is not overly elaborated.
In a specific embodiment, the grating length of the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 is 1000 μm, the grating period is 0.5358 μm, the refractive index modulation depth is 0.00015, and the length of the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 is 3000 μm, so as to form the fiber bragg grating fabry-perot cavity 10; the grating length of the first long-period fiber grating 10 and the second long-period fiber grating 202 is 50000 μm, the grating period is 670.70882 μm, the refractive index modulation depth is 0.00015, and the length of the first long-period fiber grating 10 and the second long-period fiber grating 202 is 50000 μm, thereby forming the dual long-period fiber grating structure 20.
It should be understood by those skilled in the art that the above data are analyzed and simple modifications may be made to the above data, such as modulating the grating period of the first fiber bragg grating structure 101 and the second fiber bragg grating structure 102 within plus or minus 0.05 μm, and still fall within the scope of the present invention,
in the cascade mode of the fiber bragg grating temperature sensor 100, the fiber bragg grating fabry-perot cavity 10 with high sensitivity can be used as a cursor sliding part, the double long-period fiber bragg grating structure 20 with low sensitivity is used as a cursor fixing part, and a cursor effect is generated through cascade.
After the fiber bragg grating temperature sensor is placed in the air, the temperature change around the sensor is subjected to temperature adjustment by adopting a temperature control device. In the experiment, the temperature change is between-20 ℃ and 100 ℃, the temperature change range of-20 ℃ to 100 ℃ is recorded, and a transmission spectrogram and a reflection spectrogram of the sensor are obtained by a spectrometer and are shown in figures 3 and 4 respectively. It is evident that the temperature sensitivity and measurement range of the temperature sensor of the embodiment of the present invention are further improved compared to the FBG-FP cavity structure alone and the dual LPFG structure.
In summary, the embodiment of the present invention, through the above technical solution, has the following beneficial effects: the fiber grating temperature sensor provided by the embodiment of the invention adopts the structures with different sensitivities to carry out cascade combination, so that the sensor has higher sensitivity to temperature by generating a vernier effect; the fiber grating temperature sensor 100 is designed with fiber grating structure parameters, such as: the length of the fiber grating, the grating period and the refractive index modulation depth can be accurately controlled, and the design can be flexible, and the sensing sensitivity and the resolution can be adjusted; the fiber grating temperature sensor 100 is made of optical fibers, and has the advantages of low cost, simplicity in preparation and the like; the FBG-FP cavity prepared by the fiber bragg grating temperature sensor 100 by adopting the fiber bragg grating technology not only retains the advantages of the traditional FP cavity, but also has the advantages of high physical strength and wide measurement range; compared with the traditional Mach-Zehnder interferometer, the dual LPFG structure is easier to realize, reduces the measurement error and has higher resolution.
[ example two ]
Referring to fig. 2, fig. 2 is a schematic structural diagram of a fiber grating temperature sensing device based on a vernier effect according to an embodiment of the present invention; the embodiment provides a fiber grating temperature sensing device based on vernier effect, which comprises an optical signal emitter 1, an optical isolator 2, a fiber grating temperature sensor 3 (which is clear and continuous in reference number and is replaced by the fiber grating temperature sensor 3 as the fiber grating temperature sensor 100), a spectrometer 4 and an upper computer 5; the signal emitter 1, the optical isolator 2, the fiber bragg grating temperature sensor 3, the spectrometer 4 and the upper computer 5 are connected in sequence according to a light path.
Further, the optical signal transmitter 1 can output incident light, and the incident light gets into the fiber grating temperature sensor 3 via the incident light of optical isolator 2 after optical isolator 2, and the incident light can take place to interfere when passing through fiber grating temperature sensor 3, and the incident light after 3 interference of fiber grating temperature sensor gets into spectrum appearance 4, and spectrum appearance 4 is connected to host computer 5, and the last analysis corresponds data in host computer 5.
The upper computer 5 may be a PC terminal, a mobile phone, a tablet, or a microcomputer.
Referring to fig. 2, the incident light output from the optical signal transmitter 1 is adjusted and controlled many times, in this example, the output wavelength of the incident light used by the optical signal transmitter 1 is 1550nm, and the detection wavelength range of the spectrometer 4 is 1545 to 1555nm, in this detection experiment, the optical fiber in the fiber grating temperature sensor 3 is a conventional single-mode optical fiber, the core diameter of which is 4.15 μm, the refractive index of which is 1.4492 μm, the cladding diameter of which is 58.35 μm, and the refractive index of which is 1.4403 μm.
When the external temperature is simulated to change through the temperature controller, the interference output signal of the fiber grating temperature sensor 3 is caused to change correspondingly by acting on the fiber grating temperature sensor in a certain form, and the change parameter of the external temperature can be obtained by analyzing the data of the spectrometer 4, so that the temperature sensing is realized. By adjusting and controlling the signal light of the optical signal transmitter 1 in different wavelength ranges and the structural parameters of the FPG-FP cavity and the double-long period fiber grating in the fiber grating temperature sensor 3, the temperature measurement under different environments can be realized, and meanwhile, the sensitivity of the sensor to the temperature measurement under different environments can be further improved.
According to different environments where the temperature is measured and different incident light wavelength range requirements required by fiber grating design, the optical signal transmitter 1 can be a continuous spectrum laser light source with continuously changing wavelength in the range of 800-1800 nm and without mutation, the spectrometer 4 can be a spectrometer for detecting light intensity in the range of 800-1800 nm, and the detection sensitivity is less than 1 nm.
Referring to fig. 1 and fig. 2, the working principle of the sensing device according to the embodiment of the present invention is as follows: the 1550nm incident light signal emitted by the light signal emitter 1 enters the optical isolator 2 through the single mode fiber, the optical isolator 2 can reduce the bad influence of the reflected light generated by the Bragg grating on the stability of the spectral output power of the light source to a great extent, after the incident light passes through the optical isolator 2, enters the fiber bragg grating temperature sensor 3, after the incident light passes through the first fiber bragg grating structure 101, a part of light is reflected back, the other part of light is transmitted, while the light transmitted through the bragg fiber grating structure 10 continues to propagate forward to the second bragg fiber grating structure 102, some light is still transmitted, the light reflected by the second bragg fiber grating structure 102 interferes in the fiber grating fabry-perot cavity 10 formed by the first bragg fiber grating structure 101 and the second bragg fiber grating structure 102;
further, when the transmitted light passing through the second bragg fiber grating structure 102 continues to propagate forward and meets the first long-period fiber grating 201, part of energy is coupled into the cladding and continues to be transmitted forward, when the transmitted light meets the second long-period fiber grating 202, part of the energy transmitted in the cladding is consumed, the rest energy is coupled into the fiber core again, interference fringes are formed in the transmission spectrum when the coupling is carried out again, which is equivalent to a Mach-Zehnder effect (Mach-Zehnder effect: Mach-Zehnder effect, refer to a Mach-Zehnder interferometer), the optical signal passing through the fiber grating temperature sensor 3 enters the spectrometer 4, the spectrometer 4 is connected to the upper computer 5, and finally, temperature data are analyzed in the upper computer.
To sum up, the embodiment of the present invention may derive a fiber grating temperature sensing device based on the fiber grating temperature sensor 3, and the device combines the original devices such as the optical signal emitter, the optical isolator, and the spectrometer on the basis of the fiber grating temperature sensor.
It should also be understood by those skilled in the art that if the fiber grating temperature sensor or the fiber grating temperature sensor provided by the present invention is simply changed, the above methods are added with functions to be combined, or the device is replaced, such as the replacement of model materials, the replacement of use environment, the simple replacement of the position relationship of the components, etc., of the components; or the products formed by the components are integrally arranged; or a detachable design; it is within the scope of the present invention to replace the methods and apparatus of the present invention with any method/apparatus/device that combines the components to form a method/apparatus/device with specific functionality.
It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.
The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.
Claims (10)
1. The fiber bragg grating temperature sensor based on the vernier effect is characterized by comprising an optical fiber, wherein a first region and a second region which are cascaded are arranged in the optical fiber, the first region is provided with two Bragg fiber bragg grating structures serving as resonant cavities so as to form an FBG-FP (fiber Bragg grating) -cavity, the second region is provided with two long-period fiber bragg grating structures so as to form a double long-period fiber bragg grating-structure, and the FBG-FP-cavity and the double long-period fiber bragg grating-structure are cascaded to generate the vernier effect; the FBG-FP cavity and the long-period fiber grating structure generate a low-sensitivity structure and a high-sensitivity structure through at least two cascade connection modes; wherein the low-sensitivity structure serves as a cursor fixing part and the high-sensitivity structure serves as a cursor sliding part.
2. The vernier effect based fiber grating temperature sensor as claimed in claim 1, wherein the two fiber bragg grating structures have a same structural parameter and are spaced apart by a predetermined distance to form an FBG-FP cavity.
3. The vernier effect based fiber grating temperature sensor as claimed in claim 1, wherein the two fiber bragg grating structures are a first fiber bragg grating structure and a second fiber bragg grating structure, the grating length of the first fiber bragg grating structure and the second fiber bragg grating structure is 1000 μm, the grating period is 0.5358 μm, the refractive index modulation depth is 0.00015, and the length of the first fiber bragg grating structure and the second fiber bragg grating structure is 3000 μm.
4. The vernier effect based fiber grating temperature sensor as claimed in claim 1, wherein the two long period fiber grating structures are a first long period fiber grating and a second long period fiber grating, the grating length of the first long period fiber grating and the second long period fiber grating is 50000 μm, the grating period is 670.70882 μm, the refractive index modulation depth is 0.00015, and the length of the first long period fiber grating and the second long period fiber grating is 50000 μm.
5. The vernier effect based fiber grating temperature sensor of any one of claims 1 to 4, wherein the optical fiber comprises any one of: single mode optical fibers, multimode optical fibers, or photonic crystal fibers.
6. The vernier effect based fiber grating temperature sensor of claim 5, wherein the optical fiber is a single mode fiber having a core diameter of 4.15 μm and a refractive index of 1.4492 μm, and a fiber cladding diameter of 58.35 μm and a refractive index of 1.4403 μm.
7. A vernier effect based fiber grating temperature sensing apparatus, comprising the vernier effect based fiber grating temperature sensor according to any one of claims 1 to 6, the fiber grating temperature sensing apparatus further comprising:
the device comprises an optical signal emitter, an optical isolator and a spectrometer;
wherein, optical signal transmitter with optical isolator's input is connected, optical isolator's output with fiber grating temperature sensor's input is connected, fiber grating temperature sensor's output with the spectrum appearance is connected.
8. The vernier effect based fiber grating temperature sensing apparatus as claimed in claim 7, wherein the optical signal emitted by the optical signal emitter is a continuous spectrum laser light source with a wavelength of 800 to 1800nm without abrupt change.
9. The vernier effect based fiber grating temperature sensing apparatus of claim 7, wherein the spectrometer is a spectrometer for detecting light intensity in the wavelength range of 800 to 1800nm, and the detection sensitivity is less than 1 nm.
10. The vernier effect based fiber grating temperature sensing apparatus of claim 7, wherein the optical signal emitter emits 1550nm of incident optical signals.
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102096151A (en) * | 2010-12-15 | 2011-06-15 | 北京理工大学 | Method for manufacturing fiber Mach-Zehnder interferometer |
| CN102162753A (en) * | 2010-12-09 | 2011-08-24 | 无锡成电光纤传感科技有限公司 | Sensor structure for simultaneously measuring temperature and strain of long period fiber gratings (LPFGs) |
| CN105716755A (en) * | 2016-01-25 | 2016-06-29 | 西南交通大学 | Sensitivity enhanced sensor based on Loyt-Sagnac interferometer |
| CN108195485A (en) * | 2017-12-29 | 2018-06-22 | 北京信息科技大学 | Temperature and the biparameter sensor of strain and preparation method thereof are measured based on LPFG and MZ cascades |
| CN108254018A (en) * | 2017-12-29 | 2018-07-06 | 北京信息科技大学 | The preparation method of stress and temperature biparameter sensor based on LPFG cascades FBG |
| CN108279029A (en) * | 2017-12-29 | 2018-07-13 | 北京信息科技大学 | Two-parameter fibre optical sensor and preparation method thereof based on LPFG and FBG cascade structures |
| CN207937363U (en) * | 2018-02-11 | 2018-10-02 | 鞍山峰澜科技有限公司 | It is a kind of based on cursor effect can simultaneously measuring temperature and hydrogen fibre optical sensor |
| CN109323776A (en) * | 2018-11-07 | 2019-02-12 | 哈尔滨工程大学 | Fibre optic temperature sensor and preparation method thereof based on liquid crystal Fabry-Bo Luo resonant cavity |
| CN109580036A (en) * | 2019-01-22 | 2019-04-05 | 北京信息科技大学 | FP temperature sensor and preparation method thereof based on photonic crystal fiber FBG |
| CN109974759A (en) * | 2019-04-23 | 2019-07-05 | 中国计量大学 | With cascade Fabry-Perot-type cavity sensor in optical fiber cable of the femtosecond laser induction based on cursor effect |
| CN111323059A (en) * | 2018-12-17 | 2020-06-23 | 中国科学院深圳先进技术研究院 | Sensing device based on fiber Bragg grating Fabry-Perot cavity |
| CN216349216U (en) * | 2021-03-17 | 2022-04-19 | 广东工业大学 | Fiber grating temperature sensor and temperature sensing device based on vernier effect |
-
2021
- 2021-08-02 CN CN202110882675.3A patent/CN113686460B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102162753A (en) * | 2010-12-09 | 2011-08-24 | 无锡成电光纤传感科技有限公司 | Sensor structure for simultaneously measuring temperature and strain of long period fiber gratings (LPFGs) |
| CN102096151A (en) * | 2010-12-15 | 2011-06-15 | 北京理工大学 | Method for manufacturing fiber Mach-Zehnder interferometer |
| CN105716755A (en) * | 2016-01-25 | 2016-06-29 | 西南交通大学 | Sensitivity enhanced sensor based on Loyt-Sagnac interferometer |
| CN108195485A (en) * | 2017-12-29 | 2018-06-22 | 北京信息科技大学 | Temperature and the biparameter sensor of strain and preparation method thereof are measured based on LPFG and MZ cascades |
| CN108254018A (en) * | 2017-12-29 | 2018-07-06 | 北京信息科技大学 | The preparation method of stress and temperature biparameter sensor based on LPFG cascades FBG |
| CN108279029A (en) * | 2017-12-29 | 2018-07-13 | 北京信息科技大学 | Two-parameter fibre optical sensor and preparation method thereof based on LPFG and FBG cascade structures |
| CN207937363U (en) * | 2018-02-11 | 2018-10-02 | 鞍山峰澜科技有限公司 | It is a kind of based on cursor effect can simultaneously measuring temperature and hydrogen fibre optical sensor |
| CN109323776A (en) * | 2018-11-07 | 2019-02-12 | 哈尔滨工程大学 | Fibre optic temperature sensor and preparation method thereof based on liquid crystal Fabry-Bo Luo resonant cavity |
| CN111323059A (en) * | 2018-12-17 | 2020-06-23 | 中国科学院深圳先进技术研究院 | Sensing device based on fiber Bragg grating Fabry-Perot cavity |
| CN109580036A (en) * | 2019-01-22 | 2019-04-05 | 北京信息科技大学 | FP temperature sensor and preparation method thereof based on photonic crystal fiber FBG |
| CN109974759A (en) * | 2019-04-23 | 2019-07-05 | 中国计量大学 | With cascade Fabry-Perot-type cavity sensor in optical fiber cable of the femtosecond laser induction based on cursor effect |
| CN216349216U (en) * | 2021-03-17 | 2022-04-19 | 广东工业大学 | Fiber grating temperature sensor and temperature sensing device based on vernier effect |
Non-Patent Citations (2)
| Title |
|---|
| 周豫;周雪芳;樊冰;李曾阳;胡淼;毕美华;杨国伟;王天枢;: "基于Vernier效应的光纤温度传感特性研究", 光电子・激光 * |
| 赵春柳;李嘉丽;徐贲;龚华平;王东宁;: "光纤微腔法布里-珀罗干涉传感器研究进展", 应用科学学报 * |
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