CN113804649A - Single-frequency thulium-doped inner cavity mixed gas component identification and concentration detection optical fiber sensing system - Google Patents
Single-frequency thulium-doped inner cavity mixed gas component identification and concentration detection optical fiber sensing system Download PDFInfo
- Publication number
- CN113804649A CN113804649A CN202111025021.5A CN202111025021A CN113804649A CN 113804649 A CN113804649 A CN 113804649A CN 202111025021 A CN202111025021 A CN 202111025021A CN 113804649 A CN113804649 A CN 113804649A
- Authority
- CN
- China
- Prior art keywords
- optical fiber
- thulium
- laser
- doped
- mixed gas
- 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.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/03—Cuvette constructions
- G01N21/0303—Optical path conditioning in cuvettes, e.g. windows; adapted optical elements or systems; path modifying or adjustment
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/255—Details, e.g. use of specially adapted sources, lighting or optical systems
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06708—Constructional details of the fibre, e.g. compositions, cross-section, shape or tapering
- H01S3/06716—Fibre compositions or doping with active elements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/06791—Fibre ring lasers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/094042—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a fibre laser
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Plasma & Fusion (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
本发明公开了一种单频掺铥内腔混合气体组分识别浓度检测光纤传感系统，所述系统包括：分布反馈布拉格半导体激光器输出的1570nm激光，经掺铒光纤放大器放大后作为泵浦光，通过1570/2000nm波分复用器耦合进入环形腔掺铥光纤激光器中，所述单向光纤隔离器用于保证2000nm波段激光在此环形腔掺铥光纤激光器中逆时针往返传输，所述2000nm波段激光每次经过所述气室时，均与内部的待测气体充分地相互作用，最终从输出耦合器输出携带气体组成成分和浓度双重信息的激光。本发明实现了上述气体甚至更多种类气体的组分精准识别和浓度检测，提高系统检测的灵敏度和更低气体浓度的测量。
The invention discloses a single-frequency thulium-doped inner cavity mixed gas component identification and concentration detection optical fiber sensing system. The system comprises: a 1570 nm laser output by a distributed feedback Bragg semiconductor laser, amplified by an erbium-doped fiber amplifier and used as pump light , and is coupled into the ring cavity thulium-doped fiber laser through a 1570/2000nm wavelength division multiplexer. The unidirectional fiber isolator is used to ensure that the 2000nm band laser is transmitted back and forth counterclockwise in this ring cavity thulium-doped fiber laser. The 2000nm band Each time the laser passes through the gas chamber, it fully interacts with the gas to be measured inside, and finally outputs the laser carrying dual information of gas composition and concentration from the output coupler. The present invention realizes the accurate identification and concentration detection of the above-mentioned gases and even more kinds of gases, improves the sensitivity of the system detection and the measurement of lower gas concentrations.
Description
Technical Field
The invention relates to the field of optical fiber sensing detection, in particular to a single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system.
Background
The optical fiber gas sensor has the advantages of strong anti-electromagnetic interference capability, high reliability, convenience for networking remote detection and the like, so that the optical fiber gas sensor is widely applied to the detection of toxic and harmful gases in the industries of environmental management, chemical production, power and electricity and the like. In the intelligent home, analysis of dangerous gas can be realized through a gas concentration sensor, so that a targeted control strategy can be adopted, and the method is also an important link for maintaining the life safety of the home and eliminating dangers in an unforeseen period.
The traditional optical fiber gas sensing system focuses on the concentration detection of single gas, so that the repeated utilization rate of the system is reduced; and the traditional optical fiber gas sensing system is mainly concentrated on a 1.5 mu m wave band, and the absorption intensity of gas to the wave band is relatively small, so that the sensitivity is still improved. For multi-component mixed gas detection, the interval between gas absorption peaks is an important factor influencing the identification accuracy, and the traditional optical fiber gas sensing system adopts a broadband light source or a MHz light source, so that the spectral width of the traditional optical fiber gas sensing system cannot meet the requirement of accurately identifying the gas with the closer interval of the absorption peaks, the resolution of the system for identifying different gases is severely limited, and the error of gas component identification is greatly increased. The narrow-linewidth fiber laser, especially the single-frequency fiber laser, can greatly narrow the linewidth of the laser output by the light source, the spectral width can reach below 1kHz, the interval between any absorption peaks can be effectively distinguished, and the identification resolution of different gas absorption peaks is improved.
Disclosure of Invention
The invention provides a single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system, which aims at CO2、NH3、CH4、H2S、O3And halogen hydrides such as NO, HBr and HCl, and gases such as water vapor, to realize the accurate component identification and concentration detection of the above gases and even more gases, to improve the sensitivity of system detection and the measurement of lower gas concentration, as described in detail below:
a single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system, the system includes: the optical fiber laser comprises an annular cavity thulium-doped optical fiber laser consisting of an 1570/2000nm wavelength division multiplexer, a first thulium-doped optical fiber, a one-way optical fiber isolator, a single-mode optical fiber with the fiber core/cladding diameter of 10/125 mu m, an air chamber, an optical fiber circulator, a second thulium-doped optical fiber, a plurality of optical fiber Bragg gratings, a polarization controller, an output coupler and an electric control adjustable F-P filter, and further comprises a monitoring device consisting of a spectrum analyzer and a scanning F-P interferometer;
1570nm laser of distributed feedback Bragg semiconductor laser output, as the pump light after erbium-doped fiber amplifier enlargies, get into annular chamber through 1570/2000nm wavelength division multiplexer coupling and mix in the thulium fiber laser, one-way fiber isolator is used for guaranteeing that 2000nm wave band laser is anticlockwise round trip transmission in this annular chamber mixes thulium fiber laser, 2000nm wave band laser is at every turn through during the air chamber, all interact fully with inside gaseous the awaiting measuring, finally carry the laser of gaseous composition and concentration dual information from output coupler output.
Wherein, the system also comprises a monitoring device which consists of a spectrum analyzer and a scanning type F-P interferometer. The electric control adjustable F-P filter is used for tuning the output wavelength, and when the current channel is in a working state, the identification of the gas type is completed through the automatic switching of the channel.
Further, when the concentration of the mixed gas is detected, the second thulium-doped optical fiber is used as a saturable absorber, the line width of the output signal light is narrowed, and the identification degree and the concentration detection sensitivity of the mixed gas are improved by utilizing the narrow line width characteristic.
In one implementation mode, a plurality of fiber Bragg gratings and an electrically-controlled adjustable F-P filter are used as frequency selection devices, the resonance absorption peak value of gas in a 2 mu m wave band is determined according to an HITRAN database, and the transmission wavelength of each fiber Bragg grating is selected to be in one-to-one correspondence with the resonance absorption peak values of different gases.
The scanning type F-P interferometer is used for monitoring the longitudinal mode running state of the output signal light; the spectrum analyzer is used for monitoring the spectrum of the output laser,
by analyzing the spectrogram of the output laser, the gas composition and corresponding concentration are obtained simultaneously: the composition of the detectable gas is obtained by analyzing whether the central wavelength intensity of the reflected light changes, so that the identification of the components is realized; the absorption intensity of the detected gas is obtained by analyzing the variation of the central wavelength intensity of the reflected light, so that the detection of the gas concentration is realized, and the simultaneous sensing of the component and the concentration of the mixed gas is realized.
In one embodiment, the fiber circulator connects a number of fiber bragg gratings corresponding to different gas absorption peak wavelengths into the ring cavity thulium doped fiber laser.
Further, the system can be used to achieve highly sensitive detection of halogen hydride and gas concentrations.
The technical scheme provided by the invention has the beneficial effects that:
1. the invention realizes full optical fiber, effectively reduces the volume of the gas sensing device, reduces the complexity of the system and improves the structural stability of the device;
2. the invention can not only realize the accurate identification of the components of the mixed gas, but also achieve the purpose of detecting the gas concentration, has good market prospect and simple realization mode;
3. the invention has good technical transformation base and is expected to be widely applied to monitoring the components of atmospheric environment gas such as water vapor, carbon dioxide, carbon monoxide, ozone and the like; the invention realizes wide social benefits.
Drawings
FIG. 1 is a schematic structural diagram of a single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system;
FIG. 2 is a schematic diagram of reflection spectra corresponding to mixed gases with different concentrations.
In the drawings, the components represented by the respective reference numerals are listed below:
1: 1570nm distributed feedback Bragg semiconductor laser; 2: an erbium-doped fiber amplifier;
3: 1570/2000nm wavelength division multiplexer; 4: a first thulium doped optical fiber;
5: a unidirectional fiber isolator; 6: a single mode optical fiber;
7: an air chamber; 8: a three-port fiber optic circulator;
9: a second thulium doped optical fiber; 101: a first fiber Bragg grating;
102: a second fiber Bragg grating; 103: a third fiber Bragg grating;
10 k: a kth fiber Bragg grating; 11: a polarization controller;
12: an optical fiber output coupler; 13: the high-fineness electrically-controlled adjustable F-P filter;
14: a spectrum analyzer; 15: scanning F-P interferometer.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention are described in further detail below.
Compared with the background technology, the single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system provided by the invention can effectively expand the functions of the system and reduce the use cost of the optical fiber gas concentration detection system.
Referring to fig. 1, the single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system designed by the invention mainly comprises: the thulium-doped fiber laser device, the gas fiber sensing structure and the monitoring device.
Wherein, thulium-doped fiber laser includes: 1570nm distributed feedback Bragg semiconductor laser 1, an erbium-doped optical fiber amplifier 2, an 1570/2000nm wavelength division multiplexer 3, a first thulium-doped optical fiber 4, a unidirectional optical fiber isolator 5, a single-mode optical fiber 6 with a fiber core/cladding diameter of 10/125 microns, a polarization controller 11, an output coupler 12 and a high-fineness electrically-controlled adjustable F-P filter 13.
Wherein, gaseous optical fiber sensing structure includes: the optical fiber laser comprises a gas chamber 7, a fiber circulator 8, a second thulium-doped fiber 9, a first fiber Bragg grating 101, a second fiber Bragg grating 102, a third fiber Bragg grating 103 and a kth fiber Bragg grating (10 k).
In specific implementation, the wavelength division multiplexer 3, the first thulium-doped optical fiber 4, the optical fiber isolator 5, the single-mode optical fiber 6, the air chamber 7, the optical fiber circulator 8, the second thulium-doped optical fiber 9, the optical fiber bragg grating 10, the polarization controller 11, the output coupler 12 and the F-P filter 13 jointly form a ring cavity thulium-doped optical fiber laser (i.e., a sensing ring cavity).
Wherein, monitoring devices includes: a spectrum analyzer 14 and a scanning F-P interferometer 15. The bandwidth of the fiber Bragg grating is 0.5nm, and the central wavelength is lambda in turn1＝1899.71nm、λ2＝1901.98nm、λ3＝1911nm、λ4＝1918.38nm、λ5＝1927.95nm、λ6＝1942.54nm、λ7The absorption peaks at 1948.22nm correspond to absorption peaks of gases such as water vapor, ozone, acetylene, nitric oxide, hydrogen sulfide, ammonia gas, and carbon dioxide.
Referring to fig. 1, the working process of the single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system of the invention is as follows: 1570nm laser output by the distributed feedback Bragg semiconductor laser 1 is amplified by the erbium-doped fiber amplifier 2 to serve as pump light, and the pump light is coupled into the first thulium-doped fiber 4 through the 1570/2000nm wavelength division multiplexer 3, and the first thulium-doped fiber 4 serves as a gain medium. The optical fiber isolator 5 can ensure that the 2000nm wave band laser is transmitted back and forth in the ring cavity thulium-doped optical fiber laser anticlockwise. The 2000nm band laser interacts with the gas to be measured inside fully each time it passes through the gas chamber 7. The laser light that is ultimately output from the fiber output coupler 12 will carry both gas composition and concentration information.
The output wavelength of the sensing system is tuned through the high-fineness electrically-controlled adjustable F-P filter 13, and when the scanning wavelength falls into the working wavelength range of the high-fineness electrically-controlled adjustable F-P filter 13, due to mode competition effect in the annular cavity, the identification of the gas type can be completed through automatic switching of the channel only when the current channel is in a working state, so that the link of subsequent signal processing is omitted, and the detection rate is improved. When realizing the mist concentration detection, because the second thulium-doped optical fiber 9 is not pumped by the pump source, acts as saturable absorber here, can narrow the linewidth of active cavity optical fiber sensing system output signal light, and then utilizes this narrow linewidth characteristic to improve mist discernment degree and concentration detection sensitivity.
In the device, a plurality of fiber Bragg gratings (101-10k) and a high-fineness electrically-controlled adjustable F-P filter 13 are selected as frequency selection devices, and CO is determined according to an HITRAN database2、NH3、H2S、O3、NO、CH4And (3) when the resonance absorption peak value of the gas in the 2 mu m wave band exists, reasonably selecting the transmission wavelength of each fiber Bragg grating, so that the transmission wavelength and the resonance absorption peak value of different gases have one-to-one correspondence.
The scanning F-P interferometer 13 is used to monitor the longitudinal mode operation state of the output signal light. The spectrum analyzer 14 is used to monitor the spectrum of the output laser light, as shown in fig. 2. By analyzing the spectrogram of the output laser, the gas composition and corresponding concentration can be obtained simultaneously: the composition of the detectable gas is obtained by analyzing whether the central wavelength intensity of the reflected light changes, so that the identification of the components is realized; the absorption intensity of the detectable gas can be obtained by analyzing the variation of the central wavelength intensity of the reflected light, so that the detection of the gas concentration is realized, and the simultaneous sensing of the component and the concentration of the mixed gas is realized.
The thulium-doped fiber laser in the sensing system can realize laser output in a wavelength range of 1650nm to 2200 nm. Since the thulium-doped fiber has a wider emission spectrum than the erbium-doped fiber, detection of a larger variety of gases can be achieved. For CO2、NH3、CH4、H2S、O3For gases, the peak value of the resonance absorption peak of the gases in the 2 mu m wave band can be up to 70 times compared with that of the gases in the 1.5 mu m wave band, thereby being beneficial to improving the detection sensitivity of the system and realizing the measurement of lower gas concentration. The optical fiber sensing system designed by the invention can also realize high-sensitivity detection of the concentrations of gases such as NO, HBr, HCl and the like, halogen hydride, water vapor and the like.
Since the absorption lines of gases at a certain wavelength are generally very narrow, when the laser is used for detecting the concentrations of a plurality of gases with small intervals between resonance absorption peaks, the laser with a wide line width may not be able to detect the concentrations of all gases, or even cannot distinguish all gases contained in the current environment. The single-frequency thulium-doped optical fiber active inner cavity optical fiber sensing system not only can improve the capability of distinguishing different gases by narrowing the laser line width, but also can improve the sensitivity and the measurement precision of gas concentration detection while improving the resolution ratio, thereby having important significance for atmospheric environment monitoring.
Compared with a common optical fiber sensor, the optical fiber sensing system can effectively improve the multiplexing capability of the system and realize the accurate identification and concentration detection of the components of the mixed gas. The invention greatly reduces the volume of the optical fiber sensing system, improves the structural stability of the system, and has the advantages of simple structure, small volume and the like. Meanwhile, the optical fiber sensing system has good portability and has very important significance for improving the performance of the mixed gas optical fiber sensing system and expanding the range of the gas which can be covered by the optical fiber sensing detection system.
The invention adopts the air chamber 7 as a sensing device, adopts the high-fineness electrically-controlled adjustable F-P filter 13 as a frequency selection device to realize the tuning of laser wavelength, adopts the three-port optical fiber circulator 8 to connect a plurality of optical fiber Bragg gratings corresponding to different gas absorption peak wavelengths into the sensing annular cavity, and adopts the second thulium-doped optical fiber 9 which is not pumped as a saturable absorber to narrow the laser line width, thereby realizing the accurate identification and concentration detection of the high-sensitivity mixed gas component.
Because different fiber Bragg gratings have different reflection peak wavelengths, the fiber Bragg gratings which respectively correspond to different kinds of gas absorption peak wavelengths one by one are connected into the sensing annular cavity, the reusability of the sensing system is improved, the volume of the fiber gas detection device is reduced, the detection of mixed gas can be effectively realized, and the performance of the gas sensor is greatly enriched.
The tail fibers of the devices included in the present invention are first fused by an optical fiber fusion splicer, and the sensing system is constructed according to fig. 1. 1570nm laser is used as pumping light, a first thulium-doped optical fiber 4 next to the 1570/2000nm wavelength division multiplexer 3 in the sensing ring cavity is used as a gain medium, a second thulium-doped optical fiber 9 which is not pumped is used as a saturable absorber, the laser has nonlinear absorption characteristics, the line width of the laser can be narrowed, and therefore the thulium-doped optical fiber laser outputs narrow-line-width laser with 2000nm wave band.
The gas chamber 7 is filled with a gas mixture to be detected. And when the wavelength is tuned to coincide with the reflection wavelength of a certain fiber Bragg grating (101-10k), the wavelength resonates in the sensing ring cavity and outputs the narrow linewidth laser. Because the central wavelength of the reflected light and the gas absorption peak have a one-to-one correspondence relationship, the identification of the components of the mixed gas is realized according to the existence of the change of the intensity of the reflection peak, and the detection of the gas concentration can be realized according to the change of the intensity of the reflection peak. If the gas mixture to be measured in the gas cell 7 does not contain a gas corresponding to the wavelength, the intensity of the output laser beam is observed to be constant in the spectrum analyzer 14. If the gas cell 7 contains such a gas, a decrease in the intensity of the output laser light can be observed on the spectrum analyzer 14; the higher the gas concentration is, the more the intensity is reduced, and the later calibration can realize the concentration detection.
The working wavelength of the optical fiber of the 1570/2000nm wavelength division multiplexer 3 at one input port is 1570nm, and the working wavelengths of the optical fibers at the other two ports are both 2000nm, which are well known to those skilled in the art, and are not described in detail in the embodiments of the present invention.
Among them, the HITRAN (HIgh-resolution transmision) molecular absorption database is a widely used spectral parameter database, which is well known to those skilled in the art, and is not described in detail in the embodiments of the present invention. In the embodiment of the present invention, except for the specific description of the model of each device, the model of other devices is not limited, as long as the device can perform the above functions.
Those skilled in the art will appreciate that the drawings are only schematic illustrations of preferred embodiments, and the above-described embodiments of the present invention are merely provided for description and do not represent the merits of the embodiments.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.
Claims (8)
1. The utility model provides a single-frequency thulium-doped inner chamber mixed gas component discernment concentration detection optical fiber sensing system which characterized in that, the system includes: the optical fiber laser comprises an annular cavity thulium-doped optical fiber laser consisting of an 1570/2000nm wavelength division multiplexer, a first thulium-doped optical fiber, a one-way optical fiber isolator, a single-mode optical fiber with the fiber core/cladding diameter of 10/125 mu m, an air chamber, an optical fiber circulator, a second thulium-doped optical fiber, a plurality of optical fiber Bragg gratings, a polarization controller, an output coupler and an electric control adjustable F-P filter, and further comprises a monitoring device consisting of a spectrum analyzer and a scanning F-P interferometer;
1570nm laser of distributed feedback Bragg semiconductor laser output, as the pump light after erbium-doped fiber amplifier enlargies, get into annular chamber through 1570/2000nm wavelength division multiplexer coupling and mix in the thulium fiber laser, one-way fiber isolator is used for guaranteeing that 2000nm wave band laser is anticlockwise round trip transmission in this annular chamber mixes thulium fiber laser, 2000nm wave band laser is at every turn through during the air chamber, all interact fully with inside gaseous the awaiting measuring, finally carry the laser of gaseous composition and concentration dual information from output coupler output.
2. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 1, further comprising a monitoring device consisting of a spectrum analyzer and a scanning F-P interferometer.
3. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 1, wherein the electrically controlled tunable F-P filter is used for tuning the output wavelength, and when the current channel is in a working state, the identification of the gas type is completed through the automatic switching of the channel.
4. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 1, wherein when the mixed gas concentration detection is realized, the second thulium-doped optical fiber is used as a saturable absorber, the line width of the output signal light is narrowed, and the mixed gas identification degree and the concentration detection sensitivity are improved by utilizing the narrow line width characteristic.
5. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 1, wherein a plurality of optical fiber Bragg gratings and an electrically controlled adjustable F-P filter are used as frequency selection devices, the resonance absorption peak value of the gas in the 2 μm wave band is determined according to an HITRAN database, and the transmission wavelength of each optical fiber Bragg grating is selected to have a one-to-one correspondence relationship with the resonance absorption peak values of different gases.
6. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 2, wherein the scanning F-P interferometer is used for monitoring the longitudinal mode operation state of the output signal light; the spectrum analyzer is used for monitoring the spectrum of the output laser,
by analyzing the spectrogram of the output laser, the gas composition and corresponding concentration are obtained simultaneously: the composition of the detectable gas is obtained by analyzing whether the central wavelength intensity of the reflected light changes, so that the identification of the components is realized; the absorption intensity of the detected gas is obtained by analyzing the variation of the central wavelength intensity of the reflected light, so that the detection of the gas concentration is realized, and the simultaneous sensing of the component and the concentration of the mixed gas is realized.
7. The single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system according to claim 1, wherein the optical fiber circulator connects a plurality of fiber bragg gratings corresponding to different gas absorption peak wavelengths into the annular cavity thulium-doped fiber laser.
8. The single frequency thulium doped internal cavity mixed gas component identification concentration detection optical fiber sensing system according to any one of claims 1-7, wherein the system is used for realizing high sensitivity detection of halogen hydride and gas concentration.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111025021.5A CN113804649B (en) | 2021-09-02 | 2021-09-02 | Single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111025021.5A CN113804649B (en) | 2021-09-02 | 2021-09-02 | Single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113804649A true CN113804649A (en) | 2021-12-17 |
| CN113804649B CN113804649B (en) | 2024-07-09 |
Family
ID=78942144
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111025021.5A Active CN113804649B (en) | 2021-09-02 | 2021-09-02 | Single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113804649B (en) |
Citations (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1889313A (en) * | 2005-06-27 | 2007-01-03 | 北京理工大学 | Narrow-line width single frequency optical fiber laser |
| CN101059433A (en) * | 2007-06-05 | 2007-10-24 | 天津大学 | Quasi-distribution type hybrid gas sensing system based on internal chamber optical fiber laser |
| CN102288563A (en) * | 2011-07-21 | 2011-12-21 | 天津大学 | Active cavity absorption acetylene concentration detection system and method thereof |
| KR101331657B1 (en) * | 2012-05-11 | 2013-11-20 | 인하대학교 산학협력단 | Single longitudinal-mode fiber laser divece with a controllable saturable absorber |
| CN103487402A (en) * | 2013-10-14 | 2014-01-01 | 北京信息科技大学 | Ring cavity inner-cavity optical fiber laser gas detection system with saturated absorption optical fibers |
| WO2014089858A1 (en) * | 2012-12-13 | 2014-06-19 | 华南理工大学 | Tunable narrow-linewidth array single-frequency fiber laser |
| US20140176951A1 (en) * | 2011-08-18 | 2014-06-26 | Kun Liu | Multi-band multiplexing intra-cavity gas sensing system and method |
| CN104577676A (en) * | 2015-01-14 | 2015-04-29 | 天津大学 | Carbon dioxide thulium-doped all-optical-fiber annular laser detection method and laser unit |
| CN105244738A (en) * | 2015-10-14 | 2016-01-13 | 安徽大学 | Single-frequency narrow linewidth green laser device |
| CN106329296A (en) * | 2016-09-21 | 2017-01-11 | 中国科学院西安光学精密机械研究所 | Watt-level 1.7 mu m narrow-linewidth all-fiber thulium-doped quartz fiber laser |
| CN107831136A (en) * | 2017-10-28 | 2018-03-23 | 李岩 | Alkanes mixed gas Laser Detecting Set |
| CN108899748A (en) * | 2018-06-22 | 2018-11-27 | 长春理工大学 | Narrow linewidth mode locking thulium-doped fiber laser with high repetition frequency |
| CN109659802A (en) * | 2019-01-31 | 2019-04-19 | 华南理工大学 | A kind of multi-wavelength single-frequency Q adjusting optical fiber laser |
| CN110907400A (en) * | 2019-05-28 | 2020-03-24 | 天津工业大学 | A gas detection device based on microchannel polarization-maintaining fiber Sagnac interference structure |
| CN111146674A (en) * | 2019-12-27 | 2020-05-12 | 北京邮电大学 | Ultra-narrow linewidth single-frequency fiber laser based on double-ring resonant cavity |
| CN111668684A (en) * | 2019-03-06 | 2020-09-15 | 绍兴钠钇光电有限公司 | Ultra-narrow bandwidth filter and high-power single longitudinal mode narrow linewidth optical fiber laser |
| CN112098330A (en) * | 2020-09-22 | 2020-12-18 | 中国人民解放军国防科技大学 | Atomic concentration measuring device and method for alkali metal vapor laser |
-
2021
- 2021-09-02 CN CN202111025021.5A patent/CN113804649B/en active Active
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1889313A (en) * | 2005-06-27 | 2007-01-03 | 北京理工大学 | Narrow-line width single frequency optical fiber laser |
| CN101059433A (en) * | 2007-06-05 | 2007-10-24 | 天津大学 | Quasi-distribution type hybrid gas sensing system based on internal chamber optical fiber laser |
| CN102288563A (en) * | 2011-07-21 | 2011-12-21 | 天津大学 | Active cavity absorption acetylene concentration detection system and method thereof |
| US20140176951A1 (en) * | 2011-08-18 | 2014-06-26 | Kun Liu | Multi-band multiplexing intra-cavity gas sensing system and method |
| KR101331657B1 (en) * | 2012-05-11 | 2013-11-20 | 인하대학교 산학협력단 | Single longitudinal-mode fiber laser divece with a controllable saturable absorber |
| WO2014089858A1 (en) * | 2012-12-13 | 2014-06-19 | 华南理工大学 | Tunable narrow-linewidth array single-frequency fiber laser |
| CN103487402A (en) * | 2013-10-14 | 2014-01-01 | 北京信息科技大学 | Ring cavity inner-cavity optical fiber laser gas detection system with saturated absorption optical fibers |
| US20150102240A1 (en) * | 2013-10-14 | 2015-04-16 | Beijing Information Science & Technology University | Gas detection system using intracavity fiber laser with loop cavity having saturated absorption fiber |
| CN104577676A (en) * | 2015-01-14 | 2015-04-29 | 天津大学 | Carbon dioxide thulium-doped all-optical-fiber annular laser detection method and laser unit |
| CN105244738A (en) * | 2015-10-14 | 2016-01-13 | 安徽大学 | Single-frequency narrow linewidth green laser device |
| CN106329296A (en) * | 2016-09-21 | 2017-01-11 | 中国科学院西安光学精密机械研究所 | Watt-level 1.7 mu m narrow-linewidth all-fiber thulium-doped quartz fiber laser |
| CN107831136A (en) * | 2017-10-28 | 2018-03-23 | 李岩 | Alkanes mixed gas Laser Detecting Set |
| CN108899748A (en) * | 2018-06-22 | 2018-11-27 | 长春理工大学 | Narrow linewidth mode locking thulium-doped fiber laser with high repetition frequency |
| CN109659802A (en) * | 2019-01-31 | 2019-04-19 | 华南理工大学 | A kind of multi-wavelength single-frequency Q adjusting optical fiber laser |
| CN111668684A (en) * | 2019-03-06 | 2020-09-15 | 绍兴钠钇光电有限公司 | Ultra-narrow bandwidth filter and high-power single longitudinal mode narrow linewidth optical fiber laser |
| CN110907400A (en) * | 2019-05-28 | 2020-03-24 | 天津工业大学 | A gas detection device based on microchannel polarization-maintaining fiber Sagnac interference structure |
| CN111146674A (en) * | 2019-12-27 | 2020-05-12 | 北京邮电大学 | Ultra-narrow linewidth single-frequency fiber laser based on double-ring resonant cavity |
| CN112098330A (en) * | 2020-09-22 | 2020-12-18 | 中国人民解放军国防科技大学 | Atomic concentration measuring device and method for alkali metal vapor laser |
Non-Patent Citations (1)
| Title |
|---|
| 张海伟: "全光纤单频掺铥光纤激光器和有源内腔光纤传感器技术研究", pages 113 - 133 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113804649B (en) | 2024-07-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ma et al. | Highly sensitive acetylene detection based on multi-pass retro-reflection-cavity-enhanced photoacoustic spectroscopy and a fiber amplified diode laser | |
| CN103487403B (en) | With the dual wavelength combination of fiber-optic laser gas detection system that reference cavity compensates | |
| CN1625680B (en) | Fiber-optic based cavity ring-down spectroscopy apparatus | |
| CN104568829B (en) | Fiber Laser Gas Detection System Using Active Feedback Compensation of Reference Cavity | |
| CN103487402B (en) | With the ring cavity internal chamber optical fiber laser gas detecting system of saturated absorption optical fiber | |
| CN103592261B (en) | All-optical fiber temperature offset-type gas sensor and compensation method thereof | |
| CN102305771B (en) | Multi-waveband aliasing lumen gas sensing system and sensing method | |
| CN102628797B (en) | Active cavity gas detection system based on laser injection mode locking technology | |
| CN101762557A (en) | Gas category classification method and classification device based on active inner cavity absorption spectrum | |
| CN104807765B (en) | The Gas in Oil of Transformer detection means of high sensitivity spectral absorption damped oscillation chamber | |
| CN207232015U (en) | A kind of many reference amounts mixing sensor-based system based on optical fiber inner-cavity structure | |
| CN106290248A (en) | Oil-gas mining and accumulating dangerous leakage gas optical fiber sensing system device | |
| CN108801977A (en) | Without calibration trace amounts of carbon 12 and 13 carbon dioxide gas detection device of carbon and method | |
| CN102288563A (en) | Active cavity absorption acetylene concentration detection system and method thereof | |
| Yang et al. | Highly sensitive dual-wavelength fiber ring laser sensor for the low concentration gas detection | |
| Wang et al. | Gas concentration sensing based on fiber loop ring-down spectroscopy: a review | |
| CN103344265A (en) | Fiber bragg grating demodulation instrument | |
| CN112903628B (en) | Trace gas detection method under negative pressure state | |
| CN113804649B (en) | Single-frequency thulium-doped inner cavity mixed gas component identification concentration detection optical fiber sensing system | |
| CN1267696C (en) | Apparatus for measuring ultra narrow laser line width by Brillouin optical fibre ring laser and measuring method | |
| Chan et al. | All‐optical remote monitoring of propane gas using a 5‐km‐long, low‐loss optical fiber link and an InGaP light‐emitting diode in the 1.68‐μm region | |
| CN208385830U (en) | Tunable single longitudinal mode optical-fiber laser, gas concentration detection apparatus | |
| CN108512024A (en) | Tunable single longitudinal mode optical-fiber laser, gas concentration detection apparatus and method | |
| CN115494046B (en) | A method and device for optical fiber distributed detection of trace multi-component gas | |
| CN116930121A (en) | Fiber bragg grating demodulation method and device based on VCSEL and acetylene absorption peak |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |