CN115372357A - System and method for real-time monitoring and purifying gaseous OH in hollow-core optical fiber - Google Patents
System and method for real-time monitoring and purifying gaseous OH in hollow-core optical fiber Download PDFInfo
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 85
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- 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
- G01N21/84—Systems specially adapted for particular applications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
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- 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
- G02B6/032—Optical fibres with cladding with or without a coating with non solid core or cladding
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Abstract
A system and method for real-time monitoring and purification of gaseous OH in hollow-core optical fibers, the apparatus comprising: the device comprises a laser output module, a coupler, a concentration monitoring and purifying module, an air chamber, a collimator and a photoelectric detector. Laser emitted by the laser output module is focused into the optical fiber to be detected through the coupler, the emitted laser of the optical fiber to be detected is received by the photoelectric detector after being collimated by the collimator, and a signal is fed back to the concentration monitoring and purifying module, the concentration monitoring and purifying module in the concentration monitoring and purifying module is communicated with the air chamber, the concentration of OH in the optical fiber is detected in real time, meanwhile, the self-starting of the purifier is completed, the self-circulation of concentration monitoring and purification is realized, and the content of OH in the optical fiber is reduced to be below a preset value. The invention solves the problems of loss, sensing signal interference and optical fiber aging caused by the existence of OH in the hollow optical fiber, and provides a solid foundation for the wide application of the hollow optical fiber.
Description
Technical Field
The invention relates to a hollow-core optical fiber, in particular to a system and a method for monitoring and purifying gaseous hydroxyl (OH) in the hollow-core optical fiber in real time.
Background
The emergence of Hollow Core Fiber (HCF) provides an ideal transmission medium and experimental platform for many fields such as laser, nonlinear optics, sensing, communication, quantum, biology, etc. On one hand, the HCF is used as a bendable hollow optical fiber, the propagation property of light in the hollow optical fiber is similar to that of light propagating in free space, the limit of absorption of a solid dielectric material is broken, and an ideal optical environment with low dispersion, low nonlinearity and low time delay is created in the optical fiber; on the other hand, the HCF is used as a platform for interaction of light and substances, laser is confined in the hollow fiber core with the micron order for long-distance transmission, the limit of laser space transmission diffraction limit is broken, and the interaction of the light and the substances is greatly enhanced. However, the micro-structure area in the HCF makes water vapor easily diffuse into the inner area of the optical fiber from the two open ends of the optical fiber, the water vapor increases the transmission loss of the HCF, corrodes the optical fiber structure and generates strong noise interference, and great obstruction is brought to the field of sensing using the HCF.
It is well known that HCF is made of high purity quartz, and therefore the reduction of OH in HCF is generally achieved by reducing the OH content in the fused quartz material in a vacuum and high temperature environment. This method is costly, has a short shelf life and is susceptible to secondary contamination. Sealing the ends of the optical fiber to store, while reducing the OH content that diffuses into the optical fiber, the OH introduced during the manufacturing process remains inside the optical fiber and affects subsequent use. In 2019, the university of NanoApton connects one end of a hollow optical fiber to a nitrogen source with the pressure of 6Bar, and the other end of the hollow optical fiber is opened to the atmosphere for simple unilateral purging, so that the water vapor in the optical fiber is reduced by dozens of ppm. For the mid-infrared band with higher measurement sensitivity requirement, even if the water vapor concentration in the optical fiber is in the order of parts per million (ppm), the measurement of other spectrum signals can be influenced, such as the signal-to-noise ratio is reduced and the spectrum of the target signal is overlapped. Therefore, in order to reduce the loss of the optical fiber, delay the aging and corrosion speed of the optical fiber, improve the sensing accuracy of the hollow-core optical fiber and expand the application field of the hollow-core optical fiber, it is necessary to develop a method for purifying OH in the hollow-core optical fiber with strong timeliness, convenient use and low cost.
Disclosure of Invention
Aiming at the defects and shortcomings of high cost, short shelf life, low purification degree and easiness in secondary pollution of OH in the existing purified hollow-core optical fiber, the invention provides a system and a method for monitoring and purifying gaseous hydroxyl (OH) in the hollow-core optical fiber in real time, and the method and the system for monitoring and purifying gaseous OH in the hollow-core optical fiber in real time, which are interactive, self-starting, convenient, easy to realize and low in cost, combine the real-time monitoring of the concentration of OH in the hollow-core optical fiber with the purification of the hollow-core optical fiber, form a feedback mechanism between the monitoring and the purification, automatically start a purification cycle, realize the automation, visualization and controllability of the purification process of OH in the hollow-core optical fiber, and improve the reliability and convenience of the system.
The technical solution of the invention is as follows:
a system for real-time monitoring and purification of gaseous OH in hollow-core optical fiber, comprising: laser output module, coupler, first air chamber, second air chamber, concentration monitoring and purification module, collimater and photoelectric detector, concentration monitoring and purification module contain concentration detection, gas circuit, clarifier, first air chamber, second air chamber have atmospheric pressure monitor and have the metal cavity of slope terminal surface, the optic fibre that awaits measuring is arranged in the metal cavity of first air chamber, second air chamber between, the laser of laser output module output pass through in proper order coupler, first air chamber, the optic fibre that awaits measuring, second air chamber, collimater and photoelectric detector's input link to each other, concentration monitoring and purification module 1 port and 2 port respectively with first air chamber, second air chamber link to each other, concentration monitoring and purification module 3 ports with photoelectric detector's output link to each other, concentration monitoring and purification module receive photoelectric detector's data, handle data and purify the optic fibre that awaits measuring, acquire the concentration information of OH in the optic fibre that awaits measuring.
The first gas chamber and the second gas chamber respectively comprise a gas pressure monitor and a metal cavity with an inclined end face, and the gas pressure monitor and the metal cavity are used for eliminating interference phenomena and improving the signal-to-noise ratio of absorption spectra.
The rear ends of the first air chamber and the second air chamber adopt the plug-in structure, the optical fiber to be tested can be replaced under the condition that the front end is not detached, and the optical fiber testing device is convenient to use and simple to operate.
The first air chamber and the second air chamber are respectively provided with penetrating holes on the upper surface and the side surface, so that the air pressure monitoring and the purification are not influenced mutually and are controlled independently.
The purifier achieves the purification purpose through vacuum purification or high-pressure purification.
The method for monitoring and purifying the gaseous OH in the hollow-core optical fiber in real time by using the system for monitoring and purifying the gaseous OH in the hollow-core optical fiber in real time comprises the following steps:
1) Connecting two ends of the optical fiber to be detected with the first air chamber and the second air chamber, wherein the first air chamber and the second air chamber are both provided with air pressure monitoring modules, so that the pressure in the optical fiber to be detected can be observed and controlled in real time conveniently;
2) The laser output module enables the laser to output modulated laser through current and temperature modulation, adjusts the wave band and scanning frequency output by the laser according to actual requirements, selects the OH wavelength or wave band to be purified and the length of the optical fiber to be purified, and focuses and couples the optical fiber to be detected through the coupler; after laser emitted from the emergent end of the optical fiber to be detected is collimated by the collimator, the light intensity of OH in the optical fiber to be detected is received by the photoelectric detector, and the optical signal is transmitted to the concentration monitoring and purifying module after being converted into an electric signal;
3) The concentration monitoring and purifying module is communicated with the gas circuit, concentration monitoring and purification are simultaneously realized, the concentration monitoring and purifying module processes electric signals transmitted by the photoelectric detector on the one hand, and controls the purifier to purify the optical fiber to be detected and feed back the purified data in real time on the other hand, OH concentration monitoring, information updating and purification are realized, self-circulation of monitoring and purification is formed, and until the concentration monitoring and purifying module collects the optical fiber, the OH concentration in the optical fiber reaches below a preset value, and purification is completed.
Compared with the prior art, the invention has the following beneficial effects:
1. the invention purifies OH in the hollow optical fiber, improves the precision of the hollow optical fiber in the aspects of sensing and detection, and enlarges the application range of the hollow optical fiber;
2. the method realizes the closed-loop feedback and automation of OH monitoring and purification in the hollow-core optical fiber by utilizing the means of combining real-time monitoring and purification, and improves the intellectualization, visualization, reliability and controllability of the system;
3. compared with the method for reducing the OH concentration in the early-stage material fused quartz, the method for purifying the OH in the hollow-core optical fiber has the advantages that the OH is removed after the hollow-core optical fiber is drawn, the system provided by the invention is more time-efficient, and the possibility of secondary pollution is avoided.
Drawings
FIG. 1 is a schematic diagram of a system for real-time monitoring and purification of gaseous OH in hollow-core optical fiber according to the present invention;
FIG. 2 is a flow chart of the method for real-time monitoring and purifying gaseous OH in a hollow-core optical fiber according to the present invention;
FIG. 3 is a diagram illustrating an embodiment of measuring the presence of H in an optical fiber by applying an OH system for purifying hollow-core optical fiber based on TDLAS technology 2 A plot of the O absorption spectrum signal;
FIG. 4 is a diagram of measuring the absorption spectrum signal in the hollow-core fiber after purification by applying the TDLAS technology to purify the OH system in the hollow-core fiber according to the embodiment of the present invention
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1, the system for monitoring and purifying gaseous OH in a hollow-core optical fiber in real time according to the present invention includes a laser output module 1, a coupler 2, a first air chamber 3, a second air chamber 4, a concentration monitoring and purifying module 5, a collimator 6, and a photodetector 7, where the concentration monitoring and purifying module 5 includes a concentration detector 51, an air path 52, and a purifier 53, the first air chamber 3 and the second air chamber 4 have an air pressure monitor 32 and a metal cavity 31 with an inclined end surface, two ends of an optical fiber to be detected are connected to the metal cavities 31 of the first air chamber 3 and the second air chamber 4, laser output by the laser output module 1 is sequentially connected to the input end of the photodetector 7 through the coupler 2, the first air chamber 3, the optical fiber to be detected, the second air chamber 4, and the collimator 6, a port 1 and a port 2 of the concentration monitoring and purifying module 5 are respectively communicated to the first air chamber 3 and the second air chamber 4, a port 3 of the concentration monitoring and purifying module 5 is connected to the output end of the photodetector 7, the concentration monitoring and purifying module 5 receives data of the optical fiber to be detected, and processes data of the optical fiber to obtain data to be detected;
the first gas chamber 3 and the second gas chamber 4 both comprise a gas pressure monitor 32 and a metal cavity 31 with an inclined end face, and are used for eliminating interference phenomena and improving the signal-to-noise ratio of absorption spectra.
The rear ends of the first air chamber 3 and the second air chamber 4 adopt a plug-in structure, the optical fiber to be tested can be replaced without disassembling the front end, and the optical fiber testing device is convenient to use and simple to operate.
The first air chamber 3 and the second air chamber 4 are respectively provided with penetrating holes on the upper surface and the side surface, so that the air pressure monitoring and the purification are not influenced mutually and are controlled independently.
The purifier 53 achieves the purification purpose through vacuum purification or high-pressure purification.
The method for monitoring and purifying the gaseous OH in the hollow-core optical fiber in real time by using the system for monitoring and purifying the gaseous OH in the hollow-core optical fiber in real time comprises the following steps:
1) Connecting two ends of an optical fiber to be measured with plug-in structures at the rear ends of metal cavities 31 of a first air chamber 3 and a second air chamber 4, wherein the first air chamber 3 and the second air chamber 4 are both provided with air pressure monitoring modules 32, so that the pressure intensity in the optical fiber to be measured can be observed and controlled in real time conveniently;
2) The laser output module 1 makes the laser output modulated laser through current and temperature modulation, adjusts the output wave band and scanning frequency of the laser according to actual requirements, selects the OH wavelength or wave band to be purified and the length of the optical fiber to be purified, adjusts the output wave band and scanning frequency of the laser according to actual requirements, selects the OH wavelength or wave band to be purified, and focuses and couples the length of the optical fiber to be purified into the optical fiber to be detected through the coupler 2; after laser emitted from the emergent end of the optical fiber to be detected collimates light beams by the collimator 6, the light intensity of OH in the optical fiber to be detected is received by the photoelectric detector 7, and optical signals are converted into electric signals and then transmitted to the concentration monitoring and purifying module 5;
3) Concentration monitoring 51 and the clarifier 53 of concentration monitoring and purification module 5 pass through gas circuit 52 intercommunication, realize concentration monitoring and purification simultaneously, concentration monitoring and purification module 5 on the one hand carry out data processing to the signal of telecommunication of photoelectric detector 7 transmission, on the other hand control clarifier 53 to the optic fibre that awaits measuring purify, realize OH concentration monitoring, information renewal and purification treatment, form the self-loopa of monitoring and purification, until concentration monitoring and purification module 5 gather the optic fibre in OH concentration reach below the default, accomplish the purification.
A method for monitoring and purifying gaseous OH in a hollow-core optical fiber in real time comprises the following steps:
step 100, enabling a laser to output modulated laser by a laser output module 1 through current and temperature modulation;
200, respectively placing two ends of an optical fiber to be tested at the centers of an air chamber 3 at an incident end and an air chamber 4 at an emergent end, and keeping the distance of about 1mm between the end face of the optical fiber to be tested and window sheets at the ports of the air chambers 3 and 4;
step 300, collimating and focusing the emergent laser through the coupler 2 to realize mode matching, entering an incident end of the optical fiber to be tested, and carrying out single-mode transmission;
step 400, collimating the laser emitted from the emergent end of the optical fiber to be detected by the collimator 6, entering a receiving panel of the photoelectric detector 7, performing photoelectric signal conversion, and finally feeding the signal back to the concentration monitoring and purifying module 5 for signal processing;
step 500, the concentration monitoring and purifying module 5 is turned on, after the electrical signal is received by setting the concentration minimum threshold, the concentration information of OH in the optical fiber to be detected is obtained through data processing, the purifier is automatically controlled to be turned on, the optical fiber to be detected is purified until the concentration of OH in the optical fiber to be detected reaches a preset value or less, and the purification of OH in the optical fiber to be detected is completed.
Compared with the existing methods of reducing the OH concentration in the initial material fused quartz, hermetically storing the optical fiber, performing unilateral purging and the like, the method for purifying the hollow-core optical fiber OH has the advantages of high timeliness, low cost, high purification degree and convenience in use.
Example 1
The characteristics of the structure of the OH system in the purified hollow-core fiber in the present example are as follows:
the line width of a laser spectral line emitted by the laser output module 1 is less than 3MHz, and a scanning period simultaneously covers a target signal and an OH signal absorption spectral line in an optical fiber.
The coupler 2 performs spatial light beam transformation on laser emitted by the laser 2, realizes mode matching with the optical fiber, has a reflectivity of less than 15% of the lens coated with the antireflection film, and effectively improves the coupling efficiency of the spatial light beam and the optical fiber.
The first air chamber 3 of the incident end and the second air chamber 4 of the emergent end have the same structure, the end face of the metal cavity 31 is provided with an 8-degree inclination angle and a sapphire window sheet plated with a high-transparency film, interference caused among all devices is removed, an air pressure monitor 32 is installed, and air pressure conditions of two ends of an optical fiber to be detected are monitored in real time.
The concentration monitoring and purifying module 5 processes the electric signal transmitted by the photoelectric detector 7 on one hand, controls the purifier 53 to purify the optical fiber to be detected and feeds back the purified data in real time on the other hand, and the two parts form a feedback mechanism, so that the OH concentration information updating and the purification processing are performed in parallel until the purification process is completed.
As shown in fig. 1, the concentration monitoring and purifying module 5 includes a concentration monitoring module 51, an air path 52 and a purifier 53, wherein the concentration monitoring module 51 controls the purifier 53 to be turned on and off while processing data to obtain the OH concentration in the optical fiber to be detected, and is convenient to operate and started by one key when purifying the optical fiber to be detected.
The collimator 6 is a combination of a small aperture diaphragm, a narrow-band filter and a focusing lens, and the aperture of the small aperture diaphragm is adjustable within 5 mm; the central wavelength of the narrow-band filter is customized according to the actual measurement spectral line, and the bandwidth is 50nm; the focusing lens is a calcium fluoride or sapphire lens.
The applicable wavelength range of the photoelectric detector 7 is determined according to the wavelength of an actual measurement spectral line, and the applicable wavelength range can be a photoelectric detector of silicon, indium gallium arsenic, indium telluride and the like, and the photoelectric detector has fixed gain or adjustable gain.
The operation process of the OH system in the hollow-core optical fiber is as follows:
the laser output module 1 outputs the emergent laser which is initially set;
placing two ends of an optical fiber to be tested at the centers of a first air chamber 3 at an incident end and a second air chamber 4 at an emergent end respectively, wherein the distance between the end surface of the optical fiber to be tested and window sheets at the ports of the first air chamber 3 and the second air chamber 4 is kept to be about 1 mm; after the outgoing laser is collimated and focused by the coupler 2, mode matching is realized, the outgoing laser enters the incident end of the optical fiber to be detected, and single-mode transmission is carried out; laser emitted from the emergent end of the optical fiber to be detected enters the receiving panel of the photoelectric detector 7 through collimation of the collimator 6, photoelectric signal conversion is carried out, finally, the signal is fed back to the concentration monitoring and purifying module 5 for signal processing, the purifier 53 judges concentration information given by the concentration monitoring module 51, the optical fiber to be detected starts to be purified until the concentration of OH in the optical fiber to be detected reaches a preset value or below, and the purification of OH in the optical fiber to be detected is completed.
The invention utilizes a feedback mechanism formed by combining concentration monitoring and purification, and a method for automatically starting purification treatment, thereby realizing the automatic and visual OH removal process of simultaneous removal and simultaneous measurement; the invention utilizes the advantages that the laser, the monitoring module and the purification means can be selected and replaced, thereby enlarging the OH wave band which can be purified; compared with the existing methods of reducing the OH concentration in the initial material fused quartz, hermetically storing the optical fiber, purging the single side and the like, the method for purifying the hollow-core optical fiber OH provided by the invention has the characteristics of good timeliness, low cost, high purification degree, convenience in use and repeatability.
Example 2
On the basis of the system, the operation flow is as shown in fig. 2, a laser output module 1 emits laser with a preset scanning frequency and wavelength, two ends of the optical fiber to be detected are placed in a first air chamber 3 and a second air chamber 4, the laser is focused through a coupler 2, enters the optical fiber to be detected for transmission after mode matching is achieved, the laser emitted by the optical fiber to be detected is received by a photoelectric detector 7 after being collimated by a collimator 6, and is fed back to a concentration monitoring and purifying module 5 after conversion between optical signals and electric signals, the first air chamber 3 and the second air chamber 4 are communicated with the concentration detecting and purifying module 5, on one hand, data processing is carried out on the electric signals transmitted by the photoelectric detector, on the other hand, the purifier 53 is controlled to purify the optical fiber to be detected and feed back the purified data in real time, and a feedback mechanism is formed by the two parts, so that updating of OH concentration information and purification processing are parallel until the concentration reaches below a threshold value, and a purification process is completed. The wavelength or wavelength band of OH is generally selected according to requirements, and the laser driving and concentration monitoring system selected in this embodiment is a TDLAS system. As shown in FIG. 3, the length of the optical fiber to be measured in this embodiment is 3m, and the selected wavelength is 4029.7cm -1 。
In this embodiment, the OH in the optical fiber to be measured is selectively purified to 4029.7cm -1 Nearby wavelengths, as shown in fig. 4, the absorption spectrum of the purified OH disappears, the whole spectrum is smooth, and the background error is effectively reduced.
In practical application, the output waveband and the scanning frequency of the laser can be adjusted according to actual requirements, the OH wavelength or waveband to be purified and the length of the optical fiber to be purified are selected.
The above embodiments are only exemplary embodiments of the present application, and are not intended to limit the present application, and the protection scope of the present application is defined by the claims. Various modifications and equivalents may be made by those skilled in the art within the spirit and scope of the present application and such modifications and equivalents should also be considered to be within the scope of the present application.
Claims (6)
1. A system for real-time monitoring and purification of gaseous OH in a hollow-core optical fiber, the system comprising: laser output module (1), coupler (2), first air chamber (3), second air chamber (4), concentration monitoring and purification module (5), collimator (6) and photoelectric detector (7), concentration monitoring and purification module (5) contain concentration detection (51), gas circuit (52), clarifier (53), first air chamber (3), second air chamber (4) have atmospheric pressure monitor (32) and have metal chamber (31) of slope terminal surface, the optic fibre that awaits measuring is arranged in between metal chamber (31) of first air chamber (3), second air chamber (4), the laser of laser output module (1) output in proper order through coupler (2), first air chamber (3), the optic fibre that awaits measuring, second air chamber (4), collimator (6) with the input of photoelectric detector (7) link to each other, the optic fibre both ends that await measuring link to each other with first air chamber (3), second air chamber (4) respectively, the 1 port of concentration monitoring and purification module (5) with the first air chamber (3), second air chamber (4) link to each other respectively, the concentration monitoring and purification module (5) the output with the first air chamber (3), second air chamber (4) and photoelectric detector (7) of concentration monitoring module (5) and concentration monitoring module (5), and the concentration monitoring and purifying module (5) receives the data of the photoelectric detector (7), processes the data, purifies the optical fiber to be detected and acquires the concentration information of OH in the optical fiber to be detected.
2. The system for real-time purification of gaseous OH in hollow-core optical fiber according to claim 1, wherein the first and second gas chambers (3, 4) each comprise a gas pressure monitor (32) and a metal cavity (31) with an inclined end face for eliminating interference phenomenon and improving signal-to-noise ratio of absorption spectrum.
3. The system for purifying gaseous OH in hollow-core optical fiber in real time according to claim 1, wherein the rear ends of the first air chamber (3) and the second air chamber (4) adopt a plug-in structure, so that the optical fiber to be detected can be replaced without detaching the front end, and the system is convenient to use and simple to operate.
4. The system for real-time purification of gaseous OH in hollow-core optical fiber according to claim 1, wherein the first air chamber (3) and the second air chamber (4) are respectively provided with through holes on the upper surface and the side surface, so that the air pressure monitoring and purification are not influenced by each other and can be controlled independently.
5. The system for real-time purification of gaseous OH in hollow-core optical fiber according to claim 1, wherein the purifier (53) is designed for purification by vacuum purification or high pressure purification.
6. The method for real-time monitoring and purifying gaseous OH in a hollow-core optical fiber by using the system for real-time monitoring and purifying gaseous OH in a hollow-core optical fiber according to claim 1, comprising the steps of:
1) Placing two ends of an optical fiber to be detected between a first air chamber (3) and a second air chamber (4), wherein the first air chamber (3) and the second air chamber (4) are both provided with an air pressure monitoring module (32) so as to be convenient for observing and controlling the pressure intensity in the optical fiber to be detected in real time;
2) The laser output module (1) enables the laser to output modulated laser through current and temperature modulation, adjusts the output wave band and scanning frequency of the laser according to actual requirements, selects the OH wavelength or wave band to be purified and the length of the optical fiber to be purified, and focuses and couples the optical fiber to be detected through the coupler (2); after laser emitted from the emergent end of the optical fiber to be detected collimates light beams by the collimator (6), the light intensity of OH in the optical fiber to be detected is received by the photoelectric detector (7), and the optical signal is transmitted to the concentration monitoring and purifying module (5) after being converted into an electric signal;
3) Concentration monitoring (51) and clarifier (53) of concentration monitoring and purification module (5) pass through gas circuit (52) intercommunication, realize concentration monitoring and purification simultaneously, concentration monitoring and purification module (5) on the one hand handle the signal of telecommunication of photoelectric detector (7) transmission, on the one hand control clarifier (53) to the optic fibre that awaits measuring purify and feed back the data after the purification in real time, realize OH concentration monitoring, information update and purification treatment, form the self-loopa of monitoring and purification, until concentration monitoring and purification module (5) gather the optic fibre in OH concentration reach below the default, accomplish the purification.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56155827A (en) * | 1980-05-07 | 1981-12-02 | Nippon Telegr & Teleph Corp <Ntt> | Measuring method for oh group concentration distribution in optical fiber |
| EP3006919A1 (en) * | 2014-10-07 | 2016-04-13 | Bundesrepublik Deutschland, vertreten durch das Bundesministerium für Wirtschaft und Technologie | Method for spatially resolved measurement of molecule concentrations and/or temperature by means of optical fibres |
| CN106525742A (en) * | 2016-12-13 | 2017-03-22 | 山东省科学院激光研究所 | Gas concentration monitoring method, apparatus and system |
| CN106872417A (en) * | 2017-03-06 | 2017-06-20 | 大连理工大学 | Using SDBD and the experimental provision and method of emission spectrum detection OH concentration |
| CN207946353U (en) * | 2018-03-29 | 2018-10-09 | 鞍山哈工激光科技有限公司 | A kind of gas concentration detection apparatus |
| CN114200078A (en) * | 2021-11-22 | 2022-03-18 | 中科三清科技有限公司 | Method and device for measuring and calculating concentration of OH free radicals |
-
2022
- 2022-08-19 CN CN202211003421.0A patent/CN115372357B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56155827A (en) * | 1980-05-07 | 1981-12-02 | Nippon Telegr & Teleph Corp <Ntt> | Measuring method for oh group concentration distribution in optical fiber |
| EP3006919A1 (en) * | 2014-10-07 | 2016-04-13 | Bundesrepublik Deutschland, vertreten durch das Bundesministerium für Wirtschaft und Technologie | Method for spatially resolved measurement of molecule concentrations and/or temperature by means of optical fibres |
| CN106525742A (en) * | 2016-12-13 | 2017-03-22 | 山东省科学院激光研究所 | Gas concentration monitoring method, apparatus and system |
| CN106872417A (en) * | 2017-03-06 | 2017-06-20 | 大连理工大学 | Using SDBD and the experimental provision and method of emission spectrum detection OH concentration |
| CN207946353U (en) * | 2018-03-29 | 2018-10-09 | 鞍山哈工激光科技有限公司 | A kind of gas concentration detection apparatus |
| CN114200078A (en) * | 2021-11-22 | 2022-03-18 | 中科三清科技有限公司 | Method and device for measuring and calculating concentration of OH free radicals |
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