CN1888864A - Carbon monoxide and methane integral optical fiber sensing measuring system - Google Patents
Carbon monoxide and methane integral optical fiber sensing measuring system Download PDFInfo
- Publication number
- CN1888864A CN1888864A CN 200610019709 CN200610019709A CN1888864A CN 1888864 A CN1888864 A CN 1888864A CN 200610019709 CN200610019709 CN 200610019709 CN 200610019709 A CN200610019709 A CN 200610019709A CN 1888864 A CN1888864 A CN 1888864A
- Authority
- CN
- China
- Prior art keywords
- modulator
- wavelength
- connects
- optical fiber
- carbon monoxide
- 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
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
This is an integral optical fiber sensor and testing system using for the carbon monoxide and methane. It composes of first DFB laser source, second DFB laser source, first waveform generator, second waveform generator, first wavelength select modulator, second wavelength select modulator, optical fiber coupling implement, sensor detection head, photoelectric conversion module, signal modulate data collection module and microprocessor. The first waveform generator acts on first wavelength select modulator, the latter controls the first DFB laser source and it connects with one import ending of coupling implement by optical fiber. The second waveform generator acts on second wavelength select modulator, the latter controls the second DFB laser source and it connects with another import ending of coupling implement by optical fiber. The fan-out of coupling implement connects with sensor detection head and the latter connects with photoelectric conversion module. The photoelectric conversion module connects with signal modulate and data collection module by lead and the latter connects with microprocessor by lead. The microprocessor controls the first wavelength selecting and modulator, second wavelength selecting and modulator and display modulator.
Description
Technical field
The present invention relates to utilize the field of optical instrument detected gas, specifically belong to a kind of gas absorption spectra detection technique of utilizing and realize the simultaneously-measured system of multiple gases concentration.
Background technology
The gas sensing technology has extremely important status at aspects such as environmental monitoring, industrial gasses process control and mine safeties, studies safe and reliable, highly sensitive harmful gas sensing technology and has great science, society and economic implications.The detection of gaseous species and concentration can be divided into by detecting principle: optical profile type, semiconductor-type, solid electrolyte formula, catalytic combustion type, electric chemical formula etc.Wherein optical type gas sensor has the incomparable advantage of many other sensors, as highly sensitive, corresponding speed is fast, dynamic range is big, anti-electromagnetic interference (EMI), burn-proof and explosion prevention, be difficult for poisoning etc.Optical type gas sensor can be divided into according to detecting principle: absorbing light spectral pattern, fluorescent type, chemical optical fibre material-type etc.Wherein absorbing light spectral pattern sensor has advantages such as highly sensitive, easy to use, that reliability is high and the life-span is long, thereby is subjected to extensive concern.It is an absorbing light wavelength difference of utilizing gas with various, adopts the monochromatic light incident of different wave length, can measure gas with various, and after the light of this wavelength and gas interacted, light intensity will weaken, and by measuring the decay of luminous power, can determine the concentration of gas.
All reflect the research work in this field in present a lot of document, document " many gas sensings of spectral absorption type optical fiber system " (technical device and sensor wherein, 2006, No.2), at fault signature gas detection in the electric system transformer oil, two kinds of gases of acetylene and carbon monoxide have been realized measuring simultaneously.It carries out wavelength-modulated by fiber grating and piezoelectric ceramics (PZT) to wideband light source LED, obtains the narrowband reflection emergent light, realizes the measurement of gas concentration higher sensitivity.
The present invention is directed to the gas of simultaneous two kinds of harmfulness maximums in the Coal Production---the measurement of methane and carbon monoxide, proposition-carbonoxide and methane integral optical fiber sensing measuring system.
Carbon monoxide is a toxic and harmful, and the carbon monoxide of excess will cause serious threat to people's life security.Through regular meeting the phenomenon that carbon monoxide transfinites taking place, except that the carbon monoxide of explosion and blast generation, it has been generally acknowledged that carbon monoxide derives from the coal seam spontaneous fire or other fire have taken place, and the carbon monoxide of depositing is composed in coal seam itself in the seam mining process.Under 30 ℃ of conditions of normal temperature, coal can discharge CO gas; When temperature reaches 70～100 ℃, the oxidation rate aggravation, the carbon monoxide burst size sharply increases, and oxidation rate rises rapidly.In addition, spontaneous combustion of coal seam in the colliery produces a large amount of CO gas on the one hand, harm miner life security; On the other hand, the naked light that spontaneous combustion of coal seam produces exceeds standard if meet gas, also can cause gas explosion accident.Relevant studies show that the concentration Chang Zuowei of carbon monoxide judges the important evidence whether Period of Coal Seam Spontaneous Combustion exists.So, adopt effectively reliable means to measure the generation that carbonomonoxide concentration can be avoided relevant accident.
Gas is the accompaniment of coal mining equally, and its principal ingredient is methane (methane), accounts for 83%-89%, it is conventionally believed that methane is exactly coal-mine gas.Gas is first of the disaster of colliery, Safety of Coal Mine Production is threatened maximum.Therefore, be necessary harmful gases such as carbon monoxide and methane are measured simultaneously.Yet the existing means to the harmful gas detection in down-hole are also relatively backward.At first, the existing gas detection in down-hole is to utilize carbon monoxide transducer and methane transducer to measure respectively, does not realize multiple gases integrated sensing and measurement, needs sensor installation and cable more, is unfavorable for adjusting, debugging; Secondly, used sensor mostly is catalytic combustion type or electric chemical formula sensing principle, and the life-span is short, precision is low, poor stability, adjustment difficulty, often exists mistake to survey the wrong report phenomenon.The mistake of colliery harmful gas concentration is surveyed and wrong report, can be transmitted fatal error message, mine and personal security have been constituted very big threat to people.Therefore, in real time, accurately detecting and the overload alarm outage of mine harmful gas concentration, be the major function of coal mine safety monitoring system, also be the important safety guarantee of modernized mine, significant.
Summary of the invention
The objective of the invention is to adopt tunable Distributed Feedback Laser, select the second-harmonic detection of modulation technique and Continuous Wave with frequency modulation (FMCW) technology to combine wavelength, measure when realizing carbon monoxide and concentration of methane gas.
Purpose of the present invention realizes by following scheme: carbon monoxide and methane integral optical fiber sensing measuring system mainly comprise first DFB lasing light emitter, second DFB lasing light emitter, first waveform generator, second waveform generator, first wavelength selection and modulator, second wavelength selection and modulator, fiber coupler, sensing probe, photoelectric conversion module, signal condition and data acquisition module and microprocessor.Connected mode is as follows: first waveform generator produces the continuous sine wave of 100KHz; Acting on first wavelength selects and modulator; First wavelength is selected the spectral modulation scope with first DFB lasing light emitter of modulator control, is adjusted near the absorption spectra of carbon monoxide by certain triangular wave of the 100Hz of threshold voltage partially; In like manner, second waveform generator produces the continuous sine wave of 30KHz, acts on second wavelength and selects and modulator; Second wavelength selected the spectral modulation scope with second DFB lasing light emitter of modulator control, is adjusted near the absorption spectra of methane by certain triangular wave of the 100Hz of threshold voltage partially.
First DFB lasing light emitter is coupled to input end of fiber coupler by the optical fiber connection; Second DFB lasing light emitter connects another input end that is coupled to fiber coupler by optical fiber; The output terminal of coupling mechanism connects sensing probe; Sensing probe connects photoelectric conversion module; Photoelectric conversion module connects signal condition by lead and is connected with data acquisition module; Data acquisition module connects microprocessor by lead; Microprocessor is selected the high-speed dsp microprocessor for use, finishes first and the control of second wavelength selection with modulator, and finishes data acquisition, processing and gas concentration value and calculate.
The present invention utilizes the combination based on the second-harmonic detection of Continuous Wave with frequency modulation (FMCW) technology and wavelength selection modulation technique, measures when realizing carbon monoxide and methane.At first Distributed Feedback Laser is carried out dual waveform modulated, that is: overlapped high-frequency (30KHz or 100KHz) sine wave on the basis of low frequency (100Hz) triangular wave, wherein, the purpose that applies the low frequency triangular modulation is to guarantee that laser instrument goes out the absorption line that optical wavelength can cover the gas of surveying, applying high_frequency sine wave is in order to realize second-harmonic detection, to improve sensitivity; Secondly, the present invention obtains second harmonic (60KHz or 200KHz) data to adopt the method for FFT spectrum analysis through the photosignal of sensing probe, calculates gas concentration.
The spectral range of first DFB lasing light emitter comprises the carbon monoxide absorption spectra.Under first wavelength selection and modulator adjusting, first DFB lasing light emitter sends the narrow band light of continuous strength and wavelength-modulated, its intensity is modulated into the continuous wave that frequency is f1, the scope that its wavelength is selected is near the carbon monoxide absorption spectra and modulate this length scanning, sweep limit covers the absorption spectra of carbon monoxide, and the triangular wave of sweep frequency and selection of first wavelength and modulator is synchronous.Light modulated is absorbed during by the interior sensing probe that measured atmospheric CO arranged, and aims at the wavelength at gas absorption peak when the laser center mean wavelength, and second harmonic signal and signal amplitude that output light includes modulating frequency f1 are proportional to gas concentration.According to this, can calculate the concentration value of carbon monoxide.
In like manner, the spectral range of second DFB lasing light emitter comprises the methane adsorption spectrum, and under second wavelength selection and modulator adjusting, second DFB lasing light emitter sends the narrow band light of continuous strength and wavelength-modulated, and its intensity is modulated into the continuous wave that frequency is f2.In order to differentiate clearly in the spectrum analysis of data processing, f1 and f2 will keep certain frequency poor.The scope that wavelength is selected is near the methane adsorption spectrum and modulate this length scanning, and sweep limit covers the absorption spectra of methane, and the triangular wave of sweep frequency and second wavelength selection and modulator is synchronous.Light modulated is absorbed during by the interior sensing probe that measured gases methane arranged, and aims at the wavelength at gas absorption peak when the laser center mean wavelength, and second harmonic signal and signal amplitude that output light includes modulating frequency f2 are proportional to gas concentration.According to this, can calculate the concentration value of methane.
Because two modulation light wavelengths are all different with frequency, so can the phase mutual interference when in optical fiber, transmitting.The absorption spectra of tested two kinds of atmospheric COs and methane is not overlapping in sensing probe, and only can or not produce crosstalking of transducing signal to its corresponding light modulated generation effect, can realize that the single-point of carbon monoxide and methane is measured simultaneously.In addition, utilize existing sensing network multiplex technique can realize easily that also the carbon monoxide of multiple spot and methane measures simultaneously.
Carbon monoxide that the present invention relates to and methane integral sensing and detection system have its distinct advantages: 1. fiber transmission attenuation is little, can grow Distance Transmission, is suitable for telemeasurement and control; 2. the sensing probe place has only light signal, does not have electric signal, and essential safety is applicable to that the colliery harmful gas detects; 3. the optical fiber volume is little, and is in light weight, flexible, and chemical property is stable, and good electrical insulating property is arranged, and can work reliably under abominable or hazardous environment; 4. be easy to form optical fiber sensing network, realize multi-functional, intelligentized requirement, adopt multiplexing technique, can reduce system cost.
Description of drawings
Fig. 1. carbon monoxide and methane integral optical fiber sensing measuring system schematic diagram
Embodiment
As shown in the figure, carbon monoxide and methane integral optical fiber sensing measuring system mainly comprise first DFB lasing light emitter, second DFB lasing light emitter, first waveform generator, second waveform generator, first wavelength selection and modulator, second wavelength selection and modulator, fiber coupler, sensing probe, photoelectric conversion module, signal condition and data acquisition module and microprocessor.It is characterized in that connected mode is as follows: first waveform generator acts on first wavelength and selects and modulator, and first wavelength is selected and first DFB lasing light emitter of modulator control, and first DFB lasing light emitter connects an input end of coupling mechanism by optical fiber; Second waveform generator acts on second wavelength and selects and modulator, and second wavelength selected and second DFB lasing light emitter of modulator control, and second DFB lasing light emitter connects another input end of coupling mechanism by optical fiber; The output terminal of coupling mechanism connects sensing probe; Sensing probe connects photoelectric conversion module; Photoelectric conversion module connects signal condition and data acquisition module by lead; Data acquisition module connects microprocessor by lead; Microprocessor is controlled first wavelength selection and modulator, second wavelength selection and modulator and display module.
Foregoing carbon monoxide and methane integral optical fiber sensing measuring system is characterized in that the spectral range of first DFB lasing light emitter comprises the absorption spectrum of carbon monoxide, and the spectral range of second DFB lasing light emitter comprises the absorption spectrum of methane.
Foregoing carbon monoxide and methane integral optical fiber sensing measuring system is characterized in that it is the sinusoidal continuous wave of 30KHz that first waveform generator produces sinusoidal continuous wave and second waveform generator generation frequency that frequency is 100KHz.
Foregoing carbon monoxide and methane integral optical fiber sensing measuring system, it is characterized in that first wavelength is selected and modulator generation under the control of DSP microprocessor has certain 100Hz triangular wave of threshold voltage partially, the spectral modulation scope of control lasing light emitter bright dipping is near the absorption spectra 1567nm of carbon monoxide, second wavelength selects to have certain 100Hz triangular wave of threshold voltage partially with modulator generation under the control of DSP microprocessor, and the spectral modulation scope of control lasing light emitter is near the absorption spectra 1665nm of methane.
Foregoing carbon monoxide and methane integral optical fiber sensing measuring system, it is characterized in that it includes a high-speed dsp microprocessor, finish first and the control of second wavelength selection, and finish data acquisition, processing and gas concentration value and calculate with modulator.
The present invention utilizes the combination based on the second-harmonic detection of Continuous Wave with frequency modulation (FMCW) technology and wavelength selection modulation technique, measures when realizing carbon monoxide and methane.
The spectral range of first DFB lasing light emitter comprises the carbon monoxide absorption spectra.The scope that its wavelength of first DFB lasing light emitter is selected is near carbon monoxide absorption spectra 1567nm and modulate this length scanning, sweep limit comprises the absorption spectra 1567nm of carbon monoxide, sweep bandwidth is 0.2nm, and the triangular wave of sweep frequency and selection of first wavelength and modulator is synchronous.Light modulated is absorbed during by the interior sensing probe that measured atmospheric CO arranged, aim at the wavelength at gas absorption peak when the laser center mean wavelength, include in the output light modulating frequency f1 second harmonic signal (2 * f1) and signal amplitude be proportional to gas concentration.
In like manner, the spectral range of second DFB lasing light emitter comprises the methane adsorption spectrum, the scope that its wavelength of second DFB lasing light emitter is selected is near methane adsorption spectrum 1665nm and modulate this length scanning, sweep limit comprises the absorption spectra 1665nm of methane, sweep bandwidth is 0.2nm, sweep frequency and second wavelength select and the triangular wave of modulator synchronous.In order to differentiate clearly in spectrum analysis, f1 and f2 will keep certain frequency poor.Light modulated is absorbed during by the interior sensing probe that measured gases methane arranged, when the laser center mean wavelength is aimed at the wavelength at gas absorption peak, output light include modulating frequency f2 second harmonic signal (2 * f2) and signal amplitude be proportional to gas concentration.
Because two modulation light wavelengths are all different with frequency, so can the phase mutual interference when in optical fiber, transmitting.The absorption spectra of tested two kinds of atmospheric COs and methane is not overlapping in sensing probe, and only can or not produce crosstalking of transducing signal to its corresponding light modulated generation effect, can realize that the single-point of carbon monoxide and methane is measured simultaneously.In addition, utilize existing sensing network multiplex technique can realize easily that also the carbon monoxide of multiple spot and methane measures simultaneously.
After the light signal that sees through sensing probe advanced photoelectric conversion module and sqignal conditioning and data acquisition module, become the digital signal input microprocessor, the Electrosurgical treatment equipment of microprocessor employing DSP2407.Microprocessor carries out the spectrum analysis technique of modern digital signal processing technology to the digital signal of input, extracts the second harmonic signal that frequency is f1 and f2 respectively, and the amplitude of signal is proportional to gas concentration, send demonstration with the gas concentration of calculating.
Claims (1)
- Carbon monoxide and methane integral optical fiber sensing measuring system is characterized in that: system mainly comprises first DFB lasing light emitter, second DFB lasing light emitter, first waveform generator, second waveform generator, first wavelength selection and modulator, second wavelength selection and modulator, fiber coupler, sensing probe, photoelectric conversion module, signal condition and data acquisition module and microprocessor.Connected mode is as follows: first waveform generator produces the continuous sinusoidal spectrum ripple of 100KHz, acts on first wavelength and selects and modulator; First wavelength is selected and first DFB lasing light emitter spectral modulation scope of modulator control, is adjusted near the absorption spectra of carbon monoxide by certain triangular wave of the 100Hz of threshold voltage partially; In like manner, second waveform generator produces the continuous sine wave of 30KHz, acts on second wavelength and selects and modulator; Second wavelength selected and second DFB Laser Power Devices of modulator control modulation range, regulate that by the triangular wave of certain 30KHz of threshold voltage partially spectrum is adjusted near the absorption spectra of methane, first DFB lasing light emitter connects by optical fiber and is coupled to input end of fiber coupler; Second DFB lasing light emitter connects another input end that is coupled to fiber coupler by optical fiber; The output terminal of coupling mechanism connects sensing probe; Sensing probe connects photoelectric conversion module; Photoelectric conversion module connects signal condition by lead and is connected with data acquisition module, and data acquisition module connects microprocessor by lead; Microprocessor is selected the high-speed dsp microprocessor for use, finishes first and the control of second wavelength selection with modulator, and finishes data acquisition, processing and gas concentration value and calculate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100197091A CN100437091C (en) | 2006-07-25 | 2006-07-25 | Carbon monoxide and methane integral optical fiber sensing measuring system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100197091A CN100437091C (en) | 2006-07-25 | 2006-07-25 | Carbon monoxide and methane integral optical fiber sensing measuring system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1888864A true CN1888864A (en) | 2007-01-03 |
| CN100437091C CN100437091C (en) | 2008-11-26 |
Family
ID=37578153
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100197091A Active CN100437091C (en) | 2006-07-25 | 2006-07-25 | Carbon monoxide and methane integral optical fiber sensing measuring system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN100437091C (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101738382A (en) * | 2008-11-14 | 2010-06-16 | 香港理工大学 | Transformer failure gas monitoring system and method |
| CN101799408A (en) * | 2010-01-08 | 2010-08-11 | 山东省科学院激光研究所 | Optical fiber multi-parameter detector for gas power generation |
| CN101251482B (en) * | 2008-03-28 | 2010-10-06 | 山东省科学院激光研究所 | Firedamp remote optical fiber laser detection instrument for mine |
| CN103472016A (en) * | 2013-09-17 | 2013-12-25 | 武汉分析仪器厂 | Spectrophotometric detector for detecting methanal and ammonia in air |
| CN106525734A (en) * | 2016-10-20 | 2017-03-22 | 天津大学 | Imaging device based on triangular wave frequency code for ascending preset level |
| CN108844870A (en) * | 2018-08-08 | 2018-11-20 | 重庆交通大学 | PM based on optical fiber structure10And PM2.5Detection instrument device and system |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2124473U (en) * | 1992-06-05 | 1992-12-09 | 机械电子工业部第二十三研究所 | Optical fibre type co detecting and alarm device |
| DE10063678A1 (en) * | 2000-12-20 | 2002-07-18 | Siemens Ag | Method for the selective detection of gases using laser spectroscopy |
| CN2559981Y (en) * | 2002-02-08 | 2003-07-09 | 武汉理工大学 | Optical fibre gas-sensitive sensing measuring apparatus |
| US6859766B2 (en) * | 2002-02-11 | 2005-02-22 | American Air Liquide, Inc. | Indirect gas species monitoring using tunable diode lasers |
| US7352463B2 (en) * | 2002-09-06 | 2008-04-01 | Tdw Delaware, Inc. | Method and device for detecting gases by absorption spectroscopy |
| CN1544918A (en) * | 2003-11-14 | 2004-11-10 | 上海波汇通信科技有限公司 | Difference absorption type optical fiber methane gas sensors |
| CN1793864A (en) * | 2006-01-17 | 2006-06-28 | 浙江大学 | Methane distribution type sensing method and equipment based on optical fiber Bragg grating |
| CN2935131Y (en) * | 2006-07-25 | 2007-08-15 | 武汉理工大学 | Carbon monoxide and methane integrated optical fiber sensing measurement system |
-
2006
- 2006-07-25 CN CNB2006100197091A patent/CN100437091C/en active Active
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101251482B (en) * | 2008-03-28 | 2010-10-06 | 山东省科学院激光研究所 | Firedamp remote optical fiber laser detection instrument for mine |
| CN101738382A (en) * | 2008-11-14 | 2010-06-16 | 香港理工大学 | Transformer failure gas monitoring system and method |
| CN101738382B (en) * | 2008-11-14 | 2013-09-18 | 香港理工大学 | Transformer failure gas monitoring system and method |
| CN101799408A (en) * | 2010-01-08 | 2010-08-11 | 山东省科学院激光研究所 | Optical fiber multi-parameter detector for gas power generation |
| CN101799408B (en) * | 2010-01-08 | 2011-10-26 | 山东省科学院激光研究所 | Optical fiber multi-parameter detector for gas power generation |
| CN103472016A (en) * | 2013-09-17 | 2013-12-25 | 武汉分析仪器厂 | Spectrophotometric detector for detecting methanal and ammonia in air |
| CN106525734A (en) * | 2016-10-20 | 2017-03-22 | 天津大学 | Imaging device based on triangular wave frequency code for ascending preset level |
| CN108844870A (en) * | 2018-08-08 | 2018-11-20 | 重庆交通大学 | PM based on optical fiber structure10And PM2.5Detection instrument device and system |
| CN108844870B (en) * | 2018-08-08 | 2021-09-21 | 重庆交通大学 | PM based on optical fiber structure10And PM2.5Probe instrument apparatus and system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN100437091C (en) | 2008-11-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100437091C (en) | Carbon monoxide and methane integral optical fiber sensing measuring system | |
| CN2935131Y (en) | Carbon monoxide and methane integrated optical fiber sensing measurement system | |
| CN100545633C (en) | The method and apparatus of laser gas remote measurement | |
| CN100520360C (en) | Opening natural gas leaking multi-channel monitoring method and light path structure | |
| CN101281127A (en) | Instrument and method for real time monitoring optical fibre distributed multi-point mash gas | |
| CN202216902U (en) | Distributed laser methane monitoring system | |
| CN112763454B (en) | Multi-gas sensing system and detection method | |
| WO2014071691A1 (en) | Vcsel-based low-power-consumption gas detection method and device | |
| CN103439291B (en) | A kind of distribution type fiber-optic methane monitoring system based on TDLAS | |
| CN1632485A (en) | Distributed optical fiber grating temperature detection system for high voltage electric power equipment | |
| CN1793864A (en) | Methane distribution type sensing method and equipment based on optical fiber Bragg grating | |
| CN100424495C (en) | Gas differential absorbing monitoring system with fibre-optical and multi-point in mine | |
| CN100507518C (en) | High-performance optical fiber gas sensor | |
| CN108375555A (en) | Optical fiber methane sensing module, optical fiber multiple spot photo-electric methane transducer and system | |
| CN207232005U (en) | Multiplexing fiber-optic gas sensing system based on weak optical fiber Bragg grating and optical time domain reflectometer | |
| CN101825562A (en) | Method for detecting coal mine gas concentration based on dual wavelength laser | |
| CN110702625A (en) | Coal mine spontaneous ignition prevention monitoring system based on optical fiber sensing and laser spectrum analysis | |
| CN101046450B (en) | Fiber grating process and equipment for detecting methane | |
| CN102346133A (en) | Coalmine gas monitoring device and method | |
| CN1888834B (en) | Optical fiber grating sensor wave length measuring system | |
| CN102478510A (en) | Spectrum-type sensor for methane detection | |
| CN1963462A (en) | Laser monitoring system for gas | |
| CN207850903U (en) | Concentration of methane gas detection device | |
| CN2760526Y (en) | Distributed optical fibre raster temperature detecting system | |
| CN102954949A (en) | System with multi-channel networkings for simultaneous monitoring on coal mine gas concentration |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: WUTOS TECHNOLOGY CO., LTD. Free format text: FORMER OWNER: WUHAN UNIVERSITY OF TECHNOLOGY Effective date: 20091225 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20091225 Address after: Hubei city of Wuhan province Wuchang Luoshi Road No. 122 Patentee after: Wuhan Ligong Guangke Co., Ltd. Address before: Luoshi road in Hubei province Wuhan city Hongshan District No. 122 Patentee before: Wuhan University of Technology |