CN105424632B - A kind of micro water vapor detectable concentration method of range automatic control - Google Patents
A kind of micro water vapor detectable concentration method of range automatic control Download PDFInfo
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Abstract
A kind of micro water vapor concentration detection method of range automatic control, belong to gas sensing system detection field, system composition includes single-chip microcomputer, laser temperature control and drive module, Distributed Feedback Laser, air chamber, photodetector, Current Voltage modular converter, lock-in amplifier, precision voltage reference generator, subtracter, gain control module, signal acquisition module.The system is transformed the measurement range selection module of the multichannel preset parameter in traditional secondary Harmonic Method micro water vapor detecting system, after lock-in amplifier obtains the also harmonic amplitude of concentration information, harmonics are controlled using gain control module, and pass through the information exchange between gain control module and signal acquisition module, range automatic control is realized, water vapor concentration under test gas is worth to finally by output harmonic wave amplitude and gain.This method breaks limitation of the concentration range to circuit measuring, expands detecting concentration scope, effectively improves signal to noise ratio, is conducive to extracting gas concentration information.
Description
Technical field
Gas sensing system detection field of the present invention is a kind of while being referred to using high-accuracy voltage, direct current is adjusted and single
The new method that the control of piece machine is gathered to trace amounts of water vapor concentration information.
Background technology
Water is the important substance that we depend on for existence, and detection water vapor concentration is all significant in many fields.For example
Dielectric gas SF in extra-high voltage electric transmission and transformation system equipment6In when containing moisture, toxicity and corrosivity very strong chemicals can be generated
Matter, etching insulative equipment, or even explode.Water content in food-processing industry, packaging bag is exceeded, can directly affect food
Quality.Water content is more in transformer oil, and oily aging itself, apparatus insulated aging and metal parts corrosion rate are faster；
The presence of natural gas reclaimed water can cause pipeline water blocking, and corroded pipeline, instrument and equipment influence the degree of accuracy of gas metering, given
The safety in production of natural gas and using causing high risks.And fiber gas sensor is because its stability is good, measurement accuracy is high, anti-
The advantages of electromagnetic interference, on-line checking, achievable non-electric detection, obtains more and more extensive in the measurement of trace gas concentration
Using.
Nowadays it is the method for quadratic harmonics for measurement micro water vapor most efficient method, belongs to fiber gas sensor
A kind of effectively application, this method measurement accuracy is high, and stability is good, strong antijamming capability.In order to adapt to the vapor of wider range
Measurement of concetration, while system signal noise ratio is further improved, in different concentration ranges, it is necessary to set the different circuit parameter of multichannel
Selective circuit of measuring range, this causes circuit lengthy and jumbled, the wasting of resources, and can introduce more circuits noise.Therefore, in the urgent need to one kind
Simple effective detection method solves the above problems.
Harbin Engineering University Zhang Keke writes paper《Spectral absorption formula fiber-optic fiber gas etection theory and technical research》In
The second-harmonic detection method mentioned is that laser is modulated using first harmonic, the laser signal after gas absworption peak
The signals of a large amount of frequencies of carrying, carrying out secondary frequency Harmonic Detection under secondary reference signal auxiliary using lock-in amplifier can
The signal of other frequency contents is filtered to obtain the secondary singal comprising gas concentration information.The second harmonic eventually detected
The amplitude of signal is relevant with water vapor concentration, as water vapor concentration increases, and linear increase is presented in harmonic amplitude.If do not taken
Corresponding measure, in the moisture concentration detection of wide scope, the harmonic amplitude having under the concentration range of part exceeds acquisition range.
Therefore different circuit parameter processing must be carried out to the vapor under various concentrations, can so causes circuit complicated, conversion trouble,
And other circuit noises are easily introduced, therefore detection ease is restricted.
The content of the invention
In order to overcome the defect and deficiency of prior art, the micro water vapor detection that the present invention provides a kind of range automatic control is dense
Degree method, this method can more simple and convenient and the accurate detection for effectively carrying out water vapor concentration.
The technical scheme of the inventive method is as follows:
A kind of micro water vapor detectable concentration method of range automatic control, is realized, the system includes by following measuring system
Chip Microcomputer A, single-chip microcomputer B, temperature control drive module, Distributed Feedback Laser, air chamber, photodetector, Current Voltage modular converter, lock phase
Amplifier, precision voltage reference generator, subtracter, gain control module and signal acquisition module, temperature control drive module bag
Temperature control module and drive module are included, Chip Microcomputer A connection drive module, temperature control drive module is connected with Distributed Feedback Laser, and DFB swashs
Light device is located at before air chamber, photodetector is placed behind air chamber, photodetector output end is connected to Current Voltage modulus of conversion
The input of block, Current Voltage modular converter output end is connected with lock-in amplifier, and Chip Microcomputer A connects the ginseng of lock-in amplifier
Signal input part is examined, reference signal is provided for lock-in amplifier；Lock-in amplifier is connected with the normal phase input end of subtracter, by locking
The second harmonic that the demodulation of phase amplifier is obtained can send into the normal phase input end of subtracter, precision voltage reference generator and subtraction
The negative input of device is connected, and gain control module is connected between the output end of subtracter and negative input negative anti-to constitute
Connected mode is presented, while gain control module and signal acquisition module are connected with single-chip microcomputer B respectively, to control harmonic amplitude to increase
The backfeed loop of benefit, signal acquisition module often gathers an amplitude, and single-chip microcomputer B controls gain control module is once adjusted,
The data of the harmonic amplitude collected and the yield value of adjustment are inputted computer by single-chip microcomputer B by serial ports simultaneously, and in electricity
Preservation is shown in brain, this method step is as follows：
1) above-mentioned each part is connected, switched on power, debugging light path and circuit can normal works；Open air chamber
Valve, under test gas is injected in air chamber, inflates 20 minutes, it is ensured that without other gas residues in air chamber；
2) scanning signal that Chip Microcomputer A produces primary modulation Signal averaging low frequency inputs drive module as drive signal,
Drive module drives the luminous of Distributed Feedback Laser, while temperature control module controls laser. operating temperature, Chip Microcomputer A also produces one
Frequency is twice in the reference signal input of the secondary reference signal input lock-in amplifier of primary modulation ripple, mutually amplifies for locking
Device frequency-selecting, before formal measurement, oscillograph is connected on respectively drive module output end and lock-in amplifier reference signal input,
Check whether drive signal and reference signal are normal；
3) the laser input air chamber that laser is sent produces absorption, and the optical signal after absorption reaches photodetection through optical fiber
Device, photodetector converts optical signal into current signal, and signal is changed into carrying aqueous vapor by Current Voltage modular converter
The voltage signal of information, Current Voltage modular converter output end connection lock-in amplifier input, lock-in amplifier is for the electricity
Press signal and reference signal to carry out lock phase processor, obtain including the second harmonic signal of moisture concentration information；
4) for ensure second harmonic signal in the collectable scope of signal acquisition module, it is necessary to lock-in amplifier export
Harmonic signal carry out DC offset voltage adjustment, lock-in amplifier output end connect subtracter normal phase input end, high accuracy
The negative input of pedestal generator connection subtracter provides high-accuracy stable voltage for subtracter, by adjusting high accuracy
The voltage swing that pedestal generator is produced, adjustment participates in the DC voltage size of subtracter computing, reaches adjustment harmonic wave letter
The purpose of number DC offset voltage；
5) input of the second harmonic signal entering signal acquisition module exported by subtracter, signal acquisition module is to two
Subharmonic carries out amplitude collection, just can obtain carrying the harmonic amplitude of moisture concentration information, signal acquisition module and single-chip microcomputer B phases
Even, harmonic amplitude by signal acquisition module export after input single-chip microcomputer B, the program of pre-set control gain in single-chip microcomputer B,
And harmonic amplitude scope is specified, single-chip microcomputer B makes comparisons the harmonic amplitude of collection with setting range, if harmonic amplitude is in setting
Within the scope of, then it is not required to adjustment；Harmonic amplitude is if greater than setting range maximum, and gain control module can control to reduce gain
Value, harmonics reduce, and amplitude declines；If harmonic amplitude is less than setting range minimum value, gain control module can control to increase
Large gain values, harmonics increase, amplitude becomes big；The harmonic wave being adjusted will be again introduced into signal acquisition module, repeat above-mentioned
Process, often through once adjusting, single-chip microcomputer B is defeated by serial ports by the data of the harmonic amplitude collected and the yield value of adjustment
Enter computer, and preservation is shown in computer, by the data of display, script harmonic amplitude is reduced, and then it is dense to obtain vapor
Degree；
6) the moisture concentration detection of under test gas is finished, and closes power supply.
The Cleaning Principle that the present invention is used such as Harbin Engineering University Zhang Keke writes paper《Spectral absorption fiber-optic fiber gas is examined
Survey theoretical and technical research》Described, at one atm, the absorption of vapor can linearly be represented by lorentzian curve, red
Wave section, the absorption coefficient of vapor is smaller, and the output intensity of normal atmosphere pressure is represented by：
I (v)=I0(v)[1-α(v)CL] (1)
α (υ) is gas in the absorption coefficient that light frequency is at υ in formula, and L is light path of the light by under test gas, and C is to be measured
The volumetric concentration of gas.The temperature and direct driving current of laser are adjusted, it is to be scheduled on a certain suction of vapor to make optical maser wavelength
Receive at peak.Then, the sinusoidal signal of appropriate frequency and amplitude is superimposed in the driving current signal of laser, to the ripple of laser
Length is modulated, and it is changed at absworption peak by sinusoidal rule, laser instantaneous output is：
(t)=vc+Δνcosωt (2)
Δ ν is modulation amplitude in formula, and ω is modulation angular frequency, νcFor filters center frequency.Laser wavelength is stable
At absorbent core, that is, there is νc=ν0, normalized frequency skew x can be represented using line half-width γ and instantaneous frequency ν
In formula：x0=(νc-ν0)/γ；M=Δs ν/γ is the wavelength index of modulation.After being absorbed by gas, what is detected is defeated
Going out signal is
S (x)=I (x)=I (x0+mcosωt) (4)
Fourier expansion is carried out to (4), direct current and 1, the expression formula of 2,3 subharmonic, for warbled Lip river is can obtain
Human relations hereby for line style, contain the concentration letter of under test gas in the even harmonics signal amplitude at the centre frequency of Absorption Line
Breath, available for measurement gas concentration.Water vapor concentration is bigger, and harmonic amplitude can be higher.But the maximum of each even harmonics signal
Amplitude reduces with the increase of overtone order, only even-order harmonic and second harmonic signal be it is most strong in each harmonic, two
Subharmonic expression formula is as follows
In formula：X=1-x2+m2；
The signal of other frequencies of the target signal filter of second harmonic frequency is locked using Phase Lock Technique, second harmonic is detected, if
Now secondary harmonic amplitude is A.Because the second harmonic signal demodulated is without direct current biasing, DC reference voltage is added, will
Second harmonic is adjusted in the collectable scope of signal acquisition module, and DC reference voltage does not change second harmonic width
Value, it is assumed that direct current adjustment reference voltage is M, and output voltage now is
S′2(x)=S2(x)+M (6)
Now second harmonic S '2(x) amplitude is still in A, the concentration range of different ranges, to make secondary harmonic amplitude same
One scope is, it is necessary to be amplified multiple adjustment, it is assumed that p times of signal intensity, then now output signal is
S″2(x)=p [S2(x)+M] (7)
The secondary harmonic amplitude collected is pA, in the signal processing, will be secondary humorous by permanent circuit parameters relationship
Wave amplitude is reduced, you can obtain water vapor concentration information.
Second harmonic measurement range selection part is the fortune by different amplification in traditional micro water vapor detecting system
Circuit realiration is put, measurement range selection scope is small, parameter setting is complicated, troublesome poeration, and circuit is lengthy and jumbled, and noise is big.The present invention
Gain control module is added, the part adjusted as harmonic signal gain factor, by single-chip microcomputer control, passes through signal acquisition mould
The backfeed loop of block-single-chip microcomputer-gain control module formation control harmonics, monitors secondary harmonic amplitude, while fast in real time
The whole yield value of velocity modulation so that harmonic amplitude is in the acquisition range of setting, and final water vapor concentration information is by adopting to obtain second harmonic
Amplitude is together decided on yield value.This method breaks traditions the limitation of circuit measurement range selection, no matter moisture concentration size, gain adjusts
Mould preparation block in acquisition range, expands moisture concentration measurement range by harmonic amplitude adjustment.The circuit system is more succinctly stablized,
Signal-to-Noise is effectively improved, and the performance boost for micro water vapor Concentration Testing has very great help.
Brief description of the drawings
Fig. 1 be the present invention realize system construction drawing.
Wherein：1st, Chip Microcomputer A, 2, temperature control drive module, 3, Distributed Feedback Laser, 4, air chamber, 5, photodetector, 6, electric current
Voltage transformation module, 7, lock-in amplifier, 8, subtracter, 9, gain control module, 10, precision voltage reference generator, 11,
Signal acquisition module, 12, single-chip microcomputer B, 13, the reference signal of lock-in amplifier, 14, drive signal.
Fig. 2 is that the drive signal that single-chip microcomputer is sent is transferred to drive module to drive laser to light, and the waveform is by height
What frequency sine-wave Signal averaging was obtained in low frequency trapezoidal wave scanning signal.
The harmonic signal that Fig. 3 obtains for detection, the amplitude of harmonic signal also has the information of moisture concentration, therefore collection harmonic wave
Amplitude just can obtain moisture concentration.
Embodiment
The invention will be further described with reference to the accompanying drawings and examples, but not limited to this.
Embodiment：
As shown in figure 1, a kind of micro water vapor detectable concentration method of range automatic control, is realized by following measuring system,
The system includes Chip Microcomputer A, B, temperature control drive module 2, Distributed Feedback Laser 3, air chamber 4, photodetector 5, Current Voltage modulus of conversion
Block 6, lock-in amplifier 7, subtracter 8, gain control module 9, precision voltage reference generator 10 and signal acquisition module 11,
Temperature control drive module 2 includes temperature control module and drive module, Chip Microcomputer A connection drive module, temperature control drive module and DFB laser
Device 3 is connected, and Distributed Feedback Laser 3 is located at before air chamber 4, and air chamber 4 places photodetector 5, the output end of photodetector 5 below
The input of Current Voltage modular converter 6 is connected to, the output end of Current Voltage modular converter 6 is connected with lock-in amplifier 7, it is single
The reference signal input of piece machine A connections lock-in amplifier 7, is that lock-in amplifier 7 provides reference signal；Lock-in amplifier 7 with
The normal phase input end of subtracter 8 is connected, and the positive that the second harmonic obtained by the demodulation of lock-in amplifier 7 can send into subtracter 8 is defeated
Enter end, precision voltage reference generator 10 is connected with the negative input of subtracter 8, and gain control module 9 is connected to subtraction
To constitute negative-feedback connected mode between the output end and negative input of device 8, while gain control module 9 and signal acquisition mould
Block 11 is connected with single-chip microcomputer B respectively, and to control the backfeed loop of harmonic amplitude gain, signal acquisition module often gathers once width
Value, single-chip microcomputer B controls gain control module is once adjusted, while single-chip microcomputer B is by the harmonic amplitude collected and tune
The data of whole yield value input computer by serial ports, and show in computer preservation, and this method step is as follows：
1) above-mentioned each part is connected, switched on power, debugging light path and circuit can normal works；Open air chamber
Valve, under test gas is injected in air chamber, inflates 20 minutes, it is ensured that without other gas residues in air chamber；
2) scanning signal that Chip Microcomputer A produces primary modulation Signal averaging low frequency inputs drive module as drive signal,
Drive module drives the luminous of Distributed Feedback Laser, while temperature control module controls laser. operating temperature, Chip Microcomputer A also produces one
Frequency is twice in the reference signal input of the secondary reference signal input lock-in amplifier of primary modulation ripple, mutually amplifies for locking
Device frequency-selecting.Before formal measurement, oscillograph is connected on to drive module output end and lock-in amplifier reference signal input respectively,
Check whether drive signal and reference signal are normal；
3) the laser input air chamber that laser is sent produces absorption, and the optical signal after absorption reaches photodetection through optical fiber
Device, converts optical signal into current signal, and signal is changed into the voltage for carrying aqueous vapor information by Current Voltage modular converter
Signal, Current Voltage modular converter output end connection lock-in amplifier input, lock-in amplifier is for the voltage signal and ginseng
Examine signal and carry out lock phase processor, obtain including the second harmonic signal of moisture concentration information；
4) for ensure second harmonic signal in the collectable scope of signal acquisition module, it is necessary to lock-in amplifier export
Harmonic signal carry out DC offset voltage adjustment, lock-in amplifier output end connect subtracter normal phase input end, high accuracy
The negative input of pedestal generator connection subtracter provides high-accuracy stable voltage for subtracter, by adjusting high accuracy
The voltage swing that pedestal generator is produced, adjustment participates in the DC voltage size of subtracter computing, reaches adjustment harmonic wave letter
The purpose of number DC offset voltage；
5) input of the second harmonic signal entering signal acquisition module exported by subtracter, signal acquisition module is to two
Subharmonic carries out amplitude collection, just can obtain carrying the harmonic amplitude of moisture concentration information, signal acquisition module and single-chip microcomputer B phases
Even, harmonic amplitude by signal acquisition module export after input single-chip microcomputer B, the program of pre-set control gain in single-chip microcomputer B,
And harmonic amplitude scope is specified, single-chip microcomputer B makes comparisons the harmonic amplitude of collection with setting range, if harmonic amplitude is in setting
Within the scope of, then it is not required to adjustment；Harmonic amplitude is if greater than setting range maximum, and gain control module can control to reduce gain
Value, harmonics reduce, and amplitude declines；If harmonic amplitude is less than setting range minimum value, gain control module can control to increase
Large gain values, harmonics increase, amplitude becomes big；The harmonic wave being adjusted will be again introduced into signal acquisition module, repeat above-mentioned
Process, often through once adjusting, single-chip microcomputer B is defeated by serial ports by the data of the harmonic amplitude collected and the yield value of adjustment
Enter computer, and preservation is shown in computer, by the data of display, script harmonic amplitude is reduced, and then it is dense to obtain vapor
Degree；
6) the moisture concentration detection of under test gas is finished, and closes power supply.
Claims (1)
1. a kind of micro water vapor detectable concentration method of range automatic control, is realized by following measuring system, the system includes single
Piece machine A, single-chip microcomputer B, temperature control drive module, Distributed Feedback Laser, air chamber, photodetector, Current Voltage modular converter, lock are mutually put
Big device, precision voltage reference generator, subtracter, gain control module and signal acquisition module, temperature control drive module include
Temperature control module and drive module, Chip Microcomputer A connection drive module, temperature control drive module are connected with Distributed Feedback Laser, DFB laser
Device is located at before air chamber, photodetector is placed behind air chamber, photodetector output end is connected to Current Voltage modular converter
Input, Current Voltage modular converter output end is connected with lock-in amplifier, and Chip Microcomputer A connects the reference of lock-in amplifier
Signal input part, reference signal is provided for lock-in amplifier；Lock-in amplifier is connected with the normal phase input end of subtracter, by lock phase
The second harmonic that amplifier demodulation is obtained can send into the normal phase input end of subtracter, precision voltage reference generator and subtracter
Negative input be connected, gain control module is connected between the output end of subtracter and negative input to constitute negative-feedback
Connected mode, while gain control module and signal acquisition module are connected with single-chip microcomputer B respectively, to control harmonic amplitude gain
Backfeed loop, signal acquisition module often gathers an amplitude, and single-chip microcomputer B controls gain control module is once adjusted, together
When single-chip microcomputer B the data of the harmonic amplitude collected and the yield value of adjustment are inputted into computer by serial ports, and in computer
Middle display is preserved, and this method step is as follows：
1) above-mentioned each part is connected, switched on power, debugging light path and circuit can normal works；Open air-chamber valve
Door, under test gas is injected in air chamber, inflates 20 minutes, it is ensured that without other gas residues in air chamber；
2) scanning signal that Chip Microcomputer A produces primary modulation Signal averaging low frequency inputs drive module, driving as drive signal
Module drive Distributed Feedback Laser it is luminous, while temperature control module controls laser. operating temperature, Chip Microcomputer A also produces a frequency
The secondary reference signal for being twice in primary modulation ripple inputs the reference signal input of lock-in amplifier, for lock-in amplifier choosing
Frequently, before formal measurement, oscillograph is connected on to drive module output end and lock-in amplifier reference signal input respectively, checked
Whether drive signal and reference signal are normal；
3) the laser input air chamber that laser is sent produces absorption, and the optical signal after absorption reaches photodetector, light through optical fiber
Electric explorer converts optical signal into current signal, is changed into signal by Current Voltage modular converter and carries aqueous vapor information
Voltage signal, Current Voltage modular converter output end connection lock-in amplifier input, lock-in amplifier is for the voltage signal
Lock phase processor is carried out with reference signal, obtains including the second harmonic signal of moisture concentration information；
4) for ensure second harmonic signal in the collectable scope of signal acquisition module, it is necessary to lock-in amplifier export it is humorous
Ripple signal carries out DC offset voltage adjustment, and lock-in amplifier output end connects the normal phase input end of subtracter, high precision reference
The negative input of voltage generator connection subtracter provides high-accuracy stable voltage for subtracter, by adjusting high precision reference
The voltage swing that voltage generator is produced, adjustment participates in the DC voltage size of subtracter computing, reaches that adjustment harmonic signal is straight
Flow the purpose of bias voltage；
5) input of the second harmonic signal entering signal acquisition module exported by subtracter, signal acquisition module is to secondary humorous
Ripple carries out amplitude collection, just can obtain carrying the harmonic amplitude of moisture concentration information, and signal acquisition module is connected with single-chip microcomputer B,
Harmonic amplitude by signal acquisition module export after input single-chip microcomputer B, the program of pre-set control gain in single-chip microcomputer B, and
Harmonic amplitude scope is specified, single-chip microcomputer B makes comparisons the harmonic amplitude of collection with setting range, if harmonic amplitude is in setting model
Within enclosing, then adjustment is not required to；Harmonic amplitude is if greater than setting range maximum, and gain control module can control to reduce gain
Value, harmonics reduce, and amplitude declines；If harmonic amplitude is less than setting range minimum value, gain control module can control to increase
Large gain values, harmonics increase, amplitude becomes big；The harmonic wave being adjusted will be again introduced into signal acquisition module, repeat above-mentioned
Process, often through once adjusting, single-chip microcomputer B is defeated by serial ports by the data of the harmonic amplitude collected and the yield value of adjustment
Enter computer, and preservation is shown in computer, by the data of display, script harmonic amplitude is reduced, and then it is dense to obtain vapor
Degree；
6) the moisture concentration detection of under test gas is finished, and closes power supply.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5267019A (en) * | 1991-09-30 | 1993-11-30 | Consortium For Surface Processing, Inc. | Method and apparatus for reducing fringe interference in laser spectroscopy |
| US8149407B1 (en) * | 2010-09-09 | 2012-04-03 | Adelphi University | Method and apparatus for trace gas detection using off-axis cavity and multiple line integrated spectroscopy |
| CN102495021A (en) * | 2011-12-12 | 2012-06-13 | 山东大学 | System and method for detecting trace amount of steam based on two absorption peaks |
| CN103472003A (en) * | 2013-09-27 | 2013-12-25 | 山东大学 | Novel method used for phase lock voltage subtraction of micro water vapor detection |
| CN104535530A (en) * | 2014-12-05 | 2015-04-22 | 山东省科学院海洋仪器仪表研究所 | High-precision gas concentration detection method and detection apparatus thereof |
| CN104698275A (en) * | 2015-03-28 | 2015-06-10 | 山东大学 | System for generating small-angle phase shifting and detecting |
-
2015
- 2015-12-29 CN CN201511019511.9A patent/CN105424632B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5267019A (en) * | 1991-09-30 | 1993-11-30 | Consortium For Surface Processing, Inc. | Method and apparatus for reducing fringe interference in laser spectroscopy |
| US8149407B1 (en) * | 2010-09-09 | 2012-04-03 | Adelphi University | Method and apparatus for trace gas detection using off-axis cavity and multiple line integrated spectroscopy |
| CN102495021A (en) * | 2011-12-12 | 2012-06-13 | 山东大学 | System and method for detecting trace amount of steam based on two absorption peaks |
| CN103472003A (en) * | 2013-09-27 | 2013-12-25 | 山东大学 | Novel method used for phase lock voltage subtraction of micro water vapor detection |
| CN104535530A (en) * | 2014-12-05 | 2015-04-22 | 山东省科学院海洋仪器仪表研究所 | High-precision gas concentration detection method and detection apparatus thereof |
| CN104698275A (en) * | 2015-03-28 | 2015-06-10 | 山东大学 | System for generating small-angle phase shifting and detecting |
Non-Patent Citations (5)
| Title |
|---|
| Dual-beam wavelength modulation spectroscopy for sensitive detection of water vapor;Qiang Wang,et al.;《Appl. Phys. B》;20140913;第117卷;1015-1023 * |
| Immunity to Laser Power Variation in a DFB Diode Laser Based Optical Gas Sensor Using a Division Process;Hengtai Chang,et al.;《Sensors》;20150422;第15卷;9582-9591 * |
| Single-beam water vapor detection system with automatic photoelectric conversion gain control;C.G. Zhu,et al.;《Optics Communications》;20140602;第331卷;45-52 * |
| Wavelength modulation spectroscopy with signal–reference beam method for highly sensitive gas detection;Wei Wei,et al.;《Appl. Phys. B》;20141105;第118卷;75-83 * |
| 一种基于TDLAS谐波探测技术的甲烷传感器;陈玖英 等;《大气与环境光学学报》;20070331;第2卷(第2期);146-149 * |
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