CN106290247B - Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced - Google Patents
Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced Download PDFInfo
- Publication number
- CN106290247B CN106290247B CN201610836076.7A CN201610836076A CN106290247B CN 106290247 B CN106290247 B CN 106290247B CN 201610836076 A CN201610836076 A CN 201610836076A CN 106290247 B CN106290247 B CN 106290247B
- Authority
- CN
- China
- Prior art keywords
- cavity
- light
- optical resonator
- electromagnetically induced
- splitting prism
- 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.)
- Active
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/39—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using tunable lasers
Landscapes
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Analytical Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Optics & Photonics (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The present invention relates to a kind of continuous wave-cavity ring-down spectroscopy device and methods based on the transparent effect of electromagnetically induced.The device includes: semiconductor laser, light source of the semiconductor laser as detection light and control light, the front cavity mirror of optical resonator, the Effect of Back-Cavity Mirror of the first polarization splitting prism, electromagnetically induced transparent medium gas chamber, the second polarization splitting prism, sample to be tested gas chamber, optical resonator, and the photodetector for receiving detection optical signal are successively arranged in the detection light optical path of its outgoing.The transparent effect of present invention combination electromagnetically induced and Research on Cavity Ring Down Spectroscopy, the high effect of dispersion of distinctive zero absorption of the transparent effect of electromagnetically induced is used for slowing down for intracavitary photon speed, extend photon lifetime, the interaction time for increasing photon and sample, to greatly improve the sensitivity of cavity ring-down spectroscopy.It is simple with structure, the features such as convenient easy-adjustable section, good compatibility.
Description
Technical field
Company the invention belongs to continuous wave Research on Cavity Ring Down Spectroscopy, in particular under a kind of transparent effect based on electromagnetically induced
Continuous wave cavity ring-down spectroscopy device and method, the device and method can be used for the field of precision measurement such as trace gas quantitative analysis.
Background technique
The quantitative analysis of trace gas is all extremely important in many fields, for example, spectroscopy, chemical analysis, medical diagnosis,
Pollutant catabolic gene energy in environmental monitoring and industrial production.For example, with the rapid development of semiconductor technology, semiconductor production mistake
Gas purity needed for journey requires to be continuously improved, and impurities maximum concentration reduces four magnitudes or more.Ultra-high purity
Gas has extremely important effect to smaller and smaller geometrical characteristic required in semiconductor integrated circuit, so semiconductor
Wherein water rate content cannot be greater than 1 × 10 for manufacturing process requirement-9, therefore the requirement to gasmetry sensitivity and precision will not
It is disconnected to improve.
Cavity ring-down spectroscopy (CRDS:Cavity Ringdown Spectroscopy) (Cavity ring-down
optical spectrometer for absorption measurements using pulsed laser sources”,
REVIEW OF SCIENTIFIC INSTRUMENTS, Vol.QE-59, No.12,1988) technology is fast-developing to rise for nearly 30 years
A kind of novel absorbent spectrum detection technique come, with high sensitivity and resolution ratio, and not by light source light-intensity variation
It influences.Since O ' Keefe and Deacon in 1988 are put forward for the first time with cavity ring-down spectroscopy, various Research on Cavity Ring Down Spectroscopy schemes
All once be suggested and apply, they with their own characteristics, complement each other.For example, according to the laser light source type of selection, cavity ring-down spectroscopy
Technology can be divided into impulse type and two kinds of continuous light wave type.Wherein, continuous wave as light source Research on Cavity Ring Down Spectroscopy and by section
The favor of skilled worker author is the preferred option for being commercialized high-precision gas analyzer in the world at present.Usual this technology all needs
An optical resonator with very high-quality-factor is wanted, however when chamber reaches very high quality, it is desirable to continue to improve, it is required
Want technical difficulty and cost very big, and when while realizing very high chamber quality factor, the reflectivity of hysteroscope also can
It is very big.At this point, detection light will be difficult to couple into chamber, coupling efficiency can be very low, this will will lead to detection optical signal
Signal-to-noise ratio can very little, cannot be detected by detector.In order to improve the above problem, its signal-to-noise ratio is improved.1999
D.Romanini et al. proposes a kind of folding and declines and swing chamber scheme, and this scheme is named as light reaction type Research on Cavity Ring Down Spectroscopy
(Optical feedback cavity ring-down spectroscopy)(Measurement of trace gases
by diode laser cavity ringdown spectroscopy”,PROCEEDING OF SPIE-THE
INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING,Vol.3821,1999).The program can be sufficiently sharp
The characteristics of with optical resonator modeling, using its resonant feedback semaphore lock laser frequency and narrows laser line, so that light
The stability of spectra system and the signal-to-noise ratio of cavity-type BPM signal greatly enhance.But this scheme needs to change traditional optical resonance
Chamber is needed 3 hysteroscopes, it is larger to be built difficulty using a v-shaped cavity.
Summary of the invention
It is an object of the invention to overcome the deficiencies of the prior art and provide a kind of based on the continuous of the transparent effect of electromagnetically induced
Wave cavity ring-down spectroscopy device and method.
The purpose of the present invention is achieved through the following technical solutions:
The first aspect of the present invention is to provide a kind of continuous wave-cavity ring-down spectroscopy dress based on the transparent effect of electromagnetically induced
It sets, comprising:
Semiconductor laser, light source of the semiconductor laser as detection light and control light,
The front cavity mirror, the first polarization splitting prism, electromagnetically induced that optical resonator is successively arranged in its detection light optical path being emitted are transparent
The Effect of Back-Cavity Mirror of medium gas chamber, the second polarization splitting prism, sample to be tested gas chamber, optical resonator, and for receiving detection light
The photodetector of signal；
The front cavity mirror of the optical resonator and the Effect of Back-Cavity Mirror composition of optical resonator decline and swing chamber；
The optical resonator Effect of Back-Cavity Mirror is equipped with piezoelectric ceramics, and the piezoelectric ceramics is connected with signal generator, described
Signal generator provides voltage signal for the piezoelectric ceramics；
The control light is reflected into that optical resonance is intracavitary, and the control light passes through by first polarization splitting prism
It adjusts it to polarize so that it is reflected at first polarization splitting prism and second polarization splitting prism, the control light
When by electromagnetically induced transparent medium gas chamber, intersecting for an angle, θ is formed with the detection light, two-beam is in intersection
The transparent effect of electromagnetically induced is constructed, then the control light passes through second polarization splitting prism again and reflects optical resonance
Chamber avoids it in cavity circulation；
Further, the angle, θ range is at 0~2 °, by adjusting the incident first polarization spectro rib of control light
The position of mirror and angle control it.
Further, the optical resonator be it is symmetrical stablize cavity configuration, Asymmetric Stable cavity configuration, v-shaped cavity structure or
Ring cavity structure；Preferably, the optical resonator is confocal cavity.
Further, the back cavity specular reflectivity of the front cavity mirror of the optical resonator and optical resonator is all larger than
99.5%, and the higher the better.
Further, two end faces of the electromagnetically induced transparent medium gas chamber are covered with anti-reflection film, intracavitary for reducing
Loss.
Further, the electromagnetically induced transparent medium is the atoms such as rubidium, sodium or caesium.
Further, first polarization splitting prism and the second polarization splitting prism are used to that the control light to be made to reflect,
The detection light transmission.
The second aspect of the present invention is to provide a kind of to be declined using the above-mentioned continuous wave-cavity based on the transparent effect of electromagnetically induced
Swing the method that spectral device measures, comprising:
A. the selection of lightwave signal
Its intensity is selected and adjusted to the wavelength and frequency of detection light and control light, makes it in transparent Jie of electromagnetically induced
The transparent effect of electromagnetically induced is constructed in matter gas chamber, realizes zero absorption and light speed reduction to detection light；
B. lightwave signal enters optical resonator and reflects in intracavitary formation
B1) detection light is after the front cavity mirror of optical resonator enters optical resonator, due to polarization relation, first full impregnated mistake
Then first polarization splitting prism passes through electromagnetically induced transparent medium gas chamber, using the second polarization splitting prism, pass through sample
Reach the Effect of Back-Cavity Mirror of optical resonator after gas chamber, most of light can reflect back and in cavity circulation, sub-fraction light meeting at this time
Optical resonator is transmitted to be received by photodetector；
B2) it is intracavitary by the first polarization splitting prism to be reflected into optical resonance for control light, and control light is inclined by adjusting it
So that it is reflected at the first polarization splitting prism and the second polarization splitting prism, control light is passing through transparent Jie of electromagnetically induced for vibration
When matter gas chamber, intersecting for an angle, θ is formed with detection light, two-beam constructs the transparent effect of electromagnetically induced in intersection, so
Control light passes through the second polarization splitting prism again and reflects optical resonator afterwards, avoids it in cavity circulation；
C. the processing analysis of lightwave signal
C1. signal generator output triangle wave voltage driving signal is applied on piezoelectric ceramics, scans optical resonator
Length, the longitudinal mode position of chamber can also scan back and forth therewith at this time, when chamber longitudinal mode position is overlapped with detection light frequency, detect optocoupler
It closes into optical resonator and forms stable resonance intracavitary；
C2. photodetector receives the detection optical signal transmitted from the Effect of Back-Cavity Mirror of optical resonator, measures do not put first
Enter transmission spectrum when sample gas chamber, the i.e. transmission spectrum of cavity, sample to be tested is then put into the transmission that sample gas chamber measures sample
Spectrum；
D. transmission spectrum is analyzed by computer and obtains the ring-down time of cavity and sample, the concentration of sample is then calculated
Or type.
Further, the wavelength and frequency of described pair of detection light and control light are selected and adjust its intensity, specifically
Refer to: the detection light and control light determine its wavelength and frequency according to the level structure of the electromagnetically induced transparent medium of selection, and
And it is locked in the building transparent required energy level transition of electromagnetically induced, while detecting light and controlling the intensity of light according to electromagnetically induced
Transparent effect and the detection limit of photodetector do specific adjustment, detect light letter guaranteeing that photodetector can detect
Under the premise of number, detection luminous intensity should be much smaller than control luminous intensity, and controlling luminous intensity can be by measuring with Conditions Sample feelings
Ring-down time under condition optimizes, and chooses intensity when ring-down time longest.
Further, the step d, specifically includes:
Due to using continuous light laser as light source here, and without using Threshold Detection method, so detection light exists
Resonant cavity can be all injected during entire transmission peaks, needs to be handled transmission peaks to eliminate the shadow of detection light whole process injection
It rings.Specific step is as follows, makes the symmetrical curve in transmission peaks forward position using transmission peaks peak position as symmetry axis first, then with saturating
It penetrates behind peak along the symmetrical curve is subtracted, obtains new curve, then with exponential equation: y=y0+ Aexp (Rx), is fitted new curve
Rear edge.According to the definition of ring-down time, i.e. intensity is reduced to the time required when the 1/e of maximum intensity, can pass through fitting
Curve out obtains the ring-down time of cavity and sample, and specific ring-down time can indicate are as follows:
Y=y0+Aexp(Rx)
Wherein, x is the abscissa of new peak of curve；y0, A and R are the constant terms in fit equation.
The present invention utilize the transparent effect of electromagnetically induced, swing intracavitary additions electromagnetically induced transparent medium declining, detection light with
By medium and when reaching resonance, electromagnetically induced transparent medium embodies to detection light zero absorption and has one control light
Very big dispersion, this great dispersion are used to slow down the photon speed of detection light, extend photon in the intracavitary service life, increase
The time of photon and sample interaction, improve the sensitivity of detection light.
The present invention adds a branch of control light, by polarization splitting prism introduce electromagnetically induced transparent medium gas chamber (PBS:
Polarization Beam Splitter), and intersect in gas chamber with detection light low-angle, two light construct electricity in intersection
Then the transparent effect of Magnetic guidance controls light and passes through polarization splitting prism again and reflect to decline and swings chamber, in order to avoid in cavity circulation.
The present invention decline swing in chamber Effect of Back-Cavity Mirror add piezoelectric ceramics (PZT:Piezoelectric Transducer), pass through
Signal generator controls piezoelectric ceramics plus the voltage with triangular signal, controls it and stretches, realization swings chamber to declining
Chamber length be scanned.And pass through adjustment signal generator, it can be achieved that change to chamber frequency and amplitude is swept.
Compared with prior art, the positive effect of the present invention is as follows:
For the deficiency in previous continuous wave cavity-type BPM chamber scheme, the present invention proposes a kind of transparent based on electromagnetically induced
Continuous wave-cavity ring-down spectroscopy technical side on the basis of (EIT:Electromagnetically Induced Transparency)
Case.The present invention utilizes electromagnetically induced by introducing electromagnetically induced transparent medium in initial continuous wave Research on Cavity Ring Down Spectroscopy
The characteristic of transparent effect, when detecting light and control light meets resonance, medium will appear very big dispersion and zero absorption to detection light
Property, great dispersion can significantly improve the refractive index of medium, slow down speed of the photon in medium, to realize extension
Intracavitary photon lifetime increases the time of photon and sample interaction, can effectively improve the sensitivity of detection light.It is more important
Be that this technology also can be good at being compatible with all kinds of cavity ring-down spectroscopy schemes, can be further improved its detectivity.
The transparent effect of present invention combination electromagnetically induced and Research on Cavity Ring Down Spectroscopy, by the distinctive of the transparent effect of electromagnetically induced
The high effect of dispersion of zero absorption slows down for intracavitary photon speed, extends photon lifetime, increases the interaction of photon and sample
Time, to greatly improve the sensitivity of cavity ring-down spectroscopy.It is simple with structure, the features such as convenient easy-adjustable section, good compatibility.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of the continuous wave-cavity ring-down spectroscopy device of the invention based on the transparent effect of electromagnetically induced；
Wherein, light -1 is detected, light -2, front cavity mirror -3, the first polarization splitting prism -4 of optical resonator are controlled, electromagnetism lures
Lead transparent medium gas chamber -5, the second polarization splitting prism -6, sample to be tested gas chamber -7, the Effect of Back-Cavity Mirror -8 of optical resonator, photoelectricity
Detector -9, piezoelectric ceramics -10, signal generator -11；
Fig. 2 is that chamber transmits spectral line data processing schematic；Wherein, a is that there are the chamber transmission spectrums of the transparent effect of electromagnetically induced；
Vertical dotted line is the peak position of transmission peaks in b, as symmetry axis, makes the symmetrical curve of transmission rising edge, as c institute
Show；D is that transmission peaks failing edge subtracts the new curve after rising edge symmetrical curve；
Fig. 3 is change curve of the ring-down time with sample atoms number.
Specific embodiment
Present invention will be further explained below with reference to specific examples.It should be understood that these embodiments are merely to illustrate the present invention
Rather than it limits the scope of the invention.In addition, it should also be understood that, after reading the content taught by the present invention, those skilled in the art
Member can make various changes or modifications the present invention, and such equivalent forms equally fall within the application the appended claims and limited
Range.
Embodiment
As shown in Figure 1, a kind of continuous wave-cavity ring-down spectroscopy device based on the transparent effect of electromagnetically induced of the invention, packet
It includes:
Semiconductor laser, light source of the semiconductor laser as detection light 1 and control light 2, at it
The front cavity mirror 3, the first polarization splitting prism 4, electromagnetically induced that optical resonator is successively arranged in detection 1 optical path of light of outgoing are transparent
The Effect of Back-Cavity Mirror 8 of medium gas chamber 5, the second polarization splitting prism 6, sample to be tested gas chamber 7, optical resonator, and for receiving spy
Survey the photodetector 9 of 1 signal of light；
The front cavity mirror 3 of optical resonator and the composition of Effect of Back-Cavity Mirror 8 of optical resonator decline and swing chamber；The front cavity mirror of optical resonator
3 and 8 reflectivity of Effect of Back-Cavity Mirror of optical resonator be all larger than 99.5%.
Optical resonator Effect of Back-Cavity Mirror 3 is equipped with piezoelectric ceramics 10, and piezoelectric ceramics 10 is connected with signal generator 11, signal hair
Raw device 11 is that piezoelectric ceramics 10 provides voltage signal；
It is intracavitary that control light 2 by the first polarization splitting prism 4 is reflected into optical resonance, and control light 1 is by adjusting it partially
Vibration is so that it is reflected at the first polarization splitting prism 4 and the second polarization splitting prism 6, and control light 1 is saturating by electromagnetically induced
When bright medium gas chamber, intersecting for an angle, θ is formed with detection light 2, two-beam constructs the transparent effect of electromagnetically induced in intersection
It answers, then controls light 1 and optical resonator is reflected by the second polarization splitting prism 6 again, avoid it in cavity circulation.
Control light 2 intersects with the detection low-angle in electromagnetically induced transparent medium gas chamber 5 of light 1, is second inclined in order to prevent
Shake Amici prism 6 cannot fully reflective control light 2 when so that a part control light 2 with detect light 1 in sample media gas chamber 6
Eclipse effect as a result, and can be avoided control light 2 in intracavitary resonance in this way.
Optical resonator is confocal cavity.
Two end faces of electromagnetically induced transparent medium gas chamber are covered with anti-reflection film, for reducing intracavitary loss.
Electromagnetically induced transparent medium is the atoms such as rubidium, sodium or caesium.
For reflecting control light 2, detection light 1 is transmitted for first polarization splitting prism 4 and the second polarization splitting prism 6.
The method measured using the above-mentioned continuous wave-cavity ring-down spectroscopy device based on the transparent effect of electromagnetically induced, packet
It includes:
A. the selection of lightwave signal
Its intensity is selected and adjusted to the wavelength and frequency of detection light 1 and control light 2, keeps it transparent in electromagnetically induced
The transparent effect of electromagnetically induced is constructed in medium gas chamber, realizes zero absorption and light speed reduction to detection light；
To detection light 1 and control light 2 wavelength and frequency selected and adjusted its intensity, in particular to: detection 1 He of light
It controls light 2 and its wavelength and frequency is determined according to the level structure of the electromagnetically induced transparent medium of selection, and be locked in building electricity
In the transparent required energy level transition of Magnetic guidance, while detecting light 1 and controlling the intensity of light 2 according to the transparent effect of electromagnetically induced and light
The detection limit of electric explorer does specific adjustment, under the premise of guaranteeing that photodetector can detect detection optical signal,
Detect luminous intensity should much smaller than control luminous intensity, and control luminous intensity can by measurement be swung with declining in the case of Conditions Sample when
Between optimize, choose ring-down time longest when intensity.
B. lightwave signal enters optical resonator and reflects in intracavitary formation
B1) detection light 1 is after the front cavity mirror of optical resonator enters optical resonator, due to polarization relation, first full impregnated
The first polarization splitting prism 4 is crossed, is then worn by electromagnetically induced transparent medium gas chamber 5 using the second polarization splitting prism 6
It crosses after sample gas chamber 7 and reaches the Effect of Back-Cavity Mirror 8 of optical resonator, most of light can reflect back and small in cavity circulation, one at this time
Part light can transmit optical resonator and be received by photodetector 9；
B2) it is intracavitary by the first polarization splitting prism 4 to be reflected into optical resonance for control light 2, and control light 2 is by adjusting it
For polarization so that it is reflected at the first polarization splitting prism 4 and the second polarization splitting prism 6, control light 2 is passing through electromagnetically induced
When transparent medium gas chamber 5, intersecting for an angle, θ is formed with detection light 1, two-beam is transparent in intersection building electromagnetically induced
Then effect controls light 2 and reflects optical resonator by the second polarization splitting prism 6 again, avoids it in cavity circulation；
C. the processing analysis of lightwave signal
C1. signal generator 11 exports triangle wave voltage driving signal and is applied on piezoelectric ceramics 10, scans optical resonance
The length of chamber, the longitudinal mode position of chamber can also scan back and forth therewith at this time, when chamber longitudinal mode position is overlapped with detection light frequency, detection
Light 1 is coupled into optical resonator and forms stable resonance intracavitary；
C2. photodetector 9 receives 1 signal of detection light transmitted from the Effect of Back-Cavity Mirror 8 of optical resonator, measures first not
It is put into transmission spectrum when sample to be tested gas chamber 7, the i.e. transmission spectrum of cavity, sample to be tested is then put into sample to be tested gas chamber 7 and is surveyed
Obtain the transmission spectrum of sample；
D. transmission spectrum is analyzed by computer and obtains the ring-down time of cavity and sample, the concentration of sample is then calculated
Or type.Due to using continuous light laser as light source here, and without using Threshold Detection method, so detection light exists
Resonant cavity can be all injected during entire transmission peaks, needs to be handled transmission peaks to eliminate the shadow of detection light whole process injection
It rings.Specific step is as follows, makes the symmetrical curve in transmission peaks forward position using transmission peaks peak position as symmetry axis first, then with saturating
It penetrates behind peak along the symmetrical curve is subtracted, obtains new curve, then with exponential equation: y=y0+ Aexp (Rx), is fitted new curve
Edge afterwards.According to the definition of ring-down time, i.e. intensity is reduced to the time required when the 1/e of maximum intensity, can be by fitting
Curve obtain the ring-down time of cavity and sample, specific ring-down time can indicate are as follows:
Y=y0+Aexp(Rx)
Wherein, x is the abscissa of new peak of curve；y0, A and R are the constant terms in fit equation.
Specifically, in selection rubidium atom as electromagnetically induced transparent medium, and select to detection rubidium of the light wave with absorption
Atom vapor is as sample to be tested.Chamber transmission spectrum when effect transparent there are electromagnetically induced is as shown in Figure 2 a, and passes through above-mentioned number
According to treatment process, its ring-down time has been obtained by being fitted new curve failing edge.What is indicated in Fig. 2 a is without data processing
When, chamber when effect transparent there are electromagnetically induced transmits spectral line；Vertical dotted line in Fig. 2 b is located at the peak value position of figure a transmission peaks
It sets, in this, as symmetry axis, makes the symmetrical curve of chamber transmission peaks rising edge, as shown in the dotted line in Fig. 2 c；Fig. 2 d is by chamber
After transmission peaks failing edge subtracts the symmetrical curve of rising edge, obtained new curve, and data fitting is carried out, or fitting is bent
Line.
By changing sample to be tested in intracavitary length, corresponding chamber transmission spectrum is measured, so that it is long to obtain different samples
It spends, i.e., the ring-down time in different sample atoms number situations, concrete outcome is as shown in Figure 3.Dot expression is intracavitary, and there are electromagnetism to lure
Ring-down time when transparent effect is led, square indicates ring-down time when intracavitary effect transparent there is no electromagnetically induced.Solid line and
Dotted line respectively indicates its matched curve.
According to theory analysis, ring-down time expression formula when intracavitary effect transparent there are electromagnetically induced can be write as:
Wherein, that L is indicated is cavity length, leAnd lsRespectively indicate electromagnetically induced transparent medium gas chamber and sample to be tested
Length, c be the light beam of light in a vacuum, vgIndicate light group velocity in electromagnetically induced transparent medium, R indicates the reflection of hysteroscope
Rate, αeAnd αsRespectively indicate the absorption coefficient of electromagnetically induced transparent medium and sample to be tested.In experiment, detection light and control light
When intensity determines, α in expression formulaeAnd vgIt does not change over time.
From figure 3, it can be seen that the ring-down time of sample to be tested has obtained effectively in the presence of the transparent effect of electromagnetically induced
Extension, and its sensitivity, i.e., the corresponding tangent slope size of point on curve have also obtained effectively enhancing, by contrast
Reinforcing effect is about 1.5 times.
The basic principles, main features and advantages of the present invention have been shown and described above.The technology of the industry
Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this
The principle of invention, various changes and improvements may be made to the invention without departing from the spirit and scope of the present invention, these changes
Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its
Equivalent defines.
Claims (7)
1. a kind of concentration or type of the continuous wave-cavity ring-down spectroscopy device measurement sample based on the transparent effect of electromagnetically induced
Method comprising following steps:
A. the selection of lightwave signal
Its intensity is selected and adjusted to the wavelength and frequency of detection light and control light, makes it in electromagnetically induced transparent medium gas
The transparent effect of electromagnetically induced is constructed in room, realizes zero absorption and light speed reduction to detection light；
B. lightwave signal enters optical resonator and reflects in intracavitary formation
B1) detection light is after the front cavity mirror of optical resonator enters optical resonator, and due to polarization relation, first full impregnated crosses first
Then polarization splitting prism passes through electromagnetically induced transparent medium gas chamber, using the second polarization splitting prism, pass through sample gas chamber
Reach the Effect of Back-Cavity Mirror of optical resonator afterwards, most of light can reflect back and in cavity circulation at this time, and sub-fraction light can transmit
Optical resonator is received by photodetector out；
B2) it is intracavitary by the first polarization splitting prism to be reflected into optical resonance for control light, and control light is made by its polarization of adjusting
It obtains it to reflect at the first polarization splitting prism and the second polarization splitting prism, control light is passing through electromagnetically induced transparent medium gas
When room, intersecting for an angle, θ is formed with detection light, two-beam constructs the transparent effect of electromagnetically induced in intersection, then controls
Light processed passes through the second polarization splitting prism again and reflects optical resonator, avoids it in cavity circulation；
C. the processing analysis of lightwave signal
C1. signal generator output triangle wave voltage driving signal is applied on piezoelectric ceramics, scans the length of optical resonator,
The longitudinal mode position of chamber can also scan back and forth therewith at this time, when chamber longitudinal mode position with detection light frequency is overlapped when, detect optical coupling into
Optical resonator and the resonance stable in intracavitary formation；
C2. photodetector receives the detection optical signal transmitted from the Effect of Back-Cavity Mirror of optical resonator, measures be not put into sample first
Transmission spectrum when product gas chamber, the i.e. transmission spectrum of cavity, are then put into the transmission spectrum that sample gas chamber measures sample for sample to be tested；
D. by computer analyze transmission spectrum obtain the ring-down time of cavity and sample, be then calculated sample concentration or
Type；
Wherein, the continuous wave-cavity ring-down spectroscopy device of the transparent effect of the electromagnetically induced, comprising: semiconductor laser,
Light source of the semiconductor laser as detection light and control light, is successively arranged in the detection light optical path of its outgoing
The front cavity mirror of optical resonator, the first polarization splitting prism, electromagnetically induced transparent medium gas chamber, the second polarization splitting prism, to
The Effect of Back-Cavity Mirror of sample gas chamber, optical resonator, and the photodetector for receiving detection optical signal；
The front cavity mirror of the optical resonator and the Effect of Back-Cavity Mirror composition of optical resonator decline and swing chamber；
The optical resonator Effect of Back-Cavity Mirror is equipped with piezoelectric ceramics, and the piezoelectric ceramics is connected with signal generator, the signal
Generator provides voltage signal for the piezoelectric ceramics；
The control light is reflected into that optical resonance is intracavitary, and the control light passes through adjusting by first polarization splitting prism
It is polarized so that it is reflected at first polarization splitting prism and second polarization splitting prism, and the control light is passing through
When crossing electromagnetically induced transparent medium gas chamber, intersecting for an angle, θ is formed with the detection light, two-beam is constructed in intersection
The transparent effect of electromagnetically induced, then the control light passes through second polarization splitting prism again and reflects optical resonator, keeps away
Exempt from it in cavity circulation；
The step d, specifically includes: being first symmetrical with transmission peaks peak position to use continuous light laser as light source
Axis makes the symmetrical curve in transmission peaks forward position, then with along subtracting the symmetrical curve, obtaining new curve after transmission peaks, then with referring to
Number equation: y=y0+ Aexp (Rx) is fitted the rear edge of new curve；According to the definition of ring-down time, i.e. intensity is reduced to most high-strength
The required time when 1/e of degree obtains the ring-down time of cavity and sample by the new curve fitted, and ring-down time indicates
Are as follows:
Y=y0+Aexp(Rx)
Wherein, x is the abscissa of new peak of curve；y0, A and R are the constant terms in fit equation.
2. the method as described in claim 1, which is characterized in that wherein the angle, θ is 0 °~2 °.
3. the method as described in claim 1, which is characterized in that wherein the optical resonator is the symmetrical cavity configuration, non-stablized
It is symmetrical to stablize cavity configuration, v-shaped cavity structure or ring cavity structure.
4. method as claimed in claim 3, which is characterized in that wherein the optical resonator is confocal cavity.
5. the method as described in claim 1, which is characterized in that the wherein front cavity mirror and optical resonator of the optical resonator
Back cavity specular reflectivity be all larger than 99.5%.
6. the method as described in claim 1, which is characterized in that wherein two end faces of the electromagnetically induced transparent medium gas chamber
It is covered with anti-reflection film.
7. the method as described in claim 1, which is characterized in that wherein the electromagnetically induced transparent medium is that rubidium, sodium or caesium are former
Son.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610836076.7A CN106290247B (en) | 2016-09-21 | 2016-09-21 | Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610836076.7A CN106290247B (en) | 2016-09-21 | 2016-09-21 | Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106290247A CN106290247A (en) | 2017-01-04 |
| CN106290247B true CN106290247B (en) | 2019-05-24 |
Family
ID=57713091
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610836076.7A Active CN106290247B (en) | 2016-09-21 | 2016-09-21 | Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106290247B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111239062B (en) * | 2020-02-04 | 2021-01-01 | 中国计量科学研究院 | Gas quantitative detection equipment and method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011158384A (en) * | 2010-02-02 | 2011-08-18 | Seiko Epson Corp | Particulate detector |
| CN104819957A (en) * | 2015-02-11 | 2015-08-05 | 中国科学院长春光学精密机械与物理研究所 | CRDS principle-based gas concentration measurement system of continuously adjustable laser light source |
| CN104767119B (en) * | 2015-03-24 | 2017-09-12 | 中国科学院上海光学精密机械研究所 | Regulable center frequency humorous frequency stabilizing device of semiconductor laser and frequency-stabilizing method |
| CN105375250B (en) * | 2015-12-02 | 2018-04-24 | 山西大学 | A kind of atom-chamber coupling produces the method and device of high-order transverse mode |
-
2016
- 2016-09-21 CN CN201610836076.7A patent/CN106290247B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN106290247A (en) | 2017-01-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106990091B (en) | Frequency locking V-shaped enhancement cavity for enhancing gas Raman spectrum detection signal | |
| US8456640B2 (en) | Apparatus and method for measuring reflectance of optical laser components | |
| CN105651703B (en) | A kind of optical cavity ring-down gas measurement of extinction coefficient method changed based on chamber length | |
| CN106556576B (en) | A method of high reflection/highly transmissive optical element reflectivity and transmitance are measured based on optical cavity ring-down technology simultaneously | |
| CN109061783A (en) | Optical resonator reflecting prism and its optical resonator and optical spectrum instrumentation | |
| CN102918456A (en) | Terahertz wave generation element, terahertz wave detection element, and terahertz time domain spectroscope device | |
| CN107037003A (en) | A kind of system that moisture content in high-purity gas is detected based on cavity ring down spectroscopy technology | |
| CN105527263B (en) | With the method and device of the laser induced fluorescence optical path of fiber beam splitting | |
| CN101441117B (en) | Temperature sensor probe | |
| CN103398964A (en) | Gas detection method based on cavity enhancement technique | |
| US20190219505A1 (en) | Device for analysing a specimen using the goos-hänchen surface plasmon resonance effect | |
| CN113916802A (en) | Automatic calibration open-circuit type laser gas detection device and implementation method | |
| CN110411960A (en) | A kind of cavity ring-down spectroscopy instrument system | |
| CN106290247B (en) | Continuous wave-cavity ring-down spectroscopy device and method based on the transparent effect of electromagnetically induced | |
| CN113721173A (en) | Optical fiber SERF atomic magnetometer device based on reflection type bidirectional pumping | |
| CN205176310U (en) | Reflecting prism for optical resonator and optical resonator and spectral measurement appearance thereof | |
| JPH0359439A (en) | Optical fiber sensor | |
| CN205212168U (en) | Speculum for optical resonantor and optical resonantor and spectral measurement appearance thereof | |
| CN107991267A (en) | The tunable diode laser absorption spectroscopy gas-detecting device and method of wavelength agile | |
| CN207636485U (en) | The tunable diode laser absorption spectroscopy gas-detecting device of wavelength agile | |
| CN113777073A (en) | Gas detection method and system based on optical phase amplification | |
| CN207850319U (en) | A kind of angle detection device | |
| CN110501307A (en) | Optical fiber surface plasmon resonance body index sensor based on quantum enhancing | |
| He et al. | Research on high-precision oxygen partial pressure sensor based on TDLAS technology | |
| CN113465719B (en) | Method and device for simultaneously measuring sound velocity and refractive index of fluid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |