CN109100316A - A kind of high reflection mirror screening technique applied to optical cavity structure - Google Patents
A kind of high reflection mirror screening technique applied to optical cavity structure Download PDFInfo
- Publication number
- CN109100316A CN109100316A CN201811025937.9A CN201811025937A CN109100316A CN 109100316 A CN109100316 A CN 109100316A CN 201811025937 A CN201811025937 A CN 201811025937A CN 109100316 A CN109100316 A CN 109100316A
- Authority
- CN
- China
- Prior art keywords
- high reflection
- reflection mirror
- optical
- motion seat
- convex lens
- 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.)
- Pending
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
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
A kind of high reflection mirror screening technique applied to optical cavity structure, this method feature is: 1), according to the photoabsorption cross-section feature of the atmospheric molecule of the concentration undetermined, suitable high reflection mirror is selected, wave-length coverage where making the reflectivity curve high level end of high reflection mirror is Chong Die with wave-length coverage where the maximum light absorption section of the central peak wavelength of source emissioning light spectrum and the atmospheric molecule of concentration undetermined as far as possible；2), meeting above-mentioned steps 1) in the case where, it is assumed that the reflectance peak of high reflection mirror is located at wavelength Xmax, reflectance peak Rmax, in the wavelength XmaxThe light transmittance at place is that T needs to maximize then in final choice high reflection mirrorValue can be only achieved best sensitivity and signal-to-noise ratio.The optical cavity structure of the high reflection mirror filtered out in conjunction with this method can not only effectively, easily detect the concentration of atmospheric molecule, and the atmospheric molecule concentration of super low concentration can be effectively detected.
Description
Technical field
This application involves environmental monitoring technology field more particularly to a kind of high reflection mirror screening sides applied to optical cavity structure
Method.
Background technique
Along with society, economic continuous development, atmosphere pollution is in world's most area, especially in developing country
Area increasingly attracts people's attention.In order to detect the severity of atmosphere pollution, it usually needs using detecting instrument to big
Gas molecule (such as gas molecule NO2、HCHO、CHOCHO、N2O5、NO3, HONO, aerosol etc.) concentration detected.Existing
In technology, using detecting instrument detection atmospheric molecule concentration before, it usually needs first with the calibrating gas of known concentration come
The sensitivity coefficient (sensitivity coefficient) of detecting instrument is demarcated, and is demarcated with the calibrating gas of known concentration
The sensitivity coefficient of detecting instrument can add additional complexity and step to detection；In addition, the purchase of calibrating gas, transport etc. can
Can costly, it is cumbersome, or even be difficult to calibrating gas (such as N obtained sometimes2O5And NO3), to aggravate detection difficulty；In addition,
Existing detecting instrument is undesirable for the detection effect of the atmospheric molecule of super low concentration.
Summary of the invention
A kind of high reflection mirror screening technique applied to optical cavity structure disclosed in the embodiment of the present application is screened in conjunction with this method
The optical cavity structure of high reflection mirror out can not only effectively, easily detect atmospheric molecule (such as NO2、HCHO、CHOCHO、N2O5、
NO3, HONO etc.) concentration, and the atmospheric molecule concentration of super low concentration can be effectively detected.
The embodiment of the present application first aspect discloses a kind of high reflection mirror screening technique applied to optical cavity structure, the optical cavity
Structure includes:
Cavity pipe, the left end of the cavity pipe are equipped with the first high reflection mirror, and it is high anti-that the right end of the cavity pipe is equipped with second
Penetrate mirror；The mirror surface of the mirror surface of first high reflection mirror and second high reflection mirror realizes collimation；First high reflection mirror
Outside be equipped with the first convex lens, the outside of second high reflection mirror is equipped with the second convex lens；The first end of first optical fiber is used
In the emission port of connection light source, the second end of first optical fiber is placed in the outside focus of first convex lens；The
For the first end of two optical fiber for connecting spectrometer, the second end of second optical fiber is placed on the outside of second convex lens
In focus；When being full of the gas of the atmospheric molecule containing concentration undetermined in the cavity pipe, first convex lens is to described
The cavity pipe is injected after the collimation of light derived from first optical fiber, so that light roundtrip between the high reflection mirror of two sides is multiple
After leave the cavity pipe and focused on second optical fiber via second convex lens, then led via second optical fiber
Enter the spectrometer；
Wherein, the high reflection mirror screening technique, comprising the following steps:
1), according to the photoabsorption cross-section feature of the atmospheric molecule of the concentration undetermined, suitable high reflection mirror is selected, height is made
Wave-length coverage where the reflectivity curve high level end of reflecting mirror as far as possible with the central peak wavelength of source emissioning light spectrum and to
Wave-length coverage overlapping where determining the maximum light absorption section of the atmospheric molecule of concentration；
2), meeting above-mentioned steps 1) in the case where, it is assumed that the reflectance peak of high reflection mirror is located at wavelength Xmax, reflection
Rate peak value is Rmax, in the wavelength XmaxThe light transmittance at place is that T needs to maximize then in final choice high reflection mirrorValue can be only achieved best sensitivity and signal-to-noise ratio.
Based on the embodiment of the present application in a first aspect, in the first embodiment of the embodiment of the present application first aspect, institute
State method further include:
First optical motion seat is set, and the left end of the cavity pipe is arranged in the first optical motion seat, and described
First high reflection mirror is fixed on the first optical motion seat；
The first optical motion seat is equipped with tilt angle for adjusting first high reflection mirror, so that described the
The mirror surface of the mirror surface of one high reflection mirror and second high reflection mirror realizes the adjusting screw of collimation.
The first embodiment based on the embodiment of the present application first aspect, the second of the embodiment of the present application first aspect
In kind embodiment, the method also includes:
Second optical motion seat is set, the outside of the first optical motion seat is arranged in the second optical motion seat,
And first convex lens is fixed on the second optical motion seat；
The second optical motion seat is equipped with for adjusting first convex lens relative to first high reflection mirror
Tilt angle so that first convex lens and first high reflection mirror realize the adjusting screw of collimation between the two.
Second of embodiment based on the embodiment of the present application first aspect, in the third of the embodiment of the present application first aspect
In kind embodiment:
The second end of first optical fiber is arranged on the second optical motion seat, and the second optical motion seat
On be additionally provided with for the distance between the second end of the first optical fiber described in Level tune and first convex lens so that described
The second end of one optical fiber is placed on the optical fiber adjusting knob in the outside focus of first convex lens.
Second of the first embodiment or the embodiment of the present application first aspect based on the embodiment of the present application first aspect
The third embodiment of kind of embodiment or the embodiment of the present application first aspect, the of the embodiment of the present application first aspect
In four kinds of embodiments, the method also includes:
Second optical motion seat is set, the outside of the first optical motion seat is arranged in the second optical motion seat,
And first convex lens is fixed on the second optical motion seat；
The second optical motion seat is equipped with for adjusting first convex lens relative to first high reflection mirror
Tilt angle so that first convex lens and first high reflection mirror realize the adjusting screw of collimation between the two.
The 4th kind of embodiment based on the embodiment of the present application first aspect, the 5th of the embodiment of the present application first aspect the
Kind embodiment, the method also includes:
4th optical motion seat is set, the outside of the third optical motion seat is arranged in the 4th optical motion seat,
And second convex lens is fixed on the 4th optical motion seat；
The 4th optical motion seat is equipped with for adjusting second convex lens relative to second high reflection mirror
Tilt angle so that second convex lens and second high reflection mirror realize the adjusting screw of collimation between the two.
The 5th kind of embodiment based on the embodiment of the present application first aspect, the 6th of the embodiment of the present application first aspect the
In kind embodiment:
The second end of second optical fiber is arranged on the 4th optical motion seat, and the 4th optical motion seat
On be additionally provided with for the distance between the second end of the second optical fiber described in Level tune and second convex lens so that described
The second end of two optical fiber is placed on the optical fiber adjusting knob in the outside focus of second convex lens.
The 6th kind of embodiment based on the embodiment of the present application first aspect, the 7th of the embodiment of the present application first aspect the
In kind embodiment, the method also includes:
The first bellows and the first mirror are set gradually from the first optical motion seat to the left end of the cavity pipe
Seat and chamber mount；
First microscope base and chamber mount are equipped with the air inlet pipe for being pumped into gas to the cavity pipe.
The 7th kind of embodiment based on the embodiment of the present application first aspect, the 8th of the embodiment of the present application first aspect the
In kind embodiment, the method also includes:
The second bellows and the second mirror are set gradually from the third optical motion seat to the right end of the cavity pipe
Seat and chamber mount；
Second microscope base and chamber mount are equipped with for the escape pipe for the cavity pipe output gas.
The 8th kind of embodiment based on the embodiment of the present application first aspect, the 9th of the embodiment of the present application first aspect the
In kind embodiment, the method also includes:
Further it is arranged on first microscope base and chamber mount for inputting purge gass to block in the cavity pipe
The first purge gass air inlet pipe for directly being contacted with the mirror surface of first high reflection mirror of gas；
Further it is arranged on second microscope base and chamber mount for inputting purge gass to block in the cavity pipe
The second purge gass air inlet pipe for directly being contacted with the mirror surface of second high reflection mirror of gas；
Wherein, the purge gass include pure nitrogen gas.
As can be seen from the above technical solutions, the embodiment of the present application has the advantage that
In the embodiment of the present application, in the optical cavity structure of the high reflection mirror filtered out in conjunction with the high reflection mirror screening technique
In, when the gas full of the atmospheric molecule containing concentration undetermined in the cavity pipe, first convex lens can be to described
The cavity pipe is injected after the collimation of light derived from first optical fiber, so that light roundtrip between the high reflection mirror of two sides is multiple
After leave the cavity pipe and focused on second optical fiber via second convex lens, then led via second optical fiber
Enter the spectrometer and carries out optical absorption measurement.The embodiment of the present application can be by directly measuring atmospheric molecule (such as NO2、HCHO、
CHOCHO、N2O5、NO3, HONO etc.) light absorption measure the concentration of atmospheric molecule, so do not need the standard with known concentration
Gas demarcates the sensitivity coefficient of detecting instrument, so as to effectively, easily detect atmospheric molecule (such as NO2、HCHO、
CHOCHO、N2O5, HONO etc.) concentration and Atmospheric particulates delustring；In addition, light is high anti-on two sides in the embodiment of the present application
Roundtrip between mirror is penetrated, absorption light path can be dramatically increased, increased multiple is 1/ (1-R), and wherein R is the mirror of high reflection mirror
Face reflectivity, it is assumed that R 0.9999, and the distance between two sides high reflection mirror is 1 meter, then it can be (in 1 meter of the spacing)
The absorption light path for realizing ten thousand metres (i.e. 10 kilometers), according to Beer-Lambert law of light absorption, the absorption light path of this overlength
The absorption of atmospheric molecule can be dramatically increased, so as to which the atmospheric molecule concentration of super low concentration is effectively detected.
Detailed description of the invention
It in order to more clearly explain the technical solutions in the embodiments of the present application, below will be to needed in the embodiment
Attached drawing is briefly described, it should be apparent that, the drawings in the following description are only some examples of the present application, for ability
For the those of ordinary skill of domain, without creative efforts, it can also be obtained according to these attached drawings other attached
Figure.
Fig. 1 is a kind of schematic diagram of atmospheric molecule detection system disclosed in the embodiment of the present application；
Fig. 2 is a kind of structural schematic diagram of optical cavity structure disclosed in the embodiment of the present application；
Fig. 3 be a kind of high reflection mirror reflectance curve disclosed in the embodiment of the present application, LED light source luminosity curve and certain wait for
Determine the contrast schematic diagram between the light absorption border curve three of the atmospheric molecule of concentration；
Fig. 4 is a kind of process signal of the high reflection mirror screening technique applied to optical cavity structure disclosed in the embodiment of the present application
Figure；
Fig. 5 is a kind of flow diagram of atmospheric molecule detection method disclosed in the embodiment of the present application.
Specific embodiment
Below in conjunction with the attached drawing in the embodiment of the present application, technical solutions in the embodiments of the present application carries out clear, complete
Site preparation description, it is clear that the described embodiments are only a part but not all of the embodiments of the present application.Based on this
Embodiment in application, every other reality obtained by those of ordinary skill in the art without making creative efforts
Example is applied, shall fall in the protection scope of this application.
It should be noted that the term " includes " of the embodiment of the present application and " having " and their any deformation, it is intended that
Be to cover it is non-exclusive include, for example, containing the process, method, system, product or equipment of a series of steps or units not
Those of be necessarily limited to be clearly listed step or unit, but may include be not clearly listed or for these processes, side
The intrinsic other step or units of method, product or equipment.
A kind of high reflection mirror screening technique applied to optical cavity structure disclosed in the embodiment of the present application is screened in conjunction with this method
The optical cavity structure of high reflection mirror out can not only effectively, easily detect atmospheric molecule (such as NO2、HCHO、CHOCHO、N2O5、
NO3, HONO etc.) concentration, and the atmospheric molecule concentration of super low concentration can be effectively detected.Be combined below attached drawing into
Row detailed description.
For a kind of better, the clearer high reflection mirror applied to optical cavity structure for understanding the embodiment of the present application description
Screening technique, below first to the invention relates to atmospheric molecule detection system be described.
Referring to Fig. 1, Fig. 1 is a kind of schematic diagram of atmospheric molecule detection system disclosed in the embodiment of the present application.In Fig. 1 institute
In the atmospheric molecule detection system shown, by identical two sides high reflection mirror (i.e. positioned at the high reflection mirror of left end and positioned at right end
High reflection mirror) composition optical cavity, the mirror surface of the two sides high reflection mirror, which is realized, to be collimated, i.e., the mirror surface of the described two sides high reflection mirror is mutual
Face；The optical cavity is equipped with air inlet (be equipped with air inlet pipe) and gas outlet (i.e. equipped with escape pipe), can be with by air inlet
Gas (such as NO full of the atmospheric molecule containing concentration undetermined in the optical cavity2、HCHO、CHOCHO、N2O5、NO3、HONO
Deng)；One end of the optical cavity is laid with the first convex lens, and the other end of the optical cavity is laid with the second convex lens.Wherein, first
The light emitting mouth of one end connection light source of optical fiber, the light source can be strong to incoherence by thermostat (such as thermoelectric (al) cooler)
Light source (such as light emitting diode) carries out the constant temperature light source of constant temperature composition, and the other end of first optical fiber is placed on institute in Fig. 1
In the focus of the first convex lens shown；Wherein, one end of the second optical fiber connects spectrometer (such as wide-band spectrum instrument), and described second
The other end of optical fiber is placed in the focus of the second convex lens shown in Fig. 1.The spectrometer (such as wide-band spectrum instrument)
It can be connect by data line with control computer.
Optionally, in atmospheric molecule detection system shown in Fig. 1, when the light source is by thermostat (such as thermoelectric-cooled
Device) to incoherence intense light source (such as light emitting diode) carry out constant temperature composition constant temperature light source when, constitute the constant temperature light source
The thermostat (such as thermoelectric (al) cooler) and the incoherence intense light source (such as light emitting diode) can be by light source and thermostats
Drive module controls its work, realizes constant temperature effect.Optionally, in atmospheric molecule detection system shown in Fig. 1, Ke Yiyou
Power supply is respectively the light source and thermostat drive module, the constant temperature light source, the spectrometer and control by supply lines
Computer (such as computer) power supply.Optionally, in atmospheric molecule detection system shown in Fig. 1, can also include air-extractor and
Solenoid valve；Correspondingly, power supply can also be respectively the air-extractor and solenoid valve power supply by supply lines.The pumping
The function of equipment is atmospheric molecule (such as NO that will contain concentration undetermined according to the flow velocity set2、HCHO、CHOCHO、N2O5、
NO3, HONO etc.) gas be pumped into the optical cavity by the air inlet of the optical cavity, until containing in the optical cavity full of described
There is the gas of the atmospheric molecule of concentration undetermined.For example, the air-extractor can be a metering aspiration pump, or use
The combination of pump plus mass flowmenter, or be the combination for pumping supernumerary segment flow tube, the embodiment of the present application is not construed as limiting.Wherein, described
Solenoid valve can be connect by data line with the control computer；The function of the solenoid valve is, when input matching voltage signal
When, switch state can change；For example, after inputting matching voltage signal, which can for normally opened solenoid valve
To close；And the solenoid valve for often closing, inputting matched voltage signal can be such that the solenoid valve opens.Shown in Fig. 1 is big
Switch of the purpose primarily as control adscititious gases gas circuit of solenoid valve is added in gas molecular detection system, in order to incite somebody to action
Different adscititious gases, which are added in gas circuit, to be chemically reacted, with realize be filled in the optical cavity it is different containing undetermined dense
The gas of the atmospheric molecule of degree, to realize the Concentration Testing function of the atmospheric molecule of different concentration undetermined.
It is to be appreciated that for ease of description, only illustrating one in atmospheric molecule detection system shown in Fig. 1
The optical cavity, in practical applications, the quantity of the optical cavity can be not construed as limiting for one or more, the embodiment of the present application.
In atmospheric molecule detection system shown in Fig. 1, by thermoelectric (al) cooler to incoherence intense light source (such as light-emitting diodes
Pipe) carry out constant temperature constitute constant temperature light source when, can to avoid due to temperature drift cause source emissioning light spectrum change.Due to the perseverance
The light that warm light source is launched can be exported via first optical fiber, and the other end of first optical fiber is placed on again
In the focus of first convex lens shown in Fig. 1, it can be close in parallel from the light that first convex lens appears in this way
Light (light that the i.e. described constant temperature light source is launched is collimated by first convex lens), and from described in the injection of the high reflection mirror in left side
Optical cavity, and be successfully entered the light of the optical cavity roundtrip between the high reflection mirror of two sides and repeatedly dramatically increase absorption light path
Afterwards, the optical cavity finally is left from the high reflection mirror on right side, and is focused on second optical fiber via second convex lens,
It finally imports the spectrometer and carries out light splitting and photon detection, to obtain in the optical cavity of one wavelength range of covering full of institute
The light intensity map I (λ) when the gas of the atmospheric molecule containing concentration undetermined is stated, and is supplied to the control computer, by the control
Computer processed calculates the concentration c of the atmospheric molecule of the concentration undetermined according to the light intensity map I (λ) and preset formula.
In the embodiment of the present application, light roundtrip between the high reflection mirror of two sides can dramatically increase absorption light path, inhale
The receipts increased multiple of light path is 1/ (1-R), and wherein R is the specular reflectivity of high reflection mirror, it is assumed that R is 0.9999 and two sides is high anti-
Penetrating the distance between mirror is 1 meter, then the absorption light path of ten thousand metres (i.e. 10 kilometers), root can be realized (in 1 meter of the spacing)
According to Beer-Lambert law of light absorption, the absorption light path of this overlength can dramatically increase the absorption of atmospheric molecule, so as to
The atmospheric molecule concentration of super low concentration is effectively detected.
In the embodiment of the present application, different atmospheric molecules is also different to the characteristic absorption of ultraviolet-visible light.Such as it is big
Gas molecule NO2There is strong characteristic absorption within the scope of 350-600nm, it is therefore, big containing concentration undetermined when being full of in above-mentioned optical cavity
Gas molecule NO2Gas when, the luminous intensity in this wavelength band has obvious decaying, and the ratio to decay at different wave length is not
Together, occurrence depends on NO2Absorption at these wavelength is strong and weak.Therefore, in the embodiment of the present application, control computer can be right
Light intensity map I (λ) carries out spectral data analysis, to analyze the atmospheric molecule NO of concentration undetermined2And its concentration.
In the embodiment of the present application, in atmospheric molecule detection system shown in Fig. 1, the atmospheric molecule containing concentration undetermined
Gas can be pumped into the optical cavity by air-extractor (a such as metering aspiration pump).If the atmosphere containing concentration undetermined
Ambient particle object in the gas of molecule is dense, and the delustring as caused by ambient particle object is very strong, can be added in air inlet
One particulate filter (such as Particulate filter) is filtered ambient particle object.In other words, particulate filter (as
Grain object filter membrane) it may be used to the gas of the atmospheric molecule containing concentration undetermined after particulate filter filtering
Into in the optical cavity.
In the embodiment of the present application, in atmospheric molecule detection system shown in Fig. 1, the hardware for needing to process has:
(1) optical cavity structure:
Referring to Fig. 2, Fig. 2 is a kind of structural schematic diagram of optical cavity structure disclosed in the embodiment of the present application.As shown in Fig. 2,
The optical cavity structure includes:
The left end of cavity pipe 11, the cavity pipe 11 is equipped with the first high reflection mirror 21, and the right end of the cavity pipe 11 is equipped with
Second high reflection mirror 22；Wherein, the cavity pipe 11, first high reflection mirror 21 and second high reflection mirror 22 can be with
Constitute the optical cavity described above；
Wherein, the mirror surface of the mirror surface of first high reflection mirror 21 and second high reflection mirror 22 realizes collimation；It is described
The outside of first high reflection mirror 21 is equipped with the first convex lens 31, and the outside of second high reflection mirror 22 is equipped with the second convex lens
32；
The first end of first optical fiber 41 is used to connect the emission port of light source, and the second end of first optical fiber 41 is (i.e. described
The terminal of first optical fiber) it is placed in the outside focus of first convex lens 31；The first end of second optical fiber 42 is for connecting
Spectrometer is connect, the second end (terminal of i.e. described second optical fiber) of second optical fiber 42 is placed on second convex lens
In the focus of outside；
When being full of the gas of the atmospheric molecule containing concentration undetermined in the cavity pipe 11, first convex lens 31 is right
The cavity pipe is injected and (injected from first high reflection mirror 21 of left end) after the collimation of light derived from first optical fiber 41
11, so that light leaves the cavity pipe 11 after roundtrip is multiple between two sides high reflection mirror (i.e. 21 and 22) and via institute
It states the second convex lens 32 to focus on second optical fiber 42, then imports the spectrometer via second optical fiber 42.
Wherein, the spectrometer can carry out light splitting and photon detection, to obtain the luminous intensity of one wavelength range of covering
Figure I (λ) is simultaneously supplied to control computer, to calculate the concentration c of the atmospheric molecule of the concentration undetermined.
As an alternative embodiment, in the embodiment of the present application, the optical cavity structure can also include:
The left end of the cavity pipe 11, and institute is arranged in first optical motion seat 51, the first optical motion seat 51
The first high reflection mirror 21 is stated to be fixed on the first optical motion seat 51；
The first optical motion seat 51 is equipped with the tilt angle for adjusting first high reflection mirror 21, so that institute
The mirror surface of the mirror surface and second high reflection mirror 22 of stating the first high reflection mirror 21 realizes the adjusting screw 61 of collimation.
As an alternative embodiment, in the embodiment of the present application, the optical cavity structure can also include:
The outer of the first optical motion seat 51 is arranged in second optical motion seat 52, the second optical motion seat 52
Side, and first convex lens 31 is fixed on the second optical motion seat 52；
The second optical motion seat 52 is equipped with high anti-relative to described first for adjusting first convex lens 31
The tilt angle of mirror 21 is penetrated, so that first convex lens 31 and first high reflection mirror 21 realize the tune of collimation between the two
Save screw 61.
As an alternative embodiment, in the embodiment of the present application:
The second end of first optical fiber 41 is arranged on the second optical motion seat 52, and second optics is transported
It is additionally provided on dynamic seat 52 for the distance between the second end of the first optical fiber 41 and first convex lens 31 described in Level tune,
So that the second end of first optical fiber 41 is placed on the optical fiber adjusting knob in the outside focus of first convex lens 31
62。
As an alternative embodiment, in the embodiment of the present application, the optical cavity structure can also include:
The right end of the cavity pipe 11, and institute is arranged in third optical motion seat 53, the third optical motion seat 53
The second high reflection mirror 22 is stated to be fixed on the third optical motion seat 53；
The third optical motion seat 53 is equipped with the tilt angle for adjusting second high reflection mirror 22, so that institute
The mirror surface of the mirror surface and first high reflection mirror 21 of stating the second high reflection mirror 22 realizes the adjusting screw 61 of collimation.
As an alternative embodiment, in the embodiment of the present application, the optical cavity structure can also include:
The outer of the third optical motion seat 53 is arranged in 4th optical motion seat 54, the 4th optical motion seat 54
Side, and second convex lens 32 is fixed on the 4th optical motion seat 54；
The 4th optical motion seat 54 is equipped with high anti-relative to described second for adjusting second convex lens 32
The tilt angle of mirror 22 is penetrated, so that second convex lens 32 and second high reflection mirror 22 realize the tune of collimation between the two
Save screw 61.
As an alternative embodiment, the second end of second optical fiber 42 is arranged in institute in the embodiment of the present application
It states on the 4th optical motion seat 54, and is additionally provided on the 4th optical motion seat 54 for the second optical fiber described in Level tune
The distance between 42 second end and second convex lens 32 so that the second end of second optical fiber 42 be placed on it is described
Optical fiber adjusting knob 62 in the outside focus of second convex lens 32.
As an alternative embodiment, in the embodiment of the present application:
From the first optical motion seat 51 to being disposed with the first bellows 71 left end of the cavity pipe 11
With the first microscope base and chamber mount 81；
81 are equipped with the air inlet pipe 811 for being pumped into gas to the cavity pipe 11 on first microscope base and chamber mount.
As an alternative embodiment, in the embodiment of the present application:
The second bellows 72 is disposed with from the third optical motion seat 53 to the right end of the cavity pipe 11
With the second microscope base and chamber mount 82；
Second microscope base and chamber mount 82 are equipped with for the escape pipe 821 for 11 output gas of cavity pipe.
As an alternative embodiment, in the embodiment of the present application:
It is additionally provided on first microscope base and chamber mount 81 for inputting purge gass to block in the cavity pipe 11
The first purge gass air inlet pipe 812 that gas is directly contacted with the mirror surface of first high reflection mirror 21；
It is additionally provided on second microscope base and chamber mount 82 for inputting purge gass to block in the cavity pipe 11
The second purge gass air inlet pipe 822 that gas is directly contacted with the mirror surface of second high reflection mirror 22；
Wherein, the purge gass include pure nitrogen gas, and flow velocity is by the diameter that adds in cleaning gas circuit between 50-70 microns
Miniflow hole (critical orifice) control at 0.05-0.1 liters/min or so.
Based on the atmospheric molecule detection system shown in FIG. 1 and the optical cavity structure shown in Fig. 2, the application is implemented
Example further discloses a kind of high reflection mirror screening technique applied to optical cavity structure.Referring to Fig. 3, Fig. 3 is the embodiment of the present application
A kind of flow diagram of disclosed high reflection mirror screening technique applied to optical cavity structure.As shown in figure 3, the high reflection mirror sieves
Choosing method may comprise steps of:
1), according to the photoabsorption cross-section feature of the atmospheric molecule of the concentration undetermined, suitable high reflection mirror is selected, height is made
Wave-length coverage where the reflectivity curve high level end of reflecting mirror as far as possible with the central peak wavelength of source emissioning light spectrum and to
Wave-length coverage overlapping where determining the maximum light absorption section of the atmospheric molecule of concentration.
It is assumed that the maximum light absorption section of the atmospheric molecule of a certain concentration undetermined is located at wavelength 368nm,
To plurality of LED light sources, after comparison, it was found that, certain type LED light source luminous intensity maximum value is located at wavelength 365nm, and certain type high reflection
The maximum reflectivity of mirror is located within the scope of wavelength 362-374nm, at this time wave where the reflectivity curve high level end of the type high reflection mirror
Maximum light of the long range as far as possible with the central peak wavelength of the type LED light source emission spectrum and the atmospheric molecule of concentration undetermined
Wave-length coverage overlapping, can select type LED and the type high reflection mirror where absorption cross-section.
2), meeting above-mentioned steps 1) in the case where, it is assumed that the reflectance peak of high reflection mirror is located at wavelength Xmax, reflection
Rate peak value is Rmax, in the wavelength XmaxThe light transmittance at place is that T needs to maximize then in final choice high reflection mirrorValue can be only achieved best sensitivity and signal-to-noise ratio.
By taking Fig. 4 as an example, the reflectance peak of the type high reflection mirror is located at wavelength Xmax, wavelength XmaxAbout 365nm, reflectivity
Peak value RmaxAbout 0.9995, and producer's explanation is consulted, the type high reflection mirror is in wavelength XmaxThe light transmittance T at place is about 0.0004,
Then it is calculatedValue about 25.
Assuming that on the market there are also second item high reflection mirror, the reflectance peak of second item high reflection mirror also is located at above-mentioned wavelength
λmax, the reflectance peak R of second item high reflection mirrormaxAbout 0.9998, it is higher than the type high reflection mirror above-mentioned.When not considering height
When anti-lens transmission, higher reflectivity illustrates that light once enters the optical cavity, can be back and forth between the high reflection mirror of two sides
More numbers are reflected, corresponding longest effectively absorbs light path (by d/ (1-Rmax)) provide, wherein d is between the high reflection mirror of two sides
Distance) be it is longer, obtained molecule light absorption signal is bigger, and the sensitivity of equipment is also just higher.But it is sent out by theory deduction
It is existing, when the final noise of equipment is determined by shot noise (shot noise), if the light transmittance T value of high reflection mirror is too low,
It will lead to the photon from light source and the approach such as largely absorb or scatter by eyeglass and lose and cannot be introduced into optical cavity, and final shadow
Ring the sensitivity of equipment.By taking second item high reflection mirror as an example, in wavelength XmaxThe light transmittance T at place is about 0.00004, is calculated
To itValue is 10, and value (25) more corresponding than the type high reflection mirror above-mentioned is small, although it is higher to show that it has
Reflectivity (and therefore having longer effective absorption light path), it is contemplated that the cavity being made from it can not have better sensitivity
Or signal-to-noise ratio.
(2) light source: the light source can be incoherence intense light source, and incoherence intense light source can be using Gao Gong
The single chip LED of rate (5-15W)；Wherein, the number of the light source can be configured according to actual needs, this Shen
Please embodiment be not construed as limiting.
In the embodiment of the present application, one or more incoherence intense light sources (such as LED) are welded in printable circuit board (PCB)
On, then the PCB is fixed on thermoelectric (al) cooler (thermoelectric cooler), so as to by incoherence intense light source (such as
LED) constant temperature is near such as 15 degrees Celsius, to realize the high stability of source emissioning light spectrum.Wherein, to the constant of temperature
It can be realized by one feed circuit of design, feedback signal can be by a PT104 heat being attached on the thermoelectric (al) cooler
Silk (thermistor) is hindered to provide.
It, can since the temperature stability of incoherence intense light source (such as LED) requires very high (positive and negative 0.01 degree Celsius)
Between between incoherence intense light source (such as LED) and the PCB and the PCB and the thermoelectric (al) cooler (TE cooler)
Gap coats high performance hot glue (thermal glue), to guarantee that efficient heat transfer may be implemented between them.Preferably, should
The back side of PCB can be covered with wire, to facilitate the PCB quickly towards radiating on the thermoelectric (al) cooler.In short, any can add
The method of heat transmitting between strong incoherence intense light source (such as the LED) → PCB → thermoelectric (al) cooler (TE cooler) is all
It single can use or combination uses, the embodiment of the present application is not construed as limiting.
(3) gas circuit: in the embodiment of the present application, when the gas for the atmospheric molecule for needing to contain concentration undetermined toward optical cavity filling
When body, a metering aspiration pump can use, perhaps add the combination of mass flowmenter using pump or utilize pump supernumerary segment flow tube
The gas of atmospheric molecule containing concentration undetermined is pumped into institute by the air inlet of the optical cavity according to the flow velocity set by combination
It states in optical cavity, until the gas full of the atmospheric molecule containing concentration undetermined in the optical cavity.When the past optical cavity of needs
When filling zero gas, zero gas is usually from pure nitrogen gas or the steel cylinder of clean air, and zero gas after pressure reducing valve depressurizes, still can by air pressure
A little higher than atmospheric pressure, therefore or the opposite direction (i.e. from gas outlet) of air inlet gas circuit from the optical cavity inject the optical cavity, and from
Air inlet outflow；A triple valve is added in air inlet, gas circuit is switched to the gas circuit of zero gas from the gas circuit of atmospheric sample.
In the embodiment of the present application, atmospheric molecule detection system shown in FIG. 1 can also be there are three additionally may be used in terms of gas circuit
Option:
(A) if, gas need to heat, can additionally plus one section of heating tube, the material of heating tube can be quartz glass
(it is heated to 400-600 degrees Celsius if necessary, such as to NOyThe Concentration Testing of (i.e. nitrogenous object) needs first to be pyrolyzed for NOx)
Or polyfluortetraethylene pipe (is heated to 100 degrees centigrades if necessary, and heats the aerochemistry activity height generated, Yi Biao
Face loss, such as to N2O5Concentration Testing, need first to be pyrolyzed for NO3).The Concentration Testing of the latter is also required to guarantee figure 1 above
In the temperature of the gassiness optical cavity and microscope base bracket it is also constant near 100 degrees Celsius, usually by optical cavity pipeline
Upper winding heating sheet or heater strip paste heating sheet realization on microscope base bracket simultaneously.Similar to the constant temperature to light source, above-mentioned optical cavity
Etc. the holdings of temperature be also required to use a temperature feedback loop.
(B) if, gas need chemical conversion appropriate, such as to nitric oxide NO and ozone O3Detection be respectively necessary for adding
Add O3And NO, in order to convert the two in the optical cavity NO of significant light absorption2.It can be in the air inlet of the optical cavity
Mouthful plus a gas tee tube, the branch of gas tee tube free time connect ambient atmosphere, the gas tee tube free time another
Branch connects ozone generator or nitric oxide steel cylinder, big so that both adscititious gases are added to the external world in the optical cavity
It is chemically reacted in gas, generates the NO for having significant light absorption2.Another branch generally also adds a solenoid valve, realizes
Adscititious gases (such as O3And NO) opening and closing function.That is, different adscititious gases can be added to institute using solenoid valve
It states optical cavity to be chemically reacted, to realize the gas full of the atmospheric molecule containing concentration undetermined in the optical cavity.
(3) if aerosol concentration is excessively high, the surface of high reflecting mirror surface may be attached to and then reduce its reflectivity, at this moment
The property of can choose adds a cleaning gas circuit, to completely cut off contact of the ambient atmosphere with mirror surface.Wherein, the purge gass one of gas circuit are cleaned
As be higher degree nitrogen, miniflow hole (critical of the flow velocity by the diameter that is added in gas circuit between 50-70 microns
Orifice) control is at 0.05-0.1 liters/min or so.
(4) spectrometer and control computer: spectrometer is generally shaped commercial product, may be implemented to be divided, records different waves
The functions such as the light intensity of long position.Controlling computer can be computer, control program and spectral data analysis program generally by opening
Hair quotient oneself writes.
In the embodiment of the present application, the technical principle of atmospheric molecule detection system shown in FIG. 1 are as follows:
Gas full of the atmospheric molecule containing concentration undetermined in the optical cavity being made of two sides high reflection mirror；By light source
(such as constant temperature light source of the thermostat and incoherence intense light source composition) light launched through the first optical fiber by exporting to first convex
In the focus of lens, so that the first convex lens injects optical cavity after collimating to light, the light meeting two sides for being successfully entered optical cavity is high anti-
It penetrates after roundtrip between mirror repeatedly dramatically increases absorption light path and leaves optical cavity, and focus on the second optical fiber via the second convex lens
On, then import spectrometer via the second optical fiber and carry out light splitting and photon detection, to obtain the luminous intensity of one wavelength range of covering
Scheme I (λ), λ indicates the wavelength of light；Light intensity map I (λ) is transferred to control computer, is controlled computer combination light intensity map I (λ)
The concentration c of the atmospheric molecule of concentration undetermined is calculated with preset formula.
In the embodiment of the present application, control computer can be calculated in conjunction with the light intensity map I (λ) and following preset formula
The concentration c of the atmospheric molecule of the concentration undetermined, it may be assumed that
Wherein, the λ indicates the wavelength of the light；The c is the concentration of the atmospheric molecule of the concentration undetermined；It is described
σ (λ) is the absorption cross-section of the atmospheric molecule of the concentration undetermined, and the σ (λ) is known；The R (λ) is the high reflection mirror
To the reflectivity of the light, and the R (λ) is known；The d is in the optical cavity full of the atmosphere for containing concentration undetermined
The length of the part volume of the gas of molecule, and known to the d；The I0(λ) is in the optical cavity first full of without described
The light intensity map that the spectrometer measures when zero gas of the atmospheric molecule of concentration undetermined.
As an example it is assumed that first full of without atmospheric molecule NO in the optical cavity2Zero gas when, what the spectrometer measured
Light intensity map is I0(λ)；The atmospheric molecule NO containing concentration undetermined will be full of in the optical cavity again2Gas, the spectrometer surveys
The light intensity map obtained is I (λ), then control computer can be calculated according to the light intensity map I (λ) and following preset formula
The atmospheric molecule NO of concentration undetermined2ConcentrationThat is:
Wherein, the λ indicates the wavelength of the light；It is describedFor the atmospheric molecule NO of the concentration undetermined2It is dense
Degree；It is describedFor the atmospheric molecule NO of the concentration undetermined2Absorption cross-section, and it is describedIt is known；The R (λ)
It is the high reflection mirror to the reflectivity of the light, and the R (λ) is known；The d is to contain in the optical cavity full of described
The atmospheric molecule NO of concentration undetermined2Gas part volume length, and known to the d；In formula, I (λ),And R
(λ) indicates that luminous intensity I, absorption cross-section σ and specular reflectivity R etc. are the function of wavelength X, changes (before i.e. with wavelength difference
Described in text, NO2It is different to the absorption intensity of the light of different wave length).
In the embodiment of the present application, atmospheric molecule detection system shown in FIG. 1 is by directly measuring atmospheric molecule (such as NO2、
HCHO、CHOCHO、N2O5、NO3, HONO etc.) light absorption measure the concentration of atmospheric molecule, so not needing to use known concentration
Calibrating gas demarcate the sensitivity coefficient of detecting instrument, so as to effectively, easily detect the concentration of atmospheric molecule and big
The delustring of aerated particle object；In addition, light is anti-back and forth between the high reflection mirror of two sides in atmospheric molecule detection system shown in FIG. 1
It penetrates, absorption light path can be dramatically increased, it is ultralow so as to be effectively detected so as to dramatically increase the absorption of atmospheric molecule
The atmospheric molecule concentration of concentration.
Based on atmospheric molecule detection system shown in FIG. 1, the embodiment of the present application further discloses a kind of atmospheric molecule detection
Method.Referring to Fig. 5, Fig. 5 is a kind of flow diagram of atmospheric molecule detection method disclosed in the embodiment of the present application.Such as Fig. 5
Shown, which may comprise steps of:
501, the optical cavity being made of two sides high reflection mirror is provided, and full of big containing concentration undetermined in the optical cavity
The gas of gas molecule；One end of the optical cavity is laid with the first convex lens, and the other end of the optical cavity is laid with the second convex lens.
Wherein, the mirror surface of the two sides high reflection mirror is facing each other.
502, by light that light source is launched by exporting through the first optical fiber to the focus of first convex lens, so that institute
It states after the first convex lens collimates light and injects the optical cavity；Wherein, the light for being successfully entered the optical cavity is high on the two sides
The optical cavity is left after roundtrip is multiple between reflecting mirror, and is focused on the second optical fiber via second convex lens, then
Spectrometer is imported via second optical fiber and carries out light splitting and photon detection, to obtain the light intensity map of one wavelength range of covering
I(λ)；The λ indicates the wavelength of the light.
In the embodiment of the present application, light roundtrip between the high reflection mirror of two sides can dramatically increase absorption light path, inhale
The receipts increased multiple of light path is 1/ (1-R), and wherein R is the specular reflectivity of high reflection mirror, it is assumed that R is 0.9999 and two sides is high anti-
Penetrating the distance between mirror is 1 meter, then the absorption light path of ten thousand metres (i.e. 10 kilometers), root can be realized (in 1 meter of the spacing)
According to Beer-Lambert law of light absorption, the absorption that the absorption light path of this overlength can dramatically increase atmospheric molecule (disappears
Light), so as to which the atmospheric molecule concentration of super low concentration is effectively detected.
503, the light intensity map I (λ) is transferred to control computer, so that the control computer is in conjunction with the light intensity map
I (λ) and preset formula calculate the concentration c of the atmospheric molecule of the concentration undetermined.
In the embodiment of the present application, control computer calculates described undetermined dense in conjunction with the light intensity map I (λ) and preset formula
The concentration c of the atmospheric molecule of degree, comprising:
The control computer calculates the concentration undetermined in conjunction with the light intensity map I (λ) and following preset formula
The concentration c of atmospheric molecule, it may be assumed that
Wherein, the λ indicates the wavelength of the light；The c is the concentration of the atmospheric molecule of the concentration undetermined；It is described
σ (λ) is the absorption cross-section of the atmospheric molecule of the concentration undetermined, and the σ (λ) is known；The R (λ) is the high reflection mirror
To the reflectivity of the light, and the R (λ) is known；The d is in the optical cavity full of the atmosphere for containing concentration undetermined
The length of the part volume of the gas of molecule, and known to the d；The I0(λ) is in the optical cavity first full of without described
The light intensity map that the spectrometer measures when zero gas of the atmospheric molecule of concentration undetermined.
As an alternative embodiment, the gas full of the atmospheric molecule containing concentration undetermined in the optical cavity
Body, comprising:
Using a metering aspiration pump, the gas of the atmospheric molecule containing concentration undetermined is passed through according to the flow velocity set
The air inlet of the optical cavity is pumped into the optical cavity, until full of the atmospheric molecule containing concentration undetermined in the optical cavity
Gas；
Alternatively, the atmosphere containing concentration undetermined is divided according to the flow velocity set using the combination of pump plus mass flowmenter
The gas of son is pumped into the optical cavity by the air inlet of the optical cavity, until containing concentration undetermined full of described in the optical cavity
Atmospheric molecule gas；
Alternatively, the atmospheric molecule of concentration undetermined will be contained according to the flow velocity set using the combination of pump supernumerary segment flow tube
Gas is pumped into the optical cavity by the air inlet of the optical cavity, until full of described big containing concentration undetermined in the optical cavity
The gas of gas molecule.
As an alternative embodiment, in the atmospheric molecule detection method described in Fig. 5, if described containing needing
The ambient particle object determined in the gas of the atmospheric molecule of concentration is dense, then adds a particle in the air inlet of the optical cavity
Object filter, so that the gas of the atmospheric molecule containing concentration undetermined passes through the particulate matter mistake of air inlet addition
Enter in the optical cavity after filter filtering.
As another optional embodiment, described in the light in the atmospheric molecule detection method described in Fig. 5
The intracavitary gas full of the atmospheric molecule containing concentration undetermined, comprising:
Different adscititious gases are added to the optical cavity using solenoid valve to chemically react, to realize in the optical cavity
The interior gas full of the atmospheric molecule containing concentration undetermined.
As an alternative embodiment, the light source includes non-in the atmospheric molecule detection method described in Fig. 5
Coherence's intense light source, wherein incoherence intense light source may include light emitting diode (LED), correspondingly, described in Fig. 5
In atmospheric molecule detection method, constant temperature can also be carried out to the light source using thermostat, to realize constant temperature light source；Wherein, institute
Stating thermostat includes thermoelectric (al) cooler.
It is described to utilize thermostat to the light in the atmospheric molecule detection method described in Fig. 5 in the embodiment of the present application
Source carries out constant temperature, to realize constant temperature light source, comprising:
The incoherence intense light source is welded on printable circuit board (PCB), then the printable circuit board is fixed
On the thermoelectric (al) cooler, and in incoherence intense light source and the printable circuit board and the printable circuit board
High performance hot glue is coated in gap between the thermoelectric (al) cooler, to take the photograph coherence's intense light source constant temperature specified
Near family name's degree, to realize constant temperature light source；The incoherence intense light source includes one or more light emitting diodes.
In the atmospheric molecule detection method described in Fig. 5, by directly measuring atmospheric molecule (such as gas NO2、HCHO、
CHOCHO、N2O5、NO3, HONO etc.) light absorption measure the concentration of atmospheric molecule, so do not need the standard with known concentration
Gas demarcates the sensitivity coefficient of detecting instrument, so as to effectively, easily detecting the concentration and atmosphere of above-mentioned atmospheric molecule
The delustring of particulate matter；In addition, in the atmospheric molecule detection method described in Fig. 3, light between the high reflection mirror of two sides back and forth
Reflection, can dramatically increase absorption light path, super so as to be effectively detected so as to dramatically increase the absorption of atmospheric molecule
The atmospheric molecule concentration of low concentration.
For example, in the embodiment of the present application, described first, second, third and the 4th optical motion seat may include
But it is not limited to the KC1-T optical adjusting frame of Thorlabs company.
The embodiment of the present application may be implemented it is all in 340-900nm wave-length coverage have feature structure absorb
The Concentration Testing of the atmospheric molecule of (structured absorption), comprising:
(a) formaldehyde (HCHO), 1/1000000000th to 10,000,000,000 or so, testing result can be used to detect indoor detection limit
Concentration of formaldehyde, and due to the reliability and accuracy of its result, it can be used as " goldstandard " of indoor formaldehyde detection, for calibrating,
Verify relatively inexpensive, portable formaldehyde sensor and detection device；
(b) glyoxal (CHOCHO), minimum detection limit is generally 1/100000000000th or so.Since glyoxal is atmosphere benzene
And substituted benzene (mainly from motor vehicle exhaust emission, industrial discharge and plant discharging) and isoprene are (mainly from plant
Object discharge and vehicle exhaust etc.) important intermediate that is generated during atmospheric oxidn, liquid phase reactor, which is recognized as, may be
One of source of secondary particulate, so the detection of glyoxal is extremely important to Atmospheric Chemistry research.In addition, formaldehyde and glyoxal
Photodissociation can generate HO2Free radical, the free radical and NO's further reacts the generation that will lead to OH free radical, so monitoring simultaneously
Formaldehyde and glyoxal help completely to understand the OH free radical source (note: OH of the main photodissociation aldehyde contribution in atmosphere
Free radical is most important oxidative free radical in atmosphere)；
(c) nitrogen dioxide (NO2)/nitric oxide (NO)/ozone (O3): where NO2It can directly supervised by this technology
It surveys, NO and O3O is added respectively3And NO, they are separately converted to NO2It monitors again afterwards.The embodiment of the present application is practical to be provided together
When monitor the reference instrument schemes of these three typical atmosphere pollutions；
(d) nitrogen pentoxide (N2O5)/nitrogen peroxide (NO3): both substances are the nitrogen oxides (NO+NO in atmosphere2)
Night is by ozone O3The important activity intermediate of oxidation, helps completely to understand above two nitrogen oxides and exists to their monitoring
Oxidation mechanism in atmosphere and its atmospheric chemistry process (such as N specifically participated in2O5It is converted into nitric acid, NO3Oxidation volatile has
Machine object)；
(e) iodine oxide (IO) and iodine steam (I2): both substances are Marine stratocumulus (MBL, Marine
Boundary Layer) inner important activity intermediate, it has great significance to the ozone depletion in catalysis MBL；
(f) nitrous acid (HONO): in contaminated shallow-layer atmosphere, such as 100-300 meters of urban ground etc. most important OH
Free radical source.In addition to this, the optical cavity for measuring HONO can measure NO simultaneously2, both of which is that the burning of indoor fuel gas stove is released
The important indoor polluted gas released.
(g) aerosol extinction (aerosol extinction): if particulate filter is not added in air inlet
(aerosol filter), then particulate matter can enter delustring caused by cavity and then directly measure is shut out the light as particulate matter
Value.
Wherein, implement the embodiment of the present application, can measure arbitrarily ultraviolet-visible optical band have absorption atmospheric molecule and
Aerosol extinction.In general, the sensitivity of system and method disclosed in the embodiment of the present application is mainly by the following factor
Influence:
(1) height in the characteristic absorption section of molecule.This value is higher, sensitiveer to the detection of the molecule, detection limit
It is lower.
(2) reflectivity of high reflection mirror, transmissivity height.The former determines the optical length that may finally be realized, the latter
Light is then determined when by high reflection mirror, in addition to by reflection, (i.e. 1-R) how many ratio is not damaged lost territory in remaining ratio
Success penetrates convex lens.Therefore, the height that comprehensively consider the two values when high reflection mirror is selected, is reasonably selected.
(3) energy density of the unit area of light source.This value is higher, can be imported into optical fiber and eventually enter into the light of optical cavity
It is strong higher.When final noise is controlled by shot noise (shot noise), light intensity is stronger, and sensitivity is higher.In 330-
In the wave-length coverage of 900nm, the unit area luminous energy and efficiency of light emitting diode (LED) are highest, so generally taking
LED does light source.If desired shorter ultraviolet wavelength is used, is also required to consider other light sources such as deuterium lamp or mercury lamp sometimes.
(4) thermal stability of light source.Since what is surveyed is being inhaled on higher smooth background signal by atmospheric molecule
The variation of the extremely faint signal caused by receiving, the drift of the background signal caused by even very faint light source thermal drift
Shifting is also enough to exceed molecule absorption signal to be measured, and then influences minimum detection limit.When doing light source with LED, generally with thermoelectric cold
But device will do constant temperature to it and wrap up heat insulation foam, its temperature is stablized within 0.01 degree Celsius.
(5) thermal stability and mechanical stability of optical cavity.It is required that the optical cavity of design in variation of ambient temperature, collimates
(alignment) not because expanding with heat and contract with cold for material has significant change.Secondly, it is intracavitary it is outer have pressure difference when (as done aboard
When observation), optical cavity will have enough mechanical strengths, it is ensured that the collimation of two-face mirror does not occur obviously to become because of the extruding of pressure
Change.For example, can use carbon fiber pipe does cavity (because its thermal expansion coefficient is small) or with four carbon fiber pipe supports (because of its density
Small and high mechanical strength) microscope base bracket and optical motion seat shown in upper figure be so that it keeps collimating under pressure difference environment.
The embodiment of the present application further discloses a kind of computer storage medium, and the computer storage medium is based on storing
Calculation machine program, wherein the computer program makes computer execute the atmospheric molecule detection disclosed in the embodiment of the present application
Method.
The embodiment of the present application further discloses a kind of computer program product including instruction, the computer program product
When running on computers, so that the computer executes the atmospheric molecule detection method disclosed in the embodiment of the present application.
The embodiment of the present application further discloses a kind of computer storage medium, and the computer storage medium is based on storing
Calculation machine program, wherein the computer program makes computer execute the high reflection mirror screening disclosed in the embodiment of the present application
Method.
The embodiment of the present application further discloses a kind of computer program product including instruction, the computer program product
When running on computers, so that the computer executes the high reflection mirror screening technique disclosed in the embodiment of the present application.
Those of ordinary skill in the art will appreciate that all or part of the steps in the various methods of above-described embodiment is can
It is completed with instructing relevant hardware by program, which can be stored in a computer readable storage medium, storage
Medium include read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory,
RAM), programmable read only memory (Programmable Read-only Memory, PROM), erasable programmable is read-only deposits
Reservoir (Erasable Programmable Read Only Memory, EPROM), disposable programmable read-only memory (One-
Time Programmable Read-Only Memory, OTPROM), the electronics formula of erasing can make carbon copies read-only memory
(Electrically-Erasable Programmable Read-Only Memory, EEPROM), CD-ROM (Compact
Disc Read-Only Memory, CD-ROM) or other disc memories, magnetic disk storage, magnetic tape storage or can
For carrying or any other computer-readable medium of storing data.
Above to a kind of atmospheric molecule detection system, optical cavity structure, high reflection mirror screening side disclosed in the embodiment of the present application
Method and atmospheric molecule detection method are described in detail, used herein principle and implementation of the specific case to the application
Mode is expounded, the description of the example is only used to help understand the method for the present application and its core ideas；Meanwhile
For those of ordinary skill in the art, according to the thought of the application, has change in specific embodiments and applications
Become place, in conclusion the contents of this specification should not be construed as limiting the present application.
Claims (10)
1. a kind of high reflection mirror screening technique applied to optical cavity structure, which is characterized in that the optical cavity structure includes:
Cavity pipe, the left end of the cavity pipe are equipped with the first high reflection mirror, and the right end of the cavity pipe is equipped with the second high reflection mirror；
The mirror surface of the mirror surface of first high reflection mirror and second high reflection mirror realizes collimation；The outside of first high reflection mirror
Equipped with the first convex lens, the outside of second high reflection mirror is equipped with the second convex lens；The first end of first optical fiber is for connecting
The emission port of light source, the second end of first optical fiber are placed in the outside focus of first convex lens；Second optical fiber
First end for connecting spectrometer, the second end of second optical fiber is placed on the outside focus of second convex lens
On；When being full of the gas of the atmospheric molecule containing concentration undetermined in the cavity pipe, first convex lens is to described first
Inject the cavity pipe after the collimation of light derived from optical fiber so that light after roundtrip is multiple between the high reflection mirror of two sides from
It opens the cavity pipe and is focused on second optical fiber via second convex lens, then import institute via second optical fiber
State spectrometer；
Wherein, the high reflection mirror screening technique, comprising the following steps:
1), according to the photoabsorption cross-section feature of the atmospheric molecule of the concentration undetermined, suitable high reflection mirror is selected, high reflection is made
Wave-length coverage where the reflectivity curve high level end of mirror as far as possible with the central peak wavelength of source emissioning light spectrum and undetermined dense
Wave-length coverage overlapping where the maximum light absorption section of the atmospheric molecule of degree；
2), meeting above-mentioned steps 1) in the case where, it is assumed that the reflectance peak of high reflection mirror is located at wavelength Xmax, reflectivity peak
Value is Rmax, in the wavelength XmaxThe light transmittance at place is that T needs to maximize then in final choice high reflection mirrorValue can be only achieved best sensitivity and signal-to-noise ratio.
2. high reflection mirror screening technique according to claim 1, which is characterized in that the method also includes:
First optical motion seat is set, and the left end of the cavity pipe, and described first is arranged in the first optical motion seat
High reflection mirror is fixed on the first optical motion seat；
The first optical motion seat is equipped with the tilt angle for adjusting first high reflection mirror, so that described first is high
The mirror surface of the mirror surface of reflecting mirror and second high reflection mirror realizes the adjusting screw of collimation.
3. high reflection mirror screening technique according to claim 2, which is characterized in that further include:
Second optical motion seat is set, the outside of the first optical motion seat is arranged in the second optical motion seat, and
First convex lens is fixed on the second optical motion seat；
The second optical motion seat is equipped with for adjusting the first convex lens inclining relative to first high reflection mirror
Rake angle, so that first convex lens and first high reflection mirror realize the adjusting screw of collimation between the two.
4. high reflection mirror screening technique according to claim 3, it is characterised in that:
The second end of first optical fiber is arranged on the second optical motion seat, and on the second optical motion seat also
Equipped with for the distance between the second end of the first optical fiber described in Level tune and first convex lens, so that first light
Fine second end is placed on the optical fiber adjusting knob in the outside focus of first convex lens.
5. according to high reflection mirror screening technique described in claim 2,3 or 4, which is characterized in that the method also includes:
Third optical motion seat is set, and the right end of the cavity pipe, and described second is arranged in the third optical motion seat
High reflection mirror is fixed on the third optical motion seat；
The third optical motion seat is equipped with the tilt angle for adjusting second high reflection mirror, so that described second is high
The mirror surface of the mirror surface of reflecting mirror and first high reflection mirror realizes the adjusting screw of collimation.
6. high reflection mirror screening technique according to claim 5, which is characterized in that the method also includes:
4th optical motion seat is set, the outside of the third optical motion seat is arranged in the 4th optical motion seat, and
Second convex lens is fixed on the 4th optical motion seat；
The 4th optical motion seat is equipped with for adjusting the second convex lens inclining relative to second high reflection mirror
Rake angle, so that second convex lens and second high reflection mirror realize the adjusting screw of collimation between the two.
7. high reflection mirror screening technique according to claim 6, it is characterised in that:
The second end of second optical fiber is arranged on the 4th optical motion seat, and on the 4th optical motion seat also
Equipped with for the distance between the second end of the second optical fiber described in Level tune and second convex lens, so that second light
Fine second end is placed on the optical fiber adjusting knob in the outside focus of second convex lens.
8. high reflection mirror screening technique according to claim 7, which is characterized in that the method also includes::
From the first optical motion seat to set gradually the left end of the cavity pipe the first bellows and the first microscope base and
Chamber mount；
First microscope base and chamber mount are equipped with the air inlet pipe for being pumped into gas to the cavity pipe.
9. high reflection mirror screening technique according to claim 8, which is characterized in that the method also includes:
From the third optical motion seat to set gradually the right end of the cavity pipe the second bellows and the second microscope base and
Chamber mount；
Second microscope base and chamber mount are equipped with for the escape pipe for the cavity pipe output gas.
10. high reflection mirror screening technique according to claim 9, which is characterized in that the method also includes:
The gas blocked in the cavity pipe for inputting purge gass is further set on first microscope base and chamber mount
The first purge gass air inlet pipe that body is directly contacted with the mirror surface of first high reflection mirror；
The gas blocked in the cavity pipe for inputting purge gass is further set on second microscope base and chamber mount
The second purge gass air inlet pipe that body is directly contacted with the mirror surface of second high reflection mirror；
Wherein, the purge gass include pure nitrogen gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811025937.9A CN109100316A (en) | 2018-09-04 | 2018-09-04 | A kind of high reflection mirror screening technique applied to optical cavity structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811025937.9A CN109100316A (en) | 2018-09-04 | 2018-09-04 | A kind of high reflection mirror screening technique applied to optical cavity structure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109100316A true CN109100316A (en) | 2018-12-28 |
Family
ID=64865006
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811025937.9A Pending CN109100316A (en) | 2018-09-04 | 2018-09-04 | A kind of high reflection mirror screening technique applied to optical cavity structure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109100316A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112525838A (en) * | 2020-11-13 | 2021-03-19 | 航天新气象科技有限公司 | Gas pool parameter design method, device and detection system based on absorptiometry |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002026123A1 (en) * | 2000-09-26 | 2002-04-04 | Sensys Medical, Inc. | Led light source-based instrument for non-invasive blood analyte determination |
| CN104237129A (en) * | 2014-10-08 | 2014-12-24 | 上海理工大学 | Sealing adjusting mirror bracket for cavity enhanced spectrum instrument |
| CN104596955A (en) * | 2014-12-11 | 2015-05-06 | 中国科学院合肥物质科学研究院 | Cavity enhanced absorption spectrum device and method for simultaneous measurement of trace gas concentration and aerosol extinction |
| CN104995511A (en) * | 2012-11-16 | 2015-10-21 | 牛津医药有限公司 | Portable breath volatile organic compounds analyzer and corresponding unit |
| CN105043996A (en) * | 2014-04-29 | 2015-11-11 | 邓文平 | Spectral measurement method of spectrograph |
| CN105424631A (en) * | 2015-12-25 | 2016-03-23 | 中国科学院合肥物质科学研究院 | Ultrahigh sensitivity nitrogen oxide measurement system based on ultraviolet-visible waveband absorption spectrum |
| CN106596437A (en) * | 2016-12-30 | 2017-04-26 | 北京大学 | On-line measuring system and on-line measuring method for concentration of NO3 free radicals in atmosphere |
| CN106644986A (en) * | 2016-12-30 | 2017-05-10 | 北京大学 | Online measurement device and measurement method for NO concentration in high-NO2 and low-NO atmosphere |
-
2018
- 2018-09-04 CN CN201811025937.9A patent/CN109100316A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002026123A1 (en) * | 2000-09-26 | 2002-04-04 | Sensys Medical, Inc. | Led light source-based instrument for non-invasive blood analyte determination |
| CN104995511A (en) * | 2012-11-16 | 2015-10-21 | 牛津医药有限公司 | Portable breath volatile organic compounds analyzer and corresponding unit |
| CN105043996A (en) * | 2014-04-29 | 2015-11-11 | 邓文平 | Spectral measurement method of spectrograph |
| CN104237129A (en) * | 2014-10-08 | 2014-12-24 | 上海理工大学 | Sealing adjusting mirror bracket for cavity enhanced spectrum instrument |
| CN104596955A (en) * | 2014-12-11 | 2015-05-06 | 中国科学院合肥物质科学研究院 | Cavity enhanced absorption spectrum device and method for simultaneous measurement of trace gas concentration and aerosol extinction |
| CN105424631A (en) * | 2015-12-25 | 2016-03-23 | 中国科学院合肥物质科学研究院 | Ultrahigh sensitivity nitrogen oxide measurement system based on ultraviolet-visible waveband absorption spectrum |
| CN106596437A (en) * | 2016-12-30 | 2017-04-26 | 北京大学 | On-line measuring system and on-line measuring method for concentration of NO3 free radicals in atmosphere |
| CN106644986A (en) * | 2016-12-30 | 2017-05-10 | 北京大学 | Online measurement device and measurement method for NO concentration in high-NO2 and low-NO atmosphere |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112525838A (en) * | 2020-11-13 | 2021-03-19 | 航天新气象科技有限公司 | Gas pool parameter design method, device and detection system based on absorptiometry |
| CN112525838B (en) * | 2020-11-13 | 2022-12-09 | 航天新气象科技有限公司 | Gas pool parameter design method, device and detection system based on absorptiometry |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Ruddy et al. | Evanescent wave absorption spectroscopy using multimode fibers | |
| US7710566B2 (en) | Method and apparatus for photoacoustic measurements | |
| US5281816A (en) | Method and apparatus for detecting hydrocarbon vapors in a monitored area | |
| Mi et al. | Silicon microring refractometric sensor for atmospheric CO 2 gas monitoring | |
| US5734165A (en) | Microstructured infrared absorption photometer | |
| US8139222B2 (en) | Pressure controlled spectroscopic heating value sensor | |
| FI95322C (en) | Spectroscopic measuring sensor for analyzing media | |
| US7298490B2 (en) | Hydrogen sensor based upon quadrupole absorption spectroscopy | |
| CN108956503A (en) | A kind of hydrone density calculating method | |
| US4553032A (en) | Infrared energy gage | |
| CN109187355A (en) | A kind of purging gas path device applied to optical cavity structure | |
| Thompson et al. | A fixed frequency aerosol albedometer | |
| CN109100316A (en) | A kind of high reflection mirror screening technique applied to optical cavity structure | |
| KR20010034643A (en) | Device and method for directly measuring calorific energy contained in a fuel gas | |
| CN103257125B (en) | For measuring the method for CO2 content and the sensor of fluid | |
| CN109211807A (en) | A kind of atmospheric molecule detection system having pre-reformer before gas is examined | |
| US6118134A (en) | Optical mass gauge sensor having an energy per unit area of illumination detection | |
| CN109115683A (en) | The installation method of convex lens and high reflection mirror in a kind of optical cavity structure | |
| CN108956475A (en) | A kind of optical cavity structure | |
| CN109115706A (en) | A kind of temperature correction method of hydrone absorption coefficient | |
| CN109001132A (en) | A kind of atmospheric molecule detection method | |
| CN108956471A (en) | The installation method of convex lens and optical fiber in a kind of optical cavity structure | |
| CN109060691A (en) | A kind of calculation method and equipment of atmospheric molecule concentration | |
| CN109238975A (en) | The compatible gas circuit structure for flowing backward zero gas in a kind of atmospheric molecule detection system | |
| CN109187344A (en) | A kind of gas circuit structure applied to atmospheric molecule detection system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20181228 |
|
| RJ01 | Rejection of invention patent application after publication |