CN104697933B - Triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device - Google Patents
Triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device Download PDFInfo
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- CN104697933B CN104697933B CN201510096806.XA CN201510096806A CN104697933B CN 104697933 B CN104697933 B CN 104697933B CN 201510096806 A CN201510096806 A CN 201510096806A CN 104697933 B CN104697933 B CN 104697933B
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Abstract
The invention discloses a kind of triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device.It includes the laser controller (2) and the control signal source that are electrically connected with laser successively, and the tubulose acoustic resonant cavity that is communicated with acoustic conducting pipe coaxial with laser light path, it is placed in the acoustic sensor (5) of its output end electrical connection lock-in amplifier (6) of acoustic conductance pipe port, particularly laser, laser controller (2) and it is three as the signal generator (1) in control signal source, tubulose acoustic resonant cavity is by cylinder (7), its tubulose cavity axis is constituted with three resonators of cylinder (7) diameter parallel, the pipe port of three acoustic conducting pipes is respectively positioned on the sensitive face of acoustic sensor (5), three signal output parts of three passage tapped off signal generator (1) of lock-in amplifier (6), the three road photoacoustic spectrum signals for going out acoustic sensor (5) perception by demodulation reference signal.Three kinds of components in its energy synchronous real-time measurement gas.
Description
Technical field
The present invention relates to a kind of optoacoustic spectroscopy sensing device, especially a kind of triple channel acoustic resonant cavity optoacoustic spectroscopy sensing
Device.
Background technology
Optoacoustic spectroscopy is a kind of spectral technique based on optoacoustic effect, detection be the light energy that is absorbed by the sample rather than
Transmitted light intensity.When the light source in molecule absorption wave band is irradiated on sample, sample molecule absorbs light energy and transits to sharp
Hair state, the molecule in excitation state returns to ground state by collision relaxation, while the light energy for absorbing is converted into the interior energy of molecule, and
The local temperature of molecule is caused to raise.So when the light being irradiated on sample molecule is modulated, the local temperature of molecule is just
Periodically change can be produced, so as to produce periodic pressure change, i.e. sound wave.When with acoustic sensor record acoustical signal with
During the variation relation of optical source wavelength, photoacoustic spectrum signals have just been obtained.Due to optoacoustic spectroscopy photoacoustic signal only with material to light
Absorption it is relevant, do not influenceed by the scattering factor such as light, therefore be well suited for for the detection to material optical absorption characteristics, such as China
A kind of optoacoustic spectroscopy gas sensor that patent of invention CN 102954948B were announced on November 12nd, 2014.The patent of invention
Using the T-shaped acoustic resonance cavity being made up of supervisor and branch pipe vertical connection, and make the pipe axis of supervisor coaxial with light source optical path, light path
On the focus of condenser lens be located at supervisor and the connectivity part of branch pipe, as the quartz tuning-fork of sonic transducer prong plane and
Slit center respectively with the axis perpendicular of branch pipe and the structure on axis；During detection, by T-shaped acoustic resonance cavity to optoacoustic
The acoustic resonance of signal amplifies, and detects and determine the content of trace gas.Though it can in maximum efficiency realize that light excites sound wave
Coupling between energy and quartz tuning-fork, for detection trace gas field, be but difficult to multi-wavelength under test gas,
Multi-component synchronous real-time measurement.In reality, realized to different component in gas using same optoacoustic spectroscopy gas sensor
The demand of synchronous real-time measurement be objective reality, such as in the research of aerosol absorption characteristic, just need to be to the suction of aerosol
Receiving characteristic carries out multi-wavelength synchro measure, and then analyzes the wavelength-dependent behavior of its absorption, aerosol absorptionSystem
Number etc..
The content of the invention
The technical problem to be solved in the present invention is to overcome shortcoming part of the prior art, there is provided one kind can be surveyed synchronously in real time
The triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device of various ingredients in amount gas.
Be to solve technical problem of the invention, the technical scheme for being used for：Triple channel acoustic resonant cavity optoacoustic spectroscopy is passed
Induction device includes the laser controller and the control signal source that are electrically connected with laser successively, and the company coaxial with laser light path
The tubulose acoustic resonant cavity that is connected with acoustic conducting pipe, the acoustic sensor for being placed in acoustic conductance pipe port and acoustic sensor output end are electrically connected
The lock-in amplifier for connecing, particularly,
The laser is first laser device, second laser and the 3rd laser, its input tap laser controller
The first control output end, the second control output end and the 3rd control output end；
The control signal source is signal generator, its first signal output part, secondary signal output end and the 3rd signal
Output end taps the respective input of laser controller；
The tubulose acoustic resonant cavity is humorous by cylinder, its tubulose cavity axis parallel with cylinder axis first
Shake chamber, the second resonator and the 3rd resonator composition, wherein, the first cavity length L1, the second cavity length L2 and the 3rd
Relation between cavity length L3 is L1<L3<L2, the radial direction angle between the first resonator, the 3rd resonator and the second resonator
It is 85~95 degree；
The acoustic conducting pipe is the first acoustic conducting pipe, the second acoustic conducting pipe and the 3rd acoustic conducting pipe, first acoustic conducting pipe, the second acoustic conductance
The pipe port of pipe and the 3rd acoustic conducting pipe is respectively positioned on the sensitive face of the acoustic sensor, wherein, the first acoustic conducting pipe, the 3rd acoustic conductance
The pipe axis of pipe and the angle of the sensitive face are 40~50 degree, the pipe axis of the second acoustic conducting pipe and the angle of the sensitive face
It is 85~95 degree；
First letter of the first passage, second channel and the third channel tap signal generator of the lock-in amplifier
Number output end, secondary signal output end and the 3rd signal output part, the reference signal for receiving signal generator offer, to solve
Photoacoustic spectrum signals in the corresponding resonator of voicing sensor senses.
As the further improvement of triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device：
Preferably, laser is semiconductor laser, or QCL, or optical parametric oscillation light source.
Preferably, the first cavity length L1 >=5cm, the second cavity length L2≤35cm.
Preferably, the tubular cavity diameter of the first resonator, the second resonator and the 3rd resonator is 1~15mm.
Preferably, the center of the tubulose cavity axis of the first resonator, the second resonator and the 3rd resonator is in same
On circumference.
Preferably, the first acoustic conducting pipe, the second acoustic conducting pipe and the 3rd acoustic conducting pipe respectively with the first resonator, the second resonator and
3rd resonator vertical connection, and its connectivity part is respectively positioned on the midpoint of corresponding resonator.
Preferably, acoustic sensor is tuning fork, or microphone, or poly meta fluoroethylene piezoelectric film.
Preferably, the tubulose acoustic resonant cavity of cylindrical shape is disposed thereon is equipped with incidence window, exit window and enters respectively
In sample mouthful, outlet, and preceding surge chamber, the photoacoustic cell of rear surge chamber.
Beneficial effect relative to prior art is：
After such structure, the present invention can it is separate, do not interfere with each other and synchronous real-time measurement three without distortion
The photoacoustic signal of resonator.It realizes many ripples with just settling at one go under conditions of using only an optoacoustic spectroscopy sensing device
Long, multi-component synchro measure, and each passage works in respective optimum frequency, while synchro measure is ensured, both
There is provided optimal detection performance and detectivity, and the volume of measuring system and the volume of sample are greatly reduced, from
And greatly extend its applicable scope.
Brief description of the drawings
Fig. 1 is a kind of basic structure schematic diagram of the invention.
Fig. 2 is triple channel acoustic resonant cavity and corresponding acoustic conducting pipe in the present invention, and the connection between acoustic sensor
Connection diagram.
Fig. 3 is the distribution of lengths schematic diagram of triple channel acoustic resonant cavity in the present invention.
Fig. 4 is the frequency characteristic curve diagram of triple channel acoustic resonant cavity in the present invention.
Specific embodiment
Preferred embodiment of the invention is described in further detail below in conjunction with the accompanying drawings.
Referring to Fig. 1, Fig. 2 and Fig. 3, the composition of triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device is as follows：
First laser device 301, the input of the laser 303 of second laser 302 and the 3rd are sequentially connected electrically laser respectively
First control output end 201 of controller 2, the second control output end 202 and the 3rd control output end 203, and signal occur
First signal output part 101 of device 1, the signal output part 103 of secondary signal output end 102 and the 3rd；Wherein, three lasers are equal
It is semiconductor laser (or QCL, or optical parametric oscillation light source).
First laser device light path 311, the laser light path of second laser light path 312 and the 3rd with above three laser
The 313 coaxial tubulose acoustic resonant cavities for being communicated with acoustic conducting pipe by cylinder 7, its tubulose cavity axis with the axle of cylinder 7
The first parallel resonator 401 of line, the second resonator 402 and the 3rd resonator 403 are constituted.Wherein, the length of the first resonator 401
Relation between L1, the length L2 of the second resonator 402 and the length L3 of the 3rd resonator 403 is L1<L3<L2, now chooses the first resonance
The length L1 of chamber 401 is that 5cm, the length L2 of the second resonator 402 are that 35cm, the length L3 of the 3rd resonator 403 are 15cm；First resonance
The tubular cavity diameter in chamber 401, the second resonator 402 and the 3rd resonator 403 is 10 (can be 1~15) mm；First resonator
401st, the center of the tubulose cavity axis of the second resonator 402 and the 3rd resonator 403 is on same circumference, the first resonator
401st, the radial direction angle between the 3rd resonator 403 and the second resonator 402 is 90 (can be 85~95) degree.
It is the first acoustic conducting pipe 441, the second acoustic conducting pipe 442 and the 3rd sound with the acoustic conducting pipe that above three resonator is respectively communicated with
Conduit 443；Wherein, the first acoustic conducting pipe 441, the second acoustic conducting pipe 442 and the 3rd acoustic conducting pipe 443 respectively with the first resonator 401,
Two resonators 402 and the vertical connection of the 3rd resonator 403, and its connectivity part is respectively positioned on the midpoint of corresponding resonator.First acoustic conductance
The pipe port of pipe 441, the second acoustic conducting pipe 442 and the 3rd acoustic conducting pipe 443 is respectively positioned on the sensitive face of acoustic sensor 5；Wherein,
One acoustic conducting pipe 441, the pipe axis of the 3rd acoustic conducting pipe 443 and the angle of sensitive face are 45 (can be 40~50) degree, the second acoustic conductance
The pipe axis of pipe 442 is 90 (can be 85~95) degree with the angle of sensitive face.
Acoustic sensor 5 is microphone (or tuning fork, or poly meta fluoroethylene piezoelectric film), its output end and lock-in amplifier
6 input electrical connection.
The of the first passage 601 of lock-in amplifier 6, second channel 602 and the tapped off signal generator 1 of third channel 603
One signal output part 101, the signal output part 103 of secondary signal output end 102 and the 3rd, provide for receiving signal generator 1
Reference signal, with demodulate acoustic sensor 5 perception corresponding resonator in photoacoustic spectrum signals.
The tubulose acoustic resonant cavity of the shape of cylinder 7 is disposed thereon to be equipped with incidence window 421, exit window 422 and enters respectively
In sample mouthful 411, outlet 412, and the photoacoustic cell 4 of preceding surge chamber 431, rear surge chamber 432.
When using, under test gas respectively enter tubulose acoustics via the injection port 411 and preceding surge chamber 431 on photoacoustic cell 4
First resonator 401 of resonator, the second resonator 402 and the 3rd resonator 403, and with approach its tubular cavity in through signal
The first laser of first signal output part 101, secondary signal output end 102 and the modulation of the 3rd signal output part 103 of generator 1
After device light path 311, second laser light path 312 and the 3rd laser light path 313 interact, generate periodic pressure and become
Change --- sound wave.The sound wave --- photoacoustic signal is conveyed by the first acoustic conducting pipe 441, the second acoustic conducting pipe 442 and the 3rd acoustic conducting pipe 443
On acoustic sensor 5 to its pipe port, thus photoacoustic signal is converted to and be sent to after electric signal lock and mutually put by acoustic sensor 5
The first passage 601 of device 6, second channel 602 and third channel 603, obtain as or are similar to the frequency characteristic in Fig. 4 greatly
Three kinds of contents of component in shown under test gas.
Obviously, those skilled in the art can enter to triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device of the invention
The various changes of row and modification are without departing from the spirit and scope of the present invention.So, if to these modifications of the invention and modification
Belong within the scope of the claims in the present invention and its equivalent technologies, then the present invention is also intended to exist comprising these changes and modification
It is interior.
Claims (8)
1. a kind of triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device, including the laser controller for being electrically connected with laser successively
(2) and control signal source, and the tubulose acoustic resonant cavity that is communicated with acoustic conducting pipe coaxial with laser light path, it is placed in acoustic conducting pipe
The lock-in amplifier (6) that the acoustic sensor (5) of port is electrically connected with acoustic sensor (5) output end, it is characterised in that：
The laser is first laser device (301), second laser (302) and the 3rd laser (303), its input tap
First control output end (201) of laser controller (2), the second control output end (202) and the 3rd control output end (203)；
The control signal source be signal generator (1), its first signal output part (101), secondary signal output end (102) and
The respective input of the 3rd signal output part (103) tap laser controller (2)；
The tubulose acoustic resonant cavity is by cylinder (7), its tubulose cavity axis with the first of cylinder (7) diameter parallel
Resonator (401), the second resonator (402) and the 3rd resonator (403) composition, wherein, the first resonator (401) length L1,
Relation between the second resonator (402) length L2 and the 3rd resonator (403) length L3 is L1<L3<L2, the first resonator
(401), the radial direction angle between the 3rd resonator (403) and the second resonator (402) is 85~95 degree；
The acoustic conducting pipe is the first acoustic conducting pipe (441), the second acoustic conducting pipe (442) and the 3rd acoustic conducting pipe (443), first acoustic conductance
The pipe port of pipe (441), the second acoustic conducting pipe (442) and the 3rd acoustic conducting pipe (443) is respectively positioned on the sensing of the acoustic sensor (5)
On face, wherein, the first acoustic conducting pipe (441), the pipe axis of the 3rd acoustic conducting pipe (443) are 40~50 with the angle of the sensitive face
Degree, pipe axis and the angle of the sensitive face of the second acoustic conducting pipe (442) are 85~95 degree；
The first passage (601) of the lock-in amplifier (6), second channel (602) and third channel (603) tap the signal
First signal output part (101) of generator (1), secondary signal output end (102) and the 3rd signal output part (103), are used for
The reference signal that signal generator (1) is provided is received, with the light acousto-optic in the corresponding resonator for demodulating acoustic sensor (5) perception
Spectrum signal.
2. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that laser is half
Conductor laser, or QCL, or optical parametric oscillation light source.
3. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that the first resonator
(401) length L1 >=5cm, the second resonator (402) length L2≤35cm.
4. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that the first resonator
(401), the tubular cavity diameter of the second resonator (402) and the 3rd resonator (403) is 1~15mm.
5. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that the first resonator
(401), the center of the tubulose cavity axis of the second resonator (402) and the 3rd resonator (403) is on same circumference.
6. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that the first acoustic conducting pipe
(441), the second acoustic conducting pipe (442) and the 3rd acoustic conducting pipe (443) respectively with the first resonator (401), the second resonator (402) and
3rd resonator (403) vertical connection, and its connectivity part is respectively positioned on the midpoint of corresponding resonator.
7. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that acoustic sensor
(5) it is tuning fork, or microphone, or poly meta fluoroethylene piezoelectric film.
8. triple channel acoustic resonant cavity optoacoustic spectroscopy sensing device according to claim 1, it is characterized in that cylinder (7) shape
Tubulose acoustic resonant cavity disposed thereon be equipped with incidence window (421), exit window (422) and injection port (411) respectively, go out sample
In mouth (412), and the photoacoustic cell (4) of preceding surge chamber (431), rear surge chamber (432).
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108593763B (en) * | 2018-03-26 | 2021-03-30 | 山东大学 | Real-time detection device for multi-component gas based on quartz tuning fork frequency division demodulation |
| CN111122445A (en) * | 2018-11-01 | 2020-05-08 | 西安电子科技大学 | Multiple resonance type T-shaped enhanced simultaneous detection method for multiple trace gases |
| CN111122444A (en) * | 2018-11-01 | 2020-05-08 | 西安电子科技大学 | Multiple resonant T-shaped enhanced multiple trace gas simultaneous detection device |
| CN113295628A (en) * | 2020-02-23 | 2021-08-24 | 亘冠智能技术（杭州）有限公司 | Device for simultaneously detecting black carbon, organic carbon and gas |
| CN112924388B (en) * | 2021-01-22 | 2023-08-25 | 中国科学院合肥物质科学研究院 | Orthogonal double-channel acoustic resonance device |
| CN112858184B (en) * | 2021-01-29 | 2022-07-19 | 山西大学 | Gas measuring device and method based on piezoelectric material |
| CN113109268B (en) * | 2021-05-25 | 2022-07-01 | 武汉理工大学 | Photoacoustic spectroscopy enhancement apparatus and method for gas detection using the same |
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