CN103335967B - Fiber loop cavity ringdown spectroscopy device based on Brillouin slow light effect - Google Patents
Fiber loop cavity ringdown spectroscopy device based on Brillouin slow light effect Download PDFInfo
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- 239000000835 fiber Substances 0.000 title claims abstract description 57
- 238000000180 cavity ring-down spectroscopy Methods 0.000 title claims abstract description 19
- 230000001795 light effect Effects 0.000 title claims abstract description 17
- 230000003287 optical effect Effects 0.000 claims abstract description 75
- 238000005259 measurement Methods 0.000 claims abstract description 11
- 230000005540 biological transmission Effects 0.000 claims description 14
- 230000000694 effects Effects 0.000 claims description 4
- 238000001514 detection method Methods 0.000 abstract description 24
- 238000005516 engineering process Methods 0.000 abstract description 13
- 238000005086 pumping Methods 0.000 abstract description 4
- 230000035945 sensitivity Effects 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 3
- 239000013307 optical fiber Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 238000004611 spectroscopical analysis Methods 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000000862 absorption spectrum Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000002310 reflectometry Methods 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000010453 quartz Substances 0.000 description 1
- 230000001953 sensory effect Effects 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
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Abstract
The invention discloses a fiber loop cavity ringdown spectroscopy device based on the Brillouin slow light effect. The fiber loop cavity ringdown spectroscopy device has the structural characteristics that a tunable narrow linewidth pumping laser device and a photoelectric detector are connected with an optical circulator I; the optical circulator I is connected with an optical coupler I; an optical coupler II, an optical isolator, an optical modulator and a tunable detection laser device are sequentially connected in series; an optical circulator II, an optical circulator III, an optical coupler II and an optical coupler I are clockwise sequentially connected with a fiber loop cavity; and an optical sensing head is connected with the optical circulator II and the optical circulator III. According to the device disclosed by the invention, by adopting the Brillouin slow light effect, the system introduces the pumping light in a direction opposite to the detection light, and adjusts the frequency of the pumping light and the detection light so as to generate stimulated Brillouin scattering. The stimulated Brillouin scattering enables the detection light to generate a slow light effect, thus the propagation speed of the detection light in the fiber loop cavity is reduced, and the measurement sensitivity of the fiber loop cavity ringdown spectroscopy technology is greatly improved.
Description
Technical field
The present invention relates to a kind of fiber annular cavity ring-down spectroscopy device based on Brillouin's slow light effect.
Background technology
Fiber annular cavity ring-down spectroscopy technology is as one of spectrum test technology, Research on Cavity Ring Down Spectroscopy is highly sensitive with it, by the impact of light source light-intensity variation and the advantage such as antijamming capability is strong, attract wide attention, one of technical way becoming trace detection;
In fiber annular cavity ring-down spectroscopy technology, optic fiber ring-shaped cavity ring-down time constant is
Wherein, L is that the chamber of optic fiber ring-shaped cavity is long, and V is the velocity of propagation of light in optical fiber, and T is the loss that optic fiber ring-shaped cavity center tap (connection etc. as optical circulator, photo-coupler and optical pickup and optical fiber) is introduced, α
fit is fibre loss coefficient.Therefore, chamber is longer, and ring-down time constant is longer; The loss in chamber is less, and ring-down time is longer; Light velocity of propagation is slower, and ring-down time is longer;
For fiber annular cavity ring-down spectroscopy technology, its measurement sensistivity is
Wherein, Δ τ is the difference adding test substance back cavity ring-down time constant Yu do not add test substance cavity-type BPM time constant;
Can be obtained by (1) formula and (2) formula
Therefore, in fiber annular cavity ring-down spectroscopy technology, the velocity of propagation of light in chamber is less, and measurement sensistivity is higher; The loss in chamber is less, and measurement sensistivity is higher; Chamber is longer, and measurement sensistivity is higher;
At present, proposed by the method increasing chamber length and (mainly through improving the reflectivity of chamber mirror) the two kinds of modes that reduce the wastage improve the sensitivity in chamber.But chamber is longer, and system bulk is larger, and be subject to the impact of extraneous factor.Then there is a limit in cavity mirrors reflectivity, is difficult to continue to improve; Therefore, the ring-down spectroscopy technology based on optic fiber ring-shaped cavity is suggested.Ring-down spectroscopy technology based on optic fiber ring-shaped cavity can offset the loss of optic fiber ring-shaped cavity by introducing Erbium-Doped Fiber Amplifier (EDFA) in chamber, therefore, the ring-down spectroscopy technical feature based on optic fiber ring-shaped cavity is only limited to the length of optic fiber ring-shaped cavity.But the same with other chamber, the chamber of optic fiber ring-shaped cavity is longer, and the interference by extraneous factor is larger.Slow light effect causes the attention of people in the application of sensory field, but in Research on Cavity Ring Down Spectroscopies all at present, slow light effect is all the effective length for increasing light and material effect, and is not based on Brillouin's slow light effect.
Summary of the invention
The object of the present invention is to provide a kind of fiber annular cavity ring-down spectroscopy device based on Brillouin's slow light effect, it has the advantage of the measurement sensistivity greatly improving fiber annular cavity ring-down spectroscopy technology.
The present invention is achieved like this, it comprises tunable narrow-linewidth pump laser, photodetector, optical circulator I, photo-coupler I, photo-coupler II, optoisolator, photomodulator, tunable detecting laser, optic fiber ring-shaped cavity, optical circulator II, optical pickup and optical circulator III, it is characterized in that tunable narrow-linewidth pump laser is connected with optical circulator I with photodetector, optical circulator I connects photo-coupler I, photo-coupler II, optoisolator, photomodulator and tunable detecting laser are connected successively, optical circulator II, optical circulator III, photo-coupler II and photo-coupler I are connected in turn on optic fiber ring-shaped cavity along clockwise direction, optical pickup is connected with optical circulator III with optical circulator II, described optical circulator I is counterclockwise transmission, described optical circulator II and optical circulator III are clockwise direction transmission, described photo-coupler I and the splitting ratio of photo-coupler II are 1:99.There is the two-beam of clockwise direction and counterclockwise transmission in described optic fiber ring-shaped cavity, the light of wherein clockwise direction transmission enters sensing head, and the light of counterclockwise transmission does not enter optical pickup.Under excited Brillouin effect, the transmission speed of the light of described clockwise direction transmission is slack-off, thus the cavity-type BPM time constant of the light that described clockwise direction is transmitted is elongated, finally improves measurement sensistivity.
For stimulated Brillouin scattering, the difference on the frequency of pump light and detection light equals Brillouin shift.For conventional quartz single-mode fiber, Brillouin shift is roughly at about 11GHz, and like this, if pump light and detection light all enter sensing head, the frequency that likely there will be pump light and detection light is in a certain absorption peak of tested gas simultaneously;
Because the difference on the frequency of pump light and detection light only has about 11GHz, be difficult to separately with general optical filter, therefore, the key based on the fiber annular cavity ring-down spectroscopy technology of Brillouin's slow light effect only allows detection light enter sensing head, namely only allows detection light and material produce and interact.Based on this, the present invention passes through appropriate design, introduce optical circulator, make pump light only circulating propagation in the counterclockwise direction in optic fiber ring-shaped cavity, do not enter sensing head, and detect light not only circulating propagation along clockwise direction in optic fiber ring-shaped cavity, also can enter optical pickup simultaneously, successfully avoid the excess loss that pump light causes due to the absorption of measured target through optical pickup;
Simultaneously, in order to obtain the absorption spectra of measured matter, the present invention utilizes the principle of Brillouin's slow light effect frequency-adjustable, by regulating tunable narrow-linewidth pump laser and tunable detecting laser (only need ensure that the difference on the frequency of the pump light that tunable narrow-linewidth pump laser exports and the detection light that tunable detecting laser exports equals Brillouin shift) simultaneously, thus realize the scanning to measured matter absorption spectra;
For achieving the above object, using method of the present invention is:
The first, pump light circulating propagation in the counterclockwise direction in optic fiber ring-shaped cavity of exporting of tunable narrow-linewidth pump laser;
The second, the detecting optical pulses that tunable detecting laser exports enters optic fiber ring-shaped cavity along clockwise direction, through optical circulator II laggard enter optical pickup, enter optic fiber ring-shaped cavity along clockwise direction from sensing head light out again through optical circulator III;
Three, regulate tunable narrow-linewidth pump laser and tunable detecting laser, make its difference on the frequency equal Brillouin shift, then anticlockwise pump light and clockwise detection light can produce stimulated Brillouin scattering;
By stimulated Brillouin scattering, the light velocity of detection light can be slack-off, thus improve measurement sensistivity.
Technique effect of the present invention is: the present invention is by adopting Brillouin's slow light effect, and system, introducing pump light with detection light reverse direction, regulates the frequency of pump light and detection light, makes it produce stimulated Brillouin scattering.Stimulated Brillouin scattering makes detection light produce slow light effect, detects the velocity of propagation of light in optic fiber ring-shaped cavity so slack-off, thus greatly improves the measurement sensistivity of fiber annular cavity ring-down spectroscopy technology.Improve the measurement sensistivity of fiber annular cavity ring-down spectroscopy technology.
Accompanying drawing explanation
Fig. 1 is structural representation of the present invention.
In the drawings, 1, tunable narrow-linewidth pump laser 2, photodetector 3, optical circulator I 4, photo-coupler I 5, photo-coupler II 6, optoisolator 7, photomodulator 8, tunable detecting laser 9, optic fiber ring-shaped cavity 10, optical circulator II 11, optical pickup 12, optical circulator III.
Embodiment
As shown in Figure 1, the present invention is achieved like this, it comprises tunable narrow-linewidth pump laser 1, photodetector 2, optical circulator I 3, photo-coupler I 4, photo-coupler II 5, optoisolator 6, photomodulator 7, tunable detecting laser 8, optic fiber ring-shaped cavity 9, optical circulator II 10, optical pickup 11 and optical circulator III 12, its design feature is that tunable narrow-linewidth pump laser 1 is connected with optical circulator I 3 with photodetector 2, optical circulator I 3 connects photo-coupler I 4, photo-coupler II 5, optoisolator 6, photomodulator 7 and tunable detecting laser 8 are connected successively, optical circulator II 10, optical circulator III 12, photo-coupler II 5 and photo-coupler I 1 are connected in turn on optic fiber ring-shaped cavity 9 along clockwise direction, optical pickup 11 is connected with optical circulator III 12 with optical circulator II 10, described optical circulator I 3 is counterclockwise transmission, described optical circulator II 10 and optical circulator III 12 are clockwise direction transmission, described photo-coupler I 4 and the splitting ratio of photo-coupler II 5 are 1:99,
Principle of work of the present invention and using method are:
1, it is 1:99 that the pump light that tunable narrow-linewidth pump laser 1 exports enters photo-coupler I 4(splitting ratio again after anticlockwise optical circulator I 3), then enter optic fiber ring-shaped cavity 9, circulate in the counterclockwise direction in optic fiber ring-shaped cavity 9;
2, the detection light that tunable detecting laser 8 sends becomes pulsed light after photomodulator 7, through optoisolator 6 laggard enter photo-coupler 5(splitting ratio be 1:99), then enter optic fiber ring-shaped cavity along clockwise direction.Detection light in optic fiber ring-shaped cavity first through photo-coupler 4, then through optical circulator 10 laggard enter optical pickup 11.Enter optical circulator 12 afterwards, enter optic fiber ring-shaped cavity along clockwise direction by optical circulator 12, then enter photo-coupler II 5.Then next one circulation is carried out;
3, tunable narrow-linewidth pump laser 1 is regulated, and make the pumping light power in optic fiber ring-shaped cavity be greater than the threshold value producing stimulated Brillouin scattering, when pump light and the difference of frequency of detection light equal Brillouin shift in optical fiber (for conventional single mode silica fibre, Brillouin shift is roughly at about 11GHz) time, stimulated Brillouin scattering will be produced, produce slow light effect, thus cause the velocity of propagation detecting light slack-off.
4, after setting up laser generation in optic fiber ring-shaped cavity 9, quick closedown is tunable detecting laser 8.At this moment, pump laser is still in work, and like this, the detection light of decay still can cause it to slow due to stimulated Brillouin scattering, records declining of light of detection and swings curve, can obtain the ring-down time constant of optic fiber ring-shaped cavity 9 by photodetector 2.
5, regulate the frequency of tunable narrow-linewidth pump laser 1 and tunable detecting laser 8, but difference on the frequency remains unchanged.
6, repeat the 4th and the 5th step, declining of light of different frequency detection can be recorded and swing curve, thus obtain the absorption line of measured target and the concentration of measured target.
Claims (2)
1. the fiber annular cavity ring-down spectroscopy device based on Brillouin's slow light effect, it comprises tunable narrow-linewidth pump laser, photodetector, optical circulator I, photo-coupler I, photo-coupler II, optoisolator, photomodulator, tunable detecting laser, optic fiber ring-shaped cavity, optical circulator II, optical pickup and optical circulator III, it is characterized in that tunable narrow-linewidth pump laser is connected with optical circulator I with photodetector, optical circulator I connects photo-coupler I, photo-coupler II, optoisolator, photomodulator and tunable detecting laser are connected successively, optical circulator II, optical circulator III, photo-coupler II and photo-coupler I are connected in turn on optic fiber ring-shaped cavity along clockwise direction, optical pickup is connected with optical circulator III with optical circulator II, the two-beam of clockwise direction and counterclockwise transmission is there is in described optic fiber ring-shaped cavity, after wherein the light of clockwise direction transmission enters photo-coupler II, light is along the direction of arrow in photo-coupler II, export from the lower Single port of photo-coupler II, then enter optical pickup, enter photo-coupler III from optical pickup light out, then along the direction of arrow in photo-coupler III, export from the lower Single port of photo-coupler III, finally enter optic fiber ring-shaped cavity along clockwise direction, after counterclockwise the light of transmission enters photo-coupler III, light is along the direction of arrow in photo-coupler III, export from the lower Single port of photo-coupler III, then photo-coupler II is directly entered, again along the direction of arrow in photo-coupler II, export from the lower Single port of photo-coupler II, finally enter optic fiber ring-shaped cavity in the counterclockwise direction, do not enter optical pickup.
2. as claimed in claim 2 based on the fiber annular cavity ring-down spectroscopy device of Brillouin's slow light effect, it is characterized in that under excited Brillouin effect, the transmission speed of the light of described clockwise direction transmission is slack-off, thus the cavity-type BPM time constant of the light making described clockwise direction transmit is elongated, finally improves measurement sensistivity.
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| CN103542872B (en) * | 2013-10-24 | 2015-12-30 | 华南师范大学 | Based on distributed fiberoptic sensor and the method for sensing of excited Brillouin slow light effect |
| CN106950194B (en) * | 2017-03-17 | 2018-06-12 | 哈尔滨翰奥科技有限公司 | Gas sensor and the method for detecting concentration of SO 2 gas variation |
| CN114486792B (en) * | 2022-01-17 | 2023-08-08 | 吉林大学 | Photo-thermal interference spectrum gas sensing device and detection method based on near infrared dual-wavelength photonic crystal slow optical waveguide |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101483315A (en) * | 2009-01-23 | 2009-07-15 | 清华大学 | Optical fiber Brillouin laser for bi-directional dual wavelength lasing |
| CN101629852A (en) * | 2009-08-19 | 2010-01-20 | 南昌航空大学 | Method for eliminating temperature and stress backward influence effect in Brillouin optical-fiber sensing |
| CN102967371A (en) * | 2012-11-30 | 2013-03-13 | 哈尔滨理工大学 | Device and method for measuring brillouin gain spectrum in non-scanning manner based on pumping-detection method |
| CN103090894A (en) * | 2013-01-10 | 2013-05-08 | 中国人民解放军国防科学技术大学 | Distributed optical fiber sensing device and method based on Brillouin Er-doped fiber laser |
| CN103115632A (en) * | 2013-01-24 | 2013-05-22 | 南京大学（苏州）高新技术研究院 | Multi-wavelength brillouin optical time domain analyzer |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4775173B2 (en) * | 2006-08-24 | 2011-09-21 | 住友電気工業株式会社 | Fiber optic temperature sensor |
| US20120219285A1 (en) * | 2011-02-28 | 2012-08-30 | David Jimmy Dahan | In-band optical signal to noise ratio monitoring technique |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101483315A (en) * | 2009-01-23 | 2009-07-15 | 清华大学 | Optical fiber Brillouin laser for bi-directional dual wavelength lasing |
| CN101629852A (en) * | 2009-08-19 | 2010-01-20 | 南昌航空大学 | Method for eliminating temperature and stress backward influence effect in Brillouin optical-fiber sensing |
| CN102967371A (en) * | 2012-11-30 | 2013-03-13 | 哈尔滨理工大学 | Device and method for measuring brillouin gain spectrum in non-scanning manner based on pumping-detection method |
| CN103090894A (en) * | 2013-01-10 | 2013-05-08 | 中国人民解放军国防科学技术大学 | Distributed optical fiber sensing device and method based on Brillouin Er-doped fiber laser |
| CN103115632A (en) * | 2013-01-24 | 2013-05-22 | 南京大学（苏州）高新技术研究院 | Multi-wavelength brillouin optical time domain analyzer |
Non-Patent Citations (2)
| Title |
|---|
| 《基于光纤环形腔衰落的压力传感器研究》;张卫华等;《光子学报》;20080331;第37卷(第3期);第466-468页 * |
| 《基于布里渊散射的光纤传感***性能分析》;万生鹏等;《传感技术学报》;20040630(第2期);第322-324页 * |
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