Abstract

Standoff detections of explosives using quantum cascade lasers (QCLs) and the photoacoustic (PA) technique were studied. In our experiment, a mid-infrared QCL with emission wavelength near 7.35 μm was used as a laser source. Direct standoff PA detection of trinitrotoluene (TNT) was achieved using an ultrasensitive microphone. The QCL output light was focused on explosive samples in powder form. PA signals were generated and detected directly by an ultrasensitive low-noise microphone with 1 in. diameter. A detection distance up to 8 in. was obtained using the microphone alone. With increasing detection distance, the measured PA signal not only decayed in amplitude but also presented phase delays, which clearly verified the source location. To further increase the detection distance, a parabolic sound reflector was used for effective sound collection. With the help of the sound reflector, standoff PA detection of TNT with distance of 8 ft was demonstrated.

© 2013 Optical Society of America

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References

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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
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2012 (1)

Y. Yao, A. J. Hoffman, and C. F. Gmachl, “Mid-infrared quantum cascade lasers,” Nat. Photonics 6, 432–439 (2012).
[CrossRef]

2011 (1)

2010 (2)

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

A. Mukherjee, S. von der Porten, C. Kumar, and N. Patel, “Standoff detection of explosive substances at distances of up to 150 m,” Appl. Opt. 49, 2072–2078 (2010).
[CrossRef]

2008 (2)

2006 (1)

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

2003 (1)

2001 (1)

2000 (1)

1999 (1)

1994 (1)

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, “Quantum cascade laser,” Science 264, 553–556 (1994).
[CrossRef]

1988 (1)

B. D. van Veen and K. M. Buckley, “Beamforming: a versatile approach to spatial filtering,” IEEE ASSP Mag. 5(2), 4–24 (1988).
[CrossRef]

1986 (1)

A. C. Tam, “Applications of photoacoustic sensing techniques,” Rev. Mod. Phys. 58, 381–431 (1986).
[CrossRef]

1982 (1)

D. J. Brassington, “Photo-acoustic detection and ranging—a new technique for the remote detection of gases,” J. Phys. D 15, 219–228 (1982).
[CrossRef]

1976 (1)

A. Rosencwaig and A. Gersho, “Theory of the photoacoustic effect with solids,” J. Appl. Phys. 47, 64–69 (1976).
[CrossRef]

1881 (1)

Lord Rayleigh, “The photophone,” Nature 23, 274–275(1881).

1880 (2)

W. H. Preece, “On the conversion of radiant energy into sonorous vibrations,” Proc. R. Soc. London 31, 506–520 (1880).
[CrossRef]

A. G. Bell, “On the production and reproduction of sound by light,” Am. J. Sci. 20, 305–324 (1880).

Baillargeon, J. N.

Beck, M.

Bell, A. G.

A. G. Bell, “On the production and reproduction of sound by light,” Am. J. Sci. 20, 305–324 (1880).

Brassington, D. J.

D. J. Brassington, “Photo-acoustic detection and ranging—a new technique for the remote detection of gases,” J. Phys. D 15, 219–228 (1982).
[CrossRef]

Buckley, K. M.

B. D. van Veen and K. M. Buckley, “Beamforming: a versatile approach to spatial filtering,” IEEE ASSP Mag. 5(2), 4–24 (1988).
[CrossRef]

Cannon, J. R.

J. R. Cannon, One-Dimensional Heat Equation, Encyclopedia of Mathematics and its Applications (Addison-Wesley, 1984).

Capasso, F.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, “Quantum cascade laser,” Science 264, 553–556 (1994).
[CrossRef]

Cappasso, F.

Chen, X.

X. Chen, L. Cheng, D. Guo, Y. Kostov, and F.-S. Choa, “Quantum cascade laser based standoff photoacoustic chemical detection,” Opt. Express 19, 20251–20257(2011).
[CrossRef]

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

A. Graninger, X. Chen, and F.-S. Choa, “Stand-off chemical detection using acoustic beam forming and photoacoustic sensing,” presented at the 16th International Congress on Sound and Vibration, Kraków, Poland, 5–9 July 2009.

J. A. Lay, X. Chen, and F. S. Choa, “Performance comparison of microphone and reflector array structures for real-time and outdoor photoacoustic chemical sensing,” submitted to SPIE Defense, Security, and Sensing Conference (SPIE, 2013), paper 8710-12.

Cheng, L.

X. Chen, L. Cheng, D. Guo, Y. Kostov, and F.-S. Choa, “Quantum cascade laser based standoff photoacoustic chemical detection,” Opt. Express 19, 20251–20257(2011).
[CrossRef]

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

Cho, A. Y.

Choa, F. S.

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

J. A. Lay, X. Chen, and F. S. Choa, “Performance comparison of microphone and reflector array structures for real-time and outdoor photoacoustic chemical sensing,” submitted to SPIE Defense, Security, and Sensing Conference (SPIE, 2013), paper 8710-12.

Choa, F.-S.

X. Chen, L. Cheng, D. Guo, Y. Kostov, and F.-S. Choa, “Quantum cascade laser based standoff photoacoustic chemical detection,” Opt. Express 19, 20251–20257(2011).
[CrossRef]

A. Graninger, X. Chen, and F.-S. Choa, “Stand-off chemical detection using acoustic beam forming and photoacoustic sensing,” presented at the 16th International Congress on Sound and Vibration, Kraków, Poland, 5–9 July 2009.

Dunayevskiy, I.

Dunayevskiy, I. G.

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Faist, J.

D. Hofstetter, M. Beck, J. Faist, M. Nägele, and M. W. Sigrist, “Photoacoustic spectroscopy with quantum cascade distributed-feedback lasers,” Opt. Lett. 26, 887–889 (2001).
[CrossRef]

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, “Quantum cascade laser,” Science 264, 553–556 (1994).
[CrossRef]

Fan, J.

Gersho, A.

A. Rosencwaig and A. Gersho, “Theory of the photoacoustic effect with solids,” J. Appl. Phys. 47, 64–69 (1976).
[CrossRef]

Gmachl, C.

Gmachl, C. F.

Y. Yao, A. J. Hoffman, and C. F. Gmachl, “Mid-infrared quantum cascade lasers,” Nat. Photonics 6, 432–439 (2012).
[CrossRef]

Go, R.

A. Mukherjee, I. Dunayevskiy, M. Prasanna, R. Go, A. Tsekoun, X. Wang, J. Fan, C. Kumar, and N. Patel, “Sub-parts-per-billion level detection of dimethyl methyl phosphonate (DMMP) by quantum cascade laser photoacoustic spectroscopy,” Appl. Opt. 47, 1543–1548 (2008).
[CrossRef]

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Graninger, A.

A. Graninger, X. Chen, and F.-S. Choa, “Stand-off chemical detection using acoustic beam forming and photoacoustic sensing,” presented at the 16th International Congress on Sound and Vibration, Kraków, Poland, 5–9 July 2009.

Guo, D.

X. Chen, L. Cheng, D. Guo, Y. Kostov, and F.-S. Choa, “Quantum cascade laser based standoff photoacoustic chemical detection,” Opt. Express 19, 20251–20257(2011).
[CrossRef]

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

Harren, F. J. M.

Harris, M.

Hoffman, A. J.

Y. Yao, A. J. Hoffman, and C. F. Gmachl, “Mid-infrared quantum cascade lasers,” Nat. Photonics 6, 432–439 (2012).
[CrossRef]

Hofstetter, D.

Hutchinson, A. L.

Kostov, Y.

Kumar, C.

Lay, J. A.

J. A. Lay, X. Chen, and F. S. Choa, “Performance comparison of microphone and reflector array structures for real-time and outdoor photoacoustic chemical sensing,” submitted to SPIE Defense, Security, and Sensing Conference (SPIE, 2013), paper 8710-12.

Li, J.-Y.

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

Mukherjee, A.

Nägele, M.

Oomens, J.

Paldus, B. A.

Pao, Y. H.

Y. H. Pao, Optoacoustic Spectroscopy and Detection (Academic, 1977).

Parker, D. H.

Patel, C. K. N.

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Patel, N.

Pearson, G. N.

Perrett, B.

Pierce, A.

A. Pierce, Acoustics (ASA, AIP, 1989).

Pitter, M. C.

Prasanna, M.

Preece, W. H.

W. H. Preece, “On the conversion of radiant energy into sonorous vibrations,” Proc. R. Soc. London 31, 506–520 (1880).
[CrossRef]

Pushkarsky, M.

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Rayleigh, Lord

Lord Rayleigh, “The photophone,” Nature 23, 274–275(1881).

Ridley, K.

Rosencwaig, A.

A. Rosencwaig and A. Gersho, “Theory of the photoacoustic effect with solids,” J. Appl. Phys. 47, 64–69 (1976).
[CrossRef]

A. Rosencwaig, Photoacoustics and Photoacoustic Spectroscopy (Wiley, 1980).

Senesac, L. R.

C. W. Van Neste, L. R. Senesac, and T. Thundat, “Standoff photoacoustic spectroscopy,” Appl. Phys. Lett. 92, 234102 (2008).
[CrossRef]

Sigrist, M. W.

Sirtori, C.

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, “Quantum cascade laser,” Science 264, 553–556 (1994).
[CrossRef]

Sivco, D. L.

Spence, T. G.

Tam, A. C.

A. C. Tam, “Applications of photoacoustic sensing techniques,” Rev. Mod. Phys. 58, 381–431 (1986).
[CrossRef]

Tapster, P. R.

Thundat, T.

C. W. Van Neste, L. R. Senesac, and T. Thundat, “Standoff photoacoustic spectroscopy,” Appl. Phys. Lett. 92, 234102 (2008).
[CrossRef]

Tsekoun, A.

A. Mukherjee, I. Dunayevskiy, M. Prasanna, R. Go, A. Tsekoun, X. Wang, J. Fan, C. Kumar, and N. Patel, “Sub-parts-per-billion level detection of dimethyl methyl phosphonate (DMMP) by quantum cascade laser photoacoustic spectroscopy,” Appl. Opt. 47, 1543–1548 (2008).
[CrossRef]

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Van Neste, C. W.

C. W. Van Neste, L. R. Senesac, and T. Thundat, “Standoff photoacoustic spectroscopy,” Appl. Phys. Lett. 92, 234102 (2008).
[CrossRef]

van Veen, B. D.

B. D. van Veen and K. M. Buckley, “Beamforming: a versatile approach to spatial filtering,” IEEE ASSP Mag. 5(2), 4–24 (1988).
[CrossRef]

von der Porten, S.

Wang, X.

Willetts, D. V.

Worchesky, T.

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

Yao, Y.

Y. Yao, A. J. Hoffman, and C. F. Gmachl, “Mid-infrared quantum cascade lasers,” Nat. Photonics 6, 432–439 (2012).
[CrossRef]

Zare, R. N.

Am. J. Sci. (1)

A. G. Bell, “On the production and reproduction of sound by light,” Am. J. Sci. 20, 305–324 (1880).

Appl. Opt. (4)

Appl. Phys. Lett. (1)

C. W. Van Neste, L. R. Senesac, and T. Thundat, “Standoff photoacoustic spectroscopy,” Appl. Phys. Lett. 92, 234102 (2008).
[CrossRef]

IEEE ASSP Mag. (1)

B. D. van Veen and K. M. Buckley, “Beamforming: a versatile approach to spatial filtering,” IEEE ASSP Mag. 5(2), 4–24 (1988).
[CrossRef]

J. Appl. Phys. (1)

A. Rosencwaig and A. Gersho, “Theory of the photoacoustic effect with solids,” J. Appl. Phys. 47, 64–69 (1976).
[CrossRef]

J. Phys. D (1)

D. J. Brassington, “Photo-acoustic detection and ranging—a new technique for the remote detection of gases,” J. Phys. D 15, 219–228 (1982).
[CrossRef]

Nat. Photonics (1)

Y. Yao, A. J. Hoffman, and C. F. Gmachl, “Mid-infrared quantum cascade lasers,” Nat. Photonics 6, 432–439 (2012).
[CrossRef]

Nature (1)

Lord Rayleigh, “The photophone,” Nature 23, 274–275(1881).

Opt. Express (1)

Opt. Lett. (2)

Proc. Natl. Acad. Sci. USA (1)

M. Pushkarsky, A. Tsekoun, I. G. Dunayevskiy, R. Go, and C. K. N. Patel, “Sub-parts-per-billion level detection of NO2 using room-temperature quantum cascade lasers,” Proc. Natl. Acad. Sci. USA 103, 10846–10849 (2006).
[CrossRef]

Proc. R. Soc. London (1)

W. H. Preece, “On the conversion of radiant energy into sonorous vibrations,” Proc. R. Soc. London 31, 506–520 (1880).
[CrossRef]

Proc. SPIE (1)

X. Chen, L. Cheng, D. Guo, F. S. Choa, T. Worchesky, and J.-Y. Li, “Quasi-continuous-wave operations of quantum cascade lasers,” Proc. SPIE 7750, 775012 (2010).
[CrossRef]

Rev. Mod. Phys. (1)

A. C. Tam, “Applications of photoacoustic sensing techniques,” Rev. Mod. Phys. 58, 381–431 (1986).
[CrossRef]

Science (1)

J. Faist, F. Capasso, D. L. Sivco, C. Sirtori, A. L. Hutchinson, and A. Y. Cho, “Quantum cascade laser,” Science 264, 553–556 (1994).
[CrossRef]

Other (6)

A. Rosencwaig, Photoacoustics and Photoacoustic Spectroscopy (Wiley, 1980).

Y. H. Pao, Optoacoustic Spectroscopy and Detection (Academic, 1977).

A. Graninger, X. Chen, and F.-S. Choa, “Stand-off chemical detection using acoustic beam forming and photoacoustic sensing,” presented at the 16th International Congress on Sound and Vibration, Kraków, Poland, 5–9 July 2009.

A. Pierce, Acoustics (ASA, AIP, 1989).

J. A. Lay, X. Chen, and F. S. Choa, “Performance comparison of microphone and reflector array structures for real-time and outdoor photoacoustic chemical sensing,” submitted to SPIE Defense, Security, and Sensing Conference (SPIE, 2013), paper 8710-12.

J. R. Cannon, One-Dimensional Heat Equation, Encyclopedia of Mathematics and its Applications (Addison-Wesley, 1984).

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Figures (6)

Fig. 1.
Fig. 1.

QCL wavelength spectrum and TNT mid-IR transmission spectrum. Inset shows the QCL power-current relation when operated under quasi-cw condition.

Fig. 2.
Fig. 2.

Experimental setup for pulsed laser induced standoff PA detection of explosive TNT using QCL and ultrasensitive microphone.

Fig. 3.
Fig. 3.

(a) Directly detected PA signal with microphone at 2 in. distance from TNT sample. Yellow trace is the electrical driving pulse voltage, blue trace is the current, and purple trace is the PA signal. (b) PA signal FFT spectrum.

Fig. 4.
Fig. 4.

Measured PA signals with microphone placed at different distances from the TNT sample.

Fig. 5.
Fig. 5.

Relationship of PA signal strength and standoff detection distance; direct microphone measurements in open environment.

Fig. 6.
Fig. 6.

(a) Measured PA signal with microphone placed at 8 ft, with parabolic sound reflector. Yellow trace is the input electrical pulse voltage, green trace is the amplified driving pulse voltage, blue trace is the current, and purple trace is the PA signal. (b) FFT spectrum of the detected PA signal.

Equations (6)

Equations on this page are rendered with MathJax. Learn more.

PA signal = B α E R ,
E abs = E 0 ( 1 e α L ) .
E abs V C p ρ Δ T ,
Δ T = E abs V C p ρ = E 0 ( 1 e α L ) V C p ρ .
Δ T air = const × Δ T .
Δ p = N k B Δ T air = const × N k B E 0 ( 1 e α L ) V C p ρ .

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