Abstract

We measure the diffuse reflection spectrum of solid samples such as explosives (TNT, RDX, PETN), fertilizers (ammonium nitrate, urea), and paints (automotive and military grade) at a stand-off distance of 5 m using a mid-infrared supercontinuum light source with 3.9 W average output power. The output spectrum extends from 750–4300 nm, and it is generated by nonlinear spectral broadening in a 9 m long fluoride fiber pumped by high peak power pulses from a dual-stage erbium-ytterbium fiber amplifier operating at 1543 nm. The samples are distinguished using unique spectral signatures that are attributed to the molecular vibrations of the constituents. Signal-to-noise ratio (SNR) calculations demonstrate the feasibility of increasing the stand-off distance from 5 to 150m, with a corresponding drop in SNR from 28 to 10 dB.

© 2012 Optical Society of America

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2011 (2)

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

2010 (1)

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

2009 (7)

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

A. J. Hobro, B. Lendl, “Stand-off Raman spectroscopy,” Trends Anal. Chem. 28, 1235–1242 (2009).
[CrossRef]

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

H. Li, D. A. Harris, B. Xu, P. J. Wrzesinski, V. V. Lozovoy, M. Dantus, “Standoff and arms-length detection of chemicals with single-beam coherent anti-Stokes Raman scattering,” Appl. Opt. 48, B17–B22 (2009).
[CrossRef]

2008 (4)

2006 (3)

2005 (1)

2003 (1)

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

2001 (1)

M. Leona, J. Winter, “Fiber optics reflectance spectroscopy: a unique tool for the investigation of Japanese paintings,” Studies Conser. 46, 153–162 (2001).
[CrossRef]

1999 (1)

1997 (2)

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

F. V. D. Meer, W. Bakker, “CCSM: cross correlogram spectral matching,” Int. J. Remote Sensing 18, 1197–1201 (1997).
[CrossRef]

1995 (2)

1990 (1)

T. H. Demetriades-Shah, M. D. Steven, J. A. Clark, “High resolution derivatives spectra in remote sensing,” Remote Sens. Environ. 33, 55–64, 1990.
[CrossRef]

1978 (1)

M. P. Fuller, P. R. Griffiths, “Diffuse reflectance measurements by infrared Fourier transform spectroscopy,” Anal. Chem. 50, 1906–1910 (1978).
[CrossRef]

1964 (1)

A. Savitzky, M. J. E. Golay, “Smoothing and differentiation of data by simplified least squares procedures,” Anal. Chem. 36, 1627–1639 (1964).
[CrossRef]

1957 (1)

J. E. Stewart, “Infrared absorption spectra of urea, thiourea, and some thiourea‐alkali halide complexes,” J. Chem. Phys. 26, 248–255 (1957).
[CrossRef]

Aggarwal, I.

I. Schneider, G. Nau, T. V. V. King, I. Aggarwal, “Fiber optic near-infrared reflectance sensor for detection of organics in soils,” IEEE Photon. Technol. Lett. 7, 87–89 (1995).
[CrossRef]

Aleksoff, C.

Alexander, V. V.

Allen, M. G.

Anbalagan, G.

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

Angel, S. M.

Averett, L. A.

Bahou, M.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Bakker, W.

F. V. D. Meer, W. Bakker, “CCSM: cross correlogram spectral matching,” Int. J. Remote Sensing 18, 1197–1201 (1997).
[CrossRef]

Banas, A.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Banas, K.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Blake, T. A.

Canal, C. M.

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

Carleton, K. L.

Carter, J. C.

Chaudhari, C.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Chiantore, O.

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

Cholewa, M.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Clark, J. A.

T. H. Demetriades-Shah, M. D. Steven, J. A. Clark, “High resolution derivatives spectra in remote sensing,” Remote Sens. Environ. 33, 55–64, 1990.
[CrossRef]

Comanescu, G.

Cushing, M. C.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Daniel, R. G.

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

Dantus, M.

Davidson, D.

Davis, S. J.

Demetriades-Shah, T. H.

T. H. Demetriades-Shah, M. D. Steven, J. A. Clark, “High resolution derivatives spectra in remote sensing,” Remote Sens. Environ. 33, 55–64, 1990.
[CrossRef]

Denault, A. J.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Escarsega, J. A.

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

Field, R. W.

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

Freeman, M. J.

Fuller, M. P.

M. P. Fuller, P. R. Griffiths, “Diffuse reflectance measurements by infrared Fourier transform spectroscopy,” Anal. Chem. 50, 1906–1910 (1978).
[CrossRef]

Furstenberg, R.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Gallagher, N. B.

Gassman, P. L.

Gilbert, B. D.

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

Golay, M. J. E.

A. Savitzky, M. J. E. Golay, “Smoothing and differentiation of data by simplified least squares procedures,” Anal. Chem. 36, 1627–1639 (1964).
[CrossRef]

Gottfried, J. L.

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

Green, R. J.

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

Griffiths, P. R.

Grun, J.

Gunasekaran, S.

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

Gupta, S. C.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Harris, D. A.

Hobro, A.

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

Hobro, A. J.

A. J. Hobro, B. Lendl, “Stand-off Raman spectroscopy,” Trends Anal. Chem. 28, 1235–1242 (2009).
[CrossRef]

Hutchins, D. A.

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

Ingale, S. V.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Islam, M. N.

Janni, J.

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

Kaste, P. J.

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

Kendziora, C.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Kessler, W. J.

King, T. V. V.

I. Schneider, G. Nau, T. V. V. King, I. Aggarwal, “Fiber optic near-infrared reflectance sensor for detection of organics in soils,” IEEE Photon. Technol. Lett. 7, 87–89 (1995).
[CrossRef]

Kito, C.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Klooster, A.

Kulkarni, O. P.

Kumar, M.

Lawrence-Snyder, M.

Lendl, B.

A. J. Hobro, B. Lendl, “Stand-off Raman spectroscopy,” Trends Anal. Chem. 28, 1235–1242 (2009).
[CrossRef]

Leona, M.

M. Leona, J. Winter, “Fiber optics reflectance spectroscopy: a unique tool for the investigation of Japanese paintings,” Studies Conser. 46, 153–162 (2001).
[CrossRef]

Li, H.

Li, Z. J.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Liao, M.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Lim, Ch. H.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Lim, S. K.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Lozovoy, V. V.

Lucia, F. C. D.

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

Ma, X.

Manka, C. K.

Mannoun, O. M.

B. I. Vasil’ev, O. M. Mannoun, “IR differential-absorption LIDARs for ecological monitoring of the environment,” Quantum Electron. 36, 801–820 (2006).
[CrossRef]

Mazé, G.

McGill, R. A.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Meer, F. V. D.

F. V. D. Meer, W. Bakker, “CCSM: cross correlogram spectral matching,” Int. J. Remote Sensing 18, 1197–1201 (1997).
[CrossRef]

Miziolek, A. W.

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

Moser, H. O.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Mukundakumari, S.

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

Munson, C. A.

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

Murugesan, K. S.

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

Nau, G.

I. Schneider, G. Nau, T. V. V. King, I. Aggarwal, “Fiber optic near-infrared reflectance sensor for detection of organics in soils,” IEEE Photon. Technol. Lett. 7, 87–89 (1995).
[CrossRef]

Nervo, M.

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

Nguyen, V.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Nikitin, S.

Ohishi, Y.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Onaka, P. M.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Ostmark, H.

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

Otis, C. E.

Palombo, D. A.

Papantonakis, M.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Patra, A. K.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Pesce-Rodriguez, R. A.

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

Pettersson, A.

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

Piccirillo, A.

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

Poli, T.

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

Poulain, M.

Qin, G.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Rake, M.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Rayner, J. T.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Reynolds, J. G.

Saleem, A.

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

Sastry, P. U.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Sausa, R. C.

Savitzky, A.

A. Savitzky, M. J. E. Golay, “Smoothing and differentiation of data by simplified least squares procedures,” Anal. Chem. 36, 1627–1639 (1964).
[CrossRef]

Scaffidi, J.

Schneider, I.

I. Schneider, G. Nau, T. V. V. King, I. Aggarwal, “Fiber optic near-infrared reflectance sensor for detection of organics in soils,” IEEE Photon. Technol. Lett. 7, 87–89 (1995).
[CrossRef]

Schroeder, M. A.

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

Shaver, J. M.

Singh, G.

Sonnenfroh, D. M.

Stahlberger, W. E.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Steinfeld, J. I.

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

Stepnowski, J.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Stepnowski, S. V.

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Steven, M. D.

T. H. Demetriades-Shah, M. D. Steven, J. A. Clark, “High resolution derivatives spectra in remote sensing,” Remote Sens. Environ. 33, 55–64, 1990.
[CrossRef]

Stewart, J. E.

J. E. Stewart, “Infrared absorption spectra of urea, thiourea, and some thiourea‐alkali halide complexes,” J. Chem. Phys. 26, 248–255 (1957).
[CrossRef]

Suzuki, T.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Swayambunathan, V.

Terry, F. L.

Tewari, R.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Toomey, D. W.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Vacca, W. D.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Vasil’ev, B. I.

B. I. Vasil’ev, O. M. Mannoun, “IR differential-absorption LIDARs for ecological monitoring of the environment,” Quantum Electron. 36, 801–820 (2006).
[CrossRef]

Wagh, P. B.

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Wallin, S.

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

Wang, S.

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Wen, L.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Whipple, R. E.

Windig, W.

Winter, J.

M. Leona, J. Winter, “Fiber optics reflectance spectroscopy: a unique tool for the investigation of Japanese paintings,” Studies Conser. 46, 153–162 (2001).
[CrossRef]

Wrzesinski, P. J.

Xia, C.

Xu, B.

Yan, X.

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

Yang, P.

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Zabetakis, D.

Anal. Bioanal. Chem. (2)

T. Poli, O. Chiantore, M. Nervo, A. Piccirillo, “Mid-IR fiber-optic reflectance spectroscopy for identifying the finish on wooden furniture,” Anal. Bioanal. Chem. 400, 1161–1171 (2011).
[CrossRef]

S. Wallin, A. Pettersson, H. Ostmark, A. Hobro, “Laser based standoff detection of explosives: a critical review,” Anal. Bioanal. Chem. 395, 259–274 (2009).
[CrossRef]

Anal. Bionanal. Chem. (1)

J. L. Gottfried, F. C. D. Lucia, C. A. Munson, A. W. Miziolek, “Laser induced breakdown spectroscopy for detection of explosives residues: a review of recent advances, challenges and future prospects,” Anal. Bionanal. Chem. 395, 283–300 (2009).
[CrossRef]

Anal. Chem. (2)

M. P. Fuller, P. R. Griffiths, “Diffuse reflectance measurements by infrared Fourier transform spectroscopy,” Anal. Chem. 50, 1906–1910 (1978).
[CrossRef]

A. Savitzky, M. J. E. Golay, “Smoothing and differentiation of data by simplified least squares procedures,” Anal. Chem. 36, 1627–1639 (1964).
[CrossRef]

Anal. Meth. (1)

C. M. Canal, A. Saleem, R. J. Green, D. A. Hutchins, “Remote identification of chemicals concealed behind clothing using near infrared spectroscopy,” Anal. Meth. 3, 84–91 (2011).
[CrossRef]

Appl. Opt. (3)

Appl. Phys. Lett. (2)

G. Qin, X. Yan, C. Kito, M. Liao, C. Chaudhari, T. Suzuki, Y. Ohishi, “Ultrabroadband supercontinuum generation from ultraviolet to 6.28 μm in a fluoride fiber,” Appl. Phys. Lett. 95, 161103 (2009).
[CrossRef]

R. Furstenberg, C. Kendziora, M. Papantonakis, S. V. Stepnowski, J. Stepnowski, V. Nguyen, M. Rake, R. A. McGill, “Stand-off detection of trace explosives via resonant infrared photothermal imaging,” Appl. Phys. Lett. 93, 224103(2008).
[CrossRef]

Appl. Spectrosc. (4)

IEEE Photon. Technol. Lett. (1)

I. Schneider, G. Nau, T. V. V. King, I. Aggarwal, “Fiber optic near-infrared reflectance sensor for detection of organics in soils,” IEEE Photon. Technol. Lett. 7, 87–89 (1995).
[CrossRef]

Int. J. Remote Sensing (1)

F. V. D. Meer, W. Bakker, “CCSM: cross correlogram spectral matching,” Int. J. Remote Sensing 18, 1197–1201 (1997).
[CrossRef]

J. Chem. Phys. (1)

J. E. Stewart, “Infrared absorption spectra of urea, thiourea, and some thiourea‐alkali halide complexes,” J. Chem. Phys. 26, 248–255 (1957).
[CrossRef]

J. Sol-Gel Sci. Technol. (1)

S. V. Ingale, P. U. Sastry, A. K. Patra, R. Tewari, P. B. Wagh, S. C. Gupta, “Micro structural investigations of TNT and PETN incorporated silica xerogels,” J. Sol-Gel Sci. Technol. 54, 238–242 (2010).
[CrossRef]

Opt. Express (1)

Opt. Lett. (1)

Publ. Astron. Soc. Pac. (1)

J. T. Rayner, D. W. Toomey, P. M. Onaka, A. J. Denault, W. E. Stahlberger, W. D. Vacca, M. C. Cushing, S. Wang, “A medium-resolution 0.8–5.5 micron spectrograph and imager for the NASA Infrared Telescope Facility,” Publ. Astron. Soc. Pac. 115, 362–382 (2003).
[CrossRef]

Quantum Electron. (1)

B. I. Vasil’ev, O. M. Mannoun, “IR differential-absorption LIDARs for ecological monitoring of the environment,” Quantum Electron. 36, 801–820 (2006).
[CrossRef]

Remote Sens. Environ. (1)

T. H. Demetriades-Shah, M. D. Steven, J. A. Clark, “High resolution derivatives spectra in remote sensing,” Remote Sens. Environ. 33, 55–64, 1990.
[CrossRef]

Spectrochim. Acta Part A (1)

J. Janni, B. D. Gilbert, R. W. Field, J. I. Steinfeld, “Infrared absorption of explosive molecule vapors,” Spectrochim. Acta Part A 53, 1375–1381 (1997).
[CrossRef]

Studies Conser. (1)

M. Leona, J. Winter, “Fiber optics reflectance spectroscopy: a unique tool for the investigation of Japanese paintings,” Studies Conser. 46, 153–162 (2001).
[CrossRef]

Trends Anal. Chem. (1)

A. J. Hobro, B. Lendl, “Stand-off Raman spectroscopy,” Trends Anal. Chem. 28, 1235–1242 (2009).
[CrossRef]

Vibrat. Spectrosc. (2)

G. Anbalagan, S. Mukundakumari, K. S. Murugesan, S. Gunasekaran, “Infrared, optical absorption, and EPR spectroscopc studies on natural gypsum,” Vibrat. Spectrosc. 50, 226–230 (2009).
[CrossRef]

A. Banas, K. Banas, M. Bahou, H. O. Moser, L. Wen, P. Yang, Z. J. Li, M. Cholewa, S. K. Lim, Ch. H. Lim, “Post-blast detection of traces of explosives by means of Fourier transform infrared spectroscopy,” Vibrat. Spectrosc. 51, 168–176 (2009).
[CrossRef]

Other (2)

Lawrence Berkeley National Laboratory Pigment Database—Cobalt Chromite Green Spinel, http://coolcolors.lbl.gov/LBNL-Pigment-Database/paints/G05.html .

P. J. Kaste, R. G. Daniel, R. A. Pesce-Rodriguez, M. A. Schroeder, J. A. Escarsega, “Hydrogen plasma removal of military paints: chemical characterization of samples,” Report no. A128453, Army Research Laboratory, Aberdeen Proving Ground, 1998.

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Figures (13)

Fig. 1.
Fig. 1.

Experimental setup for SC-based stand-off diffuse reflection spectroscopy. Collimated light from the SC source is incident normally on the sample 5 m away, and diffusely reflected light at a reflection angle of 2.3° is collected by a concave mirror. Low noise detection of the signal is achieved with a lock-in amplifier connected to a liquid-nitrogen-cooled InSb detector at the monochromator output.

Fig. 2.
Fig. 2.

Experimental setup for mid-IR SC generation in ZBLAN fiber. Light from a 1543 nm telecom laser diode is amplified to 19 kW peak power in two stages of cladding pumped erbium-ytterbium fiber amplifiers. The output is mechanically coupled into an 8 μm core diameter and 9 m long ZBLAN fiber to produce a broadband SC spectrum.

Fig. 3.
Fig. 3.

SC output from 9 m ZBLAN fiber: spectrum spanning 750–4300 nm with 3.9 W average output power. Output has > 1 mW / nm ( 0 dBm / nm ) spectral power density in the wavelength range from 2000 to 4200 nm. The broad SC is generated by a mixture of nonlinear effects such as modulation instability and stimulated Raman scattering.

Fig. 4.
Fig. 4.

Power scalability of SC output power. The plot shows a linear increase in SC average output power with the seed laser pulse repetition rate. The corresponding 976 nm pump power used in the power amp stage is listed next to the data points. The SC was operated at the highest repetition rate of 2 MHz for all the sample measurements.

Fig. 5.
Fig. 5.

Chemical structure and formula of NESTT samples—TNT, RDX, PETN, potassium nitrate. TNT belongs to the nitroaromatics class, RDX to nitramines, and PETN to nitrate esters. The fundamental and overtone vibrations of different functional groups are responsible for the unique spectral features observed in each sample.

Fig. 6.
Fig. 6.

Absorbance spectra of NESTT sample set #1—TNT, RDX, PETN, potassium nitrate. The strongest absorption features in TNT, RDX, and PETN are in the 3200–2500 nm band and arise due to the fundamental aromatic and aliphatic C–H stretch. The spectral features around 3600 nm in potassium nitrate arise due to the first overtone of the N–O asymmetric stretch. The common broad feature at 2720 nm in all four samples is due to the O–H stretch from absorbed water in the fused silica host.

Fig. 7.
Fig. 7.

Reflection spectra of sample set #2—gypsym, pine wood, ammonium nitrate, urea. The main spectral features in gypsum arise due to fundamental and combination bands of water. The pine wood spectrum has absorption features from C–H, O–H, and C–O stretches attributed to cellulose, lignin, and water. The N–H stretch and N–H bending vibrations are responsible for absorption dips in ammonium nitrate, while the C–O stretch produces absorption features in urea.

Fig. 8.
Fig. 8.

Reflection spectra of sample set #3—automotive and military CARC paints. The strong absorption from 3200 to 3500 nm in all paints is due to the C–H stretch, while that from 2850 to 3150 nm in the auto-red and auto-green is due to the N–H stretch from the acrylic-melamine base. The unique feature of the CARC-green paint is a broad absorption between 1200 and 1850 nm due to the green pigment Cobalt Chromite.

Fig. 9.
Fig. 9.

Variation of SC output at 4000 nm over 300 s. With the signal normalized to a mean of 100%, we obtain a standard deviation of 0.16%. The standard deviation remains unchanged even when the signal is attenuated by 10 dB. Thus, the SC fluctuations can always be expressed as a fixed root-mean-square percentage of the mean SC output, regardless of the absolute signal level.

Fig. 10.
Fig. 10.

Comparison of urea reflection spectrum obtained using the SC-based setup with that obtained using an FTIR with a diffuse reflection accessory. There is good agreement in the shape and peak positions of the two spectra. The difference in absolute scale between the two plots is attributed to the difference in reflection measurement geometries of the two setups.

Fig. 11.
Fig. 11.

Flow chart describing the algorithm to demonstrate selectivity between two samples. The algorithm uses the correlation coefficient in selected spectral bands to quantify the degree of similarity or dissimilarity between two reflection spectra. If the mean correlation coefficient over the selected bands > 0.9 , the two samples are said to be a match.

Fig. 12.
Fig. 12.

Variation in predicted system SNR versus sample stand-off distance. At small distances < 10 m , the noise is dominated by the SC fluctuations and the SNR is independent of distance. At large distances > 20 m , the detector noise term is dominant and SNR is inversely proportional to the square of the sample distance.

Fig. 13.
Fig. 13.

Definition of absorption band depth. R a is the reflectance value at the bottom of an absorption dip, while R b is the reflectance value outside it.

Tables (5)

Tables Icon

Table 1. Supercontinuum Output Power in Different Spectral Regions a

Tables Icon

Table 2. Correlation Table for Sample Set #1: NESTT—TNT, RDX, PETN, and Potassium Nitrate

Tables Icon

Table 3. Correlation Table for Sample Set #2: Ammonium Nitrate, Urea, Gypsum, and Pine Wood

Tables Icon

Table 4. Correlation Table for Sample Set #3: Military CARC-Green and Automotive Black, Red, and Green Paints

Tables Icon

Table 5. Comparison of Spectroscopic Optical Stand-Off Detection Techniques (Adapted from Wallin et al. [7]) a

Equations (7)

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

r = i = 1 n ( X i X ¯ ) ( Y i Y ¯ ) i = 1 n ( X i X ¯ ) 2 i = 1 n ( Y i Y ¯ ) 2 .
V signal = P SC × R m 1 × T c h × R m 2 × R s × ( π / d 2 ) × ( π r 2 ) × Δ λ × η × D × G = 0.096 / d 2 .
InSb detector dark current , I det = 36 μA ( manufacturer spec ) Detector dark current shot noise current density , I det = ( 2 e I det ) 1 / 2 pA / Hz 1 / 2 Detector dark current shot noise voltage density , e det = i det × G = 363 nV / Hz 1 / 2
SC noise density , e SC = 0.0016 * V signal nV / Hz 1 / 2 ( from Subsection 3.D )
Lock-in amplifier noise , e lia = 7 nV / Hz 1 / 2 ( manufacturer spec ) Detector preamp noise , e pa = 20 nV / Hz 1 / 2 ( manufacturer spec ) Total noise floor density , e tot = ( e det 2 + e SC 2 + e lia 2 + e SC 2 ) ( e det 2 + e SC 2 ) 1 / 2
Lock-in detection bandwidth , B = 1 Hz Total noise floor , V noise = e tot × B 1 / 2
SNR ( linear ) = V signal / V noise SNR ( dB ) = 10 × log ( V signal / V noise ) .

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