Polarimetric lidar signatures for remote detection of biological warfare agents

Polarimetric Lidar has been recently proposed as a method for remote detection of aerosolized biological warfare agents. Accurate characterization of the optical signatures for both biological agents and environmental interferents is a critical first step toward successful sensor deployment. MIT Lincoln Laboratory has developed the Standoff Aerosol Active Signature Testbed (SAAST) as a tool for characterizing aerosol elastic scattering cross sections.1 The spectral coverage of the SAAST includes both the nearinfrared (1-1.6 μm) and mid-infrared (3-4 μm) spectral regions. The SAAST source optics are capable of generating all six classic optical polarization states, while the polarization-sensitive receiver is able to reconstruct the full Stokes vector of the scattered wave. All scattering angles, including those near direct backscatter, can be investigated. The SAAST also includes an aerosol generation system capable of producing biological and inert samples with various size distributions. This paper discusses the underlying scattering phenomenology, SAAST design details, and presents some representative data.

[1]  Pierre Mathieu,et al.  Bioaerosols laser-induced fluorescence provides specific robust signatures for standoff detection , 2006, SPIE Optics East.

[2]  Terrance J Leighton,et al.  The high-resolution architecture and structural dynamics of Bacillus spores. , 2004, Biophysical journal.

[3]  Hsiao-hua K. Burke,et al.  Polarimetric bio-aerosol detection: numerical simulation , 2005, SPIE Optics East.

[4]  George M. Dougherty,et al.  Field-capable biodetection devices for homeland security missions , 2007, SPIE Defense + Commercial Sensing.

[5]  Shane D. Mayor,et al.  Polarization lidar at 1.54 m and observations of plumes from aerosol generators , 2007 .

[6]  Larry D. Travis,et al.  Light scattering by nonspherical particles : theory, measurements, and applications , 1998 .

[7]  J. W. Snow,et al.  Standoff Polarimetric Aerosol Detection (SPADE) for Biodefense , 2005 .

[8]  M. Milham,et al.  Optical properties of Bacillus subtilis spores from 0.2 to 2.5 num. , 1997, Applied optics.

[9]  W. Steen Absorption and Scattering of Light by Small Particles , 1999 .

[10]  S. Pal,et al.  Polarization properties of lidar backscattering from clouds. , 1973, Applied optics.

[11]  K. Gurton,et al.  Measured Infrared Spectral Extinction for Aerosolized Bacillus subtilis var. niger Endospores from 3 to 13 mum. , 2001, Applied optics.

[12]  G. Roy,et al.  Remote biodetection performance of a pulsed monostatic lidar system. , 1992, Applied optics.

[13]  M. Mishchenko,et al.  Reprint of: T-matrix computations of light scattering by nonspherical particles: a review , 1996 .

[14]  Antonio Diaz,et al.  Systems engineering tradeoffs for a bio-aerosol lidar referee system , 2004, SPIE Defense + Commercial Sensing.

[15]  Andrew A. Lacis,et al.  Scattering, Absorption, and Emission of Light by Small Particles , 2002 .

[16]  John C. Aldridge,et al.  THE STANDOFF AEROSOL ACTIVE SIGNATURE TESTBED (SAAST) AT MIT LINCOLN LABORATORY , 2008 .

[17]  Michael E. Thomas,et al.  Determination of bacterial aerosol spectral cross sections , 2004, SPIE Defense + Commercial Sensing.

[18]  C. Tropea,et al.  Light Scattering from Small Particles , 2003 .

[19]  K. R. May The collison nebulizer: Description, performance and application , 1973 .