Detection of Liquids on Surfaces using Long Wave Infrared Hyperspectral Imaging Spectroradiometer

Not Available "Physical Sciences Inc. proposes to augment AIRIST, its LWIR hyperspectral imaging spectrometer technology, to enable polarization-selected imaging. The resulting spectrometer will enable the detection of surface contamination based on enhancedreflectivity of either s-polarized or p-polarized light. Calculations suggest that surface-deposited persistent liquid chemical warfare agents, such as VX, will exhibit strong differential polarization signatures in the LWIR. Differential polarizationsignatures are expected to be less sensitive to detection scenario, and therefore easier to detect and identify, than surface reflectance spectra recovered from (non-polarized) absolute radiance measurements. (The modified AIRIS will recover absoluteradiance spectra as well as polarization spectra.) Proof-of-concept will be demonstrated in Phase I. A prototype instrument based on the concepts demonstrated in Phase I will be constructed in the Phase II program. The proposed program will lead to asingle sensor for performing sensitive, selective standoff detection of liquid and vapor phase chemical warfare agents (CWAs). In addition to potentially improving its detection sensitivity to CWAs by incorporating polarization-selected detection, AIRIS'simaging and adaptive spectral sampling capability will enable wide areas to surveyed more rapidly than with conventional stand-off sensors, e.g., imaging and non-imaging FTIR and grating spectrometers. In addition to military applications, the proposedsensor will be useful for surface contamination/composition measurements in industrial environments as well as for screening of biological samples (biopsied tissue) for medical applications."