Multivariate PEM/FT Spectrometry: Intrinsic Data Fusion And Applications for IED and CB Defense

摘要

We present recent developments in the theory of a new class of active multivariate FT spectrometers and describe their potential uses in the optical detection and identification of improvised explosive devices (IEDs) and CB agents and contaminants. This technology is based on the use of dual ultra- high-speed (UHS) birefringence interferometers for the simultaneous and independent modulation of both illumination and collected beams, and employs photoelastic modulators (PEM) as the birefringent elements in these interferometers. With typical scan rates of 104 105 interferograms per second and broad spectral range, these instruments can rapidly collect multivariate spectral data describing, in a correlated way, the comprehensive excitation, emission, and delay/lifetime spectral properties of the sample/target. The intrinsic process of data fusion that melds the multivariate spectral data into one interferogram signal allows for the simultaneous and correlated use of all three spectral variables for improved discrimination and identification of chemical species of interest.