Laser based Standoff Detection of Explosives: Combination of Complementary Methods

Abstract

Laser based detection systems provide safe and discreet detection and identification of explosives. It is highly suitable for applications like access surveillance at airports or events, monitoring of public events or identification of unknown substances for first responders. They allow direct online measurements from a safe distance to the subject without exposure of personnel or equipment. Raman and Mid-IR absorption spectroscopy yield spectral fingerprints of explosive and hazardous material with concentrations in the range of µg. Comparison with a database by machine learning algorithms results in real-time identification. Since both methods provide complementary spectral information, combined use of both techniques is ideal for a reliable detection and identification. In pursuit of a compact and portable detection system that utilizes deep UV-Raman and Mid-IR absorption, the focus in this presentation was set to the distinction of precursor materials from different backgrounds like textiles. First results for standoff distances below 1 m, both pure and infiltrated in fabric, are promising.