Laser based explosives detection

Abstract

Transport Canada (TC) and the Federal Aviation Administration (FAA) have been active players in the research and development of trace explosive detection systems (TEDS). Under the direction of TC, private industry has been asked to develop devices meeting more and more stringent criteria. The recent development of a specification for TEDS by TC will provide industry with a clear blueprint for developing devices which will serve the traveling public today and into the foreseeable future. One of the ongoing projects involves the use of laser-based explosives detection. This technique involves the use of laser-generated infrared radiation to scan the surface of objects. The interaction of the laser radiation with any residual explosive on the surface of the object will initiate 'micro' bursts. The resulting light generated by these bursts can be detected and is characteristic of the explosive involved. Temporal and spectral analyses of the emitted light reveal unique signal pattems that are used to differentiate the 'micro' bursts. The results are preliminary, however, the technique offers the potential for detecting explosives on objects in near-real time. Thus, the technique could be used to scan carry-on baggage as the individual pieces of luggage travel on the x-ray system's conveyer belt.

Single Broadband Phase-Shaped Pulse Stimulated Raman Spectroscopy for Standoff Trace Explosive Detection

“…Bulk detection can be further divided into two approaches: the use of a swab to collect residues that can be analyzed by standard analytical approaches and the use of lasers to detect residues at a distance . Here, we focus on using lasers at distances greater than 1 m to detect explosives on a variety of surfaces ranging from car panels to clothing.…”

“…Bulk detection can be further divided into two approaches: the use of a swab to collect residues that can be analyzed by standard analytical approaches 16 and the use of lasers to detect residues at a distance. 17 Here, we focus on using lasers at distances greater than 1 m to detect explosives on a variety of surfaces ranging from car panels to clothing. We will not discuss approaches based on laserinduced fluorescence 18 because fluorescence from explosives or their photofragments is weak and broad, preventing sensitivity and selectivity.…”