Stand-off detection of explosives particles by multispectral imaging Raman spectroscopy
2011 (English)In: Applied Optics, ISSN 0003-6935, E-ISSN 1539-4522, Vol. 50, no 28, 5592-5599 p.Article in journal (Refereed) Published
A Raman multispectral imaging technique is presented, which can be used for stand-off detection of single explosives particles. A frequency-doubled Nd:YAG laser operating at 10 Hz illuminates the surface under investigation. The backscattered Raman signal is collected by a receiver subsystem consisting of a 150 mm Schmidt-Cassegrain telescope, a laser line edge filter, a liquid-crystal tunable filter, and a gated intensified charge-coupled device (ICCD) detector. A sequence of images is recorded by the ICCD, where, for each recording, a different wavelength is selected by the tunable filter. By this, a Raman spectrum is recorded for each pixel, which makes it possible to detect even single particles when compared to known spectra for possible explosives. The comparison is made using correlation and least-square fitting. The system is relatively insensitive to environment and light variations. Multispectral Raman images of sulfur, ammonium nitrate, 2,4-dinitrotoluene, and 2,4,6-trinitrotoluene were acquired at a stand-off distance of 10 m. Detection of sulfur particles was done at a distance of 10 m.
Place, publisher, year, edition, pages
2011. Vol. 50, no 28, 5592-5599 p.
UV, ENVIRONMENT, RESIDUES, SYSTEMS, RDX
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:kth:diva-47989DOI: 10.1364/AO.50.005592ISI: 000295842600050ScopusID: 2-s2.0-80053404678OAI: oai:DiVA.org:kth-47989DiVA: diva2:456904
QC 201111162011-11-162011-11-152011-11-16Bibliographically approved