Photonics, Optics and Lasers

Raman spectroscopy uses lasers to measure molecular vibrations to quickly and accurately identify unknown substances. Ultraviolet (UV) lasers have the optimal wavelength for Raman spectroscopy at stand-off distances, but the Defense Department’s (DoD) current UV-based tactical detection systems are large and expensive and have limited functionality. A new DARPA program seeks technology that may make UV-based detection equipment more readily available in the field.

DARPA yesterday issued a solicitation for proposals responsive to its Spectral Combs from UV to THz (SCOUT) program, which seeks new capabilities for highly sensitive remote detection of multiple biological or chemical agents in liquid or gaseous forms. A proposers day is set for Oct. 15 via webcast.

Spectroscopic chemical sensing, which measures the frequency of light absorbed or scattered from a substance to help determine its molecular identity, can be used to detect traces of biological and chemical agents and residue from explosive materials. Current capabilities in operational military environments, however, lack the sensitivity and broad spectral coverage needed to detect and distinguish among deadly chemicals and the “frequency clutter” generated by common components in the atmosphere.