ARETE ASSOCIATES — Department of Defense SBIR Phase II: Raman spectroscopy is a highly effective non-contact laser remote sensing method for detec

Description

Raman spectroscopy is a highly effective non-contact laser remote sensing method for detecting and identifying chemicals in every-day field environments. Raman spectroscopy is particularly suited for detecting trace surface contaminants that may indicate the presence of explosives, harmful chemical or biological agents. Contemporary systems, such as the vehicle mounted Joint Contaminated Surface Detector (JCSD), use gaseous KrF excimer lasers operating at 248 nm as the pump laser source. One of the key objections to the KrF laser is the unique maintenance requirements for on-site gas refilling operations that complicate logistics and severely limit that systems reliability. In this SBIR program Arete Associates will develop an efficient, compact, light-weight and rugged diode-pumped solid-state laser alternative. The laser source is based on a frequency quadrupled Q-switched single-frequency Nd:YAG laser operating on the 946 nm transition to achieve the desired 236 nm output. This method is capable of meeting the operating specifications of<45 pm linewidth,>7 mJ pulse energy, 25 Hz pulse repetition rate,>50 ns pulsewidth,<25 lbs,<1800 cu. in and>10,000 hrs operational lifetime. Arete will utilize proprietary single-frequency, injection-seeded, large mode volume resonator designs; advanced composite gain module structures that optimize 946 nm performance; and efficient cascaded frequency doubling in borate crystals to achieve the desired deep UV output wavelength of 236 nm.