*** 9801531 Lieberman This Small Business Innovation Research (SBIR) Phase II project will use a new approach to correlation spectroscopy to develop a rugged, cost-effective, highly sensitive, chemical detection system. Using a novel tunable filter demonstrated during Phase I to replace the unwieldy "reference cell" found in current systems, a compact sensor package will be fabricated that allows this powerful technique to be used in a wide variety of field applications. The heart of the system is an optical structure whose transmission spectrum has been radically altered to match the target compound by incorporating a series of light-scattering elements; the filter is modulated to tune its spectrum into and out of coincidence with that of the target, providing highly compound-specific detection. The Phase II project will: (1) Mathematically model the new sensor, (2) Optimize the filter and modulation system, (3) Optimize the semiconductor light source used in the system, (4) Increase spectral modulation frequencies, (5) Integrate all components into a complete correlation spectroscopy system and demonstrate response suitable for commercial methane sensing, and (6) Initiate plans and strategic relations that will lead to Phase III commercialization of sensors based on this new technology. The Phase II system will lead directly to a practical methane sensor that can be used in mine monitoring, and potentially even in home safety applications. By simply replacing the tunable tailored filter element, the same basic optoelectronic unit can be used to sense other hydrocarbon gases, different greenhouse gases, or other compounds. Spin-off applications for tunable tailored filters also abound in other branches of photonics. ***
