Compressive Imaging FTIR Spectrometer for Chemical and Biological Early Warning

OPTRA proposes the development of a compressive imaging Fourier transform infrared (CI-FTIR) spectrometer capable of resolving the 7 to 14 micron spectral range to 4 cm-1 with a projected noise equivalent spectral radiance of 8.810-8 W/(cm2stercm-1) at an approximately 10 Hz measurement bandwidth. This sensitivity enables detection of a 25 m, 1 ppm Sarin plume with a 2 K temperature contrast relative to the background. Our solution replaces the conventional high cost mercury cadmium telluride (HgCdTe) focal plane array (FPA) with a digital micromirror device and single element HgCdTe detector; the result is an increase in both sensitivity and spectral range owing to the superior radiometric and spectral performance of a single element HgCdTe detector over the FPA at a significantly reduced cost. The CI approach also inherently lends itself to data compression and foveation. Unprecedented spectral acquisition rates are enabled by our high speed resonant FTIR spectrometer coupled with the CI engine. The overall result represents a novel approach to both hyperspectral and compressive imaging realized in a compact sensor package ideal for chemical and biological early warning. The Phase I will produce an analytical model and a conceptual design for a prototype CI-FTIR system.