Tunable Spectral Sifting (TSS) Filter for Space Sensors

Optical Physics Company (OPC) is proposing to investigate a novel tunable spectral sifting (TSS) filter design to enhance the capabilities of space sensors for the STSS and AIRSS programs. TSS filter design goals are tailored for these two space-based sensor acquisition programs, to select between two tunable passbands, with sub-passband selectivity, at the water vapor absorption band and the carbon dioxide absorption band, with passband transmittance in excess of 90% and radiation hardened to 300krad. Subcontractor Raytheon SAS will assist OPC in defining rad-hard optical filter optical components, focal plane array, algorithms, and processor for a flight testable design, and in defining the TSS demo unit proposed for Phase II. Phase I work involves detailed specifications of the TSS filter in two configurations, to accommodate different fields of view associated with low and geosynchronous Earth orbits of the satellites. The design effort will be followed by evaluation of system trade-offs, building and testing of one stage of the TSS filter, and formulation of a Phase II prototype design and test plan.