Electronically Tunable Etalons for Hyperspectral Imaging

We propose to develop high-speed, electronically tunable Fabry-Perot etalon technology for hyperspectral imaging applications. Lightweight reflectors would be piezoelectrically driven fast enough to allow for wavelength selection at camera framing rates.The entire scene would be imaged at a single color with this technology, eliminating the need to process a scene from image cube data, as with grating based imagers.These etalons have unsurpassed throughput, are rugged, and can be made as small as a typical interference filter. We believe they can be retrofitted into existing imagers, possibly in a filter wheel slot. Although they can be applied to any wavelengthregion, they are probably best suited, at least initially, to the infrared, where tolerances are less demanding, and materials do not have to be developed, as with AOTF and liquid crystal etalon technologies. It should be possible to randomly andaccurately select any wavelength in the infrared to an accuracy of about 1%.This research could lead to tunable etalons that could be retrofitted into imagers to add real-time hyperspectral imaging capability. This would be cost effective, and instantaneous imagery is of value in military situations where rapid decisions arerequired. Since no data analysis is needed to reconstruct the images from this technology, it would also add simplicity and and cost reduction to commercial hyperspectral applications.