<title>Progress in AOTF hyperspectral imagers</title>

Acousto-optic tunable filter (AOTF) based imagers hold great promise for the emergence of the next generation of compact, lightweight, low-cost, programmable hyperspectral imaging systems that can solve the problem of data bottleneck as well as provide polarization signatures for better target detection and identification. At the U.S. Army Research Laboratory, we have been developing such imagers that can operate from the visible to the long infrared wavelengths. Some of these imagers have been used in the laboratory and in the field for the collection of hyperspectral images. During the past year, we have worked on the design of higher sensitivity more compact visible and infrared imagers. We have designed imagers with tellurium dioxide (TeO₂) AOTF cells up to 4.5 micrometers and with a thallium arsenic selenide (Tl₃AsSe₃, TAS) AOTF cell up to 11.5 micrometers . These imagers use focal plane arrays (FPAs)--Si CCD, InGaAs, InSb, and HgCdTe--as needed for the spectral region of interest. In this paper, we will describe the latest advances in our AOTF imager research and present the results obtained from these imagers.