Infrared Acousto-Optic Tunable Filter

The acousto-optic tunable filter (AOTF) is an electronically tunable optical filter that has a large angular aperture while maintaining high spectral resolution. Combined with the ability of simultaneous polarization measurement, and the advantage of small size and weight, the AOTF is well-suited to remote sensing applications. Current AOTF technology has major performance deficiencies that limit its potential for infrared spectral regions. It is the objective of this program to overcome these deficiencies and significantly advance the AOTF technology for practical deployment in infrared imaging systems. A risk reduction effort is proposed in Phase I. The proposed task includes: (a) Design, build and test a resonant infrared TeO2 AOTF to demonstrate low drive power. (b) Operate and evaluate TeO2 AOTF at cryogenic temperatures. (c) Investigate material issues, design concepts and fabrication techniques for wide range infrared AOTFs beyond 5 micrometers.