Room-Temperature, Long-Wave Infrared Spectrometer

If uncooled to cryogenic temperature, the opto-mechanical components in a long wave infrared imaging spectrometer emit broadband thermal radiation that at best may reduce the dynamic range of the Focal Plane Array, or completely saturate it. One solution is to mount a Linear Variable Filter over the FPA and block most of the thermal clutter from reaching the FPA. However, mounting the LVF over the FPA in perfect alignment with the rows of pixel is not easy. The direct deposition of the LVF coatings onto the FPA can simplify the preocess and produce a permanently aligned FPA that can operate with room temperature opto-mechanical systems. The technological issues associated with the process of depositing a wedge shaped interference filter over an IRFPA, and an alternative approach based on the Narcissus Effect will be investigated during the Phase I contract. A demonstration of the concept with prototype hardware is contemplated for Phase II. We propose to perform the demonstration by installing the new FPA in one of JPL's sensors, the Thermal Infrared Imaging Spectrometer. Successful development of the technology will directly support NASA's planetary and remote earth observation activities.