Project Title:

Room Temperature Long Wave Infrared Imaging Spectrometer

Opto-Knowledge Systems, Inc. (OKSI)
1227 Ninth Street
Manhattan Beach, CA 90266-6017

93-1-08     19   6078

Room Temperature Long Wave Infrared Imaging Spectrometer
Investigation

Abstract:

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.

The use of room temperature components in a LWIR imaging
spectrometer present the opportunity to develop instruments that
are smaller, lighter, more reliable, more portable, and less
expensive. There is a growing need for such systems in spaceborne
missions for planetary applications or earth remote sensing,
ground environmental monitoring, low enforcement and forensics,
night vision and target recognition systems.

LVF, LWIR, Imaging-Spectroscopy, Uncooled-Optics, Narcissus