1. To: SD102, Descour/Shen 2. Conference: Imaging Spectrometry V (SD102) 3. Title: MTI Focal Plane Assembly Design and Performance 4. Authors: Jeffrey Rienstra Sandia National Laboratories P.O. Box 5800, M/S 0972 Albuquerque, NM 87185-0972 Tel. 505-845-8682, Fax 505-844-0906 jlriens@sandia.gov Mary Ballard Raytheon Infrared Center of Excellence 75 Coromar Dr., Bldg B3, M/S 85 Goleta, CA 93117 Tel. 805-562-2729, Fax 805-562-4510 mballard@west.raytheon.com 5. Presentation preference: Oral 6. Abstract: The focal plane assembly for the Multispectral Thermal Imager (MTI) consists of sensor chip assemblies, optical filters, and a vacuum enclosure. Sensor chip assemblies, composed of linear detector arrays and readout integrated circuits, provide spatial resolution in the cross-track direction for the pushbroom imager. Optical filters define 15 spectral bands in a range from 0.45 mmm to 10.7 mmm. All the detector arrays are mounted on a single focal plane and are designed to operate at 75 K. The four spectral bands covering the visible to near infrared wavelength range have roughly 2400 pixels each, and the remaining 11 spectral bands have roughly 600 pixels each. Three pairs of sensor chip assemblies (SCAs) are required to provide cross-track coverage in all 15 spectral bands. Each pair of SCAs includes detector arrays made from silicon, indium antimonide, and mercury cadmium telluride. Readout integrated circuits multiplex the signals from the detectors to 18 separate video channels. Optical filter assemblies defining the spectral bands are mounted over the linear detector arrays Each filter assembly consists of several filter strips bonded together side-by-side. The vacuum enclosure provides mechanical support for the SCAs and filter assemblies, cold shielding, and a means for testing the unit in the laboratory at operating temperature. The MTI focal plane assembly has been integrated with the rest of the payload and tested. The payload is currently undergoing detailed calibration. This paper includes representative test data for the various spectral bands and the overall performance of the focal plane assembly. 7. Keywords: Multispectral imaging, focal plane arrays, remote sensing 8. Biographies: Jeffrey Rienstra obtained a B.S. degree in physics from the University of North Dakota in 1977 and received a commission in the U.S. Air Force. While on active duty he earned an M.S. degree in physics from the Massachusetts Institute of Technology in 1984. At the Air Force Weapons Laboratory he investigated radiation effects on infrared focal plane arrays. After separating from the Air Force in 1988 he joined Sandia National Laboratories and is a Senior Member Technical Staff working on satellite sensor systems. He is responsible for design, analysis, procurement, and performance characterization of photodetectors and focal plane arrays for satellite payloads. Mary Ballard obtained a B.S. degree in electrical engineering from the University of California at Santa Barbara in 1988. She is a Focal Plane Array Systems Engineer at Raytheon Infrared Center of Excellence and leads a technical team to design, build and deliver focal plane / dewar assemblies. She is responsible for program planning, initial design concept, specification flowdown, and performance analysis of space qualified focal plane hardware. She has also developed test plans and characterized the radiation hardness of space sensor components.