8 February 2002 Far-infrared calibration sources for use in cryogenic telescopes
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IR calibration sources have been built using a 'reverse bolometer' approach. A NiCr thin film is deposited on a thin sapphire chip, forming a robust, resistive heater with high emissivity. The heater is suspended within a metal ring using nylon fibers, and electrically connected with low thermal conductivity wires. Finished devices may be mounted directly ona cryostat work surface and provide a wide range of greybody output with minimal power dissipation to the cold bath. Under typical operating conditions, a 40K equivalent blackbody output can be obtained with 1 to 2 mW electrical input power. The time constant varies according to type of device and specified temperature, but ranges from 100 ms to seconds. Accelerated lifetime test show output repeatability to within +/- 0.8 percent throughout 94,000 cycles from 4.2 K to 60K. The devices have survived shake testing at cryogenic temperatures and will be used for in- flight array calibration in the Multiband Imaging Photometer for SIRTF instrument, a part of the SIRTF.
© (2002) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jeffrey W. Beeman, Jeffrey W. Beeman, Eugene E. Haller, Eugene E. Haller, } "Far-infrared calibration sources for use in cryogenic telescopes", Proc. SPIE 4486, Infrared Spaceborne Remote Sensing IX, (8 February 2002); doi: 10.1117/12.455107; https://doi.org/10.1117/12.455107


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