Integrated Detector Cooler Assembly for Space Applications-ICC17

ABSTRACT
Integrated detector cooler assemblies are widely used in tactical military applications to integrate coolers with an infrared focal plane into an evacuated dewar. Because the space environment is already evacuated they have rarely been used in space payloads despite their test advantage prior to launch. In this paper we report the design, fabrication and test of an Integrated Detector Cooler Assembly (IDCA) that was designed for space around our micro cryocooler and that could be easily modified to accommodate a wide variety of MWIR and SWIR focal planes. The IDCA is a hermetically sealed evacuated dewar containing an optical window, a cold shield, provision for a cold filter, a 640x480 pixel InSb focal plane, wiring to a 41 pin hermetic connector and cooled by the integrated pulse tube cold finger. The IDCA is a variant of previous devices that have been built in quantity for tactical applications whose environmental requirements exceed those typically found for space optical hardware. Since the typical focal plane dissipation (including this InSb focal plane) is much less than 100mW, and the parasitic loads are much less than the cooler’s rated capacity at 80K, this IDCA subsystem could also be used for some LWIR systems if the reject temperature is lowered.