Development of a Cryogenic All-Silicon Telescope (CAIT)

Douglas R. McCarter, Eloise McCarter, Roger Paquin

McCarter Technology Inc dba McCarter Machine Inc


Mankind loves space and is drawn to explore its vastness.  Existing space telescopes routinely encounter data losses and delayed data collections during the constantly changing temperature and load disruptions of space missions.  The harsh environment of space thermal cycles and spacecraft motion loads create unwanted activity such as spacecraft slew, acquisition slew, and temperature induced blur.  In order to compensate for the low performance of the materials currently used for telescope optics, engineers and designers are using costly on-board coolers, mechanical actuators, and deformed mirrors, for example, with limited success.  However, Zero-defect Single Crystal Silicon (SCSi) can perform in space environments without coolers, actuators, and other such devices because SCSi is not ductile and is homogeneous and therefore is not subject to creep, and will not jitter, or blur during operations.  To take advantage of the unique advantages of Zero-defect SCSi, we are developing and fabricating a Cryostable All-Silicon Imaging Telescope (CAIT).   In this paper, we will discuss the basis for selecting SCSi for our space telescope design, the status of the CAIT design and fabrication progress, and compare SCSi thermal and strength properties with other typical space optical materials.

(Our paper can be downloaded here or email Doug McCarter at