High Structural Efficiency, Silicon Lightweight Mirrors (SLMS)

In Phase II, AFRL/VSSV has interest in developing lightweight, athermal, infrared space telescopes. Athermal telescopes have utility for use in Multi-Access Laser Space Terminals for Transformational Communications operating at GEO, and for the SpaceBased Infrared System (SBIRS) Low surveillance mission operating at cryogenic temperatures. Silicon Lightweight Mirrors (SLMS) Athermal Technology provides the demonstrated enabling mirror technology for manufacturing lightweight, athermal opticalsub-assemblies and instruments, such as a telescope. SLMS Athermal Technology has been proven over the temperature of 27 K to 300 K in the NASA MSFC X-Ray Calibration Facility (XRCF) 4-foot chamber. During a 2002 vacuum cryogenic experiment, an F/3 SLMSUV Demonstrator Mirror produced for a NASA Phase I SBIR project experienced less than 10 nanometers figure change from 300 K to 27 K. The figure change for the mirror mounted in an unfinished prototype C/SiC assembly was less than HeNe /13.6 rmsHeNe, with less than  HeNe /100 rms hysteresis when returned to 300 K. A Lightweight Athermal SLMS Innovative Telescope (LASIT) would provide a technology breakthrough for both space laser communications and space surveillance applications.Schafer has at hand all the technologies required to manufacture a 30 cm aperture LASIT instrument.