Silicon Lighweight Mirrors (SLMs) for UV and Extreme Ultraviolet Imaging Mirrors

Subtopic 01-S1.06 requires mirrors with a diameter of 0.5-2.4 meters, areal density <20 kg/m2, a figure specification of 0.02-0.005 waves rms @633nm, a surface roughness 0.5-1 nm rms, and a midfrequency error of 1.0-2.5 nm rms for use in the IR to EUV waveband. Schafer?s Phase II objective is to use Silicon Lightweight Mirrors (SLMS), a novel, all-silicon, foam-core, lightweight mirror technology, to build three imaging mirrors for the Next Generation Space Telescope Near Infrared Camera (NIRCam) Engineering Test Unit: M0 (a flat), M2 (a concave sphere) and M3R (an oblate spheroid). The surface figure error specification for the NIRCam imaging mirrors is 8 nm rms (0.013 waves rms @633 nm), equivalent to that required for UV and EUV mirrors, and this figure must be maintained at the 35 K operational temperature of NGST. The surface roughness required is 30 ? rms since NIRCam operates in the VIS/IR (0.65-5 ?m). We will produce mounts for mirrors M2 and M3R using the complementary thermally matched C/SiC material demonstrated by Schafer under another NASA SBIR, NAS8-98137.SLMS technology will significantly impact and benefit a very broad set of future NASA Space Science Enterprise (e.g., Explorer Program) and Earth Science Enterprise (e.g., GOES-R) missions. SLMS will provide a national benefit beyond NASA for DoD (Directed Energy, Imaging), DoC/NOAA (Remote Imaging) and commercial system houses (Ball, Raytheon, ITT, et.al.).