SLMS(trademark) Athermal Technology for High Quality Wavefront Control of HEL Tactical Airborne and Relay Mirror Beam Control Applications (Postprint)

摘要

The operational environment for tactical airborne mission is typically on the order of -20 degrees C. Relay mirror systems typically must operate at colder temperatures, on the order of -50 degrees C. The desirable attributes for the mirrors and beam directors for systems operating under these conditions are high quality wavefront control. Wavefront control can be improved through the use of very low absorption coatings which minimize thermal distortion, by using mirrors that do not print-through their lightweighting structures at cryogenic temperatures, by improving the surface figure, surface finish and surface quality of the mirror, by using mirrors with high structural efficiency and excellent damping performance, and by using mirrors that have very high first fundamental frequencies of vibration which will not resonate in response to system disturbances. Since payload weight is an important system driver, lightweighting is also important for the mirrors. In Phase 1, Schafer demonstrated a 5-inch dual-band mirror and in Phase II we are demonstrating a 21-inch dual band mirror.