9360761 Sudarshan Current processes for manufacturing sapphire introduce a number of defects such as die marks and growth artifacts in the as-grown sapphire blank. Thus these materials will need to be polished prior to use in optics. The objective of this Phase I effort is to develop a high quality, high speed, cost effective technique for polishing sapphire based optics. The two methods currently used for polishing sapphire are: mechanical and mechanochemical, both of which involve scraping, grinding and using abrasives such as diamond or colloidal silica. These methods are expensive because of the long times required for polishing. Further, due to the application of mechanical pressure, heat is generated at the polishing interface leaving behind defects that affect optical performance. Phase I will establish the proof of concept by using a dual stage non-contact method to remove planar layers of the sapphire thus achieving surface roughness on the order of angstroms in both flat and curved blanks. Optical characterization will be performed on the polished samples and correlated to the processing parameters. In Phase II, we propose expanding this technique for optical domes. This technique can also be used for other applications involving optical components such as laser cavity mirrors, laser beam mirrors, lenses, windows with high optical transmission, components in floptical disk drives and magnetic disk drives. **
