Abstract
Glass-ceramic aspherical mirrors used as optical elements in space astronomical observatory must be machined with very high profile accuracy and surface smoothness. Precision grinding processes are very effective in fabrication of such profiles. In particular, ELID (Electrolytic In-Process Dressing) grinding method is possible to achieve ultraprecision smooth surface of hard and brittle materials. To obtain ultra smooth surface required by astronomical observatory, final polish process which required long time after conventional grinding process was necessary. ELID grinding method using an ultraprecision grinding machine tool with nano-level hydrostatic guide will be very effective in reducing the time required for finial polishing process. In this paper, a new ELID grinding system is introduced and experimental results of fabricating glass-ceramic paraboloidal mirror are discussed.
