Abstract
The condition to finish up the optical glass (BK7) surface in mirror finish by grinding processing was examined. The flat grinding was done by using three kinds of precise grinders with several resinoid bonded diamond wheels. In the brittle materials such as the glass generated brittle fracture and cracks on the ground surface. It was found that the brittle fracture depends on depth of cut by traverse grinding with #1500 wheel. In order to reduce the brittle fracture by decreasing the grinding force, the flat grinding face of the diamond wheel was modified in a spherical shape. As a result, the surface roughness Ra 1nm and the flatness 0.4 μm was obtained.
