Fabrication of Large-Diameter Single-Crystal Silicon Aspheric Lens by Straight-Line Enveloping Diamond-Turning Method.

The conventional method for aspheric surface diamond turning is the arc-enveloping method. In the present study, a new method termed the straight-line enveloping method is proposed, in which the aspheric surface is generated using a straight-nosed diamond tool on a three-axis simultaneous control ultraprecision machine tool. This method is preferable to the conventional method for the machining of convex aspheric surfaces on hard brittle...