A Computer Controlled Optical Surfacing (CCOS) process has been developed that is in routine use for fabricating off-axis and centered aspheric mirrors. An industrial robot effects surface removal by moving a relatively small tool over the mirror surface in a path covering the entire surface. The removal is computed by the convolution of the tool work function with the path of the tool over the mirror surface. The combination of CCOS with microgrinding (grinding with fine diamond powders that produce a specular surface) allows interferometric testing at an early stage of the process. Removal rates and tool conformance to the mirror surface are enhanced by vacuum applied to the grinding and polishing tools. Surface figure accuracies better than 0.02 μm rms and finishes better than 10 Å are currently achieved.

Date Published: 1 October 1991
PDF: 9 pages
Proc. SPIE 10260, Infrared Optical Design and Fabrication: A Critical Review, 102600E (1 October 1991); doi: 10.1117/12.48454

Published in SPIE Proceedings Vol. 10260:
Infrared Optical Design and Fabrication: A Critical Review
Rudolf Hartmann; Warren J. Smith, Editor(s)