Making (lambda)/200 rms spheres via a hybrid conventional/computer-controlled process

High quality optics have been manufactured using both conventional spindle polishing and small tool figuring under computer control. While both techniques have been used to produce precision optics in the past, this paper describes the hybrid process of using both processes to utilize their specific figuring efficiencies. By knowing the frequency content of the surface being corrected, the proper tool size can be selected to address the dominant frequency. By using the most efficient tool for correction fabrication time will be reduced yielding more cost effective processes. Proper process calibrations and controls are required to maximize convergence and material removal.