The invention belongs to the technical field of precision optical device
processing, and particularly relates to a
processing method of an ultra-precision
sapphire crystal optical substrate. Aiming at the defects in the prior art and the
sapphire crystal processing difficulty, an optimization scheme is provided, and the efficiency is improved through rapid
grinding and
polishing; through high-temperature precise annealing and
acid etching, mechanical stress,
material structure stress and subsurface damage generated by rapid
machining are eliminated; the
surface shape is trimmed through classical
polishing of a flexible rubber disc, and the
surface shape precision is improved in combination with a ring
polishing copying process; and
ion beam local modification is used to eliminate classical method residual
surface shape errors, and finally polishing is carried out to improve the
surface roughness after
ion beam modification. According to the method, modern
rapid processing and classical fine control are fused, surface shape stability is guaranteed, precision and roughness are balanced, the problem that efficiency, precision and quality are difficult to consider at the same time is solved, substrate
distortion is improved,
optical quality is improved, and the method is adaptive to high-end application scenes such as high-power
laser and
semiconductor equipment.