A novel method for measuring and correcting the surface shape error of the pitch lap in the full-aperture continuous polishing

摘要

Continuous polishing is a significant process to fabricate optical workpiece with nano figure precision. The figure of theoptical workpiece is to a large extent dependent on the surface shape of the pitch lap. In this study, a novel method isproposed to determine the lap shape error by moving the measurement point in a generally radial direction while the laprotates and correct the lap shape error by employing a small heat tool considering its viscoelastic property. It is validatedthat the surface shape error of the pitch lap can be corrected dramatically by the method, and the workpiece figureattempts to target the lap shape so as to reach a uniform material removal.