Mid-high-frequency error suppression of small optical aspheric molds.

Abstract

To suppress the mid-high-frequency error of small optical tungsten carbide aspheric molds, it is proposed to quickly select the critical process parameters by simulating the residual error after convolution of the tool influence function (TIF). After polishing for 10.47min by the TIF, two simulation optimizations, RMS and Ra, converge to 9.3 and 5.347nm, respectively. Their convergence rates are improved by 40% and 7.9%, respectively, compared to ordinary TIF. Then, a faster and more high-quality multi-tool combination smoothing suppression method is proposed, and the corresponding polishing tools are designed. Finally, the global Ra of the aspheric surface converges from 5.9 to 4.5nm after smoothing for 5.5min with a disc-shaped polishing tool with a fine microstructure and maintains an excellent low-frequency error (PV 0.0781µm).