ASPHERO5 – Simulation and Analysis of Aspherical Polishing Process

Abstract

ASPHERO5 is a funded German research project (project prime: Schneider OpticalMachines) with the goal of economic fabrication of high precision aspheres. The research is concentrated on the classical process chain consisting of grinding and polishing. The characterization of the incoming and outgoing surface quality is one issue to characterize the improvements. The variation of the local removal rate related to local curvature is one of the limiting factors of the polishing process. In this paper we report on first results characterizing the surface quality with a PSD (Power Spectral Density) algorithm and analyzing the local removal rates for the polishing step. In our research, two types of aspheres with 30 and 60 mm diameter were polished with a spinning tool process. The final deviation between simulation and experiment was less than 10 percent. That’s the starting point for further investigations within the project.