Finite element analysis simulation and experimental verification of the stressed lap's deformation accuracy

The deformation accuracy of the stressed lap is crucial to the fit between the lap and mirror in the production of large aspherics with stressed lap technology. As a preliminary work, we analyze a prototype model with the assistance of finite element analysis tools and build it out based on the analysis results in order to verify the accuracy of the deformation. Test results show that both the high-order residual error and repeatability of deformation of the lap are within 1 mu m rms in an 80% diameter of the lap for common deformations, faithfully meeting the accuracy requirement in the polishing process. (C) 2011 Optical Society of America