Abstract

The removal of mid-spatial frequency features on aspherical surfaces is challenging because traditional pitch polishing methods used for spherical surface fabrication, that are inherently absent of these errors, are destructive to the low order aspherical surface form. Further, the measurement of aspheric surface errors offer a real challenge and require accurate methods of characterization in order to correct for those errors. This paper presents results obtained from novel fabrication and measurement techniques used to reduce mid-spatial frequency surface errors. The measurements were then used to develop polishing methods to eliminate these errors achieving less than 2nm rms residual error while preserving the aspheric form to better than 30nm PV.

© 2012 Optical Society of America