Abstract

Modern commercially available phase measuring interferometers (PMIs) can provide, in appropriate environments, repeatability of a few nanometers. A number of authors^1,2,3 have described methods which may be implemented on such instruments to provide high accuracy calibrations of flat and spherical optics. Such measurements are typically performed at "null", ie with a single fluffed out interference fringe. In this case, all the optics in the system from the Fizeau reference surface to the detector are common path and hence introduce no significant aberrations.

© 1994 Optical Society of America