Abstract

The requirements on figure quality of large optics, particularly in the mid to high spatial frequencies have pushed beyond the limits of resolution of some common wavefront analysis methods such as the reduction of interferograms. The smoothness requirement for some astronomical mirrors on spatial scales of a few centimeters is on the order of .01 Arms making fabrication and testing of these mirrors difficult. The advent of direct phase measuring interferometry with the use of high density CCD or photodiode arrays has provided a means to achieve the necessary resolution.

© 1986 Optical Society of America