Analysis of impact factors on frequency distribution of optic surface

The precision optical system has increasingly tighter tolerance demand on optics for applications in science and industry. The detection and control of the frequency distribution of optical surface is a problem. Power spectral density (PSD) was used as a measure to characterize the frequency information about optical surface. The wavefront phase measurement data were transformed to the data in the system of polar coordinates by cubic spline interpolation, and the PSD-s ratio was calculated. The influence of the tool performance and its motion in computer controlled optical surfacing (CCOS) technique on the frequency distribution was analyzed. It was pointed out that the characteristics of frequency distribution could be efficiently controlled if the machining parameters were selected properly, which was validated by the manufacture process of a 670 mm diameter aspheric mirror.