Distortion correction method for aspheric optical testing

摘要

Highly aspheric optical components are being used more frequently as increased bdemands are placed on optical system performance. The use of aspheric optics can simplify an optical design while increasing optical system performance. However, the effects of spatial distortion when testing fast off-axis optics can present a significant challenge to both designing the optical test-set and to post-processing the test data. Correcting for spatial distortion by post-processign the measured data is one approach that can be taken to increase the convergence rate when polishing an optic to a given prescription. This paper discusses the effects of spatial distortion at the exit pupil resulting primarily from the combined effects of geometric perspective distortion and mapping error. A software method for spatial distortion correction is presented along with the use of a distortion verification grid for verifying the accuracy of an applied distortion correction.