Abstract

Over the last ten years we have been developing a computer program for the efficient and accurate routine computation of the diffraction point spread function. The computation is accomplished in a two-step procedure in which one first employs ray tracing to compute the wavefront error in the plane of the exit pupil and to determine the shape of the vignetted pupil. Then one uses the standard Kirchhoff diffraction theory combined with the SSP method^1,2 for numerical integration to compute the field in the region of the image. The method does not rely on the small angle approximation and works well for a pupil of general shape. The diffraction patterns are presented as contour maps or graphs of intensity or phase of the field near focus. Routines for computing the optical transfer function from the diffraction patterns are also discussed.

© 1988 Optical Society of America