Aberration polynomial fitting and MTF based optimization for general optical systems

Abstract

Although there are different ways to implement MTF optimization1,2 in an optical design program, a common requirement of them is to express the wave-aberration as a polynomial in the exit pupil coordinates. While in-depth studies have been carried out for polynomial fitting for rotationally symmetric optical systems3,4, few publications can be found on the subject for general systems without symmetry. A simple scheme is developed for the efficient and accurate determination of the coefficients of a Zernike wave-aberration polynomial for a given object point and a general optical system. It enables rapid evaluations of MTF related image criteria such as the variance of the wave-aberration difference function, which is used as the merit function in damped-least-squares MTF optimization for nonsymmetric systems.