Abstract

It is widely known that the image of a tilted object (or equivalently, the image formed by a tilted optical component) suffers keystone (trapezoidal) and anamorphic distortions. Although these are often referred to as first-order distortions, keystone is predominantly second-order in the pupil and field coordinates, and both can vary over wide ranges as the pupil and image are transferred through the optical system. Any distortion in the object seen by a particular surface changes the field dependences of all the aberrations introduced by that surface. Similarly, any distortion of the pupil presented to a particular surface will change the pupil dependences of all the aberrations introduced by that surface. Since both anamorphic and keystone distortions are highly asymmetric, their effects are to cause asymmetric changes to the pupil and field dependences of all the aberrations. Recognition of the origin of these unusual aberrations suggests new surface types for the design of general systems.

© 1986 Optical Society of America