Piecewise isoplanatic modeling of space-variant linear systems
Shing-Hong Lin, Thomas F. Krile, John F. Walkup · Journal of the Optical Society of America A · 1987
A piecewise isoplanatic approximation (PIA) applicable to the classification of linear systems and the representation of space-variant linear systems is described. A new measure of the degree of invariance is developed and used as a tool to classify linear systems and determine optimal PIA patch sizes and critical points. Also, the relationship of the variation bandwidth to the new measure of invariance is utilized to support the validity of the new measure.