Vector wave imagery using a birefringent lens

The imaging characteristics of a birefringent lens sandwiched between two polarizers is studied analytically. If the optic axis of the birefringent crystal is perpendicular to the lens axis, the system behaves as a bifocal lens for proper orientations of the polarizers. It is shown that the proposed system can be adapted either for apodization or for superresolution simply by rotating either of the two polarizers. It has greater depth of focus than conventional systems, as is evident from the results obtained, Expressions are obtained for the point spread function of such a system. Some specific cases are illustrated graphically. (C) 1998 Society of Photo-Optical instrumentation Engineers.