Abstract

Given a substrate and incidence angle, combinations of refractive indices for two transparent layers are determined that provide a specified differential phase shift and equal p- and s-polarization reflectances. The method utilized to determine this constraint on the film indices has been published.¹ For nonideal retarders, with polarization-dependent reflectances, a numerical method is described that finds all film thickness pairs that achieve a specified differential phase shift for given indices and incidence angle. From these film thickness solution pairs, the thickness pair that provides the most equal p- and s-polarization reflectances is plotted for discrete film-index pairs. Both the ideal and nonideal solutions are plotted simultaneously for an absorbing and nonabsorbing substrate, incident angles of 30, 45, and 60°, and 90 and 180° reflection phase retardation angles.

© 1988 Optical Society of America