Off-axis polarizing properties of polarizing beamsplitter cubes

The field of view dependence of polarizing beam splitter cubes has been studied to characterize their behavior in imaging systems, such as optical computers, optical correlators, and other applications which involve non-collimated light. Significant polarization aberration is present in polarizing beam splitter cubes for two reasons, (1) the s and p orientations at the beamsplitting interface, which define the polarizing axes, vary with direction of propagation; and (2) the coating performance is a function of angle of incidence. Here we present measurements made on several polarizing beam splitter cubes from various vendors. The measurements show typical polarization behavior which is of concern when the cubes are used in imaging systems. A near infra-red imaging polarimeter is used to measure the cubes.