Anisotropy-enhanced depolarization on transparent film/substrate system

The combination of spectrophotometry and variable-angle spectroscopic ellipsometry is used for the optical characterization of a system consisting of transparent polymer film on a transparent polycarbonate substrate. In the region of sample transparency a relatively large depolarization is observed in ellipsometry. This can be explained by the presence of anisotropy in the film or substrate. The possibility of distinguishing between the depolarization enhanced by film and substrate anisotropy is discussed and tested using several models. It is shown that it is not possible to distinguish between these effects.