Interferometric determination of the anisotropic refractive index dispersion of poly-(p-phenylene-vinylene)

The anisotropic refractive index of highly stretch-oriented free-standing films of polysp-phenylene-vinylened has been determined with high accuracy over a broad spectral range by using an interferometric method which directly measures the phase shift of a light-beam passing through the sample. The comparison with transmittance data allows one to evaluate the sample thickness with high precision, avoiding ambiguities in the extraction of the absolute value of the refractive index. The use of polarized light allows evaluation of the strong birefringence of the material.