Nematic liquid crystal optical dispersion in the visible-near infrared range

A commercial variable angle spectroscopic ellipsometer from J. A. Woollam Company is modified in order to make possible measurements in guiding structures. The half leaky guided mode technique is realised for liquid crystal optical dispersion measurements. Features and problems related to experimental data interpretation and error sources in the refractive index measurements are carefully analyzed, achieving a final accuracy of 0.0002. We present the measured optical dispersion curves in the wavelength range from 0.5 to 1.7 mu m for two widely studied liquid crystals, namely E7 and 5CB.