Temperature effect on liquid crystal refractive indices

Abstract

A model describing the temperature effect of liquid crystal (LC) refractive indices is derived and confirmed by experiment. Two single LC compounds (5CB, 5PCH) and two mixtures (MLC-6241-000 and UCF-35) with different birefringence values were used to validate the model. This model fits all the experimental data well. For a low-birefringence LC mixture, if the operating temperature is far below its clearing point, the temperature-dependent refractive indices can be approximated as a parabolic form. This prediction is also experimentally validated. In addition, a linear relationship between 〈n2〉 and temperature is found.