Highly accurate method for measuring ordinary and extraordinary refractive indices of liquid crystal materials, cell thickness, and pretilt angle of liquid crystal cells using ellipsometry

A new method for measuring the ordinary and extraordinary refractive indices of liquid crystal materials with high accuracy was devised by considering the multiple interferences in the liquid crystal cell. Refractive indices, liquid crystal cell thickness, and pretilt angle can be obtained from the numerical fitting between the measured and calculated values of the wavelength-amplitude ratio characteristics at one incidence and the wavelength-phase retardation characteristics at three incidences. We also devised a new extended Jones matrix method that considers multiple interferences. We experimentally confirmed the validity of our new method: the multiple-interference tri incidence (MITI) method. Highly accurate parameters can be obtained using the MITI method, and it is effective for the design of highquality liquid crystal displays.