Two-dimensional measurements of cell parameter distributions in reflective liquid crystal displays by using multiple wavelengths Stokes parameters

Abstract

We propose a two-dimensional measurement method of cell parameters such as a cell thickness, twist angle, and pretilt angle in reflective liquid crystal (LC) cells by using Stokes parameters of reflected light at several wavelengths. The cell thickness of the reflective LC cells can be measured by calculating the Stokes parameter equations at only one wavelength, and both the cell thickness and twist angle can also be determined at two wavelengths, where the twist angle and/or pretilt angle of designed values are used. Three cell parameters including the pretilt angle as well as the cell thickness and twist angle can also be measured by using three wavelengths Stokes parameter equations. Two-dimensional LC cell parameters are easily obtained and their mapping results are successfully demonstrated.