Simple method to obtain accurate pretilt angles for thin twisted nematic liquid-crystal cells

Abstract

Modern thin-film-transistor-driven twisted nematic (TN) products on the market require thin cell gaps below the value to satisfy the condition of the Gooch-Tarry first minimum in transmission for fast response times and wide viewing angles. For the first time to our knowledge, we have developed a simple experimental method based on a new configuration of out-of-plane cell rotation and analyzed our data by extended Jones matrix method to obtain accurate pretilt angles for such thin TN cells where the well-accepted configuration of the out-of-plane cell rotation method analyzed by Birecki and Kahn [ The Physics and Chemistry of Liquid Crystal Devices (1980), p. 115] was insufficient to address. (C) 2013 Optical Society of America