Heterodyne method for determining the surface tilt angle of nematic liquid‐crystal displays

Abstract— The high‐sensitivity pretilt‐angle measurement of liquid‐crystal displays, based on the modified crystal‐rotation configuration and the use of a common‐path heterodyne interferometer, is proposed. In this technique, environmental disturbance and surface reflection are eliminated to a large extend, thus providing advantages for both constructing a simple‐optics measurement system and achieving fast measurement with high accuracy and sensitivity.