ABSTRACT
This chapter provides a description of the basic liquid-crystal properties relevant to liquid-crystal display and a guide to the important device structures. A variant of the nematic phase is described as cholesteric, simply because the first materials demonstrating this property were cholesterol derivatives. The study of liquid-crystal phases continues to reveal unexpected behavior, such as the chiral SA and the discotic phases. The strength of the disclination is given by s, which must be an integer or half-integer. A solution to the supertwisted nematic (STN) color problem is provided by the double-layer method, where a second STN cell of countertwist is positioned to optically compensate the originally addressed STN device. The response time is expressed in terms of a rotational viscosity 7, and for the radial spherical droplet it is written while for the elliptical droplet the response time is Fast decay in zero electric field favors low viscosity, small droplets, strong elasticity, and a large elliptic aspect ratio.
