New technologies improve passive LCDs and expand design flexibility

The author presents a review of new and existing LCD technologies and how they contribute to better performing displays. Included in the paper are discussions of typical applications and the technologies they use. The basic display types described are twisted nematic (TN), multidomain TN, first minima TN, supertwist nematic (STN), dichroic, and cholesteric-texture. The paper presents information on material and design advances that are driving improvements in existing displays and allowing new types of LCDs. This includes progress in LCD computer modeling, advances in retardation films to improve viewing angles and contrast, and new types of display cells and materials. Application of these technologies are being translated into specific types of hardware. For example, one of the new display materials results in bright, bistable displays without backlighting, thereby lowering power consumption. Other applications include touch screen LCD panels, LCD light shutters, and projection displays.