Inorganic thin film compensator for improved gray scale performance in twisted nematic liquid crystal displays and method of making

摘要

An optical O-plate compensation device, in accordance with the invention, uses an inorganic thin film which is grown by physical vapor deposition at oblique incidence. The resulting thin film exhibits a biaxial form birefringence and performs, in a liquid crystal display (LCD), in a similar manner to uniaxial films with its extraordinary axis oriented obliquely at about 45 DEG with respect to the surface of the film. The invention makes possible a significant improvement in the gray scale properties and contrast ratios of liquid crystal displays (LCDs) over a wide range of viewing angles.