Transflective liquid crystal display having mutually complementary patterned electrode and reflector

Abstract

A transflective liquid crystal display with uniform cell gap configuration throughout the transmissive and the reflective display region is invented. Mutually complementary common electrode pattern and reflector pattern or mutually complementary ITO pixel electrode pattern and reflector pattern produce an electric field in the transmissive display region that has a uniform longitudinal field and an electric field in the reflective display region that is a fringing field. An initially vertically aligned negative dielectric anisotropic nematic liquid crystal material between the electrodes forms a smaller tilt angle with respect to the substrate normal in the reflective display region while a larger tilt angle with respect to the substrate normal in the transmissive display region. Consequently, the ambient incident light experiences smaller phase retardation in the reflective display region while the light from the backlight source experiences larger phase retardation. Since the ambient light passes through the reflective display region twice while the light from the backlight source passes through the transmissive display region only once, by properly designing the electrodes and the reflector width, the light from both ambient light source and backlight source will experience almost the same phase retardation in both reflective and transmissive display regions. As a result, the electro-optical performance curves of both-transmissive display mode and reflective display mode overlap.