Wide viewing angle and fast responding TN LCD

Abstract

A new type of TN display device has been fabricated by sandwiching a dual frequency addressable nematic liquid crystal material between two unrubbed polyimide coated glass plates. Between crossed polarizers, the bright state is observed by applying a high frequency electric field, while the dark state by applying a low frequency electric field of similar strength. This dual frequency addressed rubbing free device shows very wide and highly symmetric viewing angle characteristics, with contrast ratio comparable to that of a rubbed TN device, and with very fast response time. Addressing the device in a "dual frequency dual amplitude pulsed mode" leads to only a small increase (~1.5 times) in power consumption in comparison with the conventional single frequency addressed device.