Novel Achromatic Polariser For The Homogeneously Aligned Nematic Liquid Crystal Displays

Recent development of optical compensation scheme for liquid crystal display (LCD) enables to realise a high quality display by eliminating the unnecessary birefringence at oblique viewing directions. However, the red colour mura in a voltage-off dark state of homogeneously aligned LCD (HA-LCD) needs to be suppressed. In this report, we propose a novel optical compensation scheme for eliminating off-axis red colour mura by utilising a negative retardation tri-acetyl cellulous (TAC) film which results in a uniform spatial deviation of polarisation states for an incident white light. The proposed compensation scheme is demonstrated in detail by performing simulations and experimental studies, and high image quality of HA-LCDs without red colour mura in the dark state is realised.[GRAPHICS].