Four-domain twisted vertically aligned liquid crystal pixels using microrubbing

Microrubbing (μ-rubbing) technique is used to create four-domain twisted vertically aligned liquid crystal pixels for wide viewing angle displays. A metallic sphere of 1 mm diameter is used to locally rub a homeotropic polyimide surface to create a four-domain pixel. We use μ-rubbing to accurately control the surface pretilt angle of the liquid crystal from the normal, which directs the liquid crystal molecules to respective direction on applying a voltage. We report on twisted vertically aligned configurations with symmetric isointensity curves, high contrast, and attractive electro-optic performance. The optical simulations of the liquid crystal director orientation, viewing angle characteristics and switching behavior of the four-domain are also presented.