Realization of vertical alignment with low pretilt angle by polymer-stabilize technique

A polymer-stabilized technique with a bias voltage (BPS) combined with a photo-alignment method has been applied for a vertical LC alignment to achieving stable and uniform pretilt angle as low as 80deg. An initially-pretilted vertically-aligned LC medium produced by a photo-alignment method, which is doped with a small amount of UV-curable monomer, is followed by a BPS method for further increase of the pretilt angle. The achieved pretilt angle as low as 80deg. by the combined method is very stable and uniform. This result clearly demonstrates the usefulness of the present BSP method to achieve very low pretilt angle for vertical LC alignment.