A method for liquid crystal alignment using in situ ultraviolet exposure during imidization of polyimide

Homogeneous alignment of liquid crystals can be achieved by a technique usi ng polyimide films and in situ exposure to linearly polarized ultraviolet ( LPUV) light during imidization. The alignment layers prepared by this metho d exhibit higher thermal stability while requiring shorter processing time than the conventional UV alignment method which employs UV exposure after t he imidization of polyimide is complete. Multidomain cells can be easily fa bricated with the use of a photomask and multistep in situ LPUV exposure du ring hard bake. (C) 1998 American Institute of Physics. [S0003-6951(98)0294 9-0].