Photo-alignment of liquid crystals using a crosslinked discotic film

A new photo-alignment layer using a crosslinked discotic compound was demon strated. This discotic compound exhibits excellent solubility in common org anic solvents, the possibility of low temperature processing and good therm al stability. A linearly polarized long wavelength ultraviolet (LPUV) light (lambda = 350 nm) was used to initiate the crosslinking process and induce liquid crystal alignment on the discotic film surface. The induced LC dire ctors were found parallel to the electric field direction of the LPUV light . A 1.2 degrees pre-tilt angle was achieved using a single exposure at a 30 degrees oblique angle.