Coated retarders based on liquid crystal materials are typically aligned by brushing or photo-alignment. Recently, we have managed to combine the aligning and retarder function into a single material. Alignment of the new volume photo-alignable retarder (VPR-) material is induced in the bulk upon exposure to linearly polarized light. The new alignment mechanism opens up a new dimension for the design of optical retarders, especially when combined with conventional surface alignment, which allows to induce complex tilt and twist profiles.

We have studied liquid crystal (LC) alignment on UV-irradiated poly(vinyl cinnamate)(PVCi)films by using the texture observations and the anchoring energy measurements. Irradiation of the PVCi films with linearly-polarized UV light creates the optical anisotropy in the films, and the anisotropy can well align LCs perpendicular to the UV polarization. We discuss the LC alignment mechanisms and point out the important contribution from non-dimerized side chains of PVCi molecules. The anchoring energies on photo-processed PVCi films are shown to be smaller than those on conventional rubbed polyimide films. We propose a new method to generate pretilt angle on the photo-processed PVCi films, and successful results of pretilt angle generation are demonstrated. This method is applied to fabricate TN- and super-multidomain TN-LCDs, and the good electro-optical performance of the LCDs is confirmed.