The photo-polymerized liquid crystal (LC) film aligned on a photo-alignment layer was investigated with varying polarizability of UV light exposing on the photo-alignment layer. Interestingly, the polarizability of UV light required to induce bulk LC alignment on the photo alignment layer was found to be very low down to 0.1, and UV light greater than 0.3 polarizability produced outstanding optical performance of the film. The films fabricated with low polarizability light exhibited comparable thermo-stability with one fabricated with high polarizability light. The results suggest that micro-patterned optical birefringence films (MP-OBFs) can be fabricated by using an incoherent multi beam mixing method, where the direction of polarization of UV light can be spatially modulated. A simple MP-OBF was fabricated by using a two beam mixing method, and it exhibited a quality 3D film performance. The method will be highly useful in various optical components such as the MP-OBF, optical retarders, polarization grating etc.