A method for alignment processing including making a substrate 4, coated with an aligned film, closely face the photo mask 7 having a first mask pattern group having a plurality of elongated first openings formed at a fixed array pitch and a second mask pattern group provided in parallel with the first mask pattern group and having a plurality of elongated second openings formed at the same pitch as the array pitch of the first openings and moving the substrate in a direction crossing the first and second mask pattern groups, applying P polarizations with different incidence angles θ to the first and second mask pattern groups of the photo mask, and alternately forming, on the aligned film, first and second slit alignment regions in different aligned states.