Polarization state is of fundamental importance in electromagnetic scattering from periodic and random systems. Here we demonstrated that electromagnetic wave can be perfectly and achromatically transformed into its orthogonal polarization state by utilizing the huge anisotropy of meta-surface. More importantly, it is proved that the phase shift between two coherent inputs can be utilized to dynamically tune the polarization states of output waves. Depending on the phase difference, the outputs can be y-polarization, left handed polarization and right handed polarization for x-polarized inputs. (C) 2013 Elsevier B.V. All rights reserved.