Characterization method of the effective phase retardation in linear birefringent thin sheets

Characterization of the birefringence of materials offers the opportunity to develop applications and elements to manipulate the polarization of light. We propose a new method for characterizing the effective phase retardation based on the linear birefringent law. The proposed method is flexible and easy to implement; it also determines the retardation introduced by a linear birefringent as from an input polarization state and a specific output state generated by the rotated material. The method is evaluated experimentally by characterizing the birefringence of cellophane samples. (C) 2021 Optical Society of America