Phase retardance elements such as quarter, half and full waveplates are essential elements in the most of the polarization systems. So, they should be determined precisely. Accurate determination of the phase retardation for these elements are necessary and critical due to its effect on the optical polarization measurements. In this paper we measure two-dimensional phase retardation distribution of half wave plate using four step phase shifting technique for accurate retardance measurements through the whole surface of the wave plate. By using this technique, four images are captured, which are related to different orientation of the azimuth angle of the analyzer, and mathematically analyzed to obtain the phase retardance measurements. The mean value of the phase retardance measurements is 182.57˚ with uncertainty 0.6˚.
Proposed method for phase retardation measurements using polarimetric techniques
