Polarizing interferometer for the unambiguous determination of the ellipsometric parameters

Abstract

We report on a polarizing interferometer-ellipsometer arrangement that overcomes the need for additional measurements with a retarder for the unambiguous determination of the ellipsometric parameters in the far infrared spectral range. It consists of a Martin–Puplett interferometer and a wire-grid polarizer as an analyzer. The application of such interferometer-ellipsometer is experimentally demonstrated on a polyethylene sample deriving the refractive index and the thickness in the spectral range between 15 and 35 c m − 1 . Based on these results, a similar solution without a retarder for the mid-infrared spectral region is additionally proposed.