The ellipsometric measurements of a curved surface

Abstract

A three-intensity imaging ellipsometric technique is proposed to investigate the surface topography as well as the refractive index profile (RIP) of a lens. The azimuth deviation of polarizer caused by the tilting of a SiO2 thin film on Si substrate was investigated after a careful calibration on the azimuth position of polarizer of the water-surface. The azimuth deviation of polarizer is proved to be the local surface normal; thus we can determine not only the radius of curvature of a Plano-Convex lens from the measurement, but also its incident-angle-corrected RIP.