Abstract
The thickness dependence of the Berreman effect for naturally grown oxide films on chrome is analyzed theoretically and experimentally. The shift of the spectral position of the Berreman minimum can be described by the Fuchs–Kliewer theory of virtual modes. Both the absorption and the shift of the position can be used for thickness determination. The experimental results compared with calculated values based on different optical constants for Cr2O3 indicate their influence on the position and the absorption of the Berreeman minimum.