Variable-angle spectroscopic ellipsometer: Ellipsometry is a powerful tool for determining the optical indices and thicknesses of the layers in a thin-film coating especially when combined with radiometric data from our other instruments. This information is used both for analysis of our coating structures and to develop models for optical properties of various solar energy materials.

This ellipsometer can also be used in "scatterometer mode" in which it acts as a spectrophotometer with in-plane bidirectional goniometer function. The ellipsometer shown below by the J.A. Woollam Co. covers the ultraviolet, visible and near infrared range from 250-1700 nm.