In this work, a rotating compensator sampling for spectroscopic imaging ellipsometry (SIE) is presented and demonstrated by characterization of a SiO(2) nanofilm pattern on Si substrate. Experiment results within spectrum of 400-700 nm show that the rotating compensator sampling is valid for SIE to obtain the ellipsometric angle distributions psi (x, y, lambda) and Delta (x, y, lambda) over the thin film pattern, the sampling times of psi (x, y) and Delta (x, y) with 576 x 768 pixels under each wavelength is less than 8 s, the precision of fitting thickness of SiO(2) is about 0.2 nm and the lateral resolution is 60.9 mu m x 24.6 mu m in the parallel and perpendicular direction with respect to the incident plane. (C) 2010 Elsevier B.V. All rights reserved.