We present a description of a polarizer rotating-polarizer compensator spectroscopic ellipsometer called PRPCSE. This configuration is particularly adapted to characterize transparent film/substrate arrangement. We developed a procedure for the calibration with a single configuration of the optical elements (i.e. the same configuration for the calibration and the measurement). This method depends neither on the sample used nor on the gain of the ellipsometer, and the exact knowledge of the compensator phase shift value is not necessary. As for the measurements, this method allows to determine the tan psi and tan Delta parameters of the sample and is adapted to minimize systematic errors. It presents a special advantage when Delta is close to zero because the experimental errors are proportional to cos(2) Delta compared to a conventional rotating polarizer ellipsometer where the experimental errors are proportional to sin(-1) Delta. We show the potentialities of this ellipsometer for the measurements of transparent substrate with a sample of CuCl nanocrystals in NaCl matrix. A good precision of the measured parameters was obtained. (C) 2003 Elsevier B.V All rights reserved.