TeO2-CdF2-WO3 glasses with various compositions and Er3+ concentrations were prepared by conventional melting method. Their optical properties were studied by measuring the absorption, luminescence spectra and the decay patterns at room temperature. From the optical absorption spectra the Judd-Ofelt parameters (Omega(r)), transition probabilities, branching ratios of various transitions, and radiative lifetimes were calculated. The absorption and emission cross-section spectra of the I-4(15/2) to I-4(13/2) transition of erbium were determined. Emission quantum efficiencies and the average critical distance R-0 which provides a measure for the strength of cross relaxation were determined. (C) 2011 Elsevier B.V. All rights reserved.