A single-thin-film model for the angle dependent optical properties of coated glazings

Abstract

Technology for the manufacture of coated glazings with spectrally selective optical properties, such as low-e and solar-control glazings, has been developed in the last few decades. This is leading researchers to develop new optical and thermal models in order to ascertain glazing performance. These new models must accurately reproduce the optical properties for any incident solar angle by using the available experimental data, which often means only information for normal incident radiation. In this paper, a new model is presented that characterizes the angular dependence of coated glazings. To provide a simple, intuitive understanding, this model uses only one thin film to characterize optical performance. In addition an optimization algorithm has been developed to obtain the spectral optical properties of that equivalent film using spectral experimental data under normal incidence. Finally, the model is validated with experimental data and the results are compared with other known models.