Various mechanisms underlie metal-insulator transitions in condensed matter. One of these mechanisms is Anderson localization, which is caused by quantum interference induced by disorder. As a consequence, the Drude diffusion of an electron through the sample has to be corrected, and when the interferences become large enough, conduction may cease, leading to an insulating phase. Because the origin of this phenomenon lies in interference, it has been suggested 40 years ago by Anderson himself that it should be easily observed using "classical" waves as light or sound. A signature of localization lies in the transmission transverse profile: in the diffusion regime, a Gaussian beam spreads in time whereas in the localization regime it saturates. This transverse profile beam spreading should be independent of transmission. The intern will perform an experimental test of the independence of the claim that the transverse profile spreading in the presence of Anderson localization does not depend on absorption.