On laboratory scale a new nondestructive technique has been elaborated for the quality control of layered structures. This technique is called the ‘‘acousto‐optic technique’’ and it measures the modulation of ultrasound reflected by a layered material optically in amplitude and phase using laser beams crossing the ultrasonic beams (incident and reflected). The most important characteristics of layered structures which have been investigated are the thickness and the thickness variations within a layer and the presence of artificial defects. Only when the ultrasound is incident in the Rayleigh angle of the substrate material, the phase differences measured obtain important information on the quality of the layered structure. The experimental results underline the results already obtained from the theoretical models elaborated for this technique. ©1995 American Institute of Physics.