US Patent 7666152 Focusing electromagnetic acoustic wave source

An acoustic wave device including an acoustic wave transducer adapted to generate an acoustic wave in a propagation liquid, the acoustic wave transducer having an inner contour defined by rotating a curve about a rotation axis of symmetry, wherein the curve and the acoustic wave are not parallel to the rotation axis of symmetry, and a focusing lens arranged with respect to the acoustic wave transducer so as to focus the acoustic wave emanating from the acoustic wave transducer to a focal point.