On the front face of a piezoelectric plate, electrodes split into an array form are disposed. Thus, there is provided a transducer of monolithic array type having an array of transducer elements operating independently, without cutting the piezoelectric plate. On the rear face of the piezoelectric plate,...http://www.google.fr/patents/US4692654?utm_source=gb-gplus-shareBrevet US4692654 - Ultrasonic transducer of monolithic array type
