Beam Steering of Electrically Segmented Piezo-Ceramic Ultrasonic Transducers Using Normal Mode Coupling

摘要

It is well known that normal mode coupling in large diameter piezoelectric plates causes serious difficulties when attempting to operate over wide frequency bands. As a consequence transducers are commonly constructed as a mosaic of elemental resonators, each of which has a predominant single mode of mechinial oscillation at the frequency of interest. Such transducer arrays may be electrically steered to angles other than normal by applying different phases of driving voltages to different elements.