INTERNAL COUPLING OF MULTIPLE-SIZED CAVITIES IN A CAPACITIVE ULTRASONIC TRANSDUCER

The internal leakage between resonator elements in capacitive ultrason ic transducers with V-grooved backplates has been studied. The phenome non is modelled and simulated using the lumped parameter method. The m odel can be used to explain signal vanishing at certain frequencies in capacitive ultrasonic transducers using multiple-sized resonators, i. e., cavities in the transducer backplate. The internal leakage togethe r with multiple-sized cavities can be used to increase the frequency b and of the capacitive ultrasonic transducer. (C) 1998 Elsevier Science S.A.