LAYER-BUILT ULTRASONIC TRANSDUCER

摘要

PURPOSE:To enable coping with different frequency by one transducer by forming a piezo-electric layer and an electrode alternately into a layer shape. CONSTITUTION:An ultrasonic transducer 21 is formed by alternately laminating four-layer electrodes 23-1-23-4 and three-layer piezo-electric diaphragms 24-1- 24-3 in a base body 22. For example, the transducer can be resonated at a frequency of 400MHz whose wavelength resonance length is 1/2, by using the electrodes 23-1 and 23-2 which are close to the base body 22. Utilization of said 23-1 and 23-3 makes it possible to use 200MHz. Utilization of said 23-1 and 23-4 makes it possible to use the device as the ultrasonic transducer 21 at 133MHz.