摘要 |
<p>An ultrasonic transducer unit for use in pulse-echo ultrasonic investigation has a plurality of components comprising a piezoelectric ultrasonic wave transmitting element (21), an acoustoelectric ultrasonic wave receiving element (22) and electrodes (23a,b,c,) therefor. To provide a compact and efficient transducer, these components are bonded together in an integrated multilayer structure in which the transmitting element (21) and receiving element (22) are superimposed in the direction of propagation of transmitted and received ultrasonic waves. The receiving element (22) may be a ZnO single crystal. An insulating layer (30) isolates two components from each other. <IMAGE></p> |