Ultrasonic transducer apparatus

Abstract

In an ultrasonic transducer apparatus, one of ultrasonic transducer probes of a plurality of types is selectively connected to a driving unit. The ultrasonic probe includes an ultrasonic transducer having a series connection of an inductor, a resistor, and a capacitor, and a dumping capacitor connected in parallel with the series connection. The driving unit includes a driving circuit for supplying to the ultrasonic transducer a driving signal having a frequency where a phase difference between a voltage applied to the ultrasonic transducer and a current supplied to the ultrasonic transducer is substantially set to be zero, and an inductor connected to an output terminal of the driving circuit to be connected in parallel with the ultrasonic transducer. The inductor includes a plurality of intermediate taps having a different inductances, and each tap is connected to a connection terminal of the probe. The probe includes wiring for selecting the connection terminal so that an inductance corresponding to capacitive susceptance of the dumping capacitor of the ultrasonic transducer is connected in parallel with the ultrasonic transducer in a connector for connecting the probe and the driving unit.