A monopole ultrasonic pulse generator using PVDF piezoelectric film

Abstract

In this paper, a monopole ultrasonic pulse generator driven by a step-function voltage with a fast falling time is presented. We consider that the waveform and the pulse width of the ultrasonic is decided by the thickness of PVDF piezoelectric film transducer, the falling time of step-function voltage, the backing and the shape of acoustic propagation medium. The pulse generator is suitable to use for measuring the space charge distribution in solid dielectric, the width of pressure pulse is about 50 ns. It is also suitable for the other applications, e.g., the ultrasonic medical diagnosis. All these results are acquired through the piezo-PWP (Pressure Wave Propagation) measuring system applied for the study of space charge.