SINGLE TRANSDUCER GENERATION OF UNIPOLAR PRESSURE WAVES

In this letter, we present a method to generate short unipolar pressur e pulses using a single piezoelectric transducer. Such systems are of great interest in many fields, for instance. nondestructive testing. T he system is composed of a thin piezoelectric material coupled with a waveguide and a backing medium. It is shown that by applying a step vo ltage, the system acts as a high amplitude short duration unipolar pul se/generator. A particular experimental procedure has been used to com pare the emitted pressure pulse with the predicted one, without using a piezoelectric detector. Pulses of 90 ns width and 0.5 MPa amplitude are shown. (C) 1996 American Institute of Physics.