A double-layered line-focusing PVDF transducer and V(z) measurement of surface acoustic wave

In this paper, we present a new ultrasound transducer and its measurement system for surface acoustic waves. The transducer has double-layered PVDF films; one acts as the transmitter of ultrasound while the other acts as the receiver. By forming the PVDF films into a concave cylindrical shape, a line-focusing transducer is formed and can be used for the V(z) measurement of surface acoustic waves and wave velocity measurements. The most important advantage of using the doubled-layered PVDF transducer is that the transmitting/receiving electronics can be greatly simplified. Furthermore, the operating frequency bandwidth can be extended significantly. In this work, the capability and accuracy of the transducer and its measurement system are demonstrated with both isotropic and anisotropic samples. Potential applications and further improvements are also addressed.