The modelling and design of controllable composite transducers

Some performance characteristics of controllable composite transducers, comprising an apodized disc piezoceramic transmitter and an integral polymer film receiver, are described and verified on an experimental basis. Apodization of the transmitter, via a restive taper electrode design, is utilized to control the spatial distribution of the generated ultrasonic field. The wideband receiver may comprise a single-element polyvinylidene layer or alternatively can be configured as a one-dimensional multielement annular array. Using this combination the composite devices are shown to produce enhanced signal quality, particularly in applications such as imaging and materials characterization where some form of inverse signal processing is required