Computer-Optimized Design of Quarter-Wave Acoustic Matching and Electrical Matching Networks for Acoustic Transducers

An iterative computer program was developed to optimize the parameters for the acoustic matching layer(s) and the electrical matching network of a transducer for a minimum length of the impulse response. By including the interactions between electrical and acoustic matching in the authors' model, the quality of the transducers has been significantly improved. A 3.65 MHz center frequency transducer, made of Murata PZT, was constructed to verify the computer results. The impulse response was approximately 2-1/2 cycles long with a round trip insertion loss of 10.9 dB at the center frequency, and the 40 dB ringdown time was 1.5 ..mu..sec when working into a water load.