DESIGN OF LOW-LOSS WIDEBAND ULTRASONIC TRANSDUCERS FOR NON-INVASIVE MEDICAL APPLICATION

In recent years ultrasound has become an effective and practical tool for obtaining information from within the body or about different kinds of materials without exposing them to X-rays. Proper design of the ultrasonic transducer is the key to a successful equipment patient interface. The emphasis in this paper is put on the design of low-loss wide-band transducers. The approach we have used consists of impedance matching the front face of the transducer with the propagating medium and totally unmatching the rear face. The front face matching is achieved using one or two quarter-wave layers, depending on the desired bandwidth. Several transducers have been built to illustrate this design, and a good agreement between theory and experiment has been achieved. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc.