A Multi-Frequency Multi-Focal Length Ultrasonic Therapy Transducer

Abstract

A transducer system is described for hyperthermia applications. By changing only mechanical attachments, it is possible to have the system to function at different frequencies (0.5–3 MHz). Focusing of the ultrasound beam is achieved by a plano-concave perspex lens on the front surface of the transducer. A mechanical arrangement is used to change the lens and the disc to provide focal lengths ranging between 90–150 mm at different frequencies and intensities from the same transducer system.