Ultra-high frequency cadmium-sulphide transducers

Cadmium-sulphide diffusion-layer transducers have been made in a variety of structures, with fundamental frequencies from below 100 Mc to above 1000 Mc for longitudinal mode, and to 300 Mc for shear-mode operation. Conversion losses from 7 db to 28 db with 15% bandwidth were obtained over this frequency range. A new transducer structure using evaporated thin films of cadmium sulphide has been investigated. These evaporated layer transducers have shown conversion losses of only 17 db at 1000 Mc with 20% bandwidth for longitudinal mode operation.