Development of Broadband Underwater Transducers and Arrays

This paper describes the development of broadband underwater (U/W) transducers at Microfine Materials Technologies Pte Ltd, Singapore. A range of low-to- mid frequency (10-40 kHz) broadband U/W transducers of Tonpilz (TP) designs are available, including single crystal motor sections of spoke-like and square-pipe constructions and cost-effective versions driven by piezoceramic rings. Also available are new transmission-line (TL) design of acoustically-matched transmitter element of <<lambda(w)/2 in head mass diameter, lambda(w) being the wavelength in water at the operating central frequency. High-elemental density low-frequency arrays are possible with the new TL design. Together with high-frequency piezocomposite transmitter array, which is embedded among the small footprint TL elements, slim transmitter arrays for dual-/ triple-frequency synthetic aperture sonar (SAS) applications are now possible. Also described are other high-performance devices including miniature high-sensitivity hydrophones and vector sensors, as well as cost effective piezoceramic-based broadband 31-mode free flooded ring transducers of a few kHz in central frequency.