TRANSVERSE RESONANCE ORTHOGONAL BEAM (TROB) SINGLE CRYSTAL UNDERWATER TRANSDUCERS

Abstract

Relaxor-based ferroelectric single crystals exhibit ultrahigh piezoelectric strain coefficients and electromechanical coupling factors. They are candidate materials for high-performance broadband medical, industrial and underwater transducers involving transmission and reception of large amounts of signals and information. In this research, using the excellent transverse piezoelectric properties and extremely high Poisson’s ratio of PZN-PT single crystals, a new drive mode for underwater projector, called the Transverse Resonance Orthogonal Beam (TROB) mode, has been devised. Unlike the conventional transverse width (CTW) mode or longitudinal (LG) mode in which the resonating direction and the acoustic beam direction are identical, in the TROB mode, the active material is set in resonance in one transverse direction and the acoustic beam is generated in either the conventional transverse width (CTW) or longitudinal (LG) acoustic beam direction, both of which being orthogonal to the resonating transverse direction.