Two-Dimensional Displacement Analysis of Acoustic Transducer Arrays

Typical array elements for ultrasonic visualization systems have resonance frequencies and geometrical dimensions (width/thickness) such that their resonant behaviour and two-dimensional displacement field patterns can be described by solving the Rayleigh-Lamb equations. In this work, the Rayleigh-Lamb approach is extended to a multi-element structure and the dispersion characteristics together with the displacement distributions are computed. The effects due to different materials used as separating layers between the neighboring piezoelectric elements in also taken into account. By computing the mechanical displacements and the electric field configuration when one or more piezoelectric elements are excited, a good understanding of the mechanical and electrical coupling between the elements is obtained.