Incidence of element distribution on the ultrasonic field of segmented annular arrays

Segmented annular arrays are sometimes used for 3D ultrasonic imaging. Howe ver, owing to their geometrical complexity, the acoustic field generated by this type of aperture has not been adequately described. In this work, a m ethod based on the array factor approach is used to describe the field radi ated by sector annular arrays. This approach allows one to analyse the infl uence on the field of several aperture parameters, such as the number of el ements per annulus, size and spatial distribution of elements, etc. In addi tion, strategies to reduce grating lobes are presented. (C) 2000 Elsevier S cience B.V. All rights reserved.