Characterization of annular array transducer
Pages 92-98
Luminita Moraru, Laura Onose, Ana-Maria Chiselev
Abstract
The aim of the current study was to compare the beam patterns for annular array with different annular number of elements in a homogenous medium. An alternative approach to linear arrays is to employ an annular array transducer, with a relatively small number of annular elements to focus the beam in the axial direction, resulting in 2D ultrasonic images with significantly increased DOF (depth-of- focus). Even it is expected that heterogeneous and attenuating biological media will degrade annular array performance we proved an improvement in DOF with annular array- focusing. This likely indicates that focusing with our annular array is more effective in the far-field than in the near- field of the transducer. First, we made this comparison for simulated transducer with equal area and different number of elements (4, 6 and 8 ring annular arrays) and 3.25 MHz frequency. Second, the frequency was changed and the results were compared. Finally the results obtained were interpreted and discussed