Figure 1

(A,C,E) Graphical demonstration of the amount of information contained in each signal, with respect to the location of the ROI for three array directivities: (A) Transducer array; (C) LIPA; (E) EMAT array. Red circle depicts ROI. Green and grey circles depict array elements with high or low directivity towards the ROI respectively. (B,D,F) directivity patterns for array elements from: (B) a transducer array; (D) a LIPA; (F) an EMAT array. Green areas highlight angles where directvity is higher than half relative to its maximum.