GEOMETRIC AND ALGEBRAIC ERRORS IN CALCULATING A TRANSDUCERS SPATIAL IMPULSE-RESPONSE

Two types of errors resulting from the numerical evaluation of a trans ducer's spatial impulse response function have been identified. One is geometric and is due to the mismatch between the emulated piston surf ace (approximated using many small planar elements) and the true surfa ce. The other error is algebraic and is due to the inexact formulation of the response of the emulated surface. The deviations from the true response were calculated for three different pistons, The results ind icate that the shape and placement of the elements are important for t he computational accuracy.