An improvement of back-scattered ultrasonic tomography

Via a simple algorithm given by the Bent approximation one can reconstruct a tomographic image of the sound speed of an acoustically penetrable body; knowing its scattered sound field. This method is based on the hypothesis o f weak contrast between the body and the external medium. Otherwise the ima ge is a distorted version of the object. The distortion is characterised an alytically: Thus we propose a modified algorithm that cancels the image def ects so as to obtain a fast and reliable reconstruction method. (C) Academi e des sciences/Elsevier, Paris.