Restauration d'images ultrasonores en contrôle non destructif

Abstract

The evolution of manufacturing techniques and the required quality show the importance of noninvasive diagnostics in industrial processes. Ultrasounds are widely used for this purpose, thanks to their innocuous character and their intrinsic qualities. In later years, the amelioration of ultrasonic techniques has required a number of improvements, including image processing. The present works focuses on the improvement of lateral resolution to optimize the localization and the size of the defects. To this end, we have developped a 3-D model that describes the propagation of ultrasonic waves and their interaction with a point defect. Reconstructing the image requires a 2-D deconvolution through an inverse filter. Tests made on Bscam images show clearly the efficiency of this technique to improve the image resolution.[Journal translation]