Interpretation von Ultraschall-Abbildungen

During the evaluation of ultrasonic images, e.g. SAFT-reconstructed B-scan images (SAFT=Synthetic Aperture Focusing Technique) it is often difficult to decide, what is the origin of reconstructed image points: were the caused by defects, specimens geometry of modeconversions. To facilitate this evaluation a tool based on the comparison of data was developed. Different kinds of data comparison are possible: identification of that RF-Signals, which caused the reconstructed image point. This is the comparison of a reconstructed image with the corresponding RF-data. Comparsion of two reconstructed images performing a superposition using logical operators. In this case e.g. the reconstruction of an unknown reflector is compared with that of a known one. Comparison of raw-RF-data by simultanous scanning through two data sets. Here the echoes of an unknown reflector are compared with the echoes of a known one. The necessary datasets of known reflectors may be generated experimentally on refer ence reflectors of modelled. The aim is the identification of the reflector type, e.g. cracklike or not, the determination of position, size and orientation as well as the identification of accompenying satellite echoes. The interpretation of the SAFT-reconstructed B-scan image is carried out by a complete description of the reflector. In addition to the aim of interpretation the tool described is well suited to educate and train ultrasonic testers.