FOURIER DOMAIN TECHNIQUE TO COMPUTE TOMOGRAPHY SCANNER WITH DIGITAL RADIOGRAPHY CAPABILITY

1We are proposing a computerized tomographic (CT) dimensional measurement system that will remedy two of the major problems experienced by current methods: the distortions caused by CT artifacts, and the blurring caused by the system point - spread function (PSF). The distortions resulting from data nonlinearity will be corrected by a calibration process acting upon the x-ray data. The blurring errors will be avoided by performing the measurement in the Fourier transform domain. This method can be used to perform automated, nondestructive inspection of crucial parts, such as turbine blades and rocket nozzles, for which substandard dimensions can cause failure. The preliminary system is expected to measure wall thicknesses down to 0.5 mm with better than 1% accuracy, but the method can be used to measure much thinner walls in small components.