Non-Destructive Testing (NDT) is inspection, test, or evaluation of materials, components or assemblies for discontinuities, or differences in characteristics without destroying the serviceability of the sample. Standard radiographic X-ray imaging provides a black and white intensity or density image of the inspected sample where defects, impurities or cracks are observed if the resolution and the signal over the noise of the image is appropriate. The spectral NDT X-ray imaging based on photon counting provides additional material information of the samples together with a superior contrast and high spatial resolution.
The spectral material information is used to discriminate different materials that can be used to identify the materials of interest or to calculate their amount in the sample. A single exposure high resolution spectral image taken with WidePIX 5×5 CdTe of a PCB unveils different components in different colors.