Image reconstruction algorithm to X-ray diffraction tomography

The X-ray diffraction computed tomography technique is based on the interference phenomena. For low-momentum transfer, the scattering cannot be explained as being due to free atoms being necessary to consider solid-state scattering process. A selective discrimination of a given element in a scanned specimen can be realized by fixing the Bragg angle which produces an interference peak and then, to carry out the computed tomography in the standard mode. The photon source was a fixed tungsten anode X-ray tube emitting 26.4 keV photons. The reconstructed image represents the spatial distribution of the elastic cross-section, which is a function of the position within the sample and the scattering angle. Tomographic images obtained in diffraction mode were reconstructed with a back-projection reconstruction technique by using the implemented algorithm.