Optimized Filtered Back-Projection Tomographic Reconstruction Algorithm for the Step-Shift Scanning of a Sample

The variety of modern X-ray sources opens possibilities to conduct measurements of a wide range of different specimens. The range includes objects with various properties such as the density, the amount and types of defects, and the size which can significantly change from sample to sample. Due to the development of portable high energy X-ray sources like betatrons, it is now possible to investigate objects of big sizes. Although, the fact that the dimensions of such objects can exceed the dimensions of X-ray setups requires to develop new types of scanning geometries and to adopt the algorithms of reconstruction and visualization. The scanning of an object along its longest dimension is one of the ways for investigating such objects. In this article, we present the step-shift scanning approach and the adaptation of filtered back-projection algorithm for this type of measurement. The developed algorithm allows to obtain the visualization of the whole volume of the object from the combination of all scanning steps or to visualize the separate parts of the object from the truncated dataset.