Combined X-ray diffraction and absorption tomography using a conical shell beam

We combine diffraction and absorption tomography by raster scanning samples through a hollow cone of pseudo monochromatic X-rays with a mean energy of 58.4 keV. A single image intensifier takes 90x90 (x,y) snapshots during the scan. We demonstrate a proofof-principle of our technique using a heterogeneous three-dimensional (x,y,z) phantom (90x90x170 mm(3)) comprised of different material phases. i.e.. copper and sodium chlorate. Each snapshot enables the simultaneous measurement of absorption contrast and diffracted flux. The axial resolution was similar to 1 mm along the (x,y) orthogonal scan directions and similar to 7 mm along the z-axis. The tomosynthesis of diffracted flux measurements enable the calculation of d-spacing values with similar to 0.1 angstrom full width at half maximum (FWHM) at similar to 2 angstrom. Thus the identified materials may be color-coded in the absorption optical sections. Characterization of specific material phases is of particular interest in security screening for the identification of narcotics and a wide range of homemade explosives concealed within complex "everyday objects." Other potential application areas include process control and biological imaging. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement