Abstract

Background Commercial micro X-ray fluorescence (mu XRF) systems often employ a tilted convergent beam, which can cause a misalignment between X-ray cartography and the corresponding visible images. This misalignment is typically considered a disadvantage, as it hinders the accurate spatial correlation of elemental information. However, this apparent drawback can be exploited to facilitate X-ray stereoscopy.Objective To demonstrate the use of unmodified commercial mu XRF equipment to estimate the 3D configurations of metals and voids within a low-atomic-weight matrix, specifically polymethyl methacrylate, and to explore the implications for enhancing mu XRF mapping techniques. This approach could have applications in materials science, archaeology, and other fields requiring non-destructive 3D chemical mapping.Methods Using unmodified commercial mu XRF equipment, we leveraged both XRF and Compton scattering effects to quantitatively reconstruct the size, position, and depth of embedded tungsten, copper, and silver objects. The study specifically examines how beam divergence affects the acutance of objects located deeper within the sample.Results Our findings indicate a depth estimation bias ranging from 4% to 15% for depths between 24 mm, and a size estimation bias below 3.2%. These results validate the methodology and highlight the robustness of our approach under typical operational settings, suggesting that the technique could be applied to a wide range of samples with minimal modifications to existing mu XRF systems.Conclusions The study confirms that the inclination-induced misalignment in mu XRF systems can be harnessed to enhance three-dimensional imaging capabilities. Our work establishes a foundation for advancing current mu XRF mapping techniques and interpretation strategies, potentially broadening the applications of mu XRF in various scientific and industrial fields.