Circular Unit Cell Gratings for X-ray Dark-Field Imaging

X-Ray Microscopy Conference 2016

Kagias, Matias^1,2 ; Pandeshwar, Amogha^2 ; Wang, Zhentian^1,2 ; Villanueva-Perez, Pablo^1,2 ; Jefimovs, Konstantins^1 ; Stampanoni, Marco^1,2

Swiss Light Source, Paul Scherrer Institute, Villigen, Switzerland^1

Institute for Biomedical Engineering, University and ETH Zurich, Zurich, Switzerland^2

关键词: Dark field imaging;    Grating design;    Grating interferometers;    Hexagonal grid;    Linear gratings;    Optimisations;    Single shots;    X-ray dark field imaging;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/849/1/012053/pdf
DOI  :  10.1088/1742-6596/849/1/012053

来源: IOP

【 摘 要 】

Dark-field imaging has been demonstrated to provide complementary information about the unresolved microstructure of the investigated sample. The usual implementation of a grating interferometer, which can provide access to the dark-field signal, consists of linear gratings limiting the sensitivity to only one direction (perpendicular to the grating lines). Recently, a novel grating design, composed of circular unit cells, was proposed allowing 2D-omnidirectional dark-field sensitivity in a single shot. In this work we present a further optimisation of the proposed grating by changing the arrangement of the unit cells from a Cartesian to a hexagonal grid. We experimentally compare the two designs and demonstrate that the latter has an improved performance.