Two-dimensional ultra-small angle X-ray scattering with grating interferometry

It was recently established that the pixel-wise ultra-small angle x-ray distribution can be retrieved with grating interferometry. However, in these one dimensional approaches the contrast was limited to the direction orthogonal to the structure of the line gratings. Here, we demonstrate that sensitivity in two contrast directions can be achieved by using two pairs of crossed line gratings and by adapting scan procedures and data analysis accordingly. We demonstrate the retrieval of two-dimensional scattering distributions with grating interferometry, thus overcoming the previously reported limit of seven obtainable, complementary contrasts. In addition, we give further evidence for the superiority of the signal-to-noise ratio for the dark-field contrast, if a deconvolution-based instead of the standard analysis is utilized.