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Developments in X-Ray Tomography X, San Diego, California, USA, 29 Aug 2016 - 31 Aug 2016; Proceedings of SPIE 9967, 996718 (2016). doi:10.1117/12.2237582, Synchrotron X-ray imaging is constantly achieving higher spatial resolution. In the field of grating-based phase- contrast imaging, these developments allow to directly resolve the interference patterns created by a phase grating without need for a analyzer grating. In this study we analyzed the performance of a single-grating interferometer and compared it to a conventional double-grating interferometer. Based on simulations and measurements of a test phantom we evaluated the sensitivity, resolution and signal to noise ratios of different setup configurations., Published by SPIE, Bellingham, Wash.

The Imaging Beamline (IBL) P05 is operated by the Helmholtz-Zentrum Geesthacht and located at the DESY storage ring PETRA III. IBL is dedicated to X-ray full field imaging and consists of two experimental end stations. A micro tomography end station equipped for spatial resolutions down to 1 µm and a nano tomography end station for spatial resolutions down to 100 nm. The micro tomography end station is in user operation since 2013 and offers imaging with absorption contrast, phase enhanced absorption contrast and phase contrast methods. We report here on the current status and developments of the micro tomography end station including technical descriptions and show examples of research performed at P05.

We will present our study comparing the performance of a grating interferometer using a CMOS-based camera and a CCD-based camera. Our results show, that especially for grating-based phase-contrast the experiment benefits a lot from the reduced acquisition time with almost no decline in image quality or data accuracy using the CMOS-based camera.

Conventional absorption-based imaging often lacks in good contrast at special applications like visualization of soft tissue or weak absorbing material in general. To overcome this limitation, several new X-ray phase-contrast imaging methods have been developed at synchrotron radiation facilities. Our aim was to establish the possibility of different phase-contrast imaging modalities at the Imaging Beamline (IBL, P05) and the High Energy Material Science beamline (HEMS, P07) at Petra III (DESY, Germany). Here we present the instrumentation and the status of the currently successfully established phase-contrast imaging techniques. First results from measurements of biomedical samples will be presented as demonstration.

In this article we present the quantitative characterization of CCD and CMOS sensors which are used at the experiments for microtomography operated by HZG at PETRA III at DESY in Hamburg, Germany. A standard commercial CCD camera is compared to a camera based on a CMOS sensor. This CMOS camera is modified for grating-based differential phase-contrast tomography. The main goal of the project is to quantify and to optimize the statistical parameters of this camera system. These key performance parameters such as readout noise, conversion gain and full-well capacity are used to define an optimized measurement for grating-based phase-contrast. First results will be shown.