Engineering topics
Rutishauser, Simon
Publications and source records attributed to Rutishauser, Simon.
At-wavelength characterization of refractive x-ray lenses using a two-dimensional grating interferometer
We report on the application of a two-dimensional hard x-ray grating interferometer to x-ray optics metrology. The interferometer is sensitive to refraction angles in two perpendicular directions with a precision of 10 nrad. It is used to observe the wavefront changes induced by a single parabolic beryllium focusing lens of large radius of curvature. The lens shape is reconstructed and its residual aberrations are analyzed. Its profile differs from an ideal parabolic shape by less than 2 {mu}m or {lambda}/50 at {lambda} = 0.54 A wavelength.
Structured scintillator for hard x-ray grating interferometry
Grating interferometry at conventional x-ray tubes improves the quality of radiographies and tomograms by providing phase and scattering contrast data. The main challenge encountered when applying this technique at high photon energies, as required by many applications to obtain sufficient penetration depth, is to maintain a high fringe visibility. In this letter, we report on a substantial improvement in fringe visibility and according improvements in image quality achieved by replacing the absorbing analyzer grating of the interferometer with a structured scintillator grating. This development represents a significant step toward the implementation of this technique in industrial testing and medical applications.
Two-Dimensional X-Ray Grating Interferometer
We report on the design and experimental realization of a 2D x-ray grating interferometer. We describe how this interferometer has been practically implemented, discuss its performance, and present multidirectional scattering (dark-field) maps and quantitative phase images that have been retrieved using this device.
Directional x-ray dark-field imaging of strongly ordered systems
Recently a novel grating based x-ray imaging approach called directional x-ray dark-field imaging was introduced. Directional x-ray dark-field imaging yields information about the local texture of structures smaller than the pixel size of the imaging system. In this work we extend the theoretical description and data processing schemes for directional dark-field imaging to strongly scattering systems, which could not be described previously. We develop a simple scattering model to account for these recent observations and subsequently demonstrate the model using experimental data. The experimental data includes directional dark-field images of polypropylene fibers and a human tooth slice.