Ptychographic X-ray speckle tracking
Andrew J Morgan, Harry M Quiney, Sasa Bajt, Henry N Chapman
Journal of Applied Crystallography | INT UNION CRYSTALLOGRAPHY | Published : 2020
A method is presented for the measurement of the phase gradient of a wavefront by tracking the relative motion of speckles in projection holograms as a sample is scanned across the wavefront. By removing the need to obtain an undistorted reference image of the sample, this method is suitable for the metrology of highly divergent wavefields. Such wavefields allow for large magnification factors that, according to current imaging capabilities, will allow for nanoradian angular sensitivity and nanoscale sample projection imaging. Both the reconstruction algorithm and the imaging geometry are nearly identical to that of ptychography, except that the sample is placed downstream of the beam focus ..View full abstract
Awarded by Cluster of Excellence 'CUI: Advanced Imaging of Matter' of the DFG -EXC 2056
Funding for this project was provided by the Australian Research Council Centre of Excellence in Advanced Molecular Imaging (AMI), the Gottfried Wilhelm Leibniz Programme of the Deutsche Forschungsgemeinschaft (DFG), and the Cluster of Excellence 'CUI: Advanced Imaging of Matter' of the DFG -EXC 2056 -project ID 390715994.