Reliable phase retrieval at 150 kVp

One of the goals of our Prosperity Partnership was to push the energy at which it is possible to perform phase-based imaging towards higher x-ray energies. By working with Microworks on the development of thick (300 micron) gold substrates, made possible by the relatively large size of our apertures, and optimizing the phase retrieval to effectively handle partial x-ray transmission through the mask septa, we were able to retrieve phase and dark field signals at spectral energies of 150 kVp, while proving the quantitativeness of the retrieved signals is preserved.

Acquiring a dark-field image of a 9V PP3 battery at 90 kVp (a) proves difficult, as photon starvation through the densest parts of the object leads to failure of the retrieval process in several pixels (white spots, more clearly visualized in the zoomed-in image in (c). Performing the same task at 150 kVp (b, d) solves the problem.