Single-step absorption and phase retrieval with polychromatic x rays using a spectral detector.

In this Letter, we present a single-step method to simultaneously retrieve x-ray absorption and phase images valid for a broad range of imaging energies and material properties. Our method relies on the availability of spectrally resolved intensity measurements, which is now possible using semiconductor x-ray photon counting detectors. The retrieval method is derived and presented, with results showing good agreement.