X-Ray Phase Contrast Imaging (XPCI) augments absorption radiography with additional information related to the refractive and scattering properties of a sample. Grating-based XPCI allows broadband laboratory x-ray sources to be used, increasing the technique’s accessibility. However, grating-based techniques require repeatedly moving a grating and capturing an image at each location. Additionally, the gratings themselves are absorptive, reducing x-ray flux. As a result, data acquisition times and radiation dosages present a hurdle to practical application of XPCI tomography. We present a plug-and-play (PnP) reconstruction method for XPCI dark field tomographic reconstruction with sparse views. Dark field XPCI radiographs contain information about a sample’s microstructure and scatter. The dark field reveals subpixel sample properties, including crystalline structure, graininess, and material interfaces. This makes dark field images differently distributed from traditional absorption radiographs and natural imagery. PnP methods give greater control over reconstruction regularization compared to traditional iterative reconstruction techniques, which is especially useful given the dark field’s unique distribution. PnP allows us to collect dark field tomographic datasets with fewer projections, increasing XPCI’s practicality by reducing the amount of data needed for 3D reconstruction.
Johnathan Mulcahy-Stanislawczyk, Amber L. Dagel, "Plug-and-play sparse x-ray phase contrast dark field tomography" in Electronic Imaging, 2023, pp 157-1 - 157-4, https://doi.org/10.2352/EI.2023.35.14.COIMG-157