A simple method of phase-and-amplitude extraction is derived that corrects for image blurring induced by partially spatially coherent incident illumination using only a single intensity image as input. The method is based on Fresnel diffraction theory for the case of high Fresnel number, merged with the space-frequency description formalism used to quantify partially coherent fields and assumes the object under study is composed of a single-material. A priori knowledge of the object's complex refractive index and information obtained by characterizing the spatial coherence of the source is required. The algorithm was applied to propagation-based phase-contrast data measured with a laboratory-based micro-focus x-ray source. The blurring due to the finite spatial extent of the source is embedded within the algorithm as a simple correction term to the so-called Paganin algorithm and is also numerically stable in the presence of noise.
- X-ray optics
- Coherence theory
- Imaging systems
Beltran, M. A., Paganin, D. M., & Pelliccia, D. (2018). Phase-and-amplitude recovery from a single phase-contrast image using partially spatially coherent x-ray radiation: Paper. Journal of Optics, 20(5), . https://doi.org/10.1088/2040-8986/aabbdd