We show that an arbitrary spatial distribution of complex refractive index inside an object can be exactly represented as a sum of two "monomorphous" complex distributions, i.e. the distributions with the ratios of the real part to the imaginary part being constant throughout the object. A priori knowledge of constituent materials can be used to estimate the global lower and upper boundaries for this ratio. This approach can be viewed as an extension of the successful phase-retrieval method, based on the Transport of Intensity equation, that was previously developed for monomorphous (homogeneous) objects, such as e.g. objects consisting of a single material. We demonstrate that the monomorphous decomposition can lead to more stable methods for phase retrieval using the Transport of Intensity Equation. Such methods may find application in quantitative in-line phase-contrast imaging and phase-contrast tomography.
Retrieval of multiple fibre orientations using X-ray dark-field signal modelling
CNR-Nanotec (Institute of Nanotechnology)（意大利国家研究委员会纳米技术研究所）；Fondazione Santa Lucia IRCCS（圣露西亚基金会IRCCS）；Diamond Light Source（钻石光源）；University of Salento（萨莱诺大学）；Tecnomed Puglia - Tecnopolo per la medicina di precisione (Biotech Lecce Hub)（普利亚科技医疗-精准医学科技园（莱切生物技术创新中心））；Department of Medical Physics and Biomedical Engineering, University College London（伦敦大学学院医学物理与生物医学工程系）
Low-dose, high-resolution CT of infant-sized lungs via propagation-based phase contrast
Monash University（莫纳什大学）；Hudson Institute of Medical Research（哈德森医学研究所）；ANSTO, based at the Imaging and Medical Beamline of the Australian Synchrotron（澳大利亚核科学和技术组织（位于澳大利亚同步辐射中心成像与医疗光束线））
