Burvall Anna, Lundström Ulf, Takman Per A C, Larsson Daniel H, Hertz Hans M
Biomedical and X-Ray Physics, Royal Institute of Technology, AlbaNova University Center, SE-10691Stockholm, Sweden.
Opt Express. 2011 May 23;19(11):10359-76. doi: 10.1364/OE.19.010359.
In-line phase-contrast X-ray imaging provides images where both absorption and refraction contribute. For quantitative analysis of these images, the phase needs to be retrieved numerically. There are many phase-retrieval methods available. Those suitable for phase-contrast tomography, i.e., non-iterative phase-retrieval methods that use only one image at each projection angle, all follow the same pattern though derived in different ways. We outline this pattern and use it to compare the methods to each other, considering only phase-retrieval performance and not the additional effects of tomographic reconstruction. We also outline derivations, approximations and assumptions, and show which methods are similar or identical and how they relate to each other. A simple scheme for choosing reconstruction method is presented, and numerical phase-retrieval performed for all methods.
在线相衬X射线成像所提供的图像中，吸收和折射都起作用。为了对这些图像进行定量分析，需要通过数值方法来恢复相位。有许多可用的相位恢复方法。那些适用于相衬断层扫描的方法，即仅在每个投影角度使用一幅图像的非迭代相位恢复方法，尽管推导方式不同，但都遵循相同的模式。我们概述了这种模式，并利用它来相互比较这些方法，仅考虑相位恢复性能，而不考虑断层重建的附加影响。我们还概述了推导、近似和假设，并展示了哪些方法相似或相同以及它们之间的关系。提出了一种选择重建方法的简单方案，并对所有方法进行了数值相位恢复。
