基于主成分分析的X射线微分相位衬度成像研究

项目名称： 基于主成分分析的X射线微分相位衬度成像研究

项目编号： No.11205157

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学II

项目作者： 王志立

作者单位： 中国科学技术大学

项目金额： 30万元

中文摘要： X射线相位衬度成像技术在过去二十多年来受到了日益广泛的关注，在生命科学等众多研究领域展现出广阔的应用前景。特别是X射线微分相位衬度成像方法，能够有效利用常规X光源，成为近年来X射线成像领域的研究热点之一。目前，X射线微分相衬成像通常采用相位步进法从实验图像中提取物体的吸收、相位和散射信息。然而，利用这种方法得到的物体信息存在着系统误差，是不准确的。尽管增加实验图像数目可减小系统误差，但会导致辐射剂量和辐射损伤的增加，在临床医学等剂量敏感领域是不可行的。为克服相位步进法的局限性，本课题提出基于主成分分析的X射线微分相分相位衬度成像新方法研究，能够准确、定量提取物体的吸收、相位和散射信息，不存在系统误差。X射线微分相衬成像新方法的发展将实现快速、准确的相位衬度成像，降低物体所受的辐射剂量和辐射损伤，有力推动X射线相衬成像技术在临床医学等领域的广泛应用。

中文关键词： X射线成像；相位衬度；光栅干涉仪；信息提取；单次曝光

英文摘要： In the last two decades, X-ray phase contrast imaging has attracted increasing attention, and a widespread application of this technique is expected in life sciences etc.In particular, X-ray differential phase contrast imaging has been one of the hot topics in X-ray imaging researches, since it allows an effective utilization of conventional X-ray tubes. Presently, the phase-stepping technique is adopted for information extraction from experimental images. However, the results given by the method is not accurate, and with systematic error. Although the error can be reduced by acquiring more experimental images, the radiation dose and subsequent damage will increase. These limitations hinder the application of the phase-stepping technique in dose-sensitive researches, such as clinical medical imaging. To overcome the limitations, X-ray differential phase contrast imaging based on principal component analysis is presented in this project. The novel method allows a quantitative and accurate extraction of the object absorption, phase and scattering information without systematic error. This novel method is applicable to both 1D and 2D differential phase contrast imaging. With the novel method based on principal component analysis, we predict fast and accurate X-ray phase contrast imaging, with reduced radiation dose

英文关键词： X-ray imaging；Phase contrast；Grating interferometry；Information extraction；Single shot