简便快速的纳米分辨中能X射线成像相位提取方法

项目名称： 简便快速的纳米分辨中能X射线成像相位提取方法

项目编号： No.11305173

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 高昆

作者单位： 中国科学技术大学

项目金额： 29万元

中文摘要： 同步辐射X射线全场显微术能够对样品进行无损、三维、纳米分辨的成像，在材料、生命科学等领域、特别是完整细胞显微术方面有重要应用。但是传统软X射线显微术的焦深有限，不适用于直径大于5微米的细胞；另一方面，硬X射线显微术虽然焦深大，但是因其穿透力太强而对生物样品的成像衬度非常低。新近提出的中能X射线泽尼克显微术很好地弥补了两者的不足，能够对几十微米大小的细胞进行高衬度显微成像。本课题拟针对中能泽尼克相衬显微术中存在的相位提取问题，通过引入Nomarski微分干涉的思想，提出基于X射线双频光栅的微分干涉相衬成像方案。相比于传统的泽尼克相衬方案和其他定量相衬方案，本方案能够更为简便、快速地获取相位与吸收信息，进而为大细胞的折射率三维重建提供准确的数据。本课题的研究将为国内众多学科领域、特别是生命科学，提供更为方便准确的纳米形貌表征手段。

中文关键词： x射线显微术；相衬成像；微分干涉成像；相位提取；

英文摘要： Synchrotron radiation based full-field x-ray microscopy has significant applications in materials and cell imaging thanks to its non-destructive nanometer-resolution 3D imaging ability. As an important tool, however, conventional soft x-ray microscopy has a quite limited focal depth, therefore is inappropriate for imaging cells larger than 5 um. Another important tool, hard x-ray microscopy, does have a rather large focal depth, but inevitably accompanied with very low image contrast due to the high penetration power of hard x-rays to biological specimens. Recently, a novel x-ray microscopy technique has been suggested with both an acceptable large focal depth as well as a high contrast to biological specimens, using Zernike phase contrast mechanism with intermidiate enery x-rays. This NSFC proposal aims at solving the phase retrieval problem possibly existed in intermediate enery x-ray Zernike microscopy by introducing the idea of Nomarski differential interferential microscopy, therefore offers an improved differential phase contrast imaging method. Compared with conventional x-ray Zernike phase contrast method and other existing quantitative phase retrieval methods, the suggested method can retrieve accurate phase and absorption information in a single shot, therefore provides better data for 3D tomography re

英文关键词： x-ray microscopy；phase contrast imaging；differential imaging；phase retrieval；