基于X射线光栅成像的多衬度显微计算层析系统  

Multiple Contrast Micro-Computed Tomography System Based on X-Ray Grating Imaging

作　　者：戚俊成 任玉琦[1] 杜国浩[1] 陈荣昌[1] 王玉丹[1] 和友[1] 肖体乔[1,2] 

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100049

出　　处：《光学学报》2013年第10期312-319,共8页Acta Optica Sinica

基　　金：国家973计划(2010CB834301)

摘　　要：第三代同步辐射为X射线成像提供了一个单色、能量可调谐的高亮度光源。对于由低Z材料组成的样品来说,相比于传统成像方法,X射线光栅微分相位成像可以实现更高的相位衬度灵敏度,与计算机层析(CT)技术相结合还可以实现三维高密度分辨成像和折射率的测量。在上海光源X射线成像及生物医学应用线站,成功搭建了一套X射线光栅成像系统。基于此成像系统,利用同一套扫描数据可重构出吸收、相位和散射三种衬度信息;对于标准聚合物样品,系统可以高精度定量测量样品的折射率信息。测试结果表明,建成的X射线光栅成像系统可以实现低Z材料和生物医学样品的多衬度成像,有望在生物医学、聚合物材料等领域的无损、高衬度及定量成像研究中发挥重要作用。The third synchrotron radiation facility provides a brilliant source for X-ray imaging taking the advantages of its monochromaticity and tunability. For low-Z materials, X-ray grating based on differential phase contrast imaging can provide higher sensitivity than conventional X-ray imaging. Combined with computed tomography （CT）, it also can realize three-dimension high resolution imaging and measurement of refractive index. A set of X-ray grating based on imaging system is installed at the X-ray imaging and biomedical application beamline at Shanghai Synchrotron Radiation Faclity. Based on this system, three kinds of contrast including absorption, phase and scattering can be retrieved separately based on a single set of projections. According to test results for the standard sample of three different kinds of polymer, the refractive index decrement can be achieved. All these results demonstrate that the established X-ray grating imaging system can provide multiple contrast imaging and may play an important role in the nondestructive and quantitative imaging to biomedical and material samples.

关 键 词：成像系统 X射线光学 微分相位衬度成像 光栅干涉仪 暗场成像 同步辐射 

分 类 号：O434.1[机械工程—光学工程] O436.2[理学—光学]