【摘要】 提出了一种基于X射线衍射增强成像(DEI)断层计算机X射线层析术(CT)图像的物体尺寸精确测量方法。X射线衍射增强成像是一种基于相位衬度的成像技术。通过建立DEI的简化模型,研究衍射成像过程中晶体转角、投影图像谷点位置、成像系统等效模糊等因素之间关系,由此具体探讨了系统模糊效应对圆物体边界成像带来的位置偏移,并以圆形被测样品为例,提出可精确测定直径的简单有效算法。通过理论仿真模型数据和北京同步辐射装置上的实测数据验证了该算法的精度。该方法实现了利用DEI图像对被测物体几何尺寸的精确测量,可用于对生物组织样品等物体内部微小结构的尺寸的精确测量。更多还原

【Abstract】 A method for accurate measurement of the size of objects from X-ray diffraction enhanced imaging(DEI) and computer tomography was proposed.X-ray DEI is an imaging method based on phase contrast.A simple model of DEI was set up,by which the relationships among crystal angle,valley positions in image,and system blurring were studied.The deviation of projection valley points caused by the blurring effect was discussed,and a new method to measure diameter of a round sample from projective DEI profile was proposed.DEI data from both simulation and Beijing Synchrotron Radiation Faculty ware processed to demonstrate the validity and accuracy of the method.This method presents an accurate measurement method of the size for objects,especially for the inner structure of small biological tissues or samples.更多还原