中文摘要：

X射线组合透镜是一种利用折射效应对X射线聚焦成像的新型元件。本文结合衍射理论和统计学理论，推导得出X射线组合透镜近焦点处的三维聚焦强度分布公式，并以此为基础对X射线组合透镜的结构参数进行设计。计算得出了PMMA、Si、Al三种材料的X射线组合透镜在不同工作波长下的强度增益、焦斑尺寸和焦深等聚焦性能指标。并针对PMMA材料X射线组合透镜，分析了近焦点处三维聚焦性能随组合透镜结构参数的变化关系，给出了一种PMMA材料X射线组合透镜的设计结果。根据设计的组合透镜结构参数，计算了当X射线工作波长为0．15nm时，X射线辐射经过组合透镜后的近焦点处的强度分布。

英文摘要：

The X-ray compound lens is a novel refractive X-ray optical device. The authors report their recent theoretical and numerical study of such a device, including the derivations of the three-dimensional intensity distribution near focus based on the diffraction theory and the probability theory. As an example, the three-dimensional focusing performances such as intensity gain, the size of focus and the depth of focus are predicted for PMMA, Si and AI materials. The relationship between the three-dimensional focusing performances and the structural parameters of the PMMA compound X-ray lens is analyzed. And then a PMMA X-ray compound lens is designed. In addition, the numerical applications of the designed PMMA compound X-ray lens are also shown in the present paper for the working wavelength of 0.15nm.