从白细胞形体结构的特点出发，建立了单核细胞的双层偏心球模型。基于米氏散射理论和电磁波界面传输理论，应用几何散射逼近方法得到了单核细胞的散射光复振幅函数，其数值计算结果与运用有限元方法计算的VirtualLab虚拟仿真结果一致。数值计算的结果表明散射光强的角分布出现了3种不同频率的光强调制。分析了这3种调制出现的物理机制，指出调制特性与细胞的形体参数及光学参数之间的关系：低频调制在细胞大小尺度内无变化；次低频调制与细胞的相对折射率和核质比有关；高频调制的缺失与相对折射率和入射取向有关。并且指出了在细胞核紧贴细胞的情况下会有调制畸变现象出现。这些结果为单细胞的精细光学检测和鉴别技术的提高提供了理论依据。

According to the morphological structures of leukocyte, the double layer eccentric-sphere model is established for a kind of single-nuclear cell. Based on the Mie scattering theory and interface transfer theory, the expressions of amplitude functions are revised by the geometrical-optics approximation. Results of numerical calculation are consistent with the results from the VirtualLab imitation system which calculate by finite element method. Results of numerical calculation also show that three kinds of intensity modulations with different frequencies can be found in the angular distribution. The physical mechanism about these three modulations has been analyzed. The relations between the modulation characteristics and the physical and optical parameters of the cell are obtained. The modulation distortion phenomenon will appear in the case of nuclei close to the cell. These provide a useful theory foundation for improving the measuring and identification technique of single cells.