基于光流控技术对细胞分析仪器的重要应用，针对三叉型结构光流控的三维（3D）聚焦能力不足的现状，对传统结构的聚焦能力进行了动态分析，探明了影响3D聚焦能力的因素，设计了一种适用于白细胞光学检测的高效三维聚焦微流控通道结构。该结构应用两侧鞘液流的夹流，实现样本流的二维聚焦，通道内新增的凹陷实现样本流的第三维聚焦。通过聚焦面积、速度分布和粒迹分布的动态仿真实验，对所设计结构下的3D聚焦效果进行了对比分析，其结果表明所设计的结构具有更好的3D聚焦效果，这对于光流控芯片在细胞分析仪器中的开发和应用具有很好的潜在应用价值。

Optofluidic technique has an important application in cell analysis instrument. In view of the insufficient three-dimensional (3D) focusing ability of the trigeminal type-optofludic, the dynamic analysis of optofluidic with traditional structures is done, some factors affecting the 3D focusing are analyzed, and an efficient 3D focusing micro channel architecture is designed, which is suitable for the optical detection of white blood cells. The structure uses sheath stream flow’s press on both sides to achieve sample stream’s two-dimensional focusing. By adding the sags in the channel, it can achieve the sample stream’s 3D focusing. The focusing areas, velocity distribution and particle trajectory distribution under different kinds of sag are obtained with numerical simulation technique, and the corresponding 3D focusing effect is analyzed comparatively. Result shows that the proposed structure has a better 3D focusing ability and indicates that it will have a good potential application value for the optofluidic chip’s development and application in cytoanalyze.