提出了金属-介质-金属(MIM)结构三缝、四缝波导结构的增强型可见光分束器。利用表面等离子体效应及经典光学干涉原理，改变多缝波导结构中的填充介质、结构厚度、狭缝宽度及缝宽度等参数，可使波长不同的两束可见光通过多缝亚波长结构后实现分束效果。利用时域有限差分(FDTD)法进行数值模拟，发现多狭缝结构比双缝结构有更高的分束比。上述设计结构可以通过电子束刻蚀系统等实验设备加工，可应用于集成光学及光通信领域。

improved plasmonic dichroic splitter based on three and four subwavelength metallic slits metal-insulator-metal (MIM) stuctures is proposed. Different visible lights passing through the multi-slits structure produce optical splitting effects by filling with different insulators and setting the slit width, thickness of the waveguide structure of multi-slits. The splitting effects are explained by using surface plasmon's principle and classical optics interference principle. Numerical simulation by the finite-difference time-domain (FDTD) method is conducted to verify the design. Compared to two subwavelength metallic slits structure, the higher splitting ratio can be achieved in multi-slits structures. Those MIM designs due to the advantage of simple structures can be obtained by using experimental equipment such as electron beam lithography. Therefore, it has good application in integrated optics and optical communication fields.