针对折射率调制的表面等离子体全息显示方案, 采用严格耦合波计算方法, 仿真了变折射率薄膜正弦光栅结构参数与衍射效率的关系.结果表明, 银作为表面等离子体激发材料时, 0.2 μm为光栅最优厚度, 在此基础上, 一级次光衍射效率与折射率差值、周期呈正比增长关系.对折射率范围进行了拓展, 确定了折射率调制范围在1.34~1.8、周期为0.9 μm时, 对应的衍射效率可达33%以上.研究结果对于优化设计表面等离子体全息显示结构具有参考意义.

For the surface-plasma holographic display scheme of refractive index modulation, the relationship between the structural parameters of the variable-refractive-index thin-film sinusoidal grating and the diffraction efficiency is simulated by using the rigorous coupled-wave calculation method. The results show that when the silver is used as the surface plasmon excitation material, 0.2 μm is the optimum thickness of the grating. On this basis, the diffraction efficiency of the first-order light is proportional to the refractive index difference and the period. The refractive index range is expanded, confirming that when the refractive index modulation range is 1.34~1.8 and the period is 0.9 μm, the diffraction efficiency can reach more than 33%. This study has reference significance for the design of surface plasmon holographic display structures.