高衍射效率亚波长结构Dammann光栅的设计

传统的Dammann光栅是基于标量衍射理论设计的二值相位等光强分束器件，其衍射效率的典型值为80%左右.基于严格耦合波分析理论和遗传算法，提出了一种设计亚波长结构Dammann光栅的新方法，且该新型二值相位光栅具有较高的衍射效率.同时利用自编的仿真程序包设计了多个光栅，并分析了制作误差对其衍射效率和光强均匀性的影响.仿真结果表明，用该方法所设计的Dammann光栅的衍射效率超过92%.

Designing High Diffraction Efficiency Dammann Gratings with Subwavelength Structures

The conventional Dammann grating is a binary-phase uniform-intensity splitter designed by using the scalar diffractive theory,and the representative value of diffraction efficiency is about 80%.Based on the rigorous couple-wave analysis theory and the genetic algorithm,a novel method has been proposed for designing a new binary-phase Dammann grating with subwavelength structure,which has very high diffraction efficiency.At the same time,several Dammann gratings are calculated using the self-programming emulating package.Then the influences of fabrication error on the diffraction efficiency and intensity uniformity of gratings are analyzed.The simulation results indicate that the diffraction efficiency of Dammann gratings designed using this method is more than 92%.