平板波导凹面衍射光栅的设计  

Design of planar waveguide concave diffraction gratings

作　　者：周哲海[1] 

机构地区：[1]北京信息科技大学光电信息与通信工程学院

出　　处：《光学精密工程》2008年第6期993-998,共6页Optics and Precision Engineering

基　　金：国家973计划重点资助项目(No.2007CB935303)

摘　　要：为了精确设计平板波导凹面衍射光栅,提出了改进的刻槽位置递推计算方法。通过一组约束方程表示光栅刻槽位置,利用递推方法求得约束方程的数值解;为了提高计算精度,在方程组的数值求解过程中引入牛顿迭代算法。设计了两种特殊的光栅结构,即平接收场结构和平顶频谱响应结构,对采用不同方法的设计进行了对比。结果表明:采用改进的刻槽位置递推计算方法计算的结果与采用高级次光程函数级数展开法计算的结果相同,而采用原有刻槽位置递推计算方法的计算结果则随着刻槽序号的增加偏离误差越来越大。结果证明了这种设计方法不仅可以实现平板波导凹面衍射光栅的精确设计,同样适用于设计其它特殊结构的光栅,证明了该方法的实用性和有效性。In order to design a Planar Waveguide Concave Diffraction Gratings （PW-CDG） accurately, especially a special grating structure, a design method named Modified Recursive Definition of Facet Positions（MRD） was presented. The central position of grating facets could be obtained by two constraint functions,and its numerical solution was derived from a recursive formula approach. To improve the accuracy of computation,a Newton iteration procedure was introduced in the recursive approach to compute each facet position. Two typical design examples,a flat-fieled mount and a flat-top mount,were given to assess the necessity adopting Newton iteration procedure subsequently. Simulation adopting different design methods were compared with each other,comparison indicates that computed results by MRD are identical with that by Power-series Expansion of Light Path Function（PS） with higher power,both of them are more accurate than that of traditional Recursive Definition of Facet Position（RD）. It comes a conclution that the modification is crucial for the accurate definition of grating facet positions.

关 键 词：平板波导凹面衍射光栅 集成光学器件 牛顿迭代 

分 类 号：O436.1[机械工程—光学工程]