用总极值方法进行零位光栅结构的最优设计

A Study on Zero Grating Design by Using The Integral Global Optimization Method

本文改变了传统的零位光栅优化设计方法,用亮域设计代替亮线设计,采用“积分型总极值”的最优化方法,进行了零位光栅结构的最优设计。优化设计变量是各条亮域沿横向坐标轴上的上、下限值,优化目标综合了光亮比、光通量主峰值及描述主峰徒峭程度的因子β。实例表明:采用文中介绍的数学模型和最优化方法不仅能得到各项指标均为良好的零位光栅结构,而且在满足一定的零位精度前提下,设计的亮条数目明显减少,使光栅结构有所简化。所采用的最优化方法在迭代过程中收敛速度也相当快。

Instead of the triditional ′bright line′ design for the zerograting,the′bright regions′ design along with the ′Integral Global Optimi-zation′ method is proposed in this paper.The positions of bright regions onthe axis along the grating are chosen to be the parameters.The merit functionconsists of the factors of the brightness contract K,the magnitude of mainpeak S_o,and the bandwidth of the main peak β.Several design examples are also illustrated in this paper.The results showthat by using the mathematic model and the optimization method proposed inthis paper,not only the zero position gratings with high performance havebeen obtained,but also the constraction of the zero grating is significantlysimplified.