多层膜优化设计方法

The Optimizing and Designing Method of Multilayer Film

传统多层膜设计所用的全局寻优法的速度非常慢,有时还很难得到理想的膜系。根据Frensnel反射系数公式计算多层膜的反射率,利用单纯形法对软X射线和X射线波段多层膜进行调优,可在短时间内优化出最接近目标光学性能的多层膜膜系结构。计算了不同波长软X射线周期性多层膜的最高理论反射率。单纯形调优算法在保证优化结果与随机搜索法优化结果近似相同的基础上,使优化计算速度提高了十倍以上。同时还用单纯形调优法优化设计了X射线超反射镜,得到了非常理想的非周期膜系。

Since the global optimization seeking method used in the traditional multilayer design is very slow and difficult to get an ideal film system, an optimizing method based on the well-known Frensnel equations and simplex optimization is used in the design of optical element of multilayer for soft X-ray and X-ray. The highest theoretical reflectivity of a soft X-ray periodical multilayer at different wavelengthes is calculated, and the results are same as those calculated by the random search method, but the computing velocity of the simplex optimization is much faster than the random search method. The simplex method is also used in the optimizing design of the X-ray super-mirror, and the ideal result is obtained.