亚四分之一波长宽波段多层膜的设计

简要阐述了强吸收波段亚四分之一波长多层膜的设计方法。这种膜系是由强吸收材料叠加而成,每层膜光学厚度小于四分之一个波长。与常规周期多层膜相比,这种膜系更适用于提高强吸收波段的反射率。利用该方法设计了50nm~110nm波段宽带高反膜的初始膜系,通过Levenberg-M arquart方法对初始膜系进行优化,从而得到宽波段的平坦反射率,其平均反射率达到45%。

Design of sub-quarter-wavelength broadband multilayer reflectivity mirror

The design of sub-quarter-wavelength multilayers with enhanced normal reflectance in the strong absorbing wavelength range 50nm~110 nm were presented.The multilayer consists of a few layers of strong absorbing materials.The optical thickness of each layer is less than quarter-wavelength.Compared to the standard quarter-wavelength multilayer,this multilayer structure is suitable for the strong absorbing wavelength range.In this paper,high reflectance multilayers were designed at wavelength of 50 nm by using this method,and then optimized based on this initial condition by using Levenberg-Marquart algorithm in a wide wavelength range 50nm~110nm.The calculated result suggests that the reflectance of the multilayer is as high as 45%.