全息反射镜的矩阵分析方法和数值模拟

Matrix Analysis and Numeric Simulation of Holographic Mirrors

提出采用特征矩阵的方法研究全息反射镜 (HM)的特性。在矩阵建立过程中考虑了介质折射率是连续变化的 ,并且根据全息介质的特性采用小波数近似 ,同时充分利用了光栅结构的周期性特点。该方法模型简单 ,物理意义直观、明确 ,并且只要增加细分层数值 ,或将幂级数展开到波数k的更高阶次 ,就可以提高计算精度。该方法不受“近布拉格入射”条件的限制 ,光栅周围的不同介质只要附加相应的特性矩阵就可以解决。对不同厚度、不同折射率调制度的全息光栅的反射率。

A simple and explicit characteristic matrix analysis is used to deal with the holographic mirrors (holographic volume gratings). The continuously varying of the refractive index is considered, and according to the property of holographic material, the small wavenumber approximation is utilized and the periodicity of the grating is used. The calculated precision can be improved by increasing the number of sublayer or developing the terms of power up to higher. The method does not be restricted to region of “near Bragg incidence” and is suitable to solve problems of gratings bounded by two different media. Then the reflectivities, the angular selectivities and the wavelength selectivities of several gratings are computed as numeric simulation.