Saha Nabarun, Kou Wen-Kai
Appl Opt. 2020 Dec 1;59(34):10700-10705. doi: 10.1364/AO.410673.
We propose a cost-effective narrow bandpass filter based on a guided-mode resonance (GMR) structure, operating at full conical mounting configuration. Two additional layers above the GMR structure with designed geometry is considered to create a large angle of incidence (AOI) on the GMR structure with an almost normal AOI on the entire structure. In the visible wavelength range, the transmission spectrum contains three peaks: two peaks that are due to the GMR effect and one that is due to thin-film interference. The modal characteristic of the two GMR peaks is identified using a matrix method for the n-layer waveguide structure. The two GMR peaks with bandwidths of ∼1 and ∼0.5 correspond to the fundamental TE and TM modes, respectively. The GMR peaks can be pushed away from the thin-film interference peak by modulating the grating depth.
我们提出了一种基于导模共振（GMR）结构的经济高效窄带通滤波器，其工作于全锥形安装配置。考虑在GMR结构上方增加两层具有特定几何形状的层，以便在GMR结构上产生大入射角（AOI），而整个结构上的入射角几乎为法线入射角。在可见光波长范围内，透射光谱包含三个峰：两个峰是由GMR效应引起的，一个峰是由薄膜干涉引起的。使用n层波导结构的矩阵方法确定了两个GMR峰的模式特性。带宽约为1和约0.5的两个GMR峰分别对应于基本TE和TM模式。通过调制光栅深度，可以使GMR峰远离薄膜干涉峰。
