Bergstein L, Shulman C
Polytechnic Institute of Brooklyn, NewYork, USA.
Appl Opt. 1966 Jan 1;5(1):9-21. doi: 10.1364/AO.5.000009.
The method of modal expansion is used to develop a theory for the analysis of frustrated total reflection (FTR) filters or similar layered systems of finite lateral extent. The theory is applied to determine the (spectral) transmission properties of the FTR filter of finite lateral extent (for an incident plane wave propagating in direction of maximum transmission). It is found that the finiteness of the lateral dimensions of the filter has a great effect on the transmission properties of the filter. The results are in agreement with available experimental data and clearly show that the unbounded wave theory (i.e., an analysis which assumes that both the incident electromagnetic radiation and the filter are of infinite lateral extent) cannot be applied to FTR filters even when the lateral filter dimensions are several orders of magnitude larger than the wavelength of the incident radiation.
模态展开法被用于发展一种理论，以分析受抑全反射（FTR）滤波器或类似有限横向范围的分层系统。该理论用于确定有限横向范围的FTR滤波器的（光谱）传输特性（对于沿最大传输方向传播的入射平面波）。结果发现，滤波器横向尺寸的有限性对滤波器的传输特性有很大影响。这些结果与现有的实验数据一致，并清楚地表明，即使滤波器的横向尺寸比入射辐射的波长几个数量级还要大，无界波理论（即一种假设入射电磁辐射和滤波器都具有无限横向范围的分析方法）也不能应用于FTR滤波器。
