Multiple-scattering theory of wave diffraction by superposed volume gratings
Multiple-scattering theory of wave diffraction by superposed volume gratings
复制标题
叠加体光栅波衍射的多重散射理论
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
Hyuk Lee
中科院分区：
文献类型：
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作者：
K. Tu;T. Tamir;Hyuk Lee
我们提出了一种有效的多次散射方法来研究介电常数包含重叠周期调制的介质的波的绕射，例如在厚全息图或其他涉及叠加体光栅的应用中发现的那些。为此，我们考虑平面模型中的序列波散射，该模型具有两个相互倾斜任意角度Δϕ的周期变化。因此，我们表明，所有的衍射场都可以用流程图来描述，这些流程图提供了对波散射过程的物理洞察。然后，我们研究了特别相关的小角度间隔Δϕ的情况，并发现可以通过在数学公式中应用简单的流程图考虑来评估各个衍射级。这一过程很容易提供准确的数值结果，以及在引入简化近似时所产生的误差估计。此外，我们还证明了双栅格模型可以很容易地推广到具有任意多个叠加周期的情况。
We present a powerful multiple-scattering approach to wave diffraction by media whose permittivity contains overlapping periodic modulations, such as those found in thick holograms or in other applications involving superposed volume gratings. For this purpose we consider sequential wave scattering in a planar model having two periodic variations that are inclined at an arbitrary angle Δϕ with respect to each other. We thus show that all the diffracted fields can be described by flow diagrams that provide physical insight into the wave-scattering process. We then examine the particularly relevant case of small angular separations Δϕ and find that the individual diffracted orders can be evaluated by applying simple flow-graph considerations to the mathematical formulation. This procedure readily provides accurate numerical results, together with an estimate of the errors incurred if simplifying approximations are introduced. Furthermore, we show that the two-grating model can be readily extended to situations having any number of superposed periodicities.