Ameen D B, Bishop M F, McMullen T
Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000, USA.
Biophys J. 1998 Nov;75(5):2520-31. doi: 10.1016/S0006-3495(98)77697-0.
The method of photonic band structure is used to calculate the frequencies of light that propagate in lattice models of the cornea and sclera of the mammalian eye, providing an explanation for transparency in the cornea that first properly accounts for multiple scattering of light. Each eye tissue is modeled as an ordered array of collagen rods, and photonic band structure methods are used to solve Maxwell's equations exactly for these models, a procedure that automatically effectively includes all orders of multiple scattering. These calculations show that the dispersion relation for the cornea is linear in the visible range, implying that the cornea is transparent. We show that the transmissivity is approximately 97% by using an effective medium approximation derived from the photonic band structure results and applicable in the visible region. In contrast, the dispersion relation for the model in the sclera is not linear in the visible region, and there are band gaps in this region that could play an important role in the transmission of light in the sclera.
利用光子带结构方法计算在哺乳动物眼睛角膜和巩膜的晶格模型中传播的光的频率，为角膜的透明度提供了解释，首次恰当地考虑了光的多次散射。每个眼组织被建模为胶原纤维棒的有序阵列，并且使用光子带结构方法为这些模型精确求解麦克斯韦方程组，该过程自动有效地包含了所有阶次的多次散射。这些计算表明，角膜的色散关系在可见光范围内是线性的，这意味着角膜是透明的。我们通过使用从光子带结构结果导出并适用于可见光区域的有效介质近似，表明透射率约为97%。相比之下，巩膜模型的色散关系在可见光区域不是线性的，并且在该区域存在带隙，这可能在巩膜的光传输中起重要作用。
