Han S T, Tsao Y L, Walser R M, Becker M F
Appl Opt. 1992 May 1;31(13):2343-52. doi: 10.1364/AO.31.002343.
We employed the rigorous vector coupled-wave theory [J. Opt. Soc. Am. 73, 1105 (1983)] to analyze the electromagnetic scattering from two dimensional (2-D) surface-relief dielectric gratings. A shoot-back method was developed for the numerical solution of the resulting coupled differential equations. This method allowed numerical solutions to be found for grating structures of arbitrary profiles and relatively deep grooves. It was most suitable where the grating medium refractive index was not too large and where only a small number of propagating orders existed. Experiments confirmed the numerically predicted reflectivities for 2-D surface-relief dielectric sinusoidal gratings. Reflectivity measurements were made on 2-D sinusoidal gratings fabricated on photoresist and on polycarbonate. The grating periodicities were of the order of 3000 lines/mm such that only the zero-order diffracted waves were propagating in the incident region, and possibly a few forward orders in the transmission region. The embossing technique that was used for replicating the grating patterns from photoresist onto polycarbonate proved to be a feasible method for the production of such gratings.
我们采用严格的矢量耦合波理论[《美国光学学会志》73, 1105 (1983)]来分析二维（2-D）表面起伏介质光栅的电磁散射。针对所得耦合微分方程的数值解，开发了一种回射法。该方法能够找到任意轮廓和相对较深凹槽的光栅结构的数值解。它最适用于光栅介质折射率不太大且仅存在少量传播阶次的情况。实验证实了二维表面起伏介质正弦光栅的数值预测反射率。对光刻胶和聚碳酸酯上制作的二维正弦光栅进行了反射率测量。光栅周期约为3000线/毫米，使得在入射区域只有零阶衍射波传播，在透射区域可能有少数前向阶次传播。用于将光栅图案从光刻胶复制到聚碳酸酯上的压印技术被证明是生产此类光栅的可行方法。
