对称膜系偏光分束镜特征参量的入射角效应

为了研究入射角对对称膜系薄膜偏光分束镜性能的影响,从等效膜层理论和截止带理论出发,采用图像法分析了分光光谱带宽和透过率随入射角的变化趋势和原因。利用UV3101-PC分光光度计测量了(LHL)^N膜系偏光分束镜在不同入射角下的透射分光光谱,实验结果与理论分析一致。结果表明,分光光谱带宽和入射角存在直接联系,分光光谱带宽随入射角的增大先变宽后变窄,存在一个带宽最大值,以带宽最大值对应的入射角为基点,减小入射角时,分光光谱带宽向长波段漂移并且出现凹陷;增大入射角时,分光光谱向短波段漂移。这些结果对优化对称膜系薄膜偏光分束镜有一定的参考价值。

The incident angle effect of symmetric periodic multilayer polarizing beam splitter

In order to study the effect of incident angles on the characteristics of symmetric periodic multilayer polarizing beam sputter (PBS),based on equivalent layers concept and stop-hand theory, the bandwidth of spectrum and transmittance change with incident angles were analyzed with the graphical method. The transmittance spectrum of(LHL)^N PBS was measured with a UV3101-PC spectrometer.The experimental results show that the bandwidth spectrum becomes wider and then narrower with incident angles increase, so there is a maximum bandwidth. Taking the point corresponding to the maximum bandwidth as a reference point, the transmittance spectrum moves to longer-wave band and appears hollow aperture with the incident angle decreases;on the other hand,the transmittance spectrum moves to shorter-wave band with the incident angle increases.The experimental results are consistent with theoretical ones.The results provide an important reference for design and optimization of the symmetric periodic multilayer PBS.