晶体膜层效应对棱镜偏光镜透射比影响的理论研究

Theoretical Research of Effect of Crystal Membranous Layer on Light Transmission of Polarizing Prism

为满足现代光信息技术对偏光器件各项技术指标的苛刻要求,利用膜层理论推导出线偏振光垂直入射时棱镜偏光镜透射比的数学解析表达式,并对影响棱镜偏光镜技术指标的每个物理参量作了定量分析。通过计算机定量模拟表明:晶体厚度对透射比的影响幅度与中间空气膜层的透射比有着密切的关系,在晶体折射率等参量取某些特定值,中间空气隙的厚度h=26.2μm和27.4μm时,格兰泰勒(Glan-Taylor)棱镜晶体厚度对总透射比的影响幅度分别为5.934%和7.034%,格兰傅科(Glan-Foucault)棱镜晶体的厚度对总透射比的影响分别为1.24%,8.893%;晶体厚度,空气膜层厚度,棱镜结构角共同影响棱镜偏光镜的透射比。这一理论研究克服以前棱镜偏光镜透射比公式不能定量分析晶体厚度对棱镜偏光镜透射比影响的缺点,对偏光器件的的设计,具有重要的应用价值。

For meeting rigor demands of modern light communication technology on each technic target of polarizer, a mathematically analytical expression of polarizing prism is deduced by means of theory of membranous layer when incident light is vertical to the crystal plane. Each physical parameter of affecting polarizing prism transmission technic target is analysed quantitatively. Computer simulations show that influential range of crystal thickness on transmission of polarizing prism associates with transmission of air inter layer. When parameters, such as crystal refractive index etc. are endowed with given values, for thickness of air inter layer h = 26.2 μm and 27.4 μm, influential ranges of crystal thickness on transmission of Glan-Taylor prism are 5. 934% and 7. 034% respectively, and influential ranges of crystal thickness on transmission of Glan-Foucaul prism are 1. 24% and 8. 893 %. Transmission of polarizing prism is affected by crystal thickness, air inter layer thickness and configuration angle. This theoretical research overcomes the shortcoming of previously transmission formulas of polarizing prism.They cannot analyse influence of crystal thickness on light transmission of polarizing prism quantitatively. The theory has importantly applied worthiness to polarimeter design.