胶带的色偏振原理及其在演示实验中应用

日常用透明胶带以其各向异性可作为实验室中的简易波晶片来使用,再结合两片偏振片,即可用来探究光学中色偏振现象的各种规律。通过出射光光强、颜色、纯度等各种属性对胶带样品厚度、两偏振片偏振方向的夹角、胶带的拉伸方向与偏振片偏振方向夹角,以及观察角度之间的依赖关系,即可得出胶带的双折射性质;出射光颜色与胶带厚度的关系;出射光色纯度与偏振片角度的关系;出射光颜色与实验者观察角度的关联,并很好地与有关理论符合。将不同层数的胶带黏贴在两片偏光薄片之间以组成不同颜色的色块,即可应用上述规律自制一种创新的趣味性色偏振演示实验仪器。

Principle of Chromatic Polarization in Scotch Tapes and Its Demonstration in Experiments

The scotch tape can be used as a simple wave plate in laboratories because of its anisotropic refractive index.And by adding two polaroids,various laws with respect to chromatic polarization can be discovered.The birefringence,the relationship between the color of emergent light and thickness of the tape,the relationship between the purity of emergent light and the angle of the polaroids,the relevance of the color of emergent light and the viewing angle of the observer can be obtained by observing the dependence of the properties such as the intensity,color,and purity of emergent light on the thickness of the scotch tape sample,the angle beteen the polarization orientations of the two polaroides and the tensile direction of the tape,which are in good agreement with relevant theory.An amusing and innovative demonstration apparatus can be devised as a practical application of the above principles,if different layers of scotch tapes are put between two thin polaroids to form different color lumps.