入射光的偏振特性对全内反射荧光显微术中荧光激发的影响

基于麦克斯韦的电磁场理论，研究了在全内反射荧光显微术中不同偏振态的入射光所产生的 不同偏振的隐失场以及对不同取向的荧光分子荧光发射的影响.理论分析结果表明，p偏振的 入射场将产生椭圆偏振的隐失场，s偏振的入射场将产生s偏振的隐失场.随着荧光分子三维 取向的不同，这两种隐失场的激发荧光效率也将不同，由此引起荧光发射强度的各向异性分 布.据此特性，可以实现对膜表面分子三维取向的成像. 关键词： 全内反射 荧光显微术 隐失波 偏振态

The influence of polarized light on fluorescence emission in total internal refl ection microscopy

Based on Maxwell equations, we have discussed the different evanescent fields made by excitation with different polarized incident fields, and their influence on fluorescence emission. Our analysis showed that the incident light of p-polar ization produces an ellipitically polarized evanescent field; at the same time, the incident light of s-polarization produces a pure s-polarization evanescent f ield. The probability of the excitation of fluorescent molecules by an evanescen t wave varies with the fluorescent molecules orientation, which will in turn res ult in the anisotropic fluorescence emission.