双矩形光栅衍射特性分析

Diffraction characteristics analysis of double rectangular gratings

双光栅系统的衍射—干涉效应非常重要,现从置于透镜前方的任意两个衍射屏出发,推出透镜后焦平面的光强分布可以用两个衍射屏的振幅透射率函数的相关来表示,然后把该结论用于两个完全一样的矩形光栅,得出了双矩形光栅在一些特殊间距时透镜后焦面上的光强分布可以表示为周期不同的三角形光栅透过率。

The double diffraction grating system＇s diffraction-interference effect is important,In this article, two random diffraction screens are placed in front of the len first, the light intensity distribution in the len＇s back focal plane can expressed by the correlation of the amplitude transmittance function of the two diffraction screens. Then the conclusion for two identical rectangular gratings, when double rectangular gratings with some specific distance, the light intensity distribution in the len＇s focal plane can be expressed as transmittance of triangle gratings with different cycle.