本文基于自由空间的部分相干传递函数对效应提出了新的解释模型,给出了描述Lau条纹强度分布的普遍公式,它适用于任意周期性的振幅或位相型物体,对于几种典型周期性物体分析了Lau条纹产生的条件及输出强度.给出了不同周期的矩形光栅产生Lau效应的实验结果.

In this paper we present a new model for interpreting Lau effect on the basis of partial coherent transfer function in free-space propagation. The generalized formula for description of intensity distribution of Lau fringe is deduced. It is suitable for arbitrary periodical amplitude or phase objects. The condition of producing Lau fringe and output intensity for some typical periodical objects is analysed. The experimental results of Lau fringe produced by line gratings with different periods are given.