本文提出了任何平面物体的扩展Lau效应的新概念,相应提出了离轴光学博里叶变换系统的新的解释模型,导出了产生Lau效应的必要事件,也完整分析了光栅Lau效应,其中扩展了光栅的Frsenel成像条件.

A new idea is proposed to extend the Lau effect to any types of plane objects, and it is explained by a model of off-axis optical Fourier-transformation system. Two necessary conditions are deduced. First there must exist a definite correlation pattern between the intensity transmittances of two plane objects; second, the plane objects can be self-imaged by diffraction in a plane monochromatic wave of normal incidence. The Lau effect of two gratings is also discussed completely from the new viewpoint, where by the Fresnol's effect is extended. In this case it is easy to predict the profiltw oi Lau fringes from the correlation operation.