We study the diffraction effect of gratings under partially coherent illumination generated by a source slit. Various fringe distributions from Lau fringes to the Talbot self-image can be observed by continuous adjustment of the slit width. An expression for describing the effect is derived in terms of an ambiguity function, which is a joint correlation among the functions of the source slit and the two gratings. It is concluded that the profile of the fringe pattern changes not only as the degree of spatial coherence is varied but also as one of the gratings is shifted in a lateral direction. The experimental results are in good agreement with the theoretical intensity distributions.
© 1988 Optical Society of America
Original Manuscript: January 5, 1988
Manuscript Accepted: May 20, 1988
Published: October 1, 1988
Liren Liu, "Partially coherent diffraction effect between Lau and Talbot effects," J. Opt. Soc. Am. A 5, 1709-1716 (1988)