A simplified way is proposed to compute the paraxial diffraction of a zone plate. The complicated diffraction field is approximated by an equivalent field, which is the diffraction field of a hole weighted by the area. Based on this equivalent expression of the diffraction field, a graphic method is applied to calculate the resolving power of a zone plate. The result is consistent with those reported in earlier publications [Am. J. Phys. 19, 359 (1951); J. Opt. Soc. Am. 57, 610 (1967)].
© 1994 Optical Society of America
Original Manuscript: July 27, 1994
Published: December 1, 1994
Busun Xiao, "Equivalent field of paraxial diffraction of a zone plate," Opt. Lett. 19, 1940-1942 (1994)