A simple expression is given for the power diffracted from a sequence of circular apertures and disks. The result is derived by use of the geometrical theory of diffraction, and is thus asymptotically correct in the short-wavelength limit. Several applications to the baffling of optical instruments are presented. An alternate approach based on the Huygens principle is also outlined and compared with the geometrical theory of diffraction.
W. A. Kleinhans, "Diffraction from a sequence of apertures and disks," J. Opt. Soc. Am. 65, 1451-1456 (1975)