Imaging properties of multifocal systems with diffractive optical elements and Fabry-Perot interferometers

The imaging proper-ties of optical systems with phase diffractive mulifocal lenses are compared with those inherent in systems with diffractive amplitude masks in the form of a series of narrow concentric ring slits and in systems with Fabry-Perot interferometers. It is shown that the systems to be compared realize essentially the same multiple-coaxial-imaging effect observed at the focal planes equally spaced along the optical axis. At these focal planes, the point spread functions of the systems with diffractive multifocal lenses are found to have smaller first parasitic diffraction sidelobes than those of the equivalent systems with amplitude masks and Fabry-Perot interferometers.