title: Bow-tie effect: differential operator.
abstract: We propose to use a differential operator for representing the influence of phase-only filters on the defocused modulation transfer function of the clear pupil aperture. We present a phase-only filter that implements optically Taylor's theorem in phase space. We show numerical simulations of the modulation transfer functions and the images that can be obtained by using the proposed filter.
authors.affiliation: Instituto Nacional de Astrofísica, Optica y Electrónica, Puebla, Mexico. betina@inaoep.mx
authors.forename: Albertina
authors.initials: A
authors.lastname: Castro
authors.forename: Jorge
authors.initials: J
authors.lastname: Ojeda-Castañeda
authors.forename: Adolf W
authors.initials: AW
authors.lastname: Lohmann