title: Focusing of light by zone plates in Selfoc gradient-index lenses.
abstract: We study the diffraction fields in a hybrid diffractive-gradient-index element composed of an amplitude zone plate and a quarter-pitch Selfoc gradient-index lens under uniform illumination. Focal positions of the diffractive orders and zone-plate diffraction efficiencies are measured, thereby validating the existing theoretical results.
authors.affiliation: GRIN Optics Group, Departamento de Física Aplicada, Escola de Optica e Optometría, Universidade de Santiago de Compostela, Campus Sur, E15782 Santiago de Compostela, Spain. moskeh@usc.es
authors.forename: José Manuel
authors.initials: JM
authors.lastname: Rivas-Moscoso
authors.forename: Daniel
authors.initials: D
authors.lastname: Nieto
authors.forename: Carlos
authors.initials: C
authors.lastname: Gómez-Reino
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Fernández-Pousa