title: The Offner imaging spectrometer in quadrature.
abstract: This is a proposal and description of a new configuration for an Offner imaging spectrometer based on the theory of aberrations of off-plane classical-ruled spherical diffraction gratings. This new spectrometer comprises a concave mirror used in double reflection and a convex reflection grating operating in quadrature, in a concentric layout. A very simple procedure obtains designs that are anastigmatic for a given point on the entrance slit and a given wavelength. Specific examples show that the performance of this type of system improves the performance of analogous conventional in-plane systems, when compactness and/or high spectral resolution is of fundamental importance.
authors.affiliation: Departamento de Física Aplicada, Escola Universitaria de Optica e Optometría, Universidade de Santiago de Compostela, 15782 Galicia, Spain.
authors.forename: Xesús
authors.initials: X
authors.lastname: Prieto-Blanco
authors.forename: Carlos
authors.initials: C
authors.lastname: Montero-Orille
authors.forename: Héctor
authors.initials: H
authors.lastname: González-Nuñez
authors.forename: María Dolores
authors.initials: MD
authors.lastname: Mouriz
authors.forename: Elena López
authors.initials: EL
authors.lastname: Lago
authors.forename: Raúl
authors.initials: R
authors.lastname: de la Fuente