title: Azimuthal mode discrimination of annular resonators.
abstract: A diffraction formula for annular beam propagation is suggested. Significant computational savings are obtained without restriction to low azimuthal mode orders. Azimuthal mode discrimination is shown to exist in stable annular resonators. High-order azimuthal modes can suffer low diffraction losses with certain mirror parameters. These high-order modes are identified with azimuthal revolving rays that satisfy known geometric relations for multipass resonators.
authors.forename: D
authors.initials: D
authors.lastname: Ehrlichmann
authors.forename: U
authors.initials: U
authors.lastname: Habich
authors.forename: H D
authors.initials: HD
authors.lastname: Plum