Patent ID: 8891917
Filing Date: 2014-11-18
Classification: G02B,H01S

Abstract:
1. Transverse mode filter in an optical waveguide, wherein the filter is comprised of a Fabry-Perot cavity integrated into the optical waveguide, the Fabry-Perot cavity comprising two reflective elements situated at a distance from one another, wherein the reflective elements are waveguide Bragg gratings, wherein the wavelength of at least one mode of the optical waveguide differs from the resonant wavelengths of the Fabry-Perot cavity, whereas the wavelength of at least a second mode of the optical waveguide mainly coincides with a resonant wavelength of the Fabry-Perot cavity, wherein the optical waveguide is a light-conducting fiber having a fiber core, and wherein the waveguide is modified in the region of the Fabry-Perot cavity and/or in the region of the reflective elements in relation to the remaining regions of the waveguide, the modification being effected by the fiber core within the Fabry-Perot cavity and/or in the region of at least one of the reflective elements having a refractive index variation running transversally to the wavequide axis, whereas the index variation causes a mode-dependent variation of the optical path length within the fiber core.