Patent ID: 6400866
Filing Date: 2002-06-04
Classification: G02B

Abstract:
An optical system comprisingan optical transmitter, a utilization device and an optical fiber transmission path that optically couples said transmitter and said device, said transmission path comprising at least a section of microstructure optical fiber in which at least two transverse modes of optical radiation propagating in said fiber are decoupled from one another over the length of said section, and further including a first modulator for impressing information on a first optical signal propagating along said fiber in one of said transverse modes and a second modulator for impressing information on a second optical signal propagating along said fiber in another of said transverse modes, said microstructure fiber comprising a core region in which said optical radiation can propagate, an inner cladding region surrounding said core region and having an effective refractive index lower than that of said core region, an outer cladding region surrounding said inner cladding region, said inner cladding region including a multiplicity of features positioned circumferentially in at least one relatively thin layer around said core region, said features being effective to provide index guiding of said radiation, and said core region and said inner cladding region being mutually adapted so that said fiber exhibits decoupling of its transverse spatial modes at visible and near infrared wavelengths of said radiation, said core region having a diameter less than about 6 &mgr;m and the difference in effective refractive index between said core region and said inner cladding region being greater than about 10%.