Patent ID: 6839481

Claim:
Multimode, optical fiber, local area network system including transmitter means, receiver means, and a transmission line, the transmitter means performing functions including generating optical signal and modulating such signal for introduction into the transmission line, the signal being at system wavelength within the wavelength range of 770-1700 nm, CHARACTERIZED IN THAT the said transmission line includes at least one fiber span comprising “Enhanced Multimode Fiber” (“EMF”), said EMF having a core that is: of profiled index-of-refraction for lessening difference in group velocity for supported modes, and said EMF also being provided both: with a longitudinally-spaced series of perturbations for promoting mode coupling as among bound modes, thereby further lessening mode dispersion; and with a radially-positioned core discontinuity in index-of-refraction for discouraging mode coupling between bound and cladding modes, thereby lessening added loss associated with the series of perturbations, and in that the said signal, as introduced into the said EMF, includes two “extreme” channel signals of differing wavelengths spaced by at least 25 nm.