Multimode fiber gradually
Unlike step-index fibers, graded-index multimode fibers have a refractive index that decreases gradually from the core center towards the core-cladding interface. Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. Multimode fibers are fibers having multiple guided modes at the operating wavelength — sometimes only a few (→ few-mode fibers), but often many. This carefully engineered index contrast confines light within the core through total internal reflection, enabling optical signals to travel with. Although they can do the same job in some instances, the different construction methods make each of them better suited to certain tasks and budgets.
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