Although there is no modal dispersion between different propagating modes, dispersion has not been completely eliminated. In fiber-optic communication, a single-mode optical fiber, also known as fundamental- or mono-mode, is an optical fiber designed to carry only a single mode of light - the transverse mode. However, pulse broadening does not disappear altogether. Other names for this phenomenon include multimode distortion, multimode. Optical Fiber: An optical fiber is a lightweight, thin, and flexible electrical conductive material made of a glass or plastic material that is principally designed for data transfer in telecommunications networks. Material dispersion stems from the frequency dependence of the index of.