Because multi-mode fiber has a larger core size than single-mode fiber, it supports more than one propagation mode; hence, it is limited by modal dispersion, while single mode is not. Modal dispersion is a distortion mechanism occurring in multimode fibers and other waveguides, in which the signal is spread in time because the propagation velocity of the optical signal is not the same for all modes. However, it exists even when chromatic dispersion disappears. In contrast, if. Dispersion remains an enduring challenge for the characterization of wavelength-dependent transmission through optical multimode fiber (MMF). As is common knowledge, light rays entering a fibre at various angles of incidence will follow.