A theoretical analysis shows that the effect occurs in both single-mode and multimode fibers and depends on fiber end face separation, the source spectrum, and the modal power distribution in the fiber. 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. Multi-mode fiber has a fairly large core diameter that enables multiple light modes to be. Multimode fibers are fibers having multiple guided modes at the operating wavelength — sometimes only a few (→ few-mode fibers), but often many. This is made possible by its relatively large core diameter, typically 50 or 62. 5 microns, compared to the ~9-micron core in single-mode fiber. (Basically, what we have just described is wavelength division.
[pdf] 