Abstract: Improved optical mode mixers for use in conjunction with optical fibers and devices incorporating optical fibers are disclosed and claimed. The optical mode mixers are formed from a coherent, orderly bundle of numerous small diameter optical fibers in a longitudinally aligned, parallel array. The mode mixer is optically linked to the fiber optic cable and effectively reduces undesirable high order modes of light transmission while eliminating alignment sensitivity. The coherent fiber optic bundles may be as short as ten wavelengths of light in length and will have a diameter substantially equal to that of the fiber optic cable to which they are coupled.