Mode Dispersion in Graded-Index Optical Fiber with Near Parabolic-Index Profiles

The propagation constants and the group delay time of the guided modes in the graded-index fiber with near parabolic-index profiles can be determined in almost analytic form within the WKBJ approximation. The minimum mode dispersion in this fiber can be attained by correcting the fourth order term to the square law profile after the refractive-index of the cladding can be adjusted.