Mode dispersion analysis based on refractive index of graded-index multimode fiber

In this paper, an analysis method for mode dispersion of optical fiber is proposed, which combines the digital holographic microscopic tomography and the ray tracing theory. Based on ray tracing theory, a simulation of multimode fiber transmission is implemented, and the transmission characteristics of both perfect and defective optical fibers are analyzed. Based on digital holography, the refractive index of multi-mode fiber OM2 and OM4 is measured by the refractive index of optical fiber testing system. The transmission analysis in view of measured refractive index is performed,the mode delay and transmission characteristics are obtained.