Explanation
In optical fiber, many electromagnetic modes can be transmitted. Different electromagnetic modes of optical fiber are transmitted at different speeds, and the time to reach the receiving end is different. This time difference is called group delay. It is much larger than the dispersion of single mode optical filler. Group delay causes optical information pulse broadening, thus limiting the improvement of transmission information rate of multimode optical fiber. In order to improve the transmission rate of multimode optical fiber, the waveguide structure with parabolic refractive index profile is adopted.
Classification
Information materials -> Optical dielectric materials -> Optical dielectric materials