Dispersion types of fibers

1. Material dispersion refers to the pulse broadening, which is a result of the phenomenon that the refractive index of fiber material varies according to the light source frequency and different light source frequencies are propagated at different group velocities.
2. Waveguide dispersion is due to the modular propagation constant changes based on wavelengths. It is related to the fiber waveguide structure parameters and the waveguide dispersion values are similar to material dispersion values. Material dispersion and waveguide dispersion are present in both single-mode fibers and multi-mode fibers.
3. Modal dispersion refers to the pulse broadening, which is a result of the phenomenon that the group velocities of the same light source frequency in different transmission modes are different. Modal dispersion mainly exists in multi-mode fibers.
In a word, both material dispersion and waveguide dispersion are caused by different frequencies of transmission signals in a fiber; modal dispersion is caused by different modes of transmission signals in a fiber.

Scroll to top