Dispersion of Waves

Dispersion of Waves

 

the dependence of the phase velocity of harmonic waves on their frequency. Dispersion is determined by the physical properties of the medium through which the waves are propagating. For example, in a vacuum, electromagnetic waves propagate without dispersion; however, in a material medium, even one as rarefied as the earth’s ionosphere, wave dispersion arises. Ultrasonic waves also exhibit dispersion.

The existence of wave dispersion causes distortion of signals propagated through the medium, since the harmonic waves of various frequencies into which the signal may be broken down propagate at various velocities. The dispersion of light propagating through a transparent prism results in the resolution of white light into a spectrum.