In
optics, dispersion is the phenomenon that the
phase velocity of a wave depends on its frequency. In a prism, dispersion causes the spatial separation of a white light into spectral components of different
wavelengths. Dispersion is most often described in
light waves, but it may happen to any kind of wave that interacts with a medium or can be confined to a
waveguide, such as
sound waves. Dispersion is sometimes called chromatic dispersion to emphasize its wavelength-dependent nature.
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