Dispersion by a Prism

Ray Tuck
Dispersion is the spreading out of light into its colours. Dispersion in a prism occurs because the refractive indicies of many materials (including glass, perspex and water) depend on the colour (wavelength) of the light.
  • White light is incident on a 60°, 60°, 60° prism. Use the slider to change the initial angle of incidence.
  • You can set the refractive index for red light (nr) and the difference in indicies for red and blue light (nb-nr).
  • The angle of dispersion is the angle between the red and blue rays after they have refracted through the prism.
  • The angle of deviation is the angle between the line of the incident ray and the final refracted red ray.