Polarization & rainbows

About plane polarization & rainbows
  • Plane polarization is one of the optical effects that account for the appearance of rainbows.
  • Plane polarization, also known as linear polarization, is a characteristic of electromagnetic waves, including light.
  • The polarization of light in rainbows contributes to the vividness and intensity of the colours we see.
  • The light that produces rainbow effects is typically 96% polarized. This means that:
    • Observed light exiting a raindrop is polarized on a plane bisecting each droplet and tangential to the arcs of the rainbow.
  • The presence of other atmospheric phenomena, such as water droplets of varying sizes or ice crystals, can affect the amount of plane polarization and so influence the appearance of rainbows.

Rainbows, raindrops & angles

About rainbows, raindrops & angles
How they interconnect
    • In any particular example of a ray of light passing through a raindrop, the angle of deviation and the angle of deflection are directly related to one another and together add up to 1800.
    • The angle of deviation is always equal to 1800 minus the angle of deflection. So clearly the angle of deflection is always equal to 1800 minus the angle of deviation.
    • In any particular example, the angle of deflection is always the same as the viewing angle because the incident rays of light that form a rainbow are all approaching on a trajectory running parallel to the rainbow axis.