What causes rainbow effect on edge of sunglasses?

User Avatar
Wiki User
2008-11-13 18:34:04

Sunlight coming from the sun is known as white light - it

doesn't necessarily look white but maybe a better name would be

"neutral". White light is actually made up of many different colors

of light mixed together, just like you would mix paint colors

together to obtain a new color. Each color within white light has

it's own wavelength. Blue has a shorter wavelength than, say, red.

All the colors of the rainbow all lined up represent a slightly

different wavelength- like lining up all the children in a school

according to their height - tall at one end, short at the other. As

white light passes through things like glass, the ray of light is

bent when it passes from air into the glass, and again when it

passes from the glass back into the air on the other side. These

are called medium boundaries - boundaries between one medium (say

air) and another (say glass, or water). Each different color is

bent a different amount according to how long or short its

wavelength is. So as the light passes through the medium

boundaries, they filter each color into a slightly different path,

spreading them out to display on a wall or on your eye as a


Copyright © 2020 Multiply Media, LLC. All Rights Reserved. The material on this site can not be reproduced, distributed, transmitted, cached or otherwise used, except with prior written permission of Multiply.