What is Prism (optics)?
{{redirect|Prism}} [[File:Prism-rainbow.svg|thumb|Drawing of a prism bending light]] [[File:WhereRainbowRises.jpg|right|128px|thumb|The glowing, colored strips are a rainbow.]] A '''prism''' is a special piece of [[glass]], [[crystal]], or [[plastic]] that bends light. The light bends (or ''refracts'') because it moves slower in the glass, crystal or plastic than it does in [[air]]. If different [[color]]s of light move at different speeds, each color bends a different amount. This is [[dispersion]] and it splits the light into a band of different colors called a [[spectrum]]. This spectrum has the same colors as a [[rainbow]] does, because rainbows are made the same way, by bending light. They happen when light is bent by tiny drops of water floating in the air. If the light does not come out when you shine it into the prism, it is called internal reflection. Some prisms are used to disperse light. Binoculars also use prisms, to reflect light. This lets the tubes of the [[binoculars]] be short. Some [[camera]]s use a prism to send light to the [[viewfinder]], so the [[photographer]] can see what will be [[photograph]]ed. {{science-stub}} [[Category:Optics]]