The diagram shows refraction of light passing into ... at the boundary between glass and air as it leaves the prism. When white light passes through a prism it can be split up into its colours.

This explains why a prism can disperse white light into different colours. The change in refraction is quite small and is only significant for some geometries. A ray of light is incident on the ...

The important property of prisms in this article is their ability to redirect light through refraction and reflection. A collection of deck lights used to direct sunlight below deck in ships.