Refraction of white light by prism using arc lamp.

Refraction of white light by prism using arc lamp. Carbon Arc Lens Lens Prism Optical Bench Adjustable Slit Collimated white light is sent through an adjustable slit and then through the edge of an equilateral prism. The light is refracted (first upon entering the prism and then upon leaving it), and the spectrum is focused on a projection screen. The prism is vertically mounted on a .5" rod which may be rotated about its axis to show the angle of minimum deviation. Red light is refracted the least. Violet light is refracted the most. The angular spread of all the colors is called dispersion. There are various prisms with different indices of refraction: quartz, flint-glass, Lucite, etc.