N1-21
Show how a prism can recombine previously dispersed white light.
The prismatic spectrum setup of demonstration N1-01: PRISMATIC SPECTRUM OF WHITE LIGHT - POINT SOURCE is used to create a white light prism spectrum, seen in the photograph in the center. A second identical prism is then positioned in the beam with the base opposite that of the dispersing prism, so that the colors are recombined into a white spot.
OM1, LS1

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