Question

what is the theory of prism​

Answer 1

An optical prism is a transparent optical element with flat, polished surfaces that refract light. At least one surface must be angled—elements with two parallel surfaces are not prisms. ... A dispersive prism can be used to break white light up into its constituent spectral colors (the colors of the rainbow).

Answer 2

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An optical prism is a transparent optical element with flat, polished surfaces that refract light. At least one surface must be angled—elements with two parallel surfaces are not prisms. ... A dispersive prism can be used to break white light up into its constituent spectral colors (the colors of the rainbow).