Prism Dispersion: Does Light Diffraction Follow Thin Film Rules?

[stringbean]

Does dispersion of light by a prism have anything to do with how thin films disperse light of different colors at different angles? Could a person imagine the sides as if they were thin films?

 

[Meir Achuz]

Dispersion due to refraction by a prism and dispersion by interference between thin films are completely different, and have almost nothing to do with each other.
They are each wave phenomena, but with different mechanisms.

 

[Bob S]

One very significant difference is that for dispersion to occur in a prism, the index of refraction has to be wavelength dependent. Because of dispersion relations (Kramers-Kronig relations), there has to also be absorption in the prism. See
http://en.wikipedia.org/wiki/Kramers–Kronig_relation
Absorption is not required for reflection of different wavelengths (colors) from thin films at different angles.
Bob S