Light going through glass to make a rainbow

[relativitydude]

Someone in a physics class here proposed, a white light beam going through a meter worth of glass and because different frequences refract at different angles, a 1 cm rainbow would come out the other end. The only way I see this to be possible is for the beam to be infinetely thin. I mean REALLY THIN.

(He even says a 1mm beam would be thin enough to product a rainbow affect)

I think, however, even a beam of one micrometer the light would overlay back into white light because the vast number of points where the light strikes the glass.

 

[relativitydude]

No one know? :(

 

[Claude Bile]

The width of the rainbow would depend on the chromatic dispersion of the glass more than anything.

Claude.

 

[relativitydude]

What is this chromatic dispersion?

 

[Dr Transport]

Chromatic dispersion is where the index of refraction of the material depends on the wave length of the light, i.e. it is not a constant. Most materials index of refration depends on wavelength, so you will see a rainbow effect.