While playing around with some laser diodes I have at home ~(405, 550, 650 nm) I have noticed that the refracted angles through some mediums (all?) is different.(adsbygoogle = window.adsbygoogle || []).push({});

That is, if I fire my 405nm laser through some water at [itex]\theta_{1}[/itex]=80°, the angle of refraction is ~[itex]\theta_{2}[/itex]=47.01±0.05°.

Now, if I fire my 550nm laser through the same water, at [itex]\theta_{1}[/itex], the angle of refraction is ~[itex]\theta_{3}[/itex]=47.30±0.05°.

And, finally, if I fire my 650nm laser through the same water, at [itex]\theta_{1}[/itex], the angle of refraction is ~[itex]\theta_{4}[/itex]=47.50±0.05°.

So, basically, all I know about refraction is snells law: [itex]n_{1}/n_{2}=Sin\theta_{2}/Sin\theta_{1}[/itex]. I don't really know how to mathematically find the relationship between wavelength and refraction.

I googled a bit and didn't see anything that popped out immediately to me. Aside from v=c/n => n = c/v => n = c/(fλ), and that what I'm dealing with here may be "dispersion."

So, is there a relationship here?Is there a relatively simple way for me to relate the angle refracted, wavelength, and the index of refraction of a medium?

How would I predict the angle refracted through a medium at a specific wavelength of light?Is it possible with such little information?

Could I say n = c/(λf) where c and f are fixed (what value do I use for frequency? Or is this specified on my diode?)

(My physics experienced ended with 2nd year physics, and we didn't spend too much time of refraction or optics.)

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# Relationship between wavelength and refraction

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