Refractive Index: Methods for Determining Beyond Newton's Rings

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Various methods exist for determining the refractive index beyond Newton's Rings, including measuring angles of incident and refracted beams. Total internal reflection (TIR) provides the most sensitive measurements through critical angle assessment. For small homogeneous particles, Mie scattering can be used, though it lacks the accuracy of TIR. Brewster's Angle is another technique that allows for measuring the refractive index of opaque objects. Interferometry can also be employed to compare the path lengths of coherent waves in different media, similar to the principles behind Newton's Rings.
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So, I was in my Undergraduate Labs yesterday, using Newton's Rings to determine the Refractive index of water. I was just wondering, other than measuring the angles of incident and refracted beams, if there were many other methods to determine refractive index?
 
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The most sensitive measurements, AFAIK, use total internal reflection (critical angle measurement).

For small homogeneous particles, the refractive index can be measured via scattering (Mie scattering), but the accuracy is not as good as TIR.
 
You might also look up "Brewster's Angle". This even let's you measure the index of refraction of opaque objects.
 
You can use an interferometer to compare the distance a coherent wave goes in air (or ieally vacuum) with one going through an other medium and see how they add up - this is essentially what Newton's rings is doing.
 
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