# Refraction index vs. wavelength?

1. Dec 1, 2008

### jaejoon89

How does the refraction index vary with wavelength?

For example, if you take light that initially has just one wavelength and disperse it through a prism and calculate the different indices for each wavelength. I'm guessing they'll be different... Is it linear? exponential? etc.

2. Dec 1, 2008

### horatio89

I'm not sure of the exact physics defining the relationship between the refractive index and the wavelength, but there is an empirical formula relating these two variables known as Cauchy's Formula:

n = A + B/(lambda)^2, where A and B are constants, n is the refractive index at wavelength, lambda.