Refraction
General Description
Refraction is the word used to describe the phenomenon of a change in the direction an electromagnetic wave travels in.[1] Electromagnetic radiation (which includes light) is observed to change direction when it's velocity changes. How much the velocity differs from the velocity in a vacuum is commonly called the refractive index. The vacuum value is set to 1 for all wavelengths of electromagnetic radiation.
This property of a medium has a few different names.
| NAME |
|---|
| Index of Refraction |
| Refractive Index |
| Optical Density |
| Relative permittivity and permeability |
Mechanisms of Refraction
It is commonly believed that the absolute value of the refractive index is what causes electromagnetic radiation to bend. This is an incorrect view. it is the relative refractive index along an arbitrary path that determines a change of direction.
