This is called refraction. The frequency of light does not change as it refracts. The refractive index of a material is a measure of the change in the speed of light as it passes from a vacuum (or ...

This study examines interferometric techniques for distance measurement, focusing on innovations that mitigate air turbulence and refractive index fluctuations.

In all ray diagrams, all angles of incidence and refraction are measured between the ray and the normal. Watch this video for a practical demonstration of measuring the refractive index of glass.