Refraction of light

Refraction of light is a fascinating phenomenon that occurs when a light beam passes from one medium into another. When this event takes place, the light beam is refracted, which means that its direction changes. The angle of incidence plays a decisive role here - that is the angle between the incident light beam and an imaginary line perpendicular to the interface between the two media. Equally important is the angle of refraction, which describes the angle between the refracted light beam and this imaginary line.

To describe this phenomenon, we use the refractive index, which is also known as the index of refraction. This dimensionless quantity indicates how strongly light is refracted in a particular medium compared with its value in a vacuum.