The refractive index (index of refraction) of a medium measures how much the speed of light is reduced when it passes through a medium compared to its speed in a vacuum.
- Refractive index (or, index of refraction) is a measurement of how much the speed of light is reduced when it passes through a medium compared to the speed of light in a vacuum.
- The concept of refractive index applies to the full electromagnetic spectrum, from gamma-rays to radio waves.
- The refractive index can vary with the wavelength of the light being refracted. This phenomenon is called dispersion, and it is what causes white light to split into its constituent colours when it passes through a prism.
- The refractive index of a material can be affected by various factors such as temperature, pressure, and density.