# Definition of Snell's law in English:

## Snell's law

### noun

Physics
• A law stating that the ratio of the sines of the angles of incidence and refraction of a wave are constant when it passes between two given media.

• ‘Fermat proposed that light follows the path which takes the shortest time, enabling Snell's law of refraction to be deduced mathematically.’
• ‘In bi-directional transmission distribution functions it is also necessary to include refraction, which is described by Snell's law.’
• ‘The largest angle allowed in the photoresist film is inversely related to its refractive index, as calculated using Snell's law and assuming a 90° half angle in air.’
• ‘One might imagine that an experimental determination of Snell's law would be a simple matter.’
• ‘This was developed with ray diagrams and key formulae such as Snell's law and the lens equation.’

### Origin

Late 19th century named after Willebrord van Roijen Snell (1591–1626), Dutch mathematician.

## Snell's law

/ˈsnelz ˌlô/ /ˈsnɛlz ˌlɔ/