Snell's Law

Law of refraction linking the sines of the incidence and transmission angles to the refractive indices of the two media.

Specifications & Metrics

symbol

n₁ sin θ₁ = n₂ sin θ₂

Core Principles & Analysis

• The law was first discovered by the Persian scientist Ibn Sahl at the Baghdad court in 984, in the manuscript On Burning Mirrors and Lenses.
• In 1621 the Dutch astronomer Willebrord Snellius (1580–1626) derived a mathematically equivalent form but never published it.
• Beyond a critical angle the light is completely reflected by the boundary, a phenomenon known as total internal reflection.

Sources

• Wikipedia: Snell's law