Brewster's Law
The law stating that reflected light is 100% linearly polarized when the angle of incidence equals the polarizing angle, where reflected and refracted rays are perpendicular.
Governing formula
tan θ_p = n2 / n1
SI unit
Degrees (°)
In depth
At Brewster's angle $θ_p$, electric field dipole oscillations in the medium parallel to the plane of incidence cannot radiate into the reflected ray direction, eliminating p-polarized reflected light.
Examples in the real world
Polarized sunglasses reducing glare from sunlight reflecting off wet roads or lake surfaces.