Polarization of light by reflection (Malus' law)
Polarización de la luz por reflexión (ley de Malus)
- Date
- 1808 · confidence high
- Place
- Paris, France
- Credited to
- Étienne-Louis Malus; David Brewster
- People
- 👤 David Brewster1781–1868👤 Étienne-Louis Malus1775–1812
- Field
- Communication
What was discovered
Malus discovers, while looking at the sun's reflection in the windows of the Luxembourg Palace through a calcite crystal, that reflected light is polarised, and formulates the cosine-squared law. It reveals that light has a transverse orientation.
The double refraction of Iceland spar (Bartholin, Copenhagen, 1669) was the first observed manifestation of polarisation.
What it led to
- Light as a transverse wave (Fresnel, Young, 1817)
- Brewster's angle (1815)
- Polarimetry and optical crystallography
- LCD screens and polarised glasses
Built on
- Double refraction in Iceland spar (Bartholin)1669
- Bartholin's double refraction (1669)
- Huygens's explanation of calcite
Made possible
- Optical activity: rotation of the plane of polarization1811-1815
- Kaleidoscope1816
- Fresnel's wave theory of diffraction; transverse light waves1818
- Nicol prism1828
- Liquid-crystal display (LCD)1964-1971
- Polarimeter
- Polaroid filters (Land, 1929)
- Liquid crystal displays