Malus, Étienne Louis (1775–1812)
Étienne Malus was a French physicist who, in 1809, announced his discovery of the polarization of light by reflection. In 1810 Malus also produced a theory of double
refraction of light in crystals. Earlier in his career, in 1798, he
had taken part in the invasion of Egypt as a member of the engineer corps
in the army of Napoleon I.