Today is the birthday of Etienne Malus, born in 1775, he was a mathematician who studied geometric light. Being a mathematician, he also studied line geometry and line systems called ray systems. He used these ray systems to prove Christiaan Huygen’s theory of light. His theory of double refraction of light in crystals was published in 1810. He is probably best known for Malus’ Law giving the resultant intensity, when a polarizer is placed in the path of an incident light beam.
Today is also the birthday of
Walter Schottky, born in 1886 who invented the screen-grid vacuum tube
And Vladimir Prelog, born in 1906 who is famous for the Cahn, Ingold, Prelog sequence used in organic chemistry to name stereoisomers with an R/S descriptor, or an E/Z descriptor for double bonds. He is the source of anecdotes about almost all eminent chemists and his scientific opus encompasses over 400 works.