Charles Fabry

Born on 11 June 1867 in Marseille, France, Charles Fabry was a physicist who, working with other French scientists, developed a theory of multibeam interference and discovered the ozone layer. Fabry graduated from the University of Paris in 1892 and joined the Marseilles University staff in 1894. He quickly revolutionized the fields of optics and spectroscopy by developing the Fabry–Pérot interferometer alongside Alfred Pérot. The duo based the interferometer, or elaton, on Fabry’s theories of multibeam interference. Versions of the device are still used today in high-definition spectroscopy. Later Fabry, along with Henri Buisson, discovered the ozone layer in Earth’s atmosphere by deducing that the molecule was responsible for absorbing UV radiation from the Sun. In 1921 Fabry took a professorship at the Sorbonne in Paris and became the first director at the city’s Institute of Optics. Some of Fabry’s awards include the Rumford Medal from the Royal Society in London in 1918, the Franklin Medal in the US in 1921, and an honorary appointment to the Optical Society in 1933. Fabry was a prolific author, writing popular articles in addition to scientific ones so that laypeople could understand his work. At the end of his life, Fabry assisted French scientists in World War II. His poor heath near the end of the war forced him back to Paris, where he died at age 78 in 1945. (Photo credit: AIP Emilio Segrè Visual Archives, E. Scott Barr Collection)

Date in History: 11 June 1867