Alfred Cornu

Marie Alfred Cornu was a French physicist and professor at the École polytechnique, born at Orléans on 6 March 1841. The Cornu spiral, a graphical device for computing light intensities in Fresnels model of near-field diffraction and also used in the geometric design of roads, is named after him, as is the Cornu depolarizer. He was educated at the École polytechnique and the École des mines and in 1867 succeeded Émile Verdet as professor of experimental physics at the École polytechnique, where he remained throughout his life. His original work was mainly concerned with optics and spectroscopy, and he improved Fizeaus method of measuring the speed of light, which won him the prix Lacaze in 1878, membership of the French Academy of Sciences and the Rumford Medal of the Royal Society. He was president of the French Academy of Sciences in 1896 and died at Romorantin on 12 April 1902.