FRESNEL, AUGUSTIN-JEAN

born May 10, 1788, Broglie, Fr. died July 14, 1827, Ville-d'Avray French physicist who pioneered in optics and did much to establish the wave theory of light advanced by Thomas Young. Fresnel served as an engineer in various departments of France but lost his post temporarily during the period following Napoleon's return from Elba (1814). About that time he seems to have begun his researches in optics. He studied the aberration of light, created various devices for producing interference fringes, and, by applying mathematical analysis to his work, removed a number of objections to the wave theory. With Franois Arago he studied the laws of the interference of polarized light. He obtained circularly polarized light and developed the use of compound lenses instead of mirrors for lighthouses. Although his work in optics received scant public recognition during his lifetime, Fresnel maintained that not even acclaim from distinguished colleagues could compare with the pleasure of discovering a theoretical truth or confirming a calculation experimentally.