FRESNEL, AUGUSTIN JEAN French physicist, was born at Broglie, Normandy, on May 10, 1788. He was educated at the Ecole Centrale in Caen, the Ecole Polytech nique, and finally went to the Ecole des Fonts et Chaussees. He served as an engineer in several departments, but lost his appoint ment in 1814 because he opposed Napoleon's return from Elba. On the second restoration he obtained a post as engineer in Paris. His researches in optics appear to have been begun about 1814, when he prepared a paper on the aberration of light (q.v.), which, however, was not published. Fresnel's work on interference did a great deal to establish the wave theory of light. (See LIGHT : The Age of Fresnel) ; and various devices for producing interference fringes bear his name. He applied mathematical analysis to his work and removed a number of objections to the wave theory. With D. F. J. Arago he studied the laws of the interference of polarized rays. Circularly polarized light he obtained by means of a rhomb of glass, known as "Fresnel's rhomb." He was a pioneer in the use of compound lenses instead of mirrors for lighthouses. He was a member of the Academie des Sciences, and a foreign member of the Royal Society. He died at Ville-d'Avray, near Paris, on July 14, 1827.
He was a member of the Academie des Sciences and the Royal Society, but his labours in the cause of optical science received during his lifetime only scant public recognition, and some of his papers were not printed by the Academie till many years after his decease. But, as he wrote to Thomas Young, the English scientist, in him "that sensibility, or that vanity, which people call love of glory" had been blasted. "All the compliments," he says, "that I have received from Arago, Laplace and Biot never gave me so much pleasure as the discovery of a theoretic truth, or the confirmation of a calculation by experiment." See A. Duleau "Notice sur Fresnel" in Revue Encyclopedique (vol. xxxix., 1828) ; D. F. G. Arago, Oeuvres completes, vol. i. (17 vols., 1854-62) ; G. Peacock, Miscellaneous works of Thomas Young, vol. i. (3 vols., 1855).