Fresnel, Augustin

Fresnel, Augustin Jean (1788—1827). A French physicist noted for his work on optics, such as aberration of light, interference, wave theory of light, etc. He constructed the first practical "interferometer", which is used at present in modified form in Ordnance, such as "interferometric analysis of air flow about projectiles In free flight"... 

The conversion came at a time when the Newtonian program of explanation had lost ground in several fields of laboratory studies, including physical optics, electricity, and heat. Intellectually, this loss of influence was epitomized by the publication in 1826 of Augustin Fresnel s 1819 prize memoir on the diffraction of light, in which he abandoned the Newtonian corpuscular theory. Institutionally, the decline was registered by the 1822 election of Fourier to the office of permanent secretary of the Academy of Sciences, despite the opposition of Laplace, who along with Berthollet had earlier personified the Newtonian tradition in France.37... 

Fresnel, A. J. Supplement au deuxieme memoire sur la diffraction de la lumiere. Presente a I Academie des Sciences dans la seance du 15 juillet 1816. [Supplement to the second paper on the diffraction of light.] In (Evres Completes d Augustin Fresnel. (Eds., de Senarmont, H., Verdet, E. and Fresnel, L.) Vol. 1., pp. 129-170. Imprimerie Imperiale Paris (1866). 

The suggestion that the optical activity of quartz crystals might be associated with some property of the molecules was made as early as 1824 by Augustin Fresnel. 

Thomas Young s in 1803 performed for the first time the classic experiment that demonstrates optical interference the two-slit interference experiment, which appears as an example in many books on optics in order to explain the concept of interference. Young was not the first to report the phenomenon. It had been observed in various forms, such as Newton s rings, Brewster interference, and Michelson interferometer. Young s experiments however mark a point in the history of science. They led the way to the studies of Augustin Fresnel (1816), who introduced the measurement of the wavelength of light and established... 

Augustin Fresnel (1788-1827) French physicist Paris, France. 

In 1813 Jean Baptiste Biot (1774-1862) had discovered that quartz crystals could rotate the plane of plane-polarised light, and two years later he found that the same property was displayed by various natural organic products such as the liquids oil of turpentine and oil of lemon, and also by a solution of camphor in ethanol. This property, known as optical activity was found to disappear in the case of quartz when the crystals were fused. Augustin Jean Fresnel (1788-1827) suggested that the optical activity of the quartz was due to a helical arrangement of the molecules in the crystal, but it was evident that when the property was displayed by substances in the liquid or solution phase the explanation must reside in the structure of the molecule itself. 

THALES Research Technology 1, av Augustin Fresnel, F-91767 PALAISEAU Cedex laurent.riouxOthalesgroup.com Intecs S.p.A. 

This can be re-expressed in terms of the incident intensity, /<, and the reflectivity of the soap film, is the fraction of the incident intensity reflected by the soap film and depends on the angle of incidence and the refractive index of the film. It can be obtained from classical electromagnetic theory and was first derived by Augustin Jean Fresnel in 1823. Expressing (2.24) in terms of and /i,... 

---