Fresnel on lighthouse lenses. 19th-century diagrams produced by French physicist Augustin Jean Fresnel (1788-1827) as part of his work on lighthouse l

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Fresnel on lighthouse lenses. 19th-century diagrams produced by French physicist Augustin Jean Fresnel (1788-1827) as part of his work on lighthouse lenses. Fresnel studied optics and diffraction. He developed a type of lens (the Fresnel lens) for use in lighthouses. A Fresnel lens allows greater projection of light than can be achieved with mirrors. These diagrams, showing lenticular lenses used in lighthouses, are from a posthumous collection of his works: 'Oeuvres completes d'Augustin Fresnel' (1870).

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Photo credit: © KING'S COLLEGE LONDON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
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