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Glass for lighthouses |
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Augustine-Jean Fresnel (1788-1827) | © Science and Society Picture Library
In 1822 French engineer Augustine-Jean Fresnel introduced a revolutionary lens that dramatically improved lighthouse illumination.
Fresnel replaced multi-lamps and reflectors with a single lamp placed at the centre, or focal plane, of the lens. The beehive-shaped lens had a central panel of magnifying glasses surrounded by concentric rings of prisms and mirrors. These were angled to gather light and direct it towards the focal plane, where it was intensified and projected seaward.
Fresnel’s lens was quickly adopted by the maritime world Eventually, all the world's lighthouses were equipped by Fresnel’s lenses. BACK to story |
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What is a Fresnel’s lens? | |  |
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