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Encyclopedia > Lens lantern

A lens lantern is a small, self-contained lamp structure which may sometimes be used to serve as a lighthouse. Unlike a regular Fresnel lens, the lantern requires no housing to protect it from the weather; its glass sides would refract and magnify the light in the same fashion as would the lens. Lens lanterns were popular alternatives to lighthouses in the nineteenth century; they required less care, were cheaper to erect, and could be fairly easily placed. A HDR image of a traditional lighthouse For other uses, see Lighthouse (disambiguation). ... Fresnel Lens displayed in the Musée national de la marine in Paris, France A Fresnel lens is a type of lens invented by Augustin-Jean Fresnel (pronounced fre-NELL in scientific and lighting applications, although often incorrectly pronounced FREZ-nell). ... The straw seems to be broken, due to refraction of light as it emerges into the air. ...

See also

  • F. Ross Holland, Jr. America's Lighthouses: Their Illustrated History Since 1716.



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