| | Encyclopedia: Fresnel lens (Site not responding. Last check: 2007-10-19) |
 | | Originally developed for lighthouses, the design enables the construction of lenses of large size and short focal length without the weight and volume of material which would be required in a lens of conventional design. |
 | | Jump to: navigation, search The Peggys Point lighthouse in Nova Scotia, Canada An aid for navigation and pilotage at sea, a lighthouse is a tower building or framework sending out light from a system of lamps and lenses or, in older times, from a fire. |
 | | Lighthouse Fresnel lens systems typically include extra annular prismatic elements, arrayed in faceted domes above and below the central planar Fresnel, in order to catch all light emitted from the light source. |
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