Hyperradiant Fresnel lens

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the lantern of Makapuu Point Light, showing the hyperradiant lens within; note the men on the gallery

Hyperradiant fresnel lenses are fresnel lenses larger than "first order" lenses, so they are larger than 12 feet (3.7 m) tall and 6 feet (1.8 m) across, with a focal length larger than 36 inches (0.91 m).

The Hyperradiant fresnel lenses were the largest ever built and were installed in fewer than a dozen major "landfall" beacons around the world. Other recipients include Makapu'u Point lighthouse on Oahu Island in Hawaii, Cabo de São Vicente in Portugal, Manora Point in Karachi, Pakistan, the famous Bishop Rock off the coast of Cornwall (in the UK), Abrolhos island off the coast of Brazil and Cape Race, Newfoundland. By the 1920s, high-intensity lamp technology had rendered lenses of this size obsolete.

[edit] External links

• Makapuu Point

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