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Fresnel Lens
Item #HL631
A limited edition of 4,000.
In 1822, Augustine Fresnel, a French Physicist, invented a system of lenses and prisms that magnified and focused as much as 85% of the light from a single source. His invention was especially intended for use in lighthouses. He envisioned six 'orders' of lenses which he he ranked from first to sixth. (Later a three-and-a-half order was created.)
First order lenses were the largest - six feet in diameter and 18 feet high. These were used primarily as 'land-fall' lights, being visible from up to 24 miles at sea. Fourth, fifth and sixth order lenses were used on harbors, lakes and rivers.
Lenses were made in France, and later in England, and then shipped around the world where they were assembled atop tall towers.
While Fresnel's lenses were adopted quickly by European lighthouse authorities, it wasn't until 1855 that a Fresnel lens was fitted in an American lighthouse.
Over time, lenses were made to rotate with bulls-eye panels creating a flash. Colored panels or colored windows on the lantern room have been used to create distinct identifying patterns for different lighthouses.
Harbour Lights' reproduction of a fifth order beehive lens features a brass-plated metal frame with clear resin one-piece lens. The entire lens model may be rotated by hand by means of wheels that ride in a track in the wooden base.
Fresnel Lens Harbour Lights Accessories Item #HL631
A limited edition of 4,000.
In 1822, Augustine Fresnel, a French Physicist, invented a system of lenses and prisms that magnified and focused as much as 85% of the light
Price: $151.73
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