Sunday, July 23, 2017 from 3:00 PM to 5:00 PM EDT
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National Lighthouse Museum 
200 The Promenade at Lighthouse Point
Staten Island, NY 10301


National Lighthouse Museum 


The Introduction of the Fresnel Lens into the USLHE 

first order Fresnel lens In 1821, after several years of studying the properties of light in his spare time, Augustin Fresnel, a French civil engineer working for the state’s department of bridges and roads, developed a lighthouse lens that now bears his name. The Fresnel lens concentrates light into a brighter beam by capturing more than 80% of the escaping light through the precise arrangement of the glass discs and prisms that make up the larger lens. This concentration into a brighter beam of light allowed the light to be projected further out to sea for the aid of commerce and navigation.

The Fresnel lens was, arguably, the most important development of
lighthouse technology, between the erection of the Pharos of
Alexandria, and the introduction of electricity in 1875. If you’ve
been to the museum at Navesink Twin Lights, you’ve seen the first
Fresnel lens every used in the United States.

James Risk, a doctoral candidate for his studies of the history of
Fresnel lenses, will discuss the introduction of different kinds of
lens technology in the United States and in other parts of the world.