Fresnel lens

Lighthouse technology changed dramatically as a result of the pioneering work of Augustin Jean Fresnel (French, 1788–1827), a physicist who studied and experimented with light reflection and refraction. In 1822, he succeeded in designing a lens that utilized several lenses and dozens of prisms to create a unified and far-reaching beam that was visible 20 miles further than previous lights. The first Fresnel lighthouse lens employed in America was installed in 1841. There are seven orders or sizes of Fresnel lenses. The Fourth Order was used in major harbor lights, and it is the most commonly used size in lighthouses on the Great Lakes. This lens was never put into service, and it was most likely a sales model. Early Fresnel lenses were made primarily in France, but in the 1890s, the American glassmaker George Macbeth became interested in producing optical glass. His initial attempts were unsuccessful, but he continued his investigations after the merger that created the Macbeth-Evans glass company in 1899. In 1910, the United States Lighthouse Bureau asked Macbeth-Evans to consider the production of Fresnel lenses, since they were already experimenting with optical glass. Macbeth-Evans succeeded in making the lenses in 1912, but only a limited number were produced. The Fresnel lens was a crucial scientific development in glass and in lighting that allowed for much safer water travel and the expansion of commercial shipping in a period of great industry. With the advent of newer technologies, lighthouses and their Fresnel lenses have lost their usefulness, and many have disappeared or have been destroyed as lighthouses around the world are decommissioned.