The Fresnel light fixture is actually named after its peculiar lens. The Fresnel lens is a succession of concentric rings, each one made up of a single lens. These are assembled in a symmetrical relationship on a flat surface to provide a short focal length. The first of these lenses, developed in 1748, were valued for being relatively light in weight and used with candles on ships. But they really became popular starting in 1821, when a guy named Augustin-Jean Fresnel started installing them in lighthouses.
—Nook Schoenfeld
