FRESNEL, in 1820, devised and constructed a lens for first order lights of 920 mm. radius. It was composed of a plano-convex lens, with five refracting prisms concentric with it, and four segments of rings in the corners all gradually decreasing in breadth as they receded from the centre. The separate pieces of which these lenses were made up were cemented together and mounted in metallic frames 30 inches square.
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STEVENSON, C. Note on the Progress of the Dioptric Lens as Used in Lighthouse Illumination. Nature 46, 514–516 (1892) doi:10.1038/046514e0