Ridley was the first to successfully implant an intraocular lens on 29 November 1949, at St Thomas' Hospital at London. That lens was manufactured by the Rayner company of Brighton, East Sussex, England from Perspex CQ polymethylmethacrylate (PMMA) made by ICI (Imperial Chemical Industries). It is said the idea of implanting an intraocular lens came to him after an intern asked him why he was not replacing the lens he had removed during cataract surgery. The acrylic plastic material was chosen because Ridley noticed it was inert after seeing RAF (Royal Air Force) pilots of World War II with pieces of shattered canopies in their eyes (this acrylic resin is known by several trade names including Lucite and Plexiglas). The intraocular lens did not find widespread acceptance in cataract surgery until the 1970s, when further developments in lens design and surgical techniques had come about. As of the early 2000s, more than a million IOLs were implanted annually in the United States. That number was estimated by the World Health Organization to have increased to 20 million annually worldwide by 2010 (for cataract surgery), and has projected increased IOL surgeries to reach 32 million worldwide by 2020. See also References Further reading Xia T, Martinez CE, Tsai LM. Update on Intraocular Lens Formulas and Calculations. Asia Pac J Ophthalmol (Phila). 2020 May-Jun;9(3):186-193. doi: 10.1097/APO.0000000000000293. PMID: 32501896; PMCID: PMC7299214. Corrective lenses Eye Implants (medicine) Ophthalmology Vision