Prosthetic eyes were an early innovation. The first artificial eyes were made from gold and silver and were described by Ambroise Paré in the 1500s. These were followed in the 1800s by a more realistic-looking eye made of enamel. These were expensive and broke easily, but fortunately the more durable glass eye appeared around 1835.
An ocularist would have a range of different eyes in stock, which would be tried on a patient to get the best fit. One of the most important innovations in artificial eyes was the development of plastic replacement eyes in 1942. These lasted longer than their enamel or glass counterparts and were much cheaper to produce.
The Ministry of Pensions Plastic Eye Unit was established to provide ex-servicemen who had lost an eye with a durable plastic replacement. This service was extended to all civilians with the establishment of the National Health Service in 1948. A working eye - as opposed to a prosthesis for appearance sake - sounds like the stuff of science fiction, but new developments mean that at some stage in the future this will be an option for some patients.
N Handley, `Artificial eyes and the artificialisation of the human face', in C Timmermann and J Anderson (eds), Devices and Designs: Medical Technologies in Historical Perspective (Basingstoke: Palgrave, 2006), pp 97-11
K Ott, `Hard wear and soft tissue: craft and commerce in artificial eyes', in Katherine Ott et al (eds), Artificial Parts, Practical Lives: Modern Histories of Prosthetics (New York: New York University Press, 2002), pp 147-170