A contact lens is a thin, curved lens placed on the film of tears that covers the surface of your eyes to correct vision.
Contact lenses are either hard or soft, depending on the material they are made.
Soft contact lenses are more comfortable than hard contact lenses because they hold more water and they do not sit directly on the cornea.
Contact lenses are often given a slight color to make them easier to handle.
HISTORY OF CONTACT LENS
The history of contact lens dates back more than 500 years
1508 Leonardo da Vinci illustrates the concept of contact lenses
1823 British astronomer Sir John Herschel conceptualizes practical lens design
1887 First contact lens manufactured from glass, and fitted to cover the entire eye
1939 Contact lenses first made from plastic
1948 Plastic contact lenses designed to cover only the eye's cornea
1971 Introduction of soft contact lenses
1978 Introduction of GP contact lenses
1981 FDA approval of new soft contact lenses for extended (overnight) wear
1986 Overnight wear of GP contact lenses becomes available
1987 Introduction of disposable soft contact lenses
1987 GP contacts available in next-generation fluorosilicone acrylate materials
1996 Introduction of one-day disposable soft lenses
2002 Silicone-hydrogel contact lenses first marketed
2002 Overnight orthokeratology approved by FDA
2010 Custom-manufactured silicone-hydrogel lenses become available.
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