A contact lens is a lens that is placed onto the cornea of the eye. The lens is usually used to adjust eyesight, often used as an alternative to eyeglasses. People choose to wear contacts for a variety of reasons, but they are usually worn for sports, weather, and to change physical appearance. In 2004, it was estimated that roughly 125 million people wear contact lens.
Contact lenses come in a variety of forms. They are soft contact lenses, rigid gas permeable contact lenses, extended wear contact lenses, disposable contact lenses, orthokeratology contact lenses, and decorative (piano) contact lenses. The differences between the lenses are the amount of time users are expected to wear them, the material they are made out of, durability, and whether they correct vision or not. The most popular contact lens brands are created by CIBA Vision, CooperVision, Johnson & Johnson, and Bausch and Lomb.
The history of contacts, on the other hand, is surprising longer than most people think.
In 1508, Leonardo da Vinci introduced the concept of contact lenses to the world. He created the “Codex of the eye, Manual D”. In this manual he discusses changing the corneal abilities by putting people’s eyes into a bowl of water.
In 1801, Thomas Young developed contact lenses that did not correct refraction errors. His contact lenses involved water-filled gel and were highly unrealistic. In 1823, Sir John Herschel was one of the first to actually create plans to create practical contact lens designs.
In 1887, F.E. Muller created the first contact lenses that were actually bearable to the human eye. Adolf Gaston Eugen Fick was the first ophtalmologist to fit a pair of contact lenses on to living creatures. He originally tried them on rabbits, eventually put them on himself, and finally had a group of volunteers test them. Although the lens was tolerable, it couldn’t be worn for long periods of time.
In 1948, plastic contact lenses were created, and these only covered the eye’s cornea. They could be worn for at most 16 hours. The best transformation in the contact lens world occurred in 1960 when two Czech chemists Otto Wichterle and Drahoslav Lim created soft lenses. Once soft contact lenses were brought into the world, the contact lens industry took off. Since then, other contact lenses have been developed. There are now contact lenses made out of several different materials and lengths of durability.