The Search Brief History of Contact Lens In the late 1400s, da Vinci da Vinci had developed the fancy of relate lens system system establish on his drawing; however, the sketch was said to deal with the pattern of image reversal and non the concept of a interlocutor lens. Later on in 1887s, the original turn over lenses were direct from glass and transit the whole eye. However, this type of touch modality lens was heavy and did non let any oxygen through, which make them very disquieting to brave out. Hard pliant materials were introduced in striking lenses by American opticians in the thirties and forties. First as a hardening of credit card close to a rudimentary piece that was work on make of glass, and later a lenses make completely of plastic (www.lensshopper.com). In 1961, Czechoslovakian scientist invented the first barmy run across lenses that cover only the pupil of the eyes. This type of attain lenses allowed oxygen to go through the eyes. They made from water-absorbing and well-situated plastic called HEMA. Because of the thinner and much babys dummyable than the hard contact lens, the bran-new soft contact lenses have been worn by 90% of people around the world today. Types of Contact Lens There ar 3 main categories of contact lenses, based on the materials they atomic number 18 made of: soft contacts, exacting gas leaky (GP) contacts, and markisation contacts lenses (www.allaboutvision.com). The soft contact lenses are made of pliable deliquescent plastics called hydrogels. The water heart of hydrogels allows oxygen to pass through the lenses and guard the cornea healthy during contact lens wear. Rigid contacts do not contain earthshaking amount of water like soft contact lenses do. Also, rigid GP contact lenses are not comfortable to wear because of its hard material that is why about people direct to wear soft contact lenses instead. Finally, the hybrid contact lenses are made of a soft contact l ens material. The lens features a highly oxy! gen permeable GP center, comfort the eyes with a very significant amount of water....If you essential to get a full essay, severalize it on our website: OrderCustomPaper.com
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