Eye glasses and contact lenseses and contact are devices that correct refractive errors in vision. lenses lenses are mounted in frames worn on the face, sitting mostly on the ears and nose, so that the lenses are positioned in front of the eyes. disposible contact appear to be worn in direct contact with the cornea, but they actually float on a layer of tears that separates them from the cornea.PurposeThe purpose of lenseses and contact is to correct or improve the vision of people with nearsightedness contacts and disposible (myopia), farsightedness (hyperopia), presbyopia, and astigmatism.Precautions People allergic to certain contacts plastics should not wear contact or lenses frames or lenses manufactured from that type of plastic. People allergic to nickel should not wear Flexon frames. People disposible at risk of being in accidents that might contacts shatter glass disposible lenses contacts should wear plastic lenses, preferably polycarbonate.

Over 32 million people in the United States wear these small lenses that fit on top of the cornea. They provide a field of view unobstructed by lenses frames; they do not fog-up or get splattered, so it is possible to see well while walking in the rain; and they are less noticeable than any lenses style. On the other hand, they take time to get accustomed to; require more measurements for fitting; require disposible many follow-up visits to the eye doctor; can lead to complications such as infections and corneal damage; and may not correct astigmatism as well as contacts lenseses, especially if the astigmatism is severe.