Correcting the Vision
Vision is extremely important for every single action weperform daily. When there is some problem with the vision, many people will instantlygo to their doctor for the eye check up. Both spectacles and contact lenses maysignificantly improve the vision, but what suits who is not easy to answer. Thesedays, there is an increasing number of people moving from eyeglasses tocontacts.
Wearer of contact lenses are mainly people at their 40s (40to 45 years of age). Children who have troubles with their vision may also usecontact lenses. However, most of the kids outgrow their problem and don’t haveto wear the contacts after some time. Presbyopia is medical term used to describe inability toclearly see things located close to the person. For these patients, contactlenses can improve vision of both near and far objects and this is the reasonmany of them throw away the glasses and start using contact lenses instead.
Types of Bifocal Contact Lenses
Bifocal contact lenses, as their name suggests, have twofunctions. Upper half of the lenses is designed to help people to see someobjects located far away. On the other hand, people can see something very nearsimply by using the lower part of these bifocal contact lenses. Because of thisit is said that bifocal lenses have two types of power.
Bifocal or multifocal lenses, as they are sometimes alsoknown, can be soft or rigid. According to the design of the lenses, there are two distinctivetypes of bifocal contacts: alternating vision lenses and simultaneous visionlenses.
Alternating vision lenses can adjust the power between thepupils of the eyes as they move. However the pupils move, in whateverdirection, up or down, the lenses simply adjust. These lenses work in the samemanner as bifocal glasses. Looking straight ahead through the lenses, theperson is able to see something very far. To see something close to them, thesepatients will have to look downward through the contacts. Alternating bifocalcontacts are smaller than other contact lenses and they are usually rigid and gas-permeable.
Simultaneous vision lenses help the person wearing them to seeall objects at the same time, no matter how far or close they are. Simultaneouscontacts may be concentrated rings or of aspheric design. In concentratedrings, there is one prescription in the center of the lens and one or two morearound the center. Aspheric bifocal lenses have multiple prescriptions blendedinto the lens.