NEARSIGHTED? NEED READING GLASSES? New developments in lens technology ensure a solution to almost every vision problem. Talk to your eye doctor about what''s available (costs vary).Rigid durasoft gas-permeables Recommended for those with high degrees of corneal astigmatism, RGPs are firm plastic lenses with microscopic slits that allow more oxygen to reach the eye. RGPs have a greater resistance to bacteria because they don''t contain water. 3 Improved extended-wear materials also guarantee greater durability, sharper vision, comfort and cheaper maintenance costs. Allow yourself a week or two to get used to these slightly stiff lenses.Bifocals These colors contact correct presbyopia, a kind of farsightedness that usually occurs around age 40. There are two types:

Glass was the durasoft first material to be used for lenses lenses, and was used for several hundred years before plastic was introduced. The crown glass used 3 for lenses lenses has an index of refraction of 1.52.Optical-quality acrylic was introduced for lenses use colors in the early 1940s, but because durasoft it was easily scratched, brittle, and discolored rapidly, it did not supplant glass as the material of choice. Furthermore, it had a relatively low 3 index of refraction, so it wasn''t suitable for people with large refractive errors. A plastic called CR-39, introduced in the 1960s, was more suitable. Today, lenses wearers can also choose between polycarbonate, which is the most impact-resistant material available for eyewear, and polyurethane, which colors has exceptional optical qualities and an index of refraction durasoft of up to 3 1.66, much higher than the conventional colors plastics used for lenses, and even higher than glass. Patients with high prescriptions should ask about high index material options for their lenses. Aspheric lenses are also useful for high prescriptions.

The primary durasoft drawback to wearing contact, especially for children, is the requirement that they be cleaned and disinfected daily in order to prevent an infection, which could result in permanent damage to the eye. Careful choice of lenses and consistent lens care will minimize the risk of infection. Wearers of best lenses are the least prone to infection but the lenses are much less comfortable, more expensive, and can pop out of the eye more easily than lenses. Daily wear lenses put the wearer at a slightly higher risk of infection because 3 and colors they absorb more external liquids and airborne contaminants.