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 gas-permeables Recommended for those with high degrees contactsdiscount 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. 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 contactsdiscount slightly stiff lenses.Bifocals These contact correct presbyopia, a kind of farsightedness that usually occurs around age 40. There are two types: Rimless frames are the least noticeable type, and they are lightweight because the nosepiece and temples are attached directly contactsdiscount to the lenses, eliminating the weight of the rims. They tend to not be as sturdy as frames with rims, so they are not a good choice for people who frequently remove their glasses and put them on again. They are also not very suitable for lenses that correct a high degree of farsightedness, because such lenses are thin at the edges.Metal frames are less noticeable than plastic, and they are lightweight. They are available in solid gold, gold-filled, anodized aluminum, nickel, silver, stainless steel, and now titanium and titanium alloy. Until the late 1980s, when titanium-nickel alloy and titanium frames were introduced, metal frames were, in general, more fragile than plastic frames. The titanium frames, however, are very strong and lightweight. An alloy of titanium and nickel, called Flexon, is not only strong and lightweight, but returns to its original shape after being twisted or dented. It is not perfect for everyone, though, because some people are sensitive to its nickel. Flexon frames are also relatively expensive. (Lenses made from polycarbonate, the same type of plastic used for the space shuttle windshield, are contactsdiscount about 50 times stronger than other lens materials.) Also, people at risk of receiving electric shock should avoid metal frames.People employed in certain occupations may be prohibited from wearing contact, or contactsdiscount may be required to wear safety eyewear over the contact. Some occupations, such as construction or auto repair, may require safety lenses and safety frames. Physicians and employers should be consulted for recommendations. Description Eyes are examined by optometrists (O.D.) or by ophthalmologists (M.D. or D.O.--doctor of osteopathy). Prescriptions, if necessary, are then given to patients contactsdiscount for glasses. The glasses are generally made by an optician. A separate lenses-fitting exam is necessary if the patient wants contact, because an lenses prescription is contactsdiscount not the same as a lenses prescription.
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