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Vision


Eyeglasses
Vision Problems
Contact Lenses
Fitting Contact Lenses
Contact Lens Prescription
Contact Lens Complications
Caring for Contact Lenses
Sunglasses



Eyeglasses

      Eyeglasses have come a long way since the first appearance of a magnifying glass around 1000 BCE. Today, eyeglasses have moved from the realm of vision to the world of style and fashion. This is good news for those with vision problems, as they now have great choice when selecting the eyeglasses that are right for them.
      Eyeglasses are the number one vision accessory in use today. Having said that, with contacts becoming increasingly more comfortable to wear and the replacement cost of contacts and other online stores going down, contact lenses are becoming increasingly popular.
      Some people experience complications with eyeglasses. The usual culprit is a reaction to the frames being worn that often come with discount eyeglasses. This is most often the result of a reaction to the nickel alloy used in making the frames. There are now several alternate options available, including frames made from titanium, gold, silver or stainless steel. As well, plastics such as polyamide, nylon and polycarbonate are usually hypoallergenic. A less frequent problem experienced by those wearing eyeglasses is an allergy to the nose pads on metal frames. In these cases, PVC or titanium can be used to manufacture the nose pads. These products are usually hypoallergenic.



Types of Lenses

High Index Lenses

High Index lenses are ideal for those who have strong prescriptions, but do not want to wear the "coke bottle" glasses of the past. These lenses are made with materials that are lighter in weight and thinner than their regular glass or plastic counterparts. The term high index is used because the materials used in making these lenses have a higher index of refraction. The index of refraction is the speed that light travels as it passes through the lens material.

Bifocals/Multifocals

Bifocals or multifocals no longer need to have a line through the middle of the lens. These glasses have come a long way and special glasses are now available for computer users and for other unique work situations. These eyeglasses enable the wearer to see or focus at various distances through the same lens. There are a variety of reasons why people need to focus differently at different distances, but bifocals or multifocals offer an effective solution.

Near vision correction

works by having a small portion of the lens used specifically for this purpose. This portion of the lens can be many shapes, including round, rectangular or half moon. The remaining part of the lens usually provides vision correction for distance, but can also provide no correction at all.

Trifocals

These lenses provide three different points of focus, most often for near, intermediate and far distances.

Progressive lenses

These lenses are often called no-line bifocals. They enable vision correction at distances that most bifocals do not, at the same time as providing near vision correction. They are a near and distance correction lens in one and provide a smooth transition from seeing at far distances, to intermediate distances, to close up - and everything in between.




The National Eye Institute (A Division of the National Institutes of Health) offers excellent resources about vision, eye care and contact lenses. This site is available in both English and Spanish. The Optometrists Network provides detailed information for parents about children and vision care.




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