Your eyes are amazing machines, but it takes only one small imperfection in the shape of your cornea or the lens of cause fuzzy focusing. Doctors call these imperfections astigmatisms, and they’re often inherited from parents. Glasses and contact lenses (or corrective surgery) can fix the problem.
Glasses or contact lenses correct vision because they allow the eye to focus light in the right spot on the retina — the spot that produces the clearest image. Because everyone’s eyes are different, a pair of glasses that makes one person see wonderfully may look terribly blurry to someone else. You know this if you’ve ever tried on somebody else’s glasses!
If you need glasses or contact lenses, your doctor will write you a prescription. In this case, a prescription doesn’t mean medicine you’ll pick up at the drugstore. A vision prescription is a piece of paper with numbers on it. The people who will make your glasses for you need these numbers to create lenses that will correct the way your eye bends light. Remember, the target is right in the center of the retina.
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