The intricate process of vision, which has so many complex parts and interactions, can sometimes go wrong. The four most common vision problems - nearsightedness, farsightedness, astigmatism and presbyopia - are usually caused by focusing problems of the cornea or the lens or by an abnormal shape of the eye. Most problems with focusing can be corrected with eyeglasses, contact lenses or surgery that adjusts the curvature of your cornea.
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| Nearsighted Vision Correction |
You see an object clearly when it is properly focused. That means your cornea and lens have adjusted the point of focus so that an image falls sharply defined onto your retina. If the focusing powers of your cornea and lens aren't coordinated with the length or the shape of your eye, however, the image you see is blurred.