According to ancient beliefs our eyes emitted beams of light that allowed us to see whatever we looked at. Today, we know the physics of seeing is exactly the opposite.
Light waves enter our eyes through the cornea, then pass through a lens, which focuses the light on the rear of the eyeball. There, the light excites special nerve endings, called rods and cones, which carry a signal to the brain.
Depending on the shape of the eyeball, the cornea, lens, and retina may not work perfectly together, causing fuzzy vision. Thats why many people wear eyeglasses or contact lenses. They help the light focus images correctly on the retina and allow people to see clearly.
Almost everyone will experience some eye trouble at one time or another. For example, your eyes might feel strained, dry, bloodshot, or itchy. Make sure to see your eye care professional for any problems that last more than a day or two.
There are several things you can do each day to maintain eye health and avoid problems. Drink eight to ten glasses of water to keep your body and eyes hydrated. Make a conscious effort to stop periodically to rest and blink frequently especially when reading, working on a computer, or watching television. Avoid rubbing your eyes. And remember to always protect your eyes from the sun`s harmful UV light and glare with protective lenses.