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the miracle of lasik operation at EyeSTAR in Istanbul, Turkey
HOW DO WE SEE?

how the eye functionsThe eye functions like a camera or more like a video camera. Light rays coming from the objects arrive on the cornea first. The cornea provides 70% of the refractive power of the eye. After refracting the light rays, it directs them to the lens through an aperture called the pupil. The lens bends, in turn, refracts the rays again. It makes a fine adjustment to focus the light rays on the retina. This adjustment is similar to the auto-focus function of cameras. This superb, silent and continuous auto-focus function is due to the lens' ability to change its refractive power by altering its form and thickness. This function is called accommodation. In a non-accommodating young eye the refractive power of the lens is below 20 diopters but with maximum accommodation it increases to more than 30 diopters, which is nearly equal to an 8.5 diopters increase in the eye's total refractive power. Because of this ability the young eye can see both near and far objects well.
After the light rays are bent at the lens, they pass through the vitreous, the jelly-like substance filling the back part of the eyeball, and reach the retina. The retina, which makes up the inner lining of the eyeball functions like a camera film, or a CCD of a digital video camera. Then light rays are converted into electrical impulses by the retina and carried to the brain by the optic nerve. These impulses are processed and perceived as images by the brain.
 
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