The healthy eye works very much like a camera. Light passes through a series of lenses in the front of the camera, and is focused upon the film in the back of the camera. In the eye, the light passes through the cornea, lens, and vitreous gel, and is then focused on the retina. The retina works like the film in the camera. The information gathered by the retina is then sent to the brain via the optic nerve.
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