Sight is an amazing process made possible by many parts of the eye working together. Light enters the eye and is bent or refracted by the cornea (the window of the eye) through the pupil (the opening in the iris). This light passes through the lens (located behind the pupil). This completes refraction by fine tuning the focused light onto the retina. The retina changes the light (energy) into electric impulses that are carried through the optic nerve to the vision center (occipital cortex) of the brain where the image is interpreted.