Eye structures and vision

In a normal eye, light passes through the pupil and is focused by the lens onto the retina at the back of the eye. The retina converts light into electrical impulses that are carried to the brain. The brain interprets the impulses as visual images.

One part of the retina—the macula—provides sharp, clear central vision that allows a person to see form, color, and detail that is directly in the line of sight.