The retina is a small, thin tissue lining the back of the eye. Within the center of the retina is the macula containing a large concentration of light receptor cells called cones. Cones are necessary for sharpness of vision, allowing us to see fine details of objects, as well as color vision. The peripheral area of the retina contains fewer cones and a larger concentration of another type of light receptor cells called rods. Rods make it possible to see in dimly lit conditions. Allowing us to see objects to the right and to the left, the peripheral retina enables us to walk, function and move about safely.
The cornea and the lens focus light images from objects in our field of vision onto the retina, stimulating an electrical response in the retina. As a result, the optic nerve carries electrical signals from the retina to the brain where the signals are processed; allowing us to see and understand what it is we are seeing.