Last modified on July 13, 2016, at 18:26


The retina occupies the back of the eye and contains the photoreceptors that capture light rays and convert them into electrical impulses that are turned into images by the brain.

Photoreceptors come in two forms, rods and cones. The rods are for black and white vision and are the most plentiful, each eye having about 125 million rods. They work best at night. Cones gives us color vision and work best in the daytime. Each each has about 6 million cones.