The retina is a light-sensitive layer at the back of the eye which contains the receptors for vision. The center of the retina is called the fovea and has mostly cones.
The fovea is a small dimple located in the middle of the retina and it is a location of most color perception.Cones are the photosensitive cells. They convert incident light energy into signals that are carried to the brain by the optic nerve.