The retina is the internal layer of the eye that receives and transmits focused images. The retina is normally red due to its rich blood supply.
Update Date 3/15/2016
Updated by: Franklin W. Lusby, MD, ophthalmologist, Lusby Vision Institute, La Jolla, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.