Biography:George Wald was awarded the Nobel prize for Physiology or Medicine in 1967 along with Ragnar Granit and Haldan Keffer Hartline "for their discoveries concerning the primary physiological and chemical visual processes in the eye".
In particular Wald was responsible for identifying retina A as essential to the function of the eye.
1967-12-10 Nobel Prize in Physiology or Medicine awarded to Ragnar Granit, Haldan Keffer Hartline and George Wald "for discoveries about the make-up of the eye