The AR coating is layers of this film on the two sides of the lens.
Layers made of oxides(7 + 7) resulting in a destructive system which reduce the reflactions across the spectrum of visible light. visible sectrum is range of light which our eye can detect in the universe.
As it is broad band A/R coating it nullufy ghost images and produce sharp and crisp clear images. gives the feel as if there is no lens in the frame.