This Ad's Amazing Optical Illusion Reveals the Hazards Of Driving

Audi's luxury vehicles include a neat night-vision system that will automatically warn drivers about hazards on the road. And to drive home just how life-saving it can be, the company's ad agency created a brilliant billboard in an airport with a secret hazard that was only revealed to passengers when they got closer and closer.

Using a physical phenomenon called accommodation, the ad cleverly manipulated how the human eye focuses so that the slightly blurred text revealed an additional message—created using just outlines—as the viewer got closer to it. In this case it was placed in a spot where airport passengers on a moving sidewalk saw it guaranteeing the neat effect would be noticed. Remember, it's all fun and games unt—A DEER! [Vimeo via Taxi]