A trio of South Korean designers, Ji-youn Kim, Soon-young Yang, and Hwan-ju Jeon, have come up with a clever concept called the Uni-Signal, a traffic light which combines color and positioning with shapes to indicate when it's appropriate to stop and go.
The light aims to avoid the dangers caused by colorblind drivers or foreigners who don't know the local ways of the road. It does this by changing the shapes of the colored lights. Instead of using three circles, the red light is now a triangle and the green light is a square. The amber lamp remains round and central, just as it always was.