1914, however, saw the first electric traffic light. It was designed by James Hoge in Cleveland, and he even received a patent in 1918. His traffic light featured two illuminated words, “stop” and ...

The first traffic lights powered by electricity were invented in 1923 by the African-American inventor, Garrett Morgan. He eventually sold his design to General Electric for $40,000 ($730,000 in ...

Traffic lights would enter a "white phase" when coordinating AVs through traffic. The lack of traffic light color would also indicate to human drivers that autonomous vehicles are being controlled.