Garrett Augustus Morgan, Sr. (March 4, 1877 – July 27, 1963)

Morgan had witnessed a serious accident at an intersection, and he filed a patent for traffic control device in 1922.

In 1923, the U.S. Patent Office granted Patent No. 1,475,024 to Garrett Morgan for his three-position traffic signal. Though Morgan's was not the first traffic signal (that one had been installed in London in 1868), it was an important innovation nonetheless. By having a third position besides just "Stop" and "Go," it regulated crossing vehicles more safely than earlier signals had.