Comments from the man who built the first LED traffic lights (2024)

FAQs

What was the purpose of the first traffic light? ›

Traffic lights were first introduced in December 1868 on Parliament Square in London to reduce the need for police officers to control traffic. Since then, electricity and computerised control has advanced traffic light technology and increased intersection capacity.

Potts became the 'superintendent, signal person police' for the city of Detroit. The old system of police directing traffic had become increasing outmoded; two-color signals, with green and red lights, already existed, but they did not leave drivers sufficient time to stop at high speeds.

Morgan's experiences driving through the streets of Cleveland are what led him to invent the nation's first patented three-position traffic signal. Garrett A. Morgan's illustration for his T-shaped traffic signal patent in 1923.

Red light on: This tells drivers to stop. Green light on: This means the driver can start driving or keep driving. Yellow light on: This tells drivers to stop when it is safe to, because the light is about to turn red.

Gas was fed into the mechanism from a pipe in the ground to power the lights. Unfortunately, the first design of the traffic light had a rough start. A gas leak from the supply pipe beneath it triggered an explosion in the traffic light mechanism, injuring the policeman operating it.

As cars became more ubiquitous, however, so did injuries and deaths from car accidents. One of the biggest issues was intersections, where cars, horses, and pedestrians tried to move through simultaneously. The solution was something that we're all used to seeing today – the traffic light.

Many of the world's most famous inventors only produced one major invention that garnered recognition and cemented their prominent status. But Garret Augustus Morgan, one of the country's most successful African-American inventors, created two – the gas mask and the traffic signal.

The simple device tamed the streets; motor vehicle fatality rates in the United States fell by more than 50 percent between 1914 and 1930. And the technology became a symbol of progress.

John Peake Knight is credited with the invention of traffic lights, and his story is interesting. He was born in 1847 and worked as a railway signal engineer. In 1868, he filed a patent for a traffic signal that would allow trains to pass safely.

How many lives did Garrett Morgan save? ›

Morgan said in his diary, "I had but a little schooling, but I am a graduate from the school of hard knocks and cruel treatment. I have personally saved nine lives." He was also given a medal from the International Association of Fire Engineers, which made him an honorary member.

A three-way signal refers to an intersection at which opposing directions do not have concurrent greens. ( Staff archives)

Respect the traffic light. Stop if the light is amber and it is about to change to red rather than making a desperate dash to get to the other side.

Traffic light meaning is fairly consistent across the board and various deviations. Green means it's safe to proceed (though you should still exercise caution). Yellow means caution and yield. Red means danger and stop.

Traffic signals are designed to ensure an orderly flow of traffic, provide an opportunity for pedestrians or vehicles to cross an intersection and help to reduce the number of conflicts between vehicles entering intersections from different directions.

Signals offer maximum control at intersections. They relay messages of both what to do and what not to do. The primary function of any traffic signal is to assign right-of-way to conflicting movements of traffic at an intersection.

Morgan invented what has come to be known as “the yellow light.” And, in his Nov. 20, 1923, patent granted by the U.S. Patent and Trademark Office, Morgan cited one reason for the invention was to alleviate a driver behavior that's still prevalent in 2023 — drivers honking when a light turns green.

By 1930, all major American cities and many small towns had at least one electric traffic signal, and the innovation was spreading around the world. The simple device tamed the streets; motor vehicle fatality rates in the United States fell by more than 50 percent between 1914 and 1930.

Croton-on-Hudson, New York and Beacon, New York can both lay claim to having the oldest traffic light in America. Both traffic lights, installed in 1926, are still in use today and are known as a dummy light. Both lights are non-approved devices by current DOT standards.