Definition of the Traffic Light: The Traffic Light is defined as a road signal, also known as a stop light, for directing and controlling the flow of motor vehicles at intersections, crossroads, junctions, etc in towns and cities by means of colored lights, typically red for stop, green for go, and yellow for proceed with caution. Traffic lights are complimented by Pedestrian lights that indicate when it is safe to walk across the road allowing both cars and people to take their turn in an orderly fashion.
What's the difference between a Traffic Light and a Stop Light? The terms Traffic Light and Stop Light both mean a traffic control signal. The American term 'Stop Light' is not used by the British, in the UK this would be understood to mean specifically a 'red traffic light', whereas the term Traffic Light encompasses the three red, orange and green lights.
Fact 1: Who invented the Traffic Light? The Traffic Light was invented by Garrett Morgan in 1923 during the Interwar Era of inventions (1918 - 1939) which was a leading advancement in the area of safety and transportation.
Fact 2: Who invented the Traffic Light? Prior to the invention of the Traffic Light in 1923, there was a boom in the sale of Cars in America. Car travel increased massively but there were no controls in place to regulate the flow of traffic which led to numerous accidents and safety issues.
Fact 3: Who invented the Traffic Light? The history of the Traffic Light began long before the invention of the automobile. Horse drawn carriages and darting people crowded the roads of major cities, causing accidents and general chaos.
Fact 4: Who invented the Traffic Light? John Peake Knight (1868): The problem of traffic and crowd control was first addressed in London by an English railway engineer and inventor called John Peake Knight (1828 - 1886). John Peake Knight invented the first, non-electric, gas-lit traffic lights in 1868. J.P. Knight adapted railway signalling systems to address the problem of traffic control in London.
Fact 5: Who invented the Traffic Light? The Gas-lit Traffic Light (1868): The gas-lit Traffic Light system invented by John Peake Knight used a sytem of semaphores that would signal "stop" and "go" during the day. At night Gas lamps were used to illuminate the signs at night. This was a totally manual system requiring a police officer to be stationed next to the Traffic Light signals to operate them. The gas-lit system was introduced in London on December 9, 1868 and operated on Bridge Street and Great George Street near the Houses of Parliament and Westminster Bridge.
Fact 6: Who invented the Traffic Light? The Gas-lit Traffic Light (1868): The gas-lit light system was doomed to failure due to the use of gas. Just one month after the gas-lit Traffic Light system was installed a policeman controlling the signal system was seriously injured when a leak in a gas main caused one of the lights to explode in his face. The world's first traffic signal was declared a public health hazard and immediately abandoned. It would be another 40 years, and the advent of electricity, before the history of the Traffic Light would continue.
Fact 7: Who invented the Traffic Light? The Age of Automobile: The invention of the automobile and the introduction of the low priced Ford Model T car in 1908 resulted in a boom in the American automobile industry. The assembly line process enabled Ford to produce massive numbers of Model T automobiles. Between 1908 and 1927 15,007,034 Model T vehicles were sold.
Fact 8: Who invented the Traffic Light? Earnest Sirrine (1910): The history of the Traffic Light picked up again in 1910 when an American inventor called Earnest Sirrine patented an automatically controlled traffic signal using two, turning, non-illuminated, words Stop" and "Proceed". The Earnest Sirrine traffic signal was patented on April 28, 1910 and operated in Chicago. It used two, turning non-illuminated display arms arranged as a cross that rotated on an axis.
Fact 9: Who invented the Traffic Light? Lester Farnsworth Wire (1912): In 1912 the American Inventor, Lester Wire, invented the first electric traffic light using red and green lights. This traffic light was powered from overhead trolley wires. It was a basic system requiring a police officer to manually switch the direction of the lights. The color red was chosen as it indicates danger. The color green was chosen as it is closely associated with safety and is the polar opposite of red.
Fact 10: Who invented the Traffic Light? James Hoge (1913): In 1913 the American inventor James Hoge patented a manually controlled traffic light that used electric-powered lights to display the illuminated words "Stop" and "Move". The major advantage of the James Hoge traffic light system was that it was wired so that in emergencies police and fire departments could adjust the rhythm of the lights.
Fact 11: Who invented the Traffic Light? William Ghiglieri (1917): In 1917 the American William Ghiglieri patented the first automatic traffic signal on May 1, 1917 using red and green colored lights. The major advantage of the Ghiglieri traffic light system could be used either automatically or manually.
Fact 12: Who invented the Traffic Light? William Potts (1920): In 1920, William Potts, a Detroit police officer, invented the three-lens traffic light. It was the first automatic electric system to use an orange light. The color orange, or amber, has very high visibility, so it was chosen to catch the attention of the car driver.
Fact 13: Who invented the Traffic Light? Garrett Morgan (1923): The black American inventor of the electric automatic Traffic Light, Garrett Morgan was a prolific inventor who also famous for the invention of the Gas Mask. Garrett Augustus Morgan was born on March 4, 1877 in Claysville, Kentucky and died on July 27, 1963. In 1923 Garrett Morgan invented an inexpensive version of the electric automatic Traffic Light, increasing the number of Traffic Lights that could be installed.
Fact 14: Who invented the Traffic Light? Electric automatic Traffic Light (1923): The Garrett Morgan traffic light used a T-shaped pole with three positions. A major advantage of his system was that it was cheap to produce and also the first traffic light to stop cars in all directions to give the drivers time to stop or get through the intersection.
Fact 15 - Impact: How did the Traffic Light impact the world? The impact of the invention of the Traffic Light was a paramount step to improving the field of Transportation.
More Interesting Facts: Pedestrian signals began to be included in the 1930s and the "Walk / Don't Walk" signal was first tested in New York City on February 5, 1952. The first parking meter was invented by Carlton Cole Magee in 1932 as a solution to the growing problem of parking congestion.
Traffic Light Colors? The red, green and orange colors of the Traffic Light were chosen for specific reasons. The color red has always been associated with danger. Green is the polar opposite of red and closely associated with safety (think of advertising medical products). Orange or amber has very high visibility, so it is used to catch attention.
The Inventors Now you know that John Peake Knight, Earnest Sirrine, Lester Wire, James Hoge, William Ghiglieri, William Potts and Garrett Morgan were involved with the invention of the Traffic Light! We hope that the facts in this article have provided the answers to all of your questions about the invention and its famous inventors.