A brief history of traffic signals
The first traffic light was installed at the intersection of George and Bridge Street near the Houses of Parliament in London on the 10th of December 1868. It was invented by J. P. Knight with railway signal semaphore arms and was operated by a traffic policeman. A gas lantern at the traffic light’s tip showed a red or green light at night, depending on the position of the semaphore arms. It has been in use for four years.
The first electric traffic signal using red and green lights was installed in Salt Lake City, USA in 1912. The traffic lights installed in Cleveland, USa on the 5th of August 1914 is said to be the world’s first regular traffic light. In 1917 the first automatic traffic signal was patented in the USA. The first tower for traffic regulation to manage the high traffic volume was installed at an intersection in Detroit, USA in the same year.
In 1920 the first three-coloured traffic lights with red, yellow and green lights were put to service in New York and Detroit, USA. The first traffic lights in Europe were installed in Paris (Rue de Rivoli, Boulevard de Sebastopol) and Hamburg (Stephan Square) in 1922. The traffic light, which was installed on the 21st of October 1924 at Potsdam Square in Berlin, earned some fame. This traffic light was a square tower with 3 metres height. A clock was placed at the top of the tower. There was a cabin for the policeman and the traffic lights in colours red, green and blue (instead of yellow) as well as white. This tower regulated the whole traffic, including pedestrians. They were allowed to cross the street when the white light was showing.
Ulrich Giersch said something like “Universal time, signal clocking and supervision were melded in this tower on a central spot”.
The first pedestrian light in Europe was installed in Copenhagen, Denmark in 1933, and Germany’s first in Berlin in 1937. On February 5th in 1952 the first automatic pedestrian light showing the well-known “walk” and “don’t walk” signals was installed in New York.
The 13th of October 1961 is said to be the birthday of modern pedestrian lights with pictograms. On that day, Karl Peglau, Executive Traffic Psychologist in Eastern Berlin, published his new idea of regulating the pedestrian lights with man-schemed signals. There had to be some new concept development for pedestrian lights, because of increasing traffic volume and high numbers of accidents. Until then they had been small-sized traffic lights. Peglau’s formal principles were concreteness, archetypal behaviour symbols, distinctive feature and emotional responsiveness.
In the mid-sixties the first pedestrian lights displaying “Ampelmännchen” were seen in Eastern Berlin’s streets. In 1970 they were approved of by GDR Traffic Authorities and hereafter installed all over the GDR. From 1982 onwards the “Ampelmännchen” was used in GDR TV for educational purposes concerning traffic. Even though the little traffic man was the best developed shape, regarding perceptual psychology, it did not spread worldwide. The less demanding designs prevailed.
A significant innovation was created in Taiwan in 1999. The upper part of the pedestrian light shows a countdown whereas the lower part shows a manikin. This manikin starts walking, coloured in green and then moves faster and faster in the last ten seconds until it stops at zero and becomes a standing red manikin. This animation was designed by Lin Li-Yu, Deputy Director of Taipei City Department of Transportation, and consists of a sequence of seven stick figures with an increasing display speed.
