A traffic light was invented by a textile worker in 1859 and was first used in the United Kingdom. Later, it was banned due to accidents. It was not until 1914 that the city of Cleveland in the United States took the lead in restoring traffic lights.
With the advent of the industrial age, especially the emergence of high-speed carriages and cars, conventional traffic habits alone can no longer guarantee smooth traffic, nor can it protect the safety of pedestrians and vehicles. So in 1868, the world's first traffic light with the function of directing traffic appeared in the United Kingdom. It is said that the reason why the red light is prohibited and the green light is passed is based on the dressing style of women in Yorkshire, England at that time: wearing a red skirt means married, and a green skirt means unmarried. In fact, this was not the case. At that time, people had already studied spectral physics. Red has the strongest penetrating power, so as a no-travel sign, the opposite color corresponding to it is green, so it was chosen to indicate passage.
Interestingly, the person who first invented the traffic light was actually a textile worker. He came up with a way to control traffic with light colors, and in 1859 he brought an oil lamp with a movable canopy device. Arriving in London, however, the invention was ridiculed. It was not until a few years later that high-speed carriages frequently caused accidents on British streets that the government remembered this invention.
On December 10, 1868, the first member of the signal light family was born in the square of the Houses of Parliament in London. The 7-meter-high lamp post was designed and manufactured by De Hart, a British railway signal engineer at the time. , hanging on his body was a red and green lantern - a gas traffic light, which was the first signal light. At the foot of the lamp, a policeman holding a long pole changed the color of the lantern by pulling the belt. Unfortunately, a gas lamp suddenly exploded 23 days after its release, killing a policeman on duty. Since then, traffic lights in the city have been banned. It was not until 1914 that the city of Cleveland in the United States took the lead in restoring traffic lights.
The advent of yellow lights was due to the increase in vehicle speed
During World War I, traffic lights in the modern sense began to appear on American streets. The reason why modern traffic lights first appeared in the United States is because Europe was ravaged by war at the time, and the United States took advantage of the situation to rise. The number of motor vehicles increased sharply, and the intersections with cars became more and more dangerous. Therefore, electric traffic lights and linkage traffic lights successively Comes out in the United States.
With the "silent command" of traffic lights in the United States, road traffic has become more orderly and safer, which has promoted the United States to become the first "country on wheels" in the world. Stimulated by the country's patent applications and economic development, dozens of technologies related to traffic light rules were promoted. Flow control lights and computer-controlled traffic lights appeared successively, becoming the "originator" of modern traffic light rules.
The popularity of yellow lights came a little later. One of the main reasons for the appearance of yellow lights is that vehicles are traveling faster and faster. If a vehicle with a speed of 20 kilometers per hour can stop in time when the green light changes to a red light, then it becomes more difficult for a vehicle with a speed of 40 kilometers per hour to stop in time: first, because sudden braking may cause a rear-end collision; Cause additional damage; secondly, according to the theory of physical inertia, a sudden stop is also very difficult to achieve.
Many Chinese materials suggest that the inventor of the yellow signal light was the Chinese Hu Ruding. The time was 1927. Hu Ruding, who was studying in the United States at that time, thought that adding a yellow signal light between red and green lights would be safer. However, it is recorded that the world's first red, yellow and green, four-way traffic light was put into use in October 1920. This signal light invented by policeman William Potts was installed at Woodward in Detroit. Intersection of Main Street and Ford Street. The use of yellow represents "proceed with caution", and the railway system has also been used for a long time. In 1899, the railway systems of New York, New Haven and Hadford used three-color lights, red means "stop" and green means "stop". Clear All" and yellow means "Caution".