Why do you use traffic lights to do traffic lights?
According to the optical principle, the red light of long wavelength, air penetration ability, and even more interesting than the other signal, so as to prohibit access signal, the use of green as the announcement signal, because the difference between red and green, it is easy to distinguish (red green blindness after all is one of the few)
Later, the parliament building in London before the traffic accidents often happen, so it was inspired from "red green" to "green" as traffic lights (December 10, 1868).
At the beginning of nineteenth Century, in the middle of the city of York, red and green represent different identities of women, such as women in red and Green said married, said unmarried.
When it comes to red and green in traffic signals, you have to look back at the origins of traffic lights
For people, the traffic lights are not unusual, but have you ever wondered why we see the traffic lights "traffic lights"
