信号機の色
Traffic Light Colors
Traffic Light Colors
信号機の色は世界共通です。
Traffic light colors are based on a universal standard.
Traffic light colors are based on a universal standard.
国際照明委員会（CIE）によると、信号機に使える色は「赤・黄・緑・青・紫・白」の6つですが、我々は大抵「赤・黄・青緑」を使います。
According to the International Commission on Illumination (CIE), colors that can be used for traffic lights are red, yellow, green, blue, purple or white, but we only use red, yellow and blue-green in most cases.
According to the International Commission on Illumination (CIE), colors that can be used for traffic lights are red, yellow, green, blue, purple or white, but we only use red, yellow and blue-green in most cases.
青（緑）信号は完全に緑色に見えるかもしれませんが、実は青緑であることが多いです。
Although a green light might look completely green, the actual color is usually blue-green.
Although a green light might look completely green, the actual color is usually blue-green.
我々の目は緑色を敏感に感じるようになっているので、青緑色が完全に緑に見えるのです。
Since our eyes are sensitive to green, we view the blue-green light to be green light.
Since our eyes are sensitive to green, we view the blue-green light to be green light.
また、日本では青（緑）信号のことを、緑色に見えるにも関わらず、青信号と呼んでいます。
Also, Japanese people refer to a green light as “青信号” (blue light), though, we see it as green.
Also, Japanese people refer to a green light as “青信号” (blue light), though, we see it as green.
これは、日本では昔から緑から青にかけての色を全て「青」と表現していたことや、「赤」の対比が「青」とされてきたことに起因すると考えられています。
It is said that the reason is that we represented all colors from green to blue using only the word “blue,” or we thought the contrast of red is blue.
It is said that the reason is that we represented all colors from green to blue using only the word “blue,” or we thought the contrast of red is blue.
