translation.en: And why this is interesting is that if you put on, say, a pair of safety glasses, that have two infrared dots in them, they are going to give the computer an approximation of your head location.
translation.zh: 它有趣的地方是 如果你带上一副保险眼镜， 眼镜上有两个红外发光点， 这两个红外发光点 可以让电脑知道你头部的大概位置。