电影中的海盗往往都蒙着一只眼，你可能会奇怪为什么海盗的眼睛都受伤了，实际上，戴眼罩只是为了让眼睛看得更清楚。

People may assume pirates wore eye patches just to look totally badass. But the eyewear most likely had nothing to do with a missing eye, and everything to do with being able to see—specifically, above decks and below them.

人们可能以为海盗戴眼罩只是为了看上去更像坏蛋。但是大多数海盗戴眼罩不是因为少了一只眼睛，而是为了让眼睛看得更清楚，确切地说，是在甲板上和船舱中都能看清。

Jim Sheedy, a doctor of vision science and director of the Vision Performance Institute at Oregon’s Pacific University, told the Wall Street Journal that while the eyes adapt quickly when going from darkness to light, studies have shown that it can take up to 25 minutes for them to adapt when going from bright light to darkness.

美国俄勒冈州太平洋大学视力表现研究所主任、视觉科学医师吉姆·希迪告诉《华尔街日报》，从黑暗环境走入光亮环境中，眼睛会快速适应，但是研究显示，明暗切换时眼睛的适应时间最长可达25分钟。

Pirates frequently had to move above and below decks on their ships, from daylight to near darkness, and Sheedy says the smart ones “wore a patch over one eye to keep it dark-adapted outside.” When the pirate went below decks, he could switch the patch to the outdoor eye and see in the darkness easily (potentially to fight while boarding and plundering another vessel).

从早到晚，海盗需要频繁地在轮船甲板上下穿梭，希迪指出，聪明的海盗会“在一只眼睛上蒙上眼罩，让其适应黑暗”。当海盗进入甲板时，他会将眼罩移到刚才在甲板上用来看东西的那只眼睛上，从而可以很容易地看清黑暗环境中的东西。（这意味着海盗在登上另一艘船只抢劫时可以随时进入战斗状态。）

Though there are no first-person sources from history that state this as fact, there’s no question that keeping one eye dark-adapted works. MythBusters tested this hypothesis in their pirate special in 2007 and determined that it was plausible.

尽管关于这个说法在历史上没有直接佐证，但是蒙上一只眼无疑是有效的。《流言终结者》曾经在2007年的海盗特别节目中测试了这一猜想，并确定这是可行的。

Even the FAA recommends that “a pilot should close one eye when using a light to preserve some degree of night vision.”

就连美国联邦航空管理局也建议，“在开灯时，飞行员应该闭上一只眼来保持一定程度的夜视力”。

英文来源：Mental Floss

翻译&编辑：丹妮