How to Keep Screens from Ruining Your Vision? 如何防止屏幕损害视力？

Laboratory studies have shown that prolonged exposure to high-intensity blue light damages retinal cells in mice. But epidemiological studies on real people tell a different story.

实验室研究表明，长时间暴露在高强度的蓝光下会损伤小白鼠的视网膜细胞。但是以真人为研究对象的流行病学研究却有不同的发现。

So， why the disconnect between blue light’s effects on rodent eyes and human eyes？

那么，为什么蓝光对啮齿动物的影响，与其对人眼的影响会不同呢？

Human eyes are different than rodent eyes. We have protective elements， such as macular pigments and the natural blue-blocking ability of the crystalline lens. These structures absorb blue light before it reaches the delicate retina.

人眼和啮齿动物的眼睛不同。我们人眼有保护性成分，如黄斑色素以及天然防蓝光的晶状体。这些结构能在蓝光到达脆弱的视网膜之前就把它吸收掉。

Just because blue light isn’t harming your retina doesn’t mean your electronic devices are harmless. Because of its wavelength， blue light does disrupt healthy sleep physiology.

仅仅因为蓝光不会伤害你的视网膜，并不意味着你的电子设备就没有害处。蓝光的波长导致它确实会扰乱健康睡眠的生理规律。

Mounting evidence suggests that screen time before bed increases the time it takes to fall asleep. It also robs you of restorative rapid-eye-movement sleep， dulls focus， and diminishes brain activity the next day.

越来越多的证据表明，睡觉前看屏幕会增加入睡时间。它还会让你无法完成恢复精力的快速动眼睡眠，让你在第二天无法集中注意力，大脑的活跃度下降。

There are ways to make your screen viewing more comfortable and more conducive to sleep.

这里有一些方法能让你看屏幕时更舒服，并降低其对睡眠的影响。

First， turn off your electronic devices before bed. Outside of the bedroom， when you do look at your screens， lower the brightness.

首先，睡觉前关掉你的电子设备。在卧室之外的其他场所看屏幕时，要调低屏幕亮度。

Second， follow the “20-20-20” rule. The American Optometric Association defines this rule as taking a 20-second break every 20 minutes to look at something 20 feet in the distance. This will allow your eyes to blink and relax.

其次，遵循“三个20”原则。美国验光协会将其定义为：每隔20分钟休息20秒，并注视20英尺（6.1米）外的物体。这会让你的眼睛有眨眼和放松的机会。

Third， use lubricating eye drops before extended computer use. This tactic will reinforce the body’s natural tears and keep the eye’s surface hydrated.

再次，在长时间使用电脑前点滴润滑型眼药水。这个方法能补充人体的天然泪液，使眼球表面保持湿润。

Word Bank

retinal /'retɪnl/ adj. 视网膜的

rodent /'rəʊdnt/ n. 啮齿动物

pigment /'pɪɡmənt/ n. 色素；颜料

conducive /kən'djuːsɪv/ adj. 使容易（或有可能）发生的

Fresh air is conducive to health.

lubricate /'luːbrɪkeɪt/ v. 給……上润滑油；上油于