人眼自身就具有藍(lán)光防護(hù)機(jī)制

Blue light before bedtime can make it harder to sleep, and the screens on phones, computers, and televisions emit plenty of blue light. This is all true. But if you're focused on blue light as a major problem affecting your sleep or your eye health, it's time to step back and get another perspective.

睡前接觸藍(lán)光會(huì)讓人難以入睡，而手機(jī)屏幕、電腦屏幕和電視屏幕都會(huì)發(fā)出大量藍(lán)光。這都是事實(shí)。但如果你認(rèn)為藍(lán)光是影響睡眠或眼部健康的主要原因，那也許是時(shí)候退后一步，換個(gè)角度思考了。

As Philip Yuhas, a professor of optometry, writes at The Conversation, blue light isn't a uniquely technological evil. It's part of sunlight, and your eyes are exposed to plenty of it all the time. You're fine.

驗(yàn)光學(xué)教授菲利普·尤哈斯(Philip Yuhas)在The Conversation新聞網(wǎng)上寫道，藍(lán)光并不止是技術(shù)帶來的弊端。它也是陽光的一部分，而眼睛長(zhǎng)時(shí)間處于陽光之下的你并沒有什么問題。

There are studies in mice that have found blue light can damage the eyes, but mice are nocturnal creatures whose eyes are different from ours. The pigments and the lenses of our eyes actually block blue light fairly well—so in a sense, we already have built-in blue blocking protection.

對(duì)老鼠開展的研究發(fā)現(xiàn)：藍(lán)光會(huì)對(duì)眼睛造成傷害，但老鼠是夜行性動(dòng)物，它們的眼睛與人類是不一樣的。實(shí)際上，人類眼睛中的色素和晶狀體可以很好的阻擋藍(lán)光——所以，從某種意義上講，人眼自身就具有藍(lán)光防護(hù)機(jī)制。

Adding more protection isn't likely to help, though. You can buy glasses and screen filters that block blue light, but Yuhas points out they are probably a waste of money: the products that my patients ask about do not block out much blue light. The leading blue-blocking anti-reflective coating, for example, blocks only about 15% of the blue light that screens emit.

但是，更多的防護(hù)措施不一定有用。您可以購(gòu)買防藍(lán)光眼鏡和防藍(lán)光貼膜，但尤哈斯指出這可能只是在浪費(fèi)錢財(cái)：患者咨詢的這些產(chǎn)品并不會(huì)阻擋太多的藍(lán)光。例如，主流防藍(lán)光減反射膜僅阻擋屏幕發(fā)出的15%的藍(lán)光。

You could get the same reduction just by holding your phone another inch from your face. Try it now and see if you notice a difference. No? Then it shouldn't surprise you that a recent meta-analysis concluded that blue-blocking lenses and coatings have no significant effect on sleep quality, comfort at the computer, or retinal health.

只要看手機(jī)的時(shí)候拿遠(yuǎn)一點(diǎn)，效果也是一樣的。試試看吧，有沒有什么不同?是不是沒有不同呢?或許你對(duì)下面這項(xiàng)結(jié)論也就不感到奇怪了——最近的一項(xiàng)整合分析總結(jié)道：防藍(lán)光鏡片和防藍(lán)光膜并不會(huì)對(duì)睡眠質(zhì)量、玩電腦的舒適度或視網(wǎng)膜健康造成顯著影響。

The American Academy of Ophthalmology doesn't recommend blue-blocking products, either. Instead, if you're concerned about your eye health or your ability to get to sleep on time, you already know what to do:

美國(guó)眼科學(xué)會(huì)也不建議使用防藍(lán)光產(chǎn)品。相反，如果您擔(dān)心自己的眼部健康或無法按時(shí)入睡，您其實(shí)已經(jīng)知道該怎么做了：

Put the screens away at bedtime. Read a book or find something else to do.

睡前不玩手機(jī)等電子產(chǎn)品?？磿?huì)兒書或做點(diǎn)其它事情。

While you're using screens, take a 20-second break every 20 minutes to look at something 20 feet away (the "20-20-20" rule).

每使用屏幕20分鐘，盯著20英尺遠(yuǎn)的地方看20秒(20-20-20護(hù)眼小技巧)。

If you get dry eyes when you look at screens for a long time, use eyedrops labeled artificial tears.

久盯屏幕后若眼睛干澀，可使用人工淚液緩解。