半夜睡不着的时候，很多人都会拿起手机，刷微博或者看朋友圈。屋子里整体是一个黑暗的环境，如果看手机的时候侧躺着，主要用一只眼睛看手机，那么等你翻身平躺，把两只眼睛都睁开的时候，你会感觉到刚才看手机的那只眼睛什么都看不见。
Smartphone blindness happens when people lie on their side at night, with one eye against the pillow and the other staring at the smartphone screen. While one eye adjusts to the dark, the other eye gets used to the bright light of the high-resolution screen. But when they roll over and open both their eyes, the eye which has been staring at the screen cannot cope with the darkness of the room. Subsequently, with both eyes uncovered in the dark, the light-adapted eye is perceived to be “blind”.
人们晚上侧躺着看手机，一只眼靠着枕头，另一只眼盯着手机屏幕的时候会出现“智能手机眼盲症”。一只眼(靠着枕头的那只)适应了黑暗的环境，而另一只眼(看手机的那只)则适应了高分辨率屏幕发出的亮光。当你翻身把两只眼睛都完全睁开的时候，之前盯着手机屏幕的那只眼睛无法适应房间内黑暗的环境。结果，两只眼同时在黑暗环境中的时候，适应了光亮的那只就会出现“眼盲”的情况。
It usually takes several moments for the eyes to adjust, leading people to believe they are suffering from a severe problem.
通常，这种情况需要一段时间让眼睛来慢慢适应，有些人就会以为自己得了什么重病。
A similar condition known as digital eye strain may also appear after long hours of staring at computer screen or smartphone screen. The sympotoms may include eye dryness, blurry vision and persistent headache.
另外一种相似的症状叫“数码眼疲劳”，多半出现在长时间盯着电脑或手机屏幕之后，主要的症状有，眼干、视野模糊，以及长时间头疼。
缓解眼疲劳小贴士：
1. Blink more often.
多眨眼。
Blinking is very important when working at a computer; blinking moistens your eyes to prevent dryness and irritation.
看电脑的时候眨眼很重要，眨眼能够滋润眼睛，防止眼干和不适。
2. Adjust your computer display settings.
调整电脑显示设置。
Brightness. Adjust the brightness of the display so it's approximately the same as the brightness of your surrounding workstation.
亮度。将电脑显示的亮度调整到接近周围环境亮度的水平。
Text size and contrast. Adjust the text size and contrast for comfort, especially when reading or composing long documents.
字体大小和对比度。将字体大小和对比度调整到让眼睛舒适的水平，尤其在需要长时间阅读或处理文件的时候。
3. Take frequent breaks.
多休息。
To reduce your risk for computer vision syndrome and neck, back and shoulder pain, take frequent breaks during your computer work day.
为了缓解电脑视力症状以及颈、背、肩痛，在电脑前工作时要多停下来休息。