Using a cell phone doesn’t generally injure you, although as anybody who has to get through a pedestrian crosswalk can tell you, misusing it can sure go wrong. But using it at night might make you blind in one eye, at least for a while.
New York Magazine has the story of two women reporting blindness in one eye. They were otherwise completely healthy, their eyes checked out as normal, and the doctors were left confused. Finally they realized that both women were lying on their side and using their phones late at night and early in the morning, and it was their night-vision messing them up.
As we all know, your pupils get wider in darkness to admit more light and allow you to see. But if one of your eyes, say the right one, is blocked, and you look at a bright object with your left eye in total darkness, the right eye will adapt to darkness while the left eye won’t. So when you suddenly look away from your phone, and are plunged into darkness, your left eye will seem “blind” until your eyes adapt.
The solution, of course, is to only look at your phone with both eyes. Or, even better, don’t look at your phone at all: It’s been shown looking at your phone before bed leads to worse sleep. But if you absolutely must, use both eyes to do it.
(Via New York Magazine)