For two women in the United Kingdom， mysterious vision problems that happened only at night or early in the morning turned out to have a rather innocuous cause： looking at a smartphone in the dark.

In the first case， a 22-year-old woman told her eye doctor that she had trouble seeing out of her right eye at night while she was in bed. These episodes happened multiple times a week for a year. Each time， she said she could only see the outlines of objects with her right eye， although her vision was fine in her left eye， and in both eyes the following day.

In the second case， a 40-year-old woman told doctors that she couldnt see out of one eye when she woke up in the early morning， before sunrise. This vision problem lasted about 15 minutes， and happened on and off for six months.

In both cases， doctors later discovered that these vision problems happened only after the women had viewed their smartphones for several minutes， while lying on their side in bed.

The doctors hypothesized that these problems happened because the patients， without realizing it， were looking at their phone with just one eye， with the other eye blocked by a pillow when they were lying down. In this situation， one eye （blocked by the pillow） becomes adapted to the dark， while the other eye （looking at the smartphone） is adapted to the light， the doctors said. When the smartphone is turned off， the light-adapted eye is perceived to be “blind”， until it also adjusts to the dark， the doctors said.

The doctors also tried their own experiment by looking at their smartphones with one eye in the dark， and found that their vision was considerably reduced in one eye， and took several minutes to recover.

對(duì)于英國(guó)的兩位女士，只在夜晚或者是早上出現(xiàn)神秘的視力問(wèn)題，結(jié)果是由一個(gè)相當(dāng)無(wú)傷大雅的原因引起的：那就是在黑暗中看智能手機(jī)。

在第一個(gè)案例中，一位22歲的女士告訴她的眼科醫(yī)生，她的右眼在晚上躺在床上的時(shí)候看不清。這些現(xiàn)象在一年之中每周要發(fā)生很多次。她說(shuō)，每次她的右眼只能看見(jiàn)物體的輪廓，盡管她的左眼視力良好，而第二天兩只眼睛的視力也良好。

在第二個(gè)案例中，一位40歲的女士告訴醫(yī)生說(shuō)，她在早上起床即日出之前，其中一只眼睛看不見(jiàn)。這種視力問(wèn)題持續(xù)大約15分鐘，六個(gè)月之內(nèi)斷斷續(xù)續(xù)地發(fā)生。

在兩個(gè)案例中，醫(yī)生后來(lái)發(fā)現(xiàn)這些視力問(wèn)題都僅僅發(fā)生在這兩位女士躺在床上持續(xù)幾分鐘看智能手機(jī)之后。

醫(yī)生假定，這些問(wèn)題的發(fā)生是因?yàn)椴∪嗽诤翢o(wú)意識(shí)的情況下用一只眼睛看手機(jī)，而另外一只眼睛在躺著的時(shí)候被枕頭所遮擋。醫(yī)生說(shuō)，在這種情況下，那只（被枕頭遮擋的）眼睛已經(jīng)習(xí)慣了黑暗的環(huán)境，而另外一只（看智能手機(jī)的）眼睛卻習(xí)慣了光亮。醫(yī)生說(shuō)，當(dāng)智能手機(jī)關(guān)掉后，那只適應(yīng)光亮的眼睛就被認(rèn)為是“盲的”，直到它也習(xí)慣了黑暗。

醫(yī)生自己也做了實(shí)驗(yàn)，在黑暗中用一只眼睛看智能手機(jī)，結(jié)果發(fā)現(xiàn)這只眼睛的視力大大下降，而且需要幾分鐘的時(shí)間來(lái)恢復(fù)。