To confirm this, Omar Mahroo, an ophthalmologist at Moorfields Eye Hospital did an experiment. He went in a dark room and with one eye covered, gazed at a smartphone for 20 minutes before turning off the screen. “It did actually feel quite strange,” he says of his self-experiment. “It would be very alarming if you didn’t know what was going on.”
Then, he connected himself to a device that measured the current flowing in the photoreceptors in his retinas using electrodes. And sure enough, after flashes of dim light, the retina that had been exposed to the screen took longer to adjust to new light settings.
So does this mean we shouldn’t use our phones in the dark?
Of course not, but we should always ensure to use both eyes when looking at your smartphone screen, especially in the dark.
H/T : The Guardian