We only have to look around to see how ubiquitous those cell phone screens are. How we're looking at those tiny screens, and where we place them might tell us something about our eyes.
It was just a few years ago, that the only electronic screens we looked at were in the workplace or in the home.
But now they're everywhere. Many of us work or read right on our cell phones.
Ben Jolly says he's reading something every hour.
"I do find myself on my phone more nowadays than a couple of years ago, cause how the phones have changed," he said.
"I had noticed that people holding cell phones very close, much closer than books and newspapers. That's what triggered me to see what distances they're actually reading at," he said.
That question resulted in a study which measured reading distances. On average, people read the printed page 16 inches away. But studying dozens of people, Dr. Rosenfield found that even though the font size was the same in both printed page and electronic page, the electronic page was read closer in.
"It's somewhere between 12 and 14 inches on average, and some people as close as 7 inches," he said.
And holding the electronic reading close in, puts extra demands on the eyes, says Dr. Rosenfield.
He says extra demands could mean eye strain, tired eyes and headaches. Good care when reading is to hold the phone a little farther away and to take frequent eye breaks from the screen.
"Look into the distance from time to time so the eyes get a chance to relax," he said.
Reading from cell phones is so new, no one has yet determined what the ideal distance is, but if you're holding it closer than the average 12 to 14 inches, it might be time to visit your eye doctor.
This study was published in the official Journal of the American Academy of Optometry.