But meanwhile, “the ergonomics of reading screens and the lack of blinking when we stare at them play a big role in eye fatigue” as well. What’s more, different devices present different problems:
E Ink has a very low contrast ratio. Although it can offer an excellent reading experience in bright sunlight, the screens can become uncomfortable to use in dark settings because of the lack of contrast and backlighting on the screen.
LCD screens, meanwhile, have long struggled to offer good viewing angles for reading. Apple’s latest IPS LCD screens include extremely wide viewing angles, but the reflective glass on the screen could be a hindrance in brightly lit situations.
What’s more, a Los Angeles Times story by Mark Milian says reading from iPads or other light-emitting devices ….
… inhibits the body’s secretion of melatonin, say several sleep experts.If you’ve watched any late-night TV, you’ve no doubt heard the term thrown around in commercials for sleeping pills. Melatonin signals are sent through the brain as a response to darkness, telling the body to prepare to shut down for the night.
Light-emitting devices, including cellphones and yep, the iPad, tell the brain to stay alert. Because users hold those devices so close to their face, staring directly into the light, the effect is amplified compared with, say, a TV across the room or a bedside lamp, said Frisca Yan-Go, director of the UCLA Sleep Disorders Center in Santa Monica.
… Yan-Go was eager to point out the advantages of books over e-readers. Paper books are often lighter; they can be dropped when you doze off holding them; and if they get wet, it’s not the end of the world. And they won’t mess with your sleep cycle.
So what’s the most eye-friendly way to read? A Wall Street Journal report by Geoffrey A. Fowler says, eh, well, who knows?
So far, there’s little scientific evidence about which screens are better for the eyes. Ophthalmologists say there isn’t really much of a difference between how the eye works with either e-paper or back-lit screens. Neither could damage the eye and neither of these modern screens flicker like old-fashioned TVs.
Michael Marmor, a professor of ophthalmology at Stanford Medical School who has a Kindle at home, says neither technology offers inherent advantages. Reading with both kinds of screen could cause eyestrain because it has relatively little to do with the function of the eye, he says. Eyestrain is caused by placing too much stress on the brain and body by doing one thing for too long. The only solution for eyestrain is taking more regular breaks.