Vision is the sense most heavily relied on by modern, technological society. Hearing may come in as a close second, but even without a sense of hearing, we could still navigate most electronics. Without our eyes, that becomes a laborious task. But what, exactly, are the screens we look at so much, doing to our eyes?
Blue Light Damages the Retina
Those glowing flat panes, held mere inches from our face, emit a powerful light that can, opticians say, lead to permanent eye damage. Much of the light that comes out of a screen is blue-violet. Studies show that, over time, too much exposure to blue-violet light can injure the retina. Retina damage can lead to macular degeneration, the most common cause of geriatric blindness.
Another source of eye injury is the microwave radiation emitted by cell phones. In an Israeli study, the lenses of calves (which strongly resemble humans) were exposed to the heat and the microwave level emitted by a cell phone. After two weeks, the cells showed signs of damage that limited their ability to focus light. Some had also irreversibly bubbled, a precursor to developing cataracts.
Eye Movement Saccades
A related problem is that when we focus on our screen tiny eye movements called saccades are disrupted. Saccades deliver refreshed visual information to the brain and blinking momentarily disrupts the saccade. So, when we need to focus our vision, gazing at our tablet, the blink rate slows so that we can continue the saccades without interruption. And in turn, when blink rate slows, the protective tear film covering the surface of the eye begins to deteriorate. The tear film not only keeps our eyes moist, but brings nourishment and removes waste. The end result is dry eye syndrome and red, irritated, tired eyes.
Not only that, but our blink rate is reduced significantly further contributing to dryness. Normally we blink about 18 times a minute, but on electronic devices, we blink only about 6 to 9 times a minute or less.
The average adult spends seven hours a day in front of a screen, and twenty-somethings check their cell phones about 32 times a day. The technology is too new to know how all that time will add up in later life, when our senses deteriorate anyway. Further research is needed to clarify potential risks.
In the meantime, to be on the safe side, opticians recommend turning down screen brightness and decreasing screen time when possible. Heavy users can also purchase a screen cover to decrease exposure. Avoid staring at a bright screen in dark lighting conditions, such as checking messages on your cell phone in a dark bedroom. Taking breaks, remembering to blink and attention to exercise, diet and proper supplementation can also help to prevent eye damage from screens. Check out our tips for avoiding eyestrain for laptops and desktop computers. These points are also important for all mobile device users.