Natural blue light is all around us. It's what makes the sky look blue. Natural blue light regulates your sleep and wake cycles. It also boosts alertness, elevates your mood, and increases feelings of well-being.
Artificial blue light, found in things like computers and flat screen televisions, LED lights and energy-efficient light bulbs, can be harmful to your eyes. The backlit displays on cell phones, e-readers, and laptop computers emit high amounts of very strong blue light waves.
Too much blue light can take a toll on your health. Within the visible light spectrum, blue light has a shorter wavelength and higher energy, which is harder for our eyes. Because these waves are shorter, they appear to flicker more than longer, weaker wavelengths.
Flickering is the flashing effect that happens when the LED backlight controller of a monitor adjusts the brightness levels during display refreshing. This causes eye fatigue without you even noticing. Take a look at the light spectrum to see how blue light works.
A Harvard medical study states that "High Energy Visible (HEV) blue light has been identified for years as the most dangerous light for the retina. After chronic exposure, one can expect to see long range growth in the number of eye diseases including macular degenerations, glaucomas, and retinal degenerative diseases."
Our eyes have natural filters but they're not enough to protect against the over-exposure of blue light. Our skin, nails, hair and eyes all contain melanin, the body's natural "sunscreen" which absorbs harmful UV and blue light rays.
But as we age, we lose melanin; by around age 65, half of our natural protection is gone. That makes our eyes more susceptible to damage from both UV rays and blue light which can more deeply penetrate the retina leading to macular degeneration.
More than half of U.S. adults – 60 percent – spend a minimum of six hours a day, every day on phones, tablets and computers, so it's important to practice good habits to keep your eyes safe from blue light.
Because we use our electronic devices so regularly, we are gradually being exposed to more sources of this light for longer periods of time.
1. Use the 20/20/20 Rule—Follow the 20-20-20 principle. This means, look away from your computer or digital device every 20 minutes for 20 seconds about 20 feet away. This helps your eyes refocus and avoid computer eye strain.
2. Invest in Blue Light Filtering Lenses—Get fitted for blue light filtering lenses to block the penetration of blue light from computers and digital devices. They're available for prescription and non-prescription glasses.
3. Use Good Ambient Lighting—Keep balanced lighting around your computer work area to avoid high contrast and reduce glare to avoid computer eye strain. Avoid using a device in complete darkness.
4. Avoid using digital devices an hour before trying to sleep—Don't take phones and tablets to bed. The blue light from your phone's display is more likely to keep you awake than the incandescent lamp on your bedside table.