Perhaps you’ve heard of the dangers of exposure to blue light. What exactly is this? Sunlight is comprised of red, orange, yellow, green, blue, indigo and violet light. When they combine, a white light results, each with different energies and wavelengths. Rays on the red end feature longer wavelengths with less energy. On the opposite end, blue rays feature shorter wavelengths with more energy. Light that looks white may have a big blue component, which exposes the eye to more wavelengths from the blue end of the spectrum.
Do you know what the largest source of blue light is? You guessed it, sunlight. But there are several other sources, including:
- Fluorescent light
- Compact fluorescent light bulbs, or CFL
- LED light
- Flat screen LED televisions
- Smart phones, computer monitors and tablet screens
The blue light exposure you get from screens is small compared with the amount of exposure you get from the sun, but it is there nonetheless. The long-term effects of screen exposure are concerning, due to the close proximity of the screens as well as length of time we spend looking at them. According to an NEI-funded study found on Prevent Blindness, children’s eyes absorb more blue light from digital device screens than adults.
Benefits of Blue Light
Blue light is necessary to maintain good health. It:
- Increases alertness, assists with memory and cognitive function, and enhances mood.
- Regulates circadian rhythm, which is your natural wake and sleep cycle. Too much exposure to blue light in the later night time hours (via smart phones, tablets, and computers) has a tendency to cause disturbances to the wake and sleep cycle, resulting in problems sleeping as well as daytime tiredness.
- Not enough exposure to sunlight can affect the growth and development of children’s eyes and vision. In fact, a deficiency in blue light exposure has been found to contribute to an increase in nearsightedness.
The Dangers of Blue Light
Nearly all visible blue light passes through the cornea and lens to reach the retina, affecting vision, and with the ability to prematurely age your eyes. Too much exposure to blue light can lead to:
- Digital eyestrain: Blue light decreases contrast, resulting in digital eyestrain. This happens when we stare at computer and tablet screens for too long. It can be caused by fatigue, dry eyes, poor lighting, or your position in front of the computer. Sore or irritated eyes and difficulty focusing can result.
- Retina damage: Continued exposure to blue light over time may result in damaged retinal cells and cause vision problems such as age-related macular degeneration.
There are a few things you can do to reduce eyestrain as a result of blue light, such as by limiting screen time, using screen filters, using computer glasses with yellow-tinted lenses, and wearing anti-reflective lenses to reduce glare and increase contrast.
Contact us at 302-239-1933 if you have symptoms of too much blue light exposure, or eyestrain.