Skip to Main Content

The Damaging Effect of Blue Light

Virtually every digital device, as well as light emitting fixtures and appliances including fluorescent lamps, has light-emitting diodes (LED) that radiate blue wave-length light.

Emerging research suggests cumulative and constant exposure to the blue light emitted from backlit displays can damage retinal cells.

Blue light penetrates deeper into the eye compared to ultraviolet light, so the exposure may damage the retina by exposing the eye to hidden spikes in intensity. The wavelengths within the blue-violet portion of the light spectrum that are considered potentially most harmful to retinal cells range from 415 to 455 nanometers, and most of our devices emit a high level of blue light, typically around the wavelength starting at 400 nm.

Cumulative blue light exposure is linked to slow degeneration of the retina, which could accelerate long-term vision problems such as age-related macular degeneration (AMD) and cataracts.

While this high-energy light is necessary for aiding cognitive functions, such as alertness, memory and emotion regulation, it can also disrupt sleep by suppressing the natural release of melatonin. According to the VisionWatch survey, more than 75 percent of American adults report checking their digital devices in the hour before going to sleep. This eye exposure before bedtime has been shown to disrupt sleep patterns by increasing alertness in the brain.

Computer eyewear is available with blue light filtering capabilities that reduce the effects of this wavelength on circadian rhythm—which can hinder a good night’s sleep. Researchers examined the effect of blue light blocking glasses on teenagers who use LED screens before bed. They found that the glasses significantly weakened the LED-induced melatonin suppression and decreased alertness brought on by blue light before bedtime.