What is blue light?
“Blue light” —the type emitted by computers, cell phone display screens, and fluorescent and LED lights— is defined as the portion of ultraviolet (UV) light-ray spectrum in the 400-490 nanometer range. These shorter wavelengths of visible light have high energy and, as a result, high-absorption rates by the retina.
They also cause drusen —a precursor to macular degeneration. This condition has typically been age-related and is the number one cause of blindness in the United States in people age 50 and older. However, the increased exposure to digital devices is alarming, as it suggests that we may begin seeing symptoms of macular degenerations beginning at earlier ages.
These risks of exposure to blue light are not new. They are not only caused by the prevalence and convenience of digital devices but have always existed due to exposure to sunlight, especially in the Southern parts of the United States. Warnings over the years about the risks of skin-cancer-causing UV rays have led people to use sunblock protection and spend less time outdoors. But more time spent indoors often means more time spent online or staring at our digital screens and exposed to blue light.