Blue Light/High-Energy Visible (HEV) Light and Your Eyes
According to recent studies, 60% of people spend as much as 6 hours a day in front of a digital device whether it is a computer, tablet, smartphone or other gadget. All of these devices emit blue light or high-energy visible (HEV) light, which has been shown to be a cause of computer vision syndrome, sleep disruptions and possibly other potential dangers to the eyes. Blue light radiation is also emitted from television screens, electronic devices. fluorescent and LED lighting and yes, even the sun.
What is Blue Light?
Emitted from the sun, blue light is naturally occurring in the world around us. On the spectrum of visible light (light that humans can see), blue light has the highest energy and the shortest wavelength. It is also sometimes known as blue-violet or violet light, which is where ultraviolet (UV) light rays, that are just beyond our human perception, get their name. Much like ultraviolet light, blue light has both dangers and benefits to our health, particularly to our eyes.
What are the Potential Dangers of Blue Light?
Research is still being undertaken to determine the long-term effects of blue light or high-energy visible (HEV) light emission, however it has been shown in multiple studies is that blue light could be a cause of computer vision syndrome (CVS) and sleep disruptions.
The high energy and shorter wavelengths of blue or HEV light emit a less consistent flow of light, creating a glare or flickering that can cause eye strain. Because sharpness and visual contrast are affected by this, the eyes have to work harder to see clearly. After extended periods of time the glare or flicker can result in headaches, blurred vision, dry eyes and mental and physical fatigue.
Natural blue light in the atmosphere is known to help regulate the body’s circadian rhythm (which controls your sleep cycles), to boost your mood and level of alertness and to improve memory and cognitive function. However, prolonged exposure to artificial sources of blue light has been shown to reverse these positive effects, causing disruptions in the circadian rhythm which affects sleep, as well as an increased risk of depression. Studies show that using a digital device before bedtime can negatively impact the duration and quality of your sleep.
Researchers at Harvard University have shown that over time, prolonged exposure to blue light can cause damage to the retina at the back of your eye, which may lead to age-related macular degeneration (AMD) and possibly other serious health and vision problems. AMD is a leading cause of vision loss and low vision.
How Can You Protect Yourself from Blue Light Emissions?
As the dangers of blue light from digital devices emerge, more and more options are becoming available to protect your eyes. The eyes have very limited natural ability to block out blue light radiation so we need to be aware of blue light exposure and how to minimise it.
Computer glasses with blue-blocking lenses, coatings and filters are a good solution for those working on a computer for long periods of time each day. You can also add anti-glare coatings with blue light protection to your regular eyeglass and sunglass lenses. Additionally, there are filters available for devices such as computers, smartphones and tablets, to reduce the amount of blue light radiation that can reach your eyes.
The easiest way to reduce blue light exposure is to take frequent breaks when working on a computer and to reduce screen time overall, but this might not be sufficient to alleviate the harmful effects of blue and HEV light on the eyes.