What is Blue Light?
Blue light, also know as high-energy visible (HEV) light, is a color in the visible light spectrum that can be seen by human eyes. These wavelengths of visible and non-visible light are measured in nanometers (nm), and, in general, the shorter the wavelength, the higher the energy. Blue light is a short wavelength, which means it produces higher amounts of energy.
Unlike other forms of light, the eyes cannot effectively filter blue light, so more can pass through the eye to the retina. Blue light produces both benefits and concerns for our eyes and overall health.
Sources of High-Energy Blue Light
We are exposed to blue light on a near constant basis. The largest source of blue light is sunlight, but is also emitted by laptops and computer monitors, smartphones, tablets, TV, fluorescent and CFL bulbs.
Our blue light exposure from digital devices are of particular concern because of the close proximity of the screens, length of time we use our devices, and the cumulative impact of using devices every day.
What are the Risks?
Eyes and Body
Screen time has been on the rise for the last 20 years and is now exceeding 13 hours per day.1 According to the Vision Council, many people experience eye discomfort and vision problems when using digital devices for extended periods.
As many as 65% of Americans report experiencing symptoms of digital eye strain, which may include symptoms of:
- Eye strain
- Blurred vision
- Dry, irritated eyes
The use of digital devices at night may suppress the release of melatonin, the hormone responsible for making us feel drowsy. Too much blue light exposure from viewing screens at night may result in:
- Impact to our circadian rhythms
- Trouble sleeping
- Waking up during the night
- Reduced alertness the next day
- Health Risks High Energy Blue Light
There is evidence that the eye is susceptible to blue light exposure, and that over a period of time, cumulative exposure may increase the likelihood of vision problems. More research is needed to ascertain long-term impacts to the retina and any links to chronic vision problems.1
Children may be more vulnerable because their eyes don’t have the same blue light-filtering ability that adult eyes have. Children also tend to hold devices closer to their eyes, increasing the intensity of high-energy visible blue light reaching their eyes.2
Children’s developing eyes allow more blue light to pass to the back of the eye.
Concerns about Blue Light
Screen time and blue light exposure have been raised as a growing public health concern. Doctors, educators, employers and parents agree that there are potential risks from overexposure. According to a recent survey, doctors believe the following are symptoms of excessive screen time and blue light exposure:
- Sleep disruption (79%)
- Tired/ sore eyes (77%)
- Dry eyes (70%)
- Headaches (56%)
- Reduced productivity (46%)
- Reduced concentration (43%)