Blue Light Filters? What is Blue Light and Why is it Considered Harmful?
What is Blue Light?
Blue Light, also known as high-energy visible light (HEV), is a colour in the visible light spectrum that can be seen with human eyes. Wavelengths of light are measured in nanometres and can be visible and non-visible to the human eye, the shorter the wavelength the higher the energy. Blue light is a short wavelength, which means that it produces higher amounts of energy.
Our eyes cannot filter out blue Light like other colours of light on the spectrum, which can pose a concern for our eyes and overall health.
Where am I exposed to Blue Light?
We are constantly exposed to blue light, with the largest source of blue light coming from sunlight. Blue light is also emitted by laptops and computer monitors, smartphones, digital devices, fluorescent, and CFL bulbs. But it’s the blue light that is emitted from our digital devices which is of particular concern because of how close we hold our devices and the length of time that we are on our devices.
With screen time being on the rise over the past 20 years, studies show that we are exceeding 13 hours a day on scene devices. Many people experience eye discomfort and vision problems when using digital devices for extended periods of time.
Common symptoms of digital eye strain are:
- Dry irritated eyes
- Headaches
- Eye strain
- Blurred vision
Sleep and Blue light
There have also been studies that have shown that the use of digital devices at night may suppress the release of melatonin, the hormone which is responsible for making us feel drowsy. Too much blue light exposure from digital screens at night may cause:
- Impact to circadian rhythms (the natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours)
- Trouble sleeping
- Reduce alertness the next day
- Waking up during the night
What does this mean for the long term?
Studies have shown evidence that our eyes are susceptible to blue light exposure, and that over a period continued exposure may increase the likelihood of vision problems.
Children are likely to be more vulnerable to blue light as their adolescent eyes don’t have the same blue light filtering ability as adults. Along with this children often hold digital devices closer to their eyes, increasing the intensity of the high-energy visible light reaching their eyes.
What can we do to reduce our exposure?
Since we can not completely avoid our exposure to blue light, we can take other steps to help reduce our exposure. This may include:
- Eye Exam: Talk to an Optometrist about options about ways to protect your eyes.
- Screen Time: Try to decrease the amount of time spent in front of these screens.
- Screen Protectors: Screen Protectors with advanced blue light filtration are available for smartphones, tablets, laptops and computer monitors.
- Built-In Technology: Many laptops and monitors now have technology designed into the hardware, which helps reduce blue light emissions.
- Follow the 20-20-20 Rule: For every 20 minutes spent looking at a screen, a person should look at something 20 feet away for 20 seconds.
- Blue Light Protective Coatings: There are now several different options for blue light blocking coatings which are available on almost all prescription glasses, with blue light filtering contact also now available.
Zeiss have built-in blue light blocking properties to their BluePro lens range, blocking out the harmful Blue UV while remaining clear, unlike traditional yellow lens blue light glasses.
There is also options such as Baxter Blue which are a non-prescription Blue light glasses range. They are available in a range of styles for all ages to help reduce our daily exposure to blue light. (Available in-store)
For more information check out these links below:
https://www.zeiss.com.au/vision-care/eye-care-professionals/lenses/coatings-technologies/blue-light-blocking-lens-technology.html
https://www.baxterblue.com.au/pages/digital-eye-strain
References
- Consolidated Blue Light Research, available at eyesafe.com/research
- Blue light has a dark side – Harvard Health
- Digital Eye Strain, The Vision Council
- Chang AM, et al. Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proceedings of the National Academy of Sciences of the United States (PNAS). January 2015. 112(4): 1232-1237. [Accessed December 3, 2019]
- Behar-Cohen F, et al. Light-emitting diodes (LED) for domestic lighting: any risks for the eye? Progress in Retinal and Eye Research. 2011 Jul;30(4):239-57.)
- 2020 UnitedHealthcare and Eyesafe Screen Time Survey of 400 Eye Care Professionals
- 2022 UnitedHealthcare and Eyesafe Screen Time Survey of 484 Parents and 408 Educators
- www.eyesafe.com
