With more people using computers, tablets, phones and other devices, blue light has become more of a topic than ever before. Because this is a someone new topic and it’s still too new for researched white papers, we can only go off of what we know thus far. This Your Blue Light Questions Answered article by Optician Now has provided, in basic terms, what blue light can affect and what options are on the market for filtering out or blocking blue light
Digital Eye Strain
When viewing electronic devices, blue light lands before your retina (where you would get the clearest vision) which results in what is now termed digital eye strain. The Vision Council defines digital eye strain as “the physical eye discomfort felt by many individuals after two or more hours in front of a digital screen”.
The symptoms of digital eye strain can be broken down into three causes: proximity of the light source (digital device) to the eye, intensity of light from the source, and frequency and duration of exposure. In considering ways to alleviate symptoms, keeping these causes in mind can guide treatment recommendations.
Circadian rhythm can be thought of as regulating our sleep – wake cycle. Historically, human exposure to blue light at night was relatively low. Daytime exposure to blue light, would trigger our internal clock to suppress melatonin secretion, keeping us alert and awake. As evening would fall, lack of blue light would allow for secretion of melatonin with subsequent onset of sleep. However with advancements in technology, our evening exposure to blue light is at levels never before experienced by mankind. Electronic screens on our smartphones, tablets, and computers, as well as LED and CFL light bulbs, all emit blue light affecting ipRGC function, which plays a major role in synchronizing circadian rhythms to the 24-hour light/dark cycle.
Reducing the blue light wavelengths from devices
Glasses are more effective at filtering out blue light than changing the blue light settings on a screen. While the market is saturated with blue light blocking glasses, the majority can be broken down into the two most popular kinds: blue light filters and blue light blocking anti-glare coatings.
Blue light filter
- A filter within the plastic material of the lens that filters out a specific wavelength of blue light.
- These have a slight tint the lens but appears clear to most people.
- They can be worn as-is or you can have an anti-glare coating added to help with clearer vision since you won’t be straining to look through the glare on the lens.
Blue light anti-glare coating
- A modified mirror coating that is designed to increase blue reflections off of the lens to prevent it from entering the eye.
- These appear to have a noticeable purple-bluish reflection on the lens.
- The most common complaint of this coating is that people see the purple/blue lens when looking at you rather than being able to see your eye through the lens. This is most often noticed in photos and on video conference calls.
Extra tip: most light changing photochromic lenses have a blue light filter within them.
For computer use, which is better: a blue light blocking anti-reflective coating or a blue light filter?
A filter is always better because it actually filters. Blue blocking anti-reflective coating/modified mirror causes additional opportunities for the wearer that may be worse than the initial problem.