Do photochromic (transition) lenses filter blue light? Yes, but blue light filtering is not the primary reason people use photochromic lenses.
Most people buy photochromic lenses to ease the transition from artificial (indoor) to natural (outdoor) lighting. Because photochromic lenses have the ability to darken in the sunlight while providing UV protection, they eliminate the need for prescription sunglasses.
Plus, photochromic lenses have a third benefit: They filter blue light — both from the sun and from your digital screens.
Photochromic lenses filter blue light from screens
Are photochromic lenses good for computer use? Absolutely!
Although photochromic lenses were designed for a different purpose, they do have some blue light filtering capabilities.
While UV light and blue light are not the same thing, high energy blue-violet light is next to UV light on the electromagnetic spectrum. While most exposure to blue light comes from the sun, even inside a home or office, some blue light is also emitted by your digital devices.
Glasses that filter blue light, also called “blue light-blocking glasses” or “blue blockers”, may help improve visual comfort during long periods of computer work.
Photochromic lenses are designed to filter some of the highest energy level on the light spectrum, which means they also filter some blue-violet light.
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Blue light and screen time
Blue light is part of the visible light spectrum. It can be divided into blue-violet light (about 400-455 nm) and blue-turquoise light (about 450-500 nm). Blue-violet light is the high-energy visible light and blue-turquoise light is lower energy and what impacts sleep/wake cycles.
Some research on blue light suggests that it impacts retinal cells. However, these studies were conducted on animals or tissue cells in a laboratory setting, not on human eyes in real-world settings. The source of blue light was also not from digital screens, according to the American Association of Ophthalmologists.
Any long-term impact on the eyes from high-energy light, such as blue-violet light, is believed to be cumulative — but we don’t know for sure how prolonged exposure to blue light can impact us.
Clear blue-light glasses are designed to filter blue-violet light, not blue-turquoise light, so they won't impact the sleep-wake cycle. In order to filter some blue-turquoise light, a darker amber tint is needed.
Should I get photochromic lenses?
Photochromic lenses have many benefits, particularly because they function as both glasses and sunglasses. Because they darken when exposed to ultraviolet light from the sun, photochromic lenses provide glare relief as well as UV protection.
In addition, photochromic lenses filter some blue light from digital screens and sunlight. By reducing the effects of glare, photochromic glasses can contribute to a more comfortable user experience.
READY TO PROTECT YOUR EYES FROM UV? Shop for photochromic lenses at an eyewear retailer near you.