Joel Hunter, MD Refractive Surgeon, Hunter Vision Updated 01/11/21 11:00 AM
You’ve seen blue light blocking glasses. Blue can’t get through the lenses, so the lenses have the yellow or orange color of white light minus blue light. You’ve seen them on sharp shooters, some athletes, some gamers, and Steven Seagal. Why the hype? What’s wrong with blue light?
There’s nothing inherently bad about blue light, just like there’s nothing inherently wrong with sand at the beach. But similar to that sand, having it in the wrong place at the wrong time can get pretty uncomfortable. Our eyes evolved to see all the colors, but they didn’t evolve to see all the colors all the time. There are two ways that fact impacts our modern life and the screen time that comes with it.
First, blue/violet light has the shortest wavelength of all the visible light. That’s why it’s always on the underside of a rainbow, short wavelengths get diffracted (light scattered) the most. This happens with uneven mist in the air (causing a rainbow) and uneven tears coating your eye (causing glare).
Unlike rainbows, computer screens make it easy to miss the glare emanating from the surface of your eye. It’s usually not terrible and incapacitating, just a little annoyance for your eyes. For a few minutes, it doesn’t matter. But hour after hour for days on end, that adds up. It can cause a strained and tired feeling that builds over time. You may not even think, “I don’t want to look at this computer screen anymore.” Usually that thought is camouflaged as, “I don’t want to work anymore today.”
The second problem with wrong place / wrong time blue light happens with our natural circadian rhythm. It’s crazy to think about, but no one saw blue light after sunset until about 140 years ago. So for 99.9% of human existence, it was a safe bet for our brains to use “no blue light” as the sign to start getting sleepy and go to bed. But now, we have screens blasting blue light into our eyes and brain way past sunset.
This suppresses the release of melatonin, our body’s natural starter pistol for the race to get to bed. It’s not surprising that about ⅓ of people have sleep problems. Have you ever been camping and, after dark, thought, “it must be 11 pm” only to find out it’s like 8:30? I have! That’s because we are getting a taste of the natural sleep/wake cycle possible when we eliminate blue light after dark.
For both of these issues, blue light blocking glasses can really help. There are specific kinds designed to help more with computer light or more with night time blue blocking. If you’re wondering how to get a pair of glasses for the computer, it may be worth visiting an eye doctor to see if a prescription for computer glasses also helps. If you don’t need a prescription, or you’re just looking for something to help with after-dark blue light, then you can find lots of options online.
Are blue light blocking glasses necessary? No. They’re not essential. Can they make life easier in some specific ways? Absolutely. Just ask 90s action star Steven Seagal. (Disclaimer: don’t actually do that because there’s a chance of getting karate chopped.)