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Blue light glasses: what they are really worth

by laqi

At the optician's, the question comes up between choosing your frames and heading to the checkout.

“Would you like the blue-light filtering treatment?”

You spend your days in front of a screen, you don’t sleep all that well, so you say yes. It can’t hurt.

It probably doesn't hurt, indeed. But does it do any good? That’s where the studies get interesting.

A clarification before we begin: this article is written by laqi. We don’t sell glasses, but we do sell lights, and we have an opinion on the matter. We are sticking to the studies.

Blue-light blocking glasses: what the science says

In August 2023, the Cochrane Library, which is the reference for synthesizing medical trials, compiled 17 studies on blue-light blocking glasses, conducted on 619 adults. Their conclusions:

  • for eye strain from screen use, they may not provide any short-term benefit (low-certainty evidence);
  • for sleep, the effect is undetermined: three trials found an improvement, while three others found nothing;
  • for retinal protection, no study has measured it.

Anses had already reached a similar conclusion in 2019: the effectiveness of these lenses for protecting the retina is "highly variable," and for preserving the biological clock, it "is not proven today."

A filter that doesn't target the right blue

There is a simple reason for these disappointing results. Anses distinguishes between two types of blue: a deep blue, around 450-470 nanometers, which can damage the retina in high doses, and a turquoise blue, around 480-490 nanometers, to which the body's clock is most sensitive.

The cells that regulate the internal clock react primarily around:

480 nanometers.

However, the clear lenses sold for screens claim, according to their manufacturers, to filter mainly below 410 nanometers, or up to 450. The blue that the body clock tracks is largely missed.

It’s a bit like a screen door that stops flies but lets mosquitoes through. It does something, but not what is asked of it.

A team in Hong Kong verified this in 2017. According to their calculations, these clear lenses reduced the effect of light on melatonin, the hormone of the night, by only 5.8 to 15%. And more than 70% of the volunteers saw no difference compared to normal lenses.

What about orange or red lenses in the evening?

That is another story. Amber or red lenses cut out much more blue light, and in fact, a lot of light in general. One manufacturer claims their red "night" glasses have a visible light transmission of 29%. Essentially, you are wearing a dimmer switch on your nose.

A 2021 review deems these amber glasses promising for falling asleep faster in people with sleep disorders, shift work, or jet lag. For the general population, the evidence remains weak. And since they significantly darken your vision, they have no place on your nose while driving at night.

Models and their prices

A few examples, with prices noted on the manufacturers' websites on October 12, 2026:

  • Barner, Dalston model, clear lenses for screens: €59 for non-prescription lenses.
  • Horus X, Stockholm model, clear lenses: €59.90.
  • Horus X, Recovery range, red lenses for the evening: from €69.90 to €99.90. The manufacturer itself writes that evidence of better sleep in healthy adults remains debated.

The filtering percentages displayed on the boxes come from the manufacturers, based on color ranges they choose themselves. We found no independent measurements for these models. As for unbranded models from major platforms, it is impossible to know what they are actually filtering.

What matters more in the evening

In the evening, a phone emits 2 to 10 lux to your eyes, according to Anses. A living room ceiling light is often 50 to 200. We wear glasses for the screen, but leave the room lights on.

The steps that matter more are often simpler:

  • lower the light in the room and choose warmer tones;
  • lower the brightness of the screen, in addition to its color;
  • put it away for a while before going to sleep;
  • and during the day, get plenty of light. Wearing filtering lenses all day actually deprives your biological clock of some of the morning signals it needs.

For eyes that feel irritated after a day of screen time, the real answers lie elsewhere: breaks, distance, reflections, and an up-to-date prescription. We talk about this in how to avoid visual fatigue. And to learn everything about this blue, see our in-depth article.

Changing the light instead of filtering it

Rather than filtering the light in front of your eyes, laqi changes it at the source. Our lights follow the sun's path in your city: sunny during the day, they reproduce firelight in the evening, and dim during the 2 hours before your bedtime. No one needs to think about putting anything on.

The principle is explained in our article on light that follows the sun. To get started, there is La Boréale, magnetic light segments that also make laqi bulbs follow the sun. It arrives on Kickstarter on October 23, 2026. Get notified about the launch.

Frequently asked questions

Are these glasses effective?

Against eye fatigue, probably not, according to the 2023 Cochrane review. For sleep, results are contradictory. For retina protection, no study has measured it.

Do they help you sleep?

Clear lenses, very little. Amber lenses worn in the evening provide encouraging results for people with sleep disorders, but the evidence remains weak for everyone else.

Should you wear them all day?

Nothing justifies it. During the day, light is actually useful for your biological clock. If your eyes are tired or your vision is declining, a check-up with an ophthalmologist will be more useful.

For the record

On the boxes, eye protection is an argument that comes up often. That is precisely what the largest synthesis on the subject could not evaluate: none of the 17 trials measured it.

The most sold promise is also the least studied.

Sources