From another comment summarizing contents it seems this research focuses on danger of permanent damage. Just because there isn't permanent damage from blue screen light doesn't mean that it can't also be more comfortable to you and promote healthy sleep to filter it out

I wonder if it's a way to decrease brightness while maintaining better visibility.

Not really what you were asking but I thought I'd throw it out there anyway.

On an iPhone, Settings > Accessibility > Display & Text Size > Color Filter > Select Color Tint > Select Deep Red > Intensity 100% & Hue 100%.

Go back to Accessibility and select Accessibility Shortcut > Select Color Filters.

When I'm reading in bed, I triple press the right button and it turns my red filter on. I've noticed a significant decrease in eye strain and I find it doesn't keep me up at night.

I know that is counter to this post, but it works for me so might be worth a try.

Great tip.

I’ve just done this and it’s perfect for nighttime HN reading!

The human eye has quite a lot of chromatic aberration, and if you basically get rid of the blue it makes it a lot easier to focus on distant things.

My vision is perfectly corrected for infinity when I have my glasses on under normal conditions, but at night when my pupils are wide open, I simply cannot focus to infinity at blue wavelengths.

I used to get frequent headaches and eye strain during work. I bought blue light filtering glasses, and the problem went away instantly and hasn't come back. Placebo or not?

Same experience here, has made a world of difference

Depending on how a statistical experiment was designed, I could imagine a variety of results though

Same here but maybe it's simply a case the filtering out blue reduces the total light intensity enough to be easier on the eyes. Wonder if similar results could be accomplished by filtering red instead or simply turning down the brightness on our devices and using lower lumen bulbs around the house.

Blue light carries the most energy, so I imagine filtering it out has the greatest effect compared to those other mitigations.

What do you mean by the most energy ?

Blue light has more energy per photon (energy is proportional to frequency). Therefore, it is better at ejecting photons from atoms and damaging molecules than other visible light. UV is even worse.

Also, semi-related, eyes are less sensitive to blue light, so if you want to achieve the same effective perceptual brightness, you need more photons if it's a higher color temperature.

Kind of nitpicking, red light energy is around 2eV, while for blue light around 2.5eV, it's not like it's a very sensitive difference.

UV is much higher energy, in the range of 40 eV~.

I also sleep better on days when I wear my glasses (which have a blue blocking coating) as compared to my contacts. Unfortunately the contacts provide better vision, thanks to my astigmatism.

How does astigmatism help to get clearer vision?

It doesn't. But my contacts correct for my astigmatism much better than my glasses do (which may or may not have any astigmatism correction, I'm not sure). So the vision I get out of my contacts is sharper than my glasses, but my glasses offer blue blocking. Tradeoffs.

I guess most of this is because it makes your screen darker, not because it's specifically filtering blue. Most displays are set up way too bright.

Doesn't mean it's dangerous like the ads say