Hi all, so,

As many on this forum, I have experienced eye strain, but also headaches, pressure in the forehead, some dizziness.

And, also as many people here, my symptoms have appeared the last years but I had no problem before. As many pointed out, there seems that a technology change within screens, in the recent years, must have happened to explain those new symptoms. Now, some people also suffered before but for many others, they had no problems before those new devices came out.

I have done some research and something I found is that the backlight leds have changed since maybe 2016-2017.

Before, wled backlights in monitors were using blue leds with yellow phosphor. But they thought the yellow phosphor was lacking red color. Some years ago, they began using blue leds with red and green phosphors.

Now, one of the main red phosphor used currently, uses (cited in the source i will give a link below) massive amount of HF acid which means hydrofluoric acid, an extremely corrosive substance. I let you google this substance to see its potential hazards and its possible link to the symptoms we experience. So, scientists are aware of that, and that is the reason they are currently searching for alternative red phosphors that dont use harmful substances or in a lesser extent, as you'll be able to read from the study.

The change from yellow phosphor to red phosphor is also the reason why most of the new screens, be it on phones, laptops, or monitors, have a orangish/yellowish/pinkish/redish tint to them. They are warmer. And they have a quite intense red wavelength peak.

Especially for higher gamut monitors, as some low gamut still use the yellow phosphors.

Now, I'm not saying that is the cause of our symptoms or mine. I'm just adding a hypothesis to be discussed. What I like about it is that it is a universal change in backlight technology that has occured some years ago so that it coincidates with some people experiencing symptoms only recently. Also coincidates with many people noticing the more yellowish/pinkish screens nowadays.

Here are the studies :

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7851390/

https://opg.optica.org/ome/fulltext.cfm?uri=ome-7-9-3332&id=371019

First study mentions the use of massive amount of hf acid that restricts the further application of this red phosphor. Second study mentions some ways to reduce the higly corrosive hf acid used.

If you don't want to read the whole studies, just type acid within the page to find the mention of HF acid.

Curious to have your opinions on that subject.

    This is super interesting. I'm no scientist, so am not entirely sure how this could cause the symptoms outright, but it does further deepen the rabbit hole regarding what single thing or compound things could be happening that affect some of us.

    4 days later

    If your hypothesis is that solid state electronic components are outgassing acid, you are wrong.

    Not liking the colour of newer backlights, certainly possible.

    I am not a fan of quantum dots. I'm not a fan of overtly bright objects and it seems one of the huge selling points of QLED and QDOLED is the brightness. While I've never considered it, I can see this causing an issue for me, but I don't know that it's my main issue.

    Liberator005

    Certainly an interesting point! Most newer panels do use red phosphor but I've never given this a thought…

    Easy experiment to determine if this is a cause of strain is to try a new monitor on a Win 7 computer which @ensete uses, for example. If strain stops - it's the OS, if not then red phosphor is definitely in the discussion.

    This is interesting, recently I gave my brother my monitor because I bought a new 144hz monitor because for a recommendation I saw on another thread on here.

    Now the monitor I gave him was newer and an upgrade from what he was using to play his PS4, he was using a monitor he bought in 2017 and the monitor I gave him I bought in 2019 (just so you know he has a recent laptop and has no issues like we do) but a few days after I gave it to him, he said he feeling pressure around his eyes while using it and switched back to his older monitor and the problem went away.

    So maybe what you are talking about has some weight to it, because any monitor you buy in early 2017 most likely got manufactured in 2015 and that would be before the change in display.

    5 months later

    Great post! This post seems to align with my experience: newer screens (5-6 years old or less) that have a "warm" tint to them are intolerable for me, while older screens are fine.

    In the spirit of testing this theory, I am very much wondering if there is a way to differentiate which screens use WLEDs that are blue LEDs with yellow phosphors, and which are blue LEDs with red and green phosphors. (I once emailed several computer monitor companies asking them for specs on the WLED backlights used and they all refused to provide that information.) Most technical spec sites just list "WLED," it seems very difficult to identify the exact LED type.

    I am certainly affected by colors, so things being more red may be an issue. Although personally, in general, my LED sensitivity has gotten overall better with TV screens over the last few years, and with LED lightbulbs. Maybe the redder CCRI is good for me, who knows

    The "acid" used in manufacturing has nothing to do with the end user, though

      dev