Deepdeep That is exactly what I'm trying to say. There is a different spectral distribution. The backlight with higher intensity generates a harmful emission that the LCD layer couldn't block at all though you put the brigthness to 0%. I confirmed this situation because I tryied it, it also hurts my skin but in less intensity. The backlights with lower nits doesn't generate a harmful emission. In old LED TVs (not PWM) lowering the backlight intensity (not the brightness), causes the disappearance of symptoms. I'm an electronic engineer and know about it. When you apply a higher current to a LED or CCFL light you generate a kind of light that get closer to the frequency of UV light that is more harmful. Warm light is better (3000 Kelvin) than cold (6500 Kelvin or higher).
Screens with very low maximum brightness levels
RobC In my post when I'm talking about brightness I refer to the settings of the LCD layer that blocks the light that comes from the backlight, not the real backlight intensity that in some displays has his own settings to regulate it. These separated settings are true in older displays with DC dimming, (not PWM). In newer displays with PWM the brightness is regulated by the percetage of the cycle in which the backlight is on at 100% of intensity. In this case Oled saver kind of apps are equivalent to set the brightness of the LCD layer to a lower value, but not to lowering the intensity of the backlight that is the real problem. That is why it is not enough for everyone.
RobC Hurting your skin is not a normal reaction and you need to consider that some of this might be psychological because logically, you should hurt every time from every light source including the sun since they all put out way more power than a little backlight. If everything is fine except for the backlights of monitors, then you have some of your answer.
And no, you don't get ultraviolet light by turning up the brightness on phosphors that are specced to emit at specific nm frequencies in the visible light range. That would be pretty wild if so much current was flowing that it shifted to ultraviolet. I can't see that passing energy star.
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Sunspark The hurting of the skin might be psychological based on the belief that the light is actually "harmful" but it might also be part of a nervous-system response to something about the screen eg pwm, dithering, etc. I get various and varying reactions including itching and aggravation of the psoriasis on my scalp (which happens almost immediately), "sticky-eyes", brain-fog etc none of which happens on a "good" device.
I don't think that the intensity of the light from displays causes any direct harm/damage, at least at average brightness levels, but I wonder if there is something about the light itself (other than stuff like pwm, dithering etc) from some backlights that some people are reactive to, like maybe differing spectral distributions, which might be the cause of my reactions to some devices with no pwm. I haven't looked into dithering yet because only one of my problematic devices is a Windows one and I don't know that there is any fix for dithering on Android or IOS.
Sunspark Everything is fine except for the backlights of certain displays, that are always the same, and never others. Psychological reason is the typical answer to others when you don't know enough of something. It only hurts the part of the skin that is exposed, and the more time exposed or the more the intensity of the exposition, higher is the sensation. I know it is not common but is the same answer that all of this forum receives from others when we talk about our eyestrain. Something is bad about these backlights an I'm sensitive enough to detect it through skin too, not only through eyes.
Sunspark This link explains why people react different to the light due to a difference in the internal filter of their eyes that block harmful light. The same situation is with the skin.
Sunspark I adjusted it but it not solved the problem. What I was trying to show with this articule is the intrapersonal variability of the discomfort threshold. That 's why we are here, because we are affected by some displays and other part of the population not. In our case, some backlights are worse and activate our discomfort surpassing our threshold instead of others that not.
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I haven't read the whole article but the pics with the differences in the spectral readings of various devices are interesting. Do you think the light is causing damage to your skin or just pain?
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Deepdeep Yes, I think so. At least it gets dry after short time like if I were at the beach, and with my eyes too. I had an excellent night vision and now, after exposing to harmul displays, I have a foggy vision at dark in the night. Specially just after the exposition.
Here you have another interesting link:
https://glarminy.com/2016/05/06/blue-filter-light-sensitivity/
Hi - I’m thrilled to find this discussion thread! Your described symptoms in response to screen time are nearly identical to what I’ve been experiencing since starting my job as a technical writer several years ago (and being given a new Lenovo work laptop - along with 1-2 additional monitors). In particular, I noticed shortly after getting this PC system that I became very fatigued at the end of the day, feeling as though I couldn’t stand another 10 min of screen time. Over the next few weeks, I noticed that my face felt exceptionally dry after 3-6+ hours of screen time, I also had significant skin pain, as though I was being burned (or sunburned), after every workday. I even noticed a characteristic lines along the nasolabial folds of my face after a day of work - these would go away after a weekend away from the work screens, but we’re back after getting back to work the following week.
This has been going on for 2+ years now, and I feel my skin is increasingly damaged. I’ve lost a lot of what I suspect is collagen in my cheek areas, and have developed true wrinkles along my laugh lines (nasolabial folds) - note my skin was wrinkle free. My skin is perpetually red and feels dry and burned all the time. My lips feel burned too.
Importantly, as per RobC’s comments, I’ve never noticed screen time issues with my main non-work computer, an older ASUS ROG laptop (~10 yrs old). In fact, I still use this PC with no issues (I’m currently looking into figuring out what type of backlight system it has, maybe CCFL or just an older LED).
Another parallel with RobC is that within a year of using these new screens, I lost my night vision. As he described, my vision at night is just terrible now, things are fuzzy, and sometimes I literally put my hands out in front of me so that I don’t fall. Prior to getting this system I had excellent night vision (would drive all my friends around).
Obviously, I’m really upset about all of the above, but unfortunately am in a situation where I need to continue with my current job.
My question here is that did you (RobC), find any kind of resolution? Has using screens with older backlighting technology helped? Or have you found any other solution? I’m also considering trying a projector, but I think finding a screen that didn’t nuke my face every day would be easier…
Thanks in advance, love this forum!
hi @Nyyount , it is a good news to find someone with similar symptoms. In general CCFL monitors are much better than LED ones, but there are some cases I´ve found that are also harmful for me. I think that the rules is that we have to avoid LED flicker screens (PWM) and the maximum amount of nits needs to be much lower than the lasts displays offers now. At home I need to use CCFL monitors for work, and an old mobile phone. Most of the displays got worse since 2017, but there were some bad displays from 10 years ago too, The general rule found is, the more attractive the screen the worse it feels
at least sunscreen should solve your skin problems if it's caused by light