hayder1983 how do you measure PWM?
Does eye strain depend on the display's refresh rate?
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Zodios Well with a flickermeter. This one below is a cheap one, but it tells you the frequency of the PWM used and brightness in lux/nits. For example my laptop uses 240hz PWM on highest brightness setting and goes down to 100hz on lowest brightness setting. It is cheap and maybe needs light to be a minimum brightness to actually correctly measure anything, but it is good enough for screens and lightbulbs measuring "white". Follow the link for some example measurements: https://ledstrain.org/d/1176-flicker-free-led-lightning-its-the-most-important-thing-which-one-to-buy/45
Frequenz= PWM frequency
I should add the fact, that i like my white on screen to be 10-20 nits. 20 nits is actually very bright for my eyes, at least on a screen that i use for 8 hours. I think a lot of screens are doing a bad job on minimum brightness setting to make a non flickering light. 10 nits is really more of a light grey, but i forget about it after a few minutes of work and the strain is much less.
For some reason the new monitors i tested are always straining me, even on 10 nits, my old 2009 TN-Panel didnt, but it became unusable, because every adapter introduced nausea on my old screen. Perhaps it is not even the adapter, but a driver issue?!
But i am pretty sure there is some "pounding" on the back of my eyes with some displays and all of them have a very high frequency. There is no pounding on my phone/TV/tablet/steam deck. There is strain, but not in the back of my eye.
7 months later
1NGIBITOR FWIW most cars built in the past 10 years use PWM for the dashboard (speedometer, etc.), not to mention the infotainment center.
4 days later
ensete me too.
Personally, I find that a high frequency (90 Hz on my phone) causes faster eye fatigue than 60. Same with screen resolution, the smaller it is and the less detail I see the better it is for my eyes. The same applies to the number of colors/shades
6 days later
Very interesting finding, also. I was using my old good setup connected to external monitor to do editing and, after a day's work, I felt my eyes very tired, which was weird. The OS is 8.1, so no software changes to blame. Only days later I found the refresh to be set to 60 instead of default 59. Changed it, as it was the only setting altered, as I knew them all by memory, and the things improved in a considerable measure. The monitor is 8 bit and does not have PWM. Very weird for me, but it's a fact.
a month later
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Alyosha2001 Yeah, I have noticed that, too. I noticed that settings from Ultra HD, HD section much softer on the eyes than from PC in terms of windows. To be more precise, the screen refresh rate and the time allocated for drawing lines and frames on the monitor are unsynchronized. This causes some flickering of the picture (not backlight).
If you play with this settings (https://www.nvidia.com/content/Control-Panel-Help/vLatest/en-us/mergedProjects/nvdsp/To_change_the_timing_formula_for_your_HDTV.htm) then you will notice some changes (improvement or worsening of the pressure on the eyes), which proves the influence of this parameter.
23 days later
In my experience, no. If you have 2 display that are both matte, LCD, PWM-free, no temporal dithering, etc., refresh rate does not have any impact on eye-strain.
I beg to differ, higher refresh rate may mean higher frequency flicker caused by pixel inversion - the higher the frequency the higher the comfort. Theoretically.
Of course the question is if manufacturers increase the pixel inversion polarity switching frequency with increasing refresh rate. I am usually getting better results with higher refresh rate. But not in every case.