iPhone XS What If PWM Doesn't Cause Eyestrain?

BigBen2493

macrumors regular
Original poster
May 10, 2016
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34
What do you guys think of this excerpt from the notebook check iPhone XS review: "The XS uses pulse-width modulation (PWM) to regulate brightness control, which is common for OLED displays. We measured the PWM frequency at 240 Hz, which is relatively low. Equally, the amplitude curve is so shallow that it should not cause problems for even those who are PWM sensitive."
So maybe pwm doesn’t affect people if the amplitude curve is too shallow?

https://www.notebookcheck.net/Apple-iPhone-XS-Smartphone-Review.333546.0.html#toc-display
 

BigBen2493

macrumors regular
Original poster
May 10, 2016
202
34
Further down in the article:

The frequency of 240.4 Hz is relatively low, so sensitive users will likely notice flickering and experience eyestrain at the stated brightness setting and below.

Stated brightness setting is 99%.
So why do they say about the curve then?
 

BigMcGuire

Contributor
Jan 10, 2012
4,622
5,667
California
The only time I notice flickering on my Xs MAX is when I'm reading at 0% brightness (or almost 0%) in bed at night. If I rapidly read text to the point that my eyes are flickering back and forth, I can see the screen flickering. It doesn't bother me but it is noticeable. It has been like this since day one. Upping the brightness even just a little makes this go away. I only notice this at near 0% brightness and I can tolerate it.

I am able to feel if v-sync is turned on in PC games. Without v-sync I usually get really bad motion sickness when playing games on the PC (like Call of Duty). Watching shaky camera footage gets me sick too because of the screen tearing. Movie theaters are even worse with the shaky camera - I get REALLY sick. But, barrel roll me in an airplane? No problems. Deep Sea Fishing boat? No problem. Spin around and around? No problem.

I have yet to meet someone like me. Turn off vertical sync in Call of Duty 1 and I'll get so sick in about 15 mins I puke my heart out. With V-sync turned on, I can stand it for about an hour before feeling green. I have yet to meet someone like me in the real world.

I love my Xs Max - love reading on it, I've read books on it and spent many hours watching/reading at near 0% brightness. Doesn't get me sick or give me a headache.

As C DM said ... everyone is different. Agreed.
 

now i see it

macrumors 601
Jan 2, 2002
4,013
8,015
There's verified cases where the proximity sensor (emitter) really screws some people up- and every iPhone has one & it can't be turned off.
Ad that to PWM and the Dot Projector, and it's no wonder iPhones make some people sick.
 

C DM

macrumors Sandy Bridge
Oct 17, 2011
47,484
16,005
There's verified cases where the proximity sensor (emitter) really screws some people up- and every iPhone has one & it can't be turned off.
Ad that to PWM and the Dot Projector, and it's no wonder iPhones make some people sick.
Sounds like at least parts of that if not more would apply to a lot of phones/devices.
 
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