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Old 01-15-2020, 12:40 AM   #108
DNSB
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Quote:
Originally Posted by koboyedi View Post
Wow, this discussion is drifting towards flat-earther territory, so this has to be said:

It's classical physics guys! There is not a shred of doubt PWM has an effect on people and yes (!), you don't get to have an opinion on that, since it's not up for debate. The only question is to what extent people are affected.
Could you point out where someone has said that PWM does not have an effect on some people?

What appears to being said is that the Forma uses 1KHz PWM. So far I haven't seen a study that shows any effect from PWM at that rate -- the highest rate I saw in a study was one that showed a small percentage of the participants could notice artifacts from PWM at 400Hz in saccade (rapid eye movements). One of the tests involved a single dot on the screen which seemed designed to maximize the ability to detect any effects.

Looking at quite few of the original complaints, they seemed to involve Samsung AMOLED phone screens. The majority of those early screens used PWM rates below 100Hz. For example, the Samsung A10 which uses a 77Hz PWM rate.

Not taking the PWM rate into account is similar to arguing that since I can see flicker in a 10fps video, I should be able to see flicker in a 200fps video. After all, they both have flicker.

Quote:
Originally Posted by koboyedi View Post
Next to this, most people who experience issues are not even aware their problems could be caused by something they don't visibly notice, hence the true number of affected readers is 'very likely' much higher than any forum poll could suggest.

To sum it up, there is no question if there is a problem, only how serious it is.
It's hard to find a proper double blind study. The only one I could locate that came even close indicated that while ~10% of people do notice effects from sub-100Hz PWM, that a similar percentage (~8.6%) complained about eye strain and headaches from a DC dimmed display. Google Scholar really needs to improve their search algorithms.
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