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If you suffer from PWM eye strain from OLEDs, I thought lower frequency is better?  Like 119hz is better than 300hz. But i keep seeing articles saying super high frequencies are better on your eyes?

 

Based on notebookcheck, they always say the measured PWM is not as bad at higher brightness levels. And the higher brightness levels show a lower HZ frequency in the test results, NOT higher. See screen shots attached.

 

"This OLED panel uses PWM, but this is hardly measurable in the brightness range between 95 and 100%.".

 
 

.....So using notebookchecks results I was trying to follow the calculations below. But don't know how to get modulation percentage:

 

 

In closing, what are the workarounds to determine if it is truly pwm-free?

Two options to be not affected by the invisible flicker:

Option A: Ensure that modulation % is at least lower than (0.0004 of the PWM hertz)

Option B: Ensure that PWM hertz is at least higher than 2500 times of the modulation depth %.

Question ~ if I am only PWM sensitive and not light sensitive?

If you have a history of being able to use oled from 2018 galaxy S9 era, then use the below calcuation formula instead:

0.016 * PWM hertz.

Thus ensure your modulation depth % is below than (0.016 of the PWM hertz). This is PWM-safe for you.

Screenshot_20250112_171504_Firefox Beta.jpg

 

Screenshot_20250112_171507_Firefox Beta.jpg

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The higher frequency is better, there are phones that have it in thousands.

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Higher frequencies are better as they are inherently less noticeable - lower frequencies means each on/off cycle lasts for a longer time. The shorter the cycle, the less noticeable; if you flash a light on and off faster and faster, at a given point it will start looking like it's turned on all the time, and at some point beyond that it will also stop looking like it's flickering.

Also, a misunderstanding in your OP here: PWM frequency does not vary across brightness ranges - that's not how PWM works, generally speaking. PWM is Pulse Width Modulation, which broadly speaking works like this: brightness is varied by varying (modulating) the "width" (length of time) the pixels are given a signal (pulse) to turn on, within a fixed rate of pulses per second. As an example, for the sake of simplicity let's use a PWM frequency of 100Hz: each pulse could be anywhere from 0 to 1/100th of a second, before the next pulse cycle starts. Within each 100th-of-a-second pulse, the pixels can be told to turn on for however long is necessary to reach the desired brightness, with a 100th of a second pulse width equalling the pixel being on all the time, in other words achieving full brightness.

Now, it's possible to also vary the pulse rate across a PWM range, but this requires a more advanced display driver circuit and far more advanced firmware, as suddenly you have to deal with translating PWM signals acrooss multiple different rates to achieve linear changes in brightness.

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7 hours ago, Valantar said:

Higher frequencies are better as they are inherently less noticeable - lower frequencies means each on/off cycle lasts for a longer time. The shorter the cycle, the less noticeable; if you flash a light on and off faster and faster, at a given point it will start looking like it's turned on all the time, and at some point beyond that it will also stop looking like it's flickering.

Also, a misunderstanding in your OP here: PWM frequency does not vary across brightness ranges - that's not how PWM works, generally speaking. PWM is Pulse Width Modulation, which broadly speaking works like this: brightness is varied by varying (modulating) the "width" (length of time) the pixels are given a signal (pulse) to turn on, within a fixed rate of pulses per second. As an example, for the sake of simplicity let's use a PWM frequency of 100Hz: each pulse could be anywhere from 0 to 1/100th of a second, before the next pulse cycle starts. Within each 100th-of-a-second pulse, the pixels can be told to turn on for however long is necessary to reach the desired brightness, with a 100th of a second pulse width equalling the pixel being on all the time, in other words achieving full brightness.

Now, it's possible to also vary the pulse rate across a PWM range, but this requires a more advanced display driver circuit and far more advanced firmware, as suddenly you have to deal with translating PWM signals acrooss multiple different rates to achieve linear changes in brightness.

 

So I'm confused because every review that notebook check does, they say the PWM is less (there's is less PWM) at higher brightnesses. And some have no PWM at all above 90% brightness or 80%.THey emphasize the PWM being worse at lower brightness levels.

 

And those lower brightness levels have higher Frequencies.

 

See attached screenshot from this review:

 

https://www.notebookcheck.net/Lenovo-Yoga-Slim-7x-14-G9-review-Multimedia-laptop-with-Snapdragon-X-Elite-and-great-3K-OLED-display.875964.0.html

 

 

The screenshots attached are from OLED screen laptop reviews. One was a yoga the other was an HP. But you'll find it on any one of their OLED laptop reviews.

 

Screenshot_20250113_133840_Firefox Beta.jpg

Screenshot_20250113_134306_Firefox Beta.jpg

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