[Feature Request] PWM display options to reduce screen flickering

Elephant

https://github.com/GrapheneOS/os-issue-tracker/issues/3850

Came across this ticket on the GrapheneOS issue tracker. Extremely disappointed by the response. It is ok to stare at a screen with aggressive flickering even when it triggers a physical manifestation of medical symptoms? And it can not be solved by any current medical treatment!

The display industry is rather secretive. As far as I am aware no one from Samsung or other company has joined in to either justify the decision or work towards a solution.

Elephant

For me it's like erasing flash memory with zeros for privacy - it would also affect the chip's lifespan and failure rate, and I believe it's up to the user to accept the risk, if any.

I do not think using flawed analogies is productive towards this cause either. Wear leveling going to get ya ;-)

x11rl

@Sindbad while the following won't help regarding GrapheneOS or Pixel devices, this is exactly what Daylight is doing with their flicker-free and no-blue light DC-1 tablet. Keep in mind, this is a health-oriented device designed for such people, but Daylight is taking on a hugely important topic and doing some seriously cool stuff with their display technology.

Seth for Privacy (GrapheneOS advocate) reviewed his unit here:
https://sethforprivacy.com/posts/daylight-dc1-magical-imperfection/

If anyone wants to nerd out further on this stuff, Dr. Jack Kruse is generally regarded as the go-to source for all things circadian biology and how it pertains to the technology we use.

headphonejack

I also would greatly appreciate improved PWM if in any way it was a simple addition to the (already heavily modified custom) grapheneos kernel.

pwmsensitive

Sindbad Applying the method right now requires root and a custom kernel, but this would not be the case anymore if GrapheneOS would be able to integrate the function as a native software feature.

A developer I'm in contact via XDA is working on getting the PWM mod he made for his own GOS build into the main GOS. But I don't know if he will be successful.

"The PWM modded GrapheneOS kernel is working." https://xdaforums.com/t/a-mod-on-pwm-frequency-v3-20241027.4683727/post-89808904

pwmsensitive

The kernel changes (as used in the proof-of-concept) are published here: https://github.com/elephant-43/kernel_devices_google_shusky

Elephant

pwmsensitive See also: the display module repository. These do not function in isolation as they just expose certain display parameters in sysfs.

Certainly I believe a solution for integration into GrapheneOS requires additional work.

pwmsensitive

Elephant integration into GrapheneOS requires additional work

An integration would be a dream come true for me (pwm sensitive)! :-)

Elephant

pwmsensitive An integration would be a dream come true for me (pwm sensitive)! :-)

This is probably a question better asked in one of the Matrix channels, but is there any documentation/references on integrating privileged functionality into GrapheneOS sans root access? More specifically it is to write to a sysfs device file. Or is there are more preferred means of kernel/userspace interaction than sysfs primitives?

Upstate1618 Why does it matters? I can't tell any differences between different frequencies. Is it because I'm not sensitive to pwm frequencies or I've not met the specific scenario?

Sensitivity to flickering light and the associated effect with displays is a known phenomena. So if you are unaffected consider yourself lucky and continue using GrapheneOS as normal. :-)

Upstate1618

Why does it matters? I can't tell any differences between different frequencies. Is it because I'm not sensitive to pwm frequencies or I've not met the specific scenario?

quantuser

It seems that Apple introduced a toggle to turn off PWM completely for the iPhone 17
https://www.macrumors.com/2025/09/09/iphone-17-pro-pwm-toggle/

Maybe Google will develop something similar for the Pixels?!

de0u

quantuser Maybe Google will develop something similar for the Pixels?!

Maybe somebody could get a 9to5google or Android Authority reporter to ask Google?

Ilgar

quantuser
Now I am jealous!

edit: false alarm

from comments to article:

Results on the subreddit ‘Pwm Sensitive’ aren’t not promising.

for a short time today under 30% only with the toggle on, I will say it IS an improvement, but it's nowhere near enough for me sadly, and to only work under 30% brightness.

quantuser

Ilgar
Ok, it seems this is not the best solution, but at least the topic gets some attention. Google implementing a 240 -> 480 dimming switch and Apple also doing some changes for <30% brightness. So maybe there is hope for more and better solutions.

Novalissoide

Ilgar dammit Ilgar, I haven't noticed the pwm until now... Now I see it all the time.

Ilgar

quantuser yeah, and the name of technology is microled, or at least miniled :)

TrustExecutor

How is the Pixel 10? Anyone tried it?

Ilgar

Novalissoide

the most funny thing of that laboratory rat technology is dithering. pwm is flickering of leds, while dithering to mimic 10–bit is 8–bit + FRC that is flickering colorful leds, so effectively colorful stroboscope. on top of that, people don't use night light mode, so bluelight is the other attack. 4 years with gos devices, 4 years of suffering

the only things one can do its to enable:
dark mode, night light, extra dim, grayscale color correction

Novalissoide

Ilgar now that is some deep stunting. I'll try it tonight.

Ilgar

Novalissoide all 4 toggles are available in control center.

disable auto brightness and make it 100%, set extra dim to dimmer. extra dim adds gray transparent layer to interface, instead of lowering brightness with pwmodulation

night light amber screen makes it easy on eyes, but don't forget to disable it to edit photo/video

with dark mode you don't have all screen flashing in your eyes but only characters and some interface

and grayscale... if you get used to it like I did, it's a balm! most important thing of this oled tunning, in my opinion

Novalissoide

Ilgar a huge thank you for this tweak.

Canardo_Sanchez

Ilgar I measured the P8P with an Opple light measure device and found no obvious gain with dark filter, even pushed to the extremes.. It just produces weird ass curves that looks no less agressive than without it.

But it's just a graph off course, if your eyes likes it, then use it. Personally only night mode saves the day (badabum tsss).

tarbeez

Ilgar what do you when you e.g. use the phone in a dark place? Reduce the brightness and keep everything else? Does reducing the brightness nullify the effect?