TM-39-25 is a document from the Illuminating Engineering Society that puts forth a classification system that seeks to reduce human responses to flicker. I often call the classification system itself "TM-39-25".

The system utilizes three different flicker effect visibility metrics, Mp, SVM, and PAVM. These metrics are scores computed from the flicker waveform that seek to predict the likelihood of a "temporal light artifact". I go over each metric in detail in the video, but here's a summary table:

https://preview.redd.it/wcv2st4dl8kh1.png?width=2720&format=png&auto=webp&s=959251de6d086b0e7e14ac6f2db3e2f29c9538ed

Simply put, a temporal light artifact is a visual disturbance of some kind due to flicker. TM-39-25 classifies light sources based on all three metrics simultaneously. I see this classification system as a vastly improved (but not perfect) replacement for IEEE-1789 classification, which are the frequently posted here as part of the results the Opple Light Master produces. Here's how the metrics scores map to the classifications:

https://preview.redd.it/eu77sdtkl8kh1.png?width=1505&format=png&auto=webp&s=bdaab419feb5c6a00f6c45dcbbc1bf5b39487d0b

I think this standard can be used as a replacement for the IEEE-1789 classification. The three metrics or "scores" it uses provide much more useful information and were created based on the results of experimental studies.

I have built this system into the flicker meter I'm working on (TLM-110), and used it to measure a variety of bulbs:

https://preview.redd.it/k6h1yilfk8kh1.png?width=2300&format=png&auto=webp&s=4bc5c3624bc7fd71a4c7f82ab347d5ebf3180e51

You can see there's a wide range of classifications in the bulbs I tested, as well as a large spread in the scores. The bulbs that are "Not Recommended" are unbearable to me, while the bulbs that are "Better" are much more tolerable.

I think this system has the ability to be broadly useful, especially for non-experts. However it isn't perfect. Firstly, while it technically applies to all light sources (displays included), it is most relevant to lighting such as bulbs and lamps. There are likely screen-specific flicker effects that haven't been described yet. Also, it mainly predicts the visibility of flicker artifacts, which are visual disturbances, not health effects. I think flicker artifacts and visual disturbances may be correlated, but there is not a one-to-on relationship.

Thanks to u/Rx7Jordan for making me aware of this standard.

Recently i started experiencing eyestrain from my phone (it's a PLS LCD with no pwm) and noticed that the brightness doesn't go all the way down despite having it on 0% so I had to initially install the screen dimmer app, which helped my eyestrain, however i'm trying to figure out why brightness bothers me and what may have suddenly changed in my eyes (presciption changes, weak eye muscles due to anemia? which i have right now) probably, why i feel like suffocating when staring at the screen? Because my eyes are so weak right now that its a marathon for them to start at screens? Also the fact that i'm frequently experiencing photophobia.

Maybe it's changes in the screen itself causing sudden eyestrain from apps that never gave me an issue.

I did notice Instagram updated their UI and even Youtube, both of which are giving me issues even on web versions.

I did ask on LEDstrain.org but got gaslit by this one person named ensate when I mentioned how genetic astigmatism or autoimmune conditions can contribute to eyestrain, and that i cannot afford e ink screens. This pwrson told me i was making excuses and that I'm wrong.

I'm stuck on a G34 5G with 4GB of RAM and it's driving me crazy because it has a terrible battery and zero multitasking capabilities...Do you have any smartphone recommendations? I've already tried loads, and dithering bothers me as much as PWM...I hate my life...I recently tested a TCL 70 Pro, it was awful...

I have been waiting for the release of Pixel 11 pro XL. Currently using Oppo find X8 for the fantastic pwm frequency but really missing my older devices like Samsung ultra,Pixel,Iphones .

Please help about the PWM frequency of Pixel 11 pro XL. Anybody has any update on this? Also help me decide if it is 240hz on pixel then how about Iphone 17 pro max. Really need the help on this topic.

Many of you have noticed that r/PWM_Sensitive has gone through some growing pains when it comes to how posts and comments are moderated. While the subreddit was never unmoderated, it became clear that some additional help was needed due to personal circumstances, and that a fresh approach to moderation would benefit the community.

We are happy to share that u/the_top_g, the creator of r/PWM_Sensitive, has graciously stepped aside to welcome in three enthusiast community contributors to help with moderation and the future direction of the subreddit. We sincerely appreciate the trust he has placed in us and, most importantly, his work in creating this community in the first place.

The interim moderation team is currently discussing ways to improve the subreddit while preserving what has made it such a useful resource for people who are sensitive to PWM, display flicker, and related technologies. Our goal is to keep this an open, welcoming, and informative community where people can share their experiences, testing, research, questions, and device recommendations without unnecessary barriers.

AutoModerator Changes

Perhaps the most noticeable (and controversial) issue has already been addressed: the previous AutoModerator configuration is gone.

This means comments should no longer be automatically removed simply for using common words or phrases that naturally come up when discussing PWM and related topics. This includes “temporal dithering.” Members banned over this issue are also being reinstated.

That said, we ask everyone to continue keeping discussions primarily focused on PWM sensitivity, display technology, eye comfort, device experiences, testing, and closely related subjects. Normal subreddit rules and Reddit-wide policies will, of course, continue to apply.

The Future

This is only the beginning. We're reviewing the subreddit's rules, moderation practices, organization, place within the wider community, and other areas where we believe improvements can be made. As those changes are decided upon, we'll communicate them with the community.

We also want r/PWM_Sensitive to be shaped by the people who actually use it. Constructive feedback and suggestions are welcome. If there are things you think could make the subreddit more useful, organized, or welcoming, please let us know.

Finally, thank you again to u/the_top_g for creating r/PWM_Sensitive and building the foundation for this community. And thank you to everyone who has contributed over the years -- whether by sharing measurements and research, documenting your experiences with different devices, answering questions, or simply participating in the discussion.

We're looking forward to the next chapter of r/PWM_Sensitive and making this community an even better resource for everyone.

p.s. Check out the new (temporary) subreddit logo! 😁

Edit: for tweaks suggested by u/Z3R0gravitas.

Honestly I don’t do doomscrolling..i have a lot to study in my laptop i m a tech guy so how can i protect my eyes from that?i can feel the strain of my eyes??

I purchased a 43” Sony Bravia 3ii bc of the lack of flicker. However, I also need a TV that gets dark bc I want to watch in my bedroom, and my eyes are sensitive to light. The Bravia 3ii gets somewhat dark if I crank brightness, contrast, etc down to zero. The image crushes, but at least it’s dark. My problem is arising with the menu/interface. When I go to the menu to select a streaming platform, the platform to select a show, or even just to fast forward, it’s blindingly bright. Anyone have any suggestions on how to fix it or what tv to trade it for?

I had also considered the LG B5 OLED bc the lights actually individually turn off for black/darkness, but I’m concerned about flicker even though it’s a different kind. And the Vizio Mini LED Quantum 4 bc I used to have an old not-smart Vizio that I tolerated and got really dark. Anyone have experience with these?

Hi. Did anyone try the global/eu version of Reno16 Pro vs Oppo find x9 (normal, not pro)?

I have a OnePlus 15R which is amazing, but a bit too heavy and big. I tried honor 400, even with ADB commands, but it is harsh on my eyes still. I would prefer Reno due to size, but I only find info about find x9.

Please provide feedback on the two models on pwm and D and how you felt. Or some other small phone that could work.

Thank you!

I've been looking for a decent phone that I can replace my current iPhone 16 with, since I can only tolerate it for a few minutes a day. I've been looking at a lot of OLED test reports, and I think I've noticed a problem with many of them: the measured flicker is falsely low, since the photodiode is measuring multiple OLED rows at once. In my opinion this results in a loss of information about what the screen is really doing.

In some extreme cases, I've seen devices which actually have 100% modulation depth be measured at ~5% modulation depth. All the OLEDs I've measured with this method (using my meter or the Opple) actually show 100% modulation depth at all brightness settings. I'm not confident this is true for EVERY device, but I think there are a lot of measurements online that underestimate the OLED flicker.

I showed this in the video, but to avoid this error you simply have to reduce the number of OLED scanning rows that the flicker meter detector is exposed to. Ideally, we'd only measure one row since this contains all the relevant information. In practice multiple rows are needed to get enough light onto the detector.

For me, it might be time to just buy an e-ink phone.

Tl;dr - lots of different phones are causing me eye strain, but I'm not sure what the problem is. I think it isn't PWM but I just don't know.

Up until about eight months ago, I was using a Samsung Galaxy S9 Plus. I'd never had any problems with it in terms of my eyes, but it was dying, so I needed to replace it.

Important context: I have a chronic illness that makes me very sensitive to light, so my screen is always extremely dark. Again though, never had any problems with my Samsung.

I'm putting a list here of phones I've tried, information that I think is relevant, and the results in terms of usability for me:

Samsung Galaxy S9+. PWM 215.5 Hz. Given that this didn't cause me any problems, I decided that I probably didn't have any PWM sensitivity.

Nothing CMF Phone 2. PWM 90 Hz - eye strain after a few minutes. As the PWM is very low on this phone, I then decided that so long as I got something equal to or higher than my original Samsung, I would be fine.

Motorola G75 5G. LCD gave me headaches/migraines, and I just wasn't able to turn the brightness down to a comfortable level.

Pixel 9 Pro: PWM 240 hz (still low, but higher than my old Samsung) Eye strain after a few minutes. I've since learned that Pixels are a bad choice for eye strain, but I did not look this up in advance because I'm an idiot.

Honor 400 Lite: PWM 3840Hz. Other features that are apparently good for the eyes. No eye problems. But I rely on a couple of different accessibility features and those are not super reliable on this model. I reckon a higher-end Honor phone would also probably be fine, because the 400 lite is one of their cheaper ones.

For reasons of personal preference, I would rather not get another Honor. That said, if that's the only brand that will be gentle enough on my eyes, I'll go with it. But I don't even really understand the issue I'm having to be able to get a phone that would prevent it. Does it even sound like a PWM problem? If it's not that, what other things could I look for that would be more gentle on my eyes?

I'm feeling very frustrated and confused, and any advice would be much appreciated!

I am looking to get a new car, and it seems like every car made in the past ten years includes a bright infotainment display screen in the middle of the dashboard (for calls, navigation, music, etc). I can turn down the brightness to the lowest level, but this only helps my eye pain to a degree.

Has anyone found any solutions for this? Only some of the screens even turn off completely, but then you lose most functionalities. Thank you!!