• AbstractPWM

  • Eyestrain From Screen Refresh Flickering On Moto G54

George357
I bought new OnePlus Nord CE 3 Lite in 9th January for 158 euros & I flashed LineageOS 2 hours after buy. It just got official LineageOS status in 4th January.
It works very well without any noticeable bugs in my usage, I like it (even VoLTE works).

It's flicker-free when I compare it with Poco X3 NFC, which had some flicker below 65% brightness. Nord didn't have any across all brightness range. But note that I didn't use some more professional tool to compare it, just a camera with 1/4000 shutter speed.

For me, I don't have eye-strain with it compared to Poco, but experience may vary.
It's the only new PWM-free phone I know which has custom ROM support.

      fiftydinar Thanks for sharing that. I've looked an Nord CE 3 Lite in the past but always decided against because there didn't seem to be any good stable custom ROM for it and the stock ROM seemed poor. With official LineageOS it's a more appealing prospect. Having exhausted almost all the other phones on my list of Potentially Usable Phones, I think I'll buy one and see how I get on with it.

        moonpie Thanks, I've read it. According to their review, no PWM but as we have found from the G54 and G34, that doesn't guarantee there is no flickering. The best we can do is to take the Notebookcheck review as a starting point for Potentially Usable Phones but to really know if a phone is flicker-free, you just have to buy one and test it yourself. But when even PWM-free phones have flickering we are entering difficult times. Will there ever be any more truly flicker-free phones?

          moonpie non-LTPO

          Agreed. I also think, LTPS (a-Si) much better than LTPO / oxide TFT

            • qb74

              • Post #39
              • Edited

              George357
              This is an excellent observation you've noted.
              Every transition on your display may exhibit flicker / brightness oscillations.
              This could very likely be a much larger culprit to eyestrain complaints than the software dithering talks on these forums.
              Adding VRR (variable refresh rate panels) on top makes this even worse.

              For example, desktop OLED displays have a 25% brightness drop every refresh cycle (if 240hz display => every 4,17ms)
              If you were to use it at 250cd/m2, it would drop by 80cd/m2 every 4,17ms (not a full on-off cycle, but on-semi off)

              This is sadly an issue that very likely plagues a 99% of smartphone display models and even some desktop displays.
              This can only be troubleshooted with proper G2G response times testing setup, using an oscilloscope and a good probe, the OSRTT or similar devices.

                7 days later

                So following the tip from fiftydinar I bought a Oneplus Nord CE 3 Lite 5G and... Hallelujah! It's flicker-free! At all brightness levels. I've been using it a for a week now with no ill effects, no eye pain, no discomfort at all. Examination with my flicker detector shows no flickering apart from some very low amplitude oscillations associated with the screen refresh. The trace looks very similar to that of my Redmi Note 8 shown above which is reflected in my experience - no problems. I haven't found any complaints from others about eye problems with this phone so I think it is a safe choice for those of us who are sensitive to flickering. The Nord CE 3 Lite 5G is called the Nord N30 5G in North America and I believe the Realme 10 Pro is the same phone.

                  George357

                  I'm very glad to hear that!

                  Realme 10 Pro is basically the same phone as you noted, but older. There are slight differences in design, slower charging & slightly brighter screen. I thought about buying it, but there are no selling offers for it in my country. I prefer the Pastel Lime color of OnePlus anyway, so I don't regret it.

                  I think that we should hold tight on this phone, because it's the question if we'll have any good choice like this in the future.
                  The phone we bought is 1 year & 9 months old & phones which got released after that period of time are sadly not flicker-free. Nord CE 4 Lite as a successor has Amoled & I hardly see this trend stopping.
                  But let's hope that I'm not correct on this & that some good similar flicker-free phone will deny my predictions.

                      George357 You're lucky, I tried the Nord N30 last year after only 20 minutes of using it felt extremely tired / dizzy / brain fog. It was flicker free PWM-wise, but something else about it was messing with me. The UI seemed really blurry even when UI scaling was set to the "native" amount, it felt like everything, especially icons and lines had an unnatural shadow or blurry glow around it in addition to white backgrounds seeming too harsh. The viewing angles also seemed unnatural, like when looking at it flat on a table it seemed to have a metallic effect as I moved around that I don't usually notice on phones. After those same symptoms happened 3 times using it I had to return it.

                      It was on Android 13 BTW, so these problems were not related to Android 14.

                      Also, I don't like that on the N30 and many other OnePlus/OPPO phones the variable refresh rate cannot be locked to 120, I notice it whenever the refresh rate changes, and trying to lock it to 60 felt more uncomfortable to me than 120 did.

                      Possibly, there is a panel lottery for this phone, maybe you ended up with a better panel than I did (or there are potentially more differences between the CE 3 and N30 beyond just the name)

                        8 days later

                        fiftydinar It seems I may have spoken too soon. After installing crDroid on my phone it has been giving me some eye pain and it's becoming a problem. I am not sure why but I think it has something to do with the screen refresh flickering which did not seem to be a problem with the stock ROM. On the oscilloscope this flickering is at 120hz regardless of the refresh rate applied in the settings. I always ran the stock ROM at 60hz but selecting that in the crDroid settings has no effect on the flickering frequency. On the stock ROM there were just three options: 60hz, 120hz and Auto, but in crDroid I have two settings, one for peak refresh rate and one for min refresh rate with options between 30hz and 120hz so I am wondering if the implementation is different in crDroid. I thought of installing LineageOS to see if it is more like the stock ROM in this respect but maybe you can save me some time and tell me what the refresh rate options are on your LOS installation. Thanks for your help.

                            George357 it has been giving me some eye pain

                            And specific difference in screen measurments ( extra pulsations, more intensive pulsations ) ?

                            New OS could have dithering, or activate FRC in phone screen

                                simplex I'm still investigating this unexpected setback. I'll write up a detailed report when I've done a bit more research.

                                  15 days later

                                  simplex Whatever my problem was it is resolved. I am confident it was not down to any flickering, I re-examined the phone with my flicker detector and found nothing. I stand by my original conclusion that the Nord CE 3 Lite 5G is flicker-free, at least the one I own is. I am not sure what was causing the eyestrain I was getting, maybe some issue with the text rendering or the display calibration. Anyway, I reinstalled everything (same OS) and set everything up again from scratch and now it is fine, no problems.

                                  After the problems I had with the Moto phones and the Fairphone 4 and the problems others are reporting with other modern LCD phones like the Moto G75 which seem to cause eye problems even when they don't have PWM plus the ongoing trend towards OLED displays in phones, I begin to wonder if this Nord CE 3 Lite 5G may be the last fully usable phone for me. Since I also need an unlockable bootloader, which is now offered by relatively few manufacturers, and either close to stock Android default OS or custom ROM, my universe of usable phones may soon shrink to nothing. With that in mind I decided to buy another Nord CE 3 Lite 5G so I have got a spare in case anything happens to my daily driver. With luck these two phones might last me ten years if no newer usable phones emerge.

                                  I did flicker-test my second CE 3 Lite 5G BTW and that one too is flicker-free.

                                      George357 I stand by my original conclusion that the Nord CE 3 Lite 5G is flicker-free, at least the one I own is

                                      Recently my twitch app in android TV become laggy and I updated it from 7.0 to 12/13 version, and got eye-strain. I checked ver by ver and found 9.0 is last I can use, but it also laggy.

                                      Old one is 150mb, new is 60 mb. Using apktool I found old use exoplayer2, when new idk. IDK what does they change, coz "dither" keys looks more activated in 7.0 code version than in 12. And I think they switch internal player which use dithering

                                      p.s. making a backup - a very good solution in our case

                                      Using old/used phones is not good idea:

                                      1. The battery is worn out - you can replace it with a non-original one

                                      2. The memory is worn out - no solution

                                      3. The screen is worn out, the blue peak becomes higher than at the beginning, the screen becomes "cold" in shade - no solution, because it is impossible to find a new screen. And it is unknown from what LEDs / spectral the screen replicas are made. And it is unknown in which replica there will be FRC/dithering and in which - not

                                          11 days later

                                          simplex An old phone is better than no phone! And unless there is a radical breakthrough in DC dimming tech for OLED, that is the situation I may find myself in a few years from now. Fewer and fewer phones have LCD displays, only some of those are PWM-free and, as we have discussed, even those cannot be relied upon to be usable for us.

                                          Besides, old phones are not necessarily worn out, both my Redmi Note 8s are in great shape, good battery life still, displays look fine. And they are both nearly five years old. I do try to take care of my phones, slow charging only, limit charge to 90%, recharge when battery drops to 20%. I could have carried on using them for years, I think. I only changed to get an upgrade - phones do become outdated because technology improves over time and software becomes more resource-intensive with every update so old phones start to seem slow even if the hardware is working as well as ever. The CE 3 Lite 5G isn't the fastest performing phone but is a useful upgrade over what I had before so good enough for me. And should last me a good few years.

                                            dev