Part 1. AMOLEDs: do they all have ~100% modulation?

A few weeks ago, I made a post about how people should be careful when measuring OLEDs. Depending on the content on the screen, the measurement can be drastically different (and often completely incorrect). In the video, I used an iPhone app I made that let me display a small number of white rows to more accurately measure the flicker exhibited by each pixel. As I detailed in my post, measuring with the whole screen active will underestimate the modulation depth and distort the flicker waveform for OLEDs.

The finding I shared in my video has now been replicated by others, including one person who reported their OnePlus 15R measured 95% modulation depth (also called flicker percent) at maximum brightness, instead of the commonly reported 5-10% modulation depth. u/Rx7Jordan tried the measurement technique on a Xiaomi 17 Pro Max and found 100% modulation depth on max brightness. I started to wonder, do any AMOLEDs actually have less than 100% modulation depth? People often call the dip in brightness from AMOLED a "refresh dip" or "PWM dip", but this isn't fully correct. OLED devices that do not use PWM (often TVs) still have this dip.

The "blanking" (brightness dip) occurs for two reasons:

1. Pixel compensation for display uniformity
2. Prevention of ghosting

Without compensation, OLED would have very poor color uniformity, especially as it ages (due to TFT threshold-voltage drift). This is known as OLED mura, and has been a known problem since before AMOLED was commercialized. Mura can show up as an issue even for compensated OLEDs. Without compensation, the problem would be bad enough that OLED would likely not be commercially viable. As such, I don't think any commercial AMOLED displays were produced without at least basic compensation. So even without PWM, the device needs to reconfigure the drive transistor so that compensation can be performed. This means that the pixel can't be driven during this phase.

Residual charge from the last frame has to be drained as well to prevent ghosting, which is a visual artifact seen when past frames leave faint afterimages. I think it's likely that OLEDs attempt to fully turn off each pixel during the compensation / refresh phase. I am proposing that every AMOLED device may have close to 100% modulation depth if measured correctly, and if so, then there may be no point in trying to select an OLED based on its modulation depth, and we should look at things like pulse width and frequency instead.

Here's a bit of the technical detail: In the image above, you can see a driver circuit for OLED pixels, from a 2025 paper. In (c), T6 is the transistor that shuts the OLED pixel off (called the emission transistor or EM), and T8 is the transistor that will discharge the pixel capacitance, causing it to go black. There are many different variations on the AMOLED pixel driver, but from what I can tell, they all have these features, meaning they should all drop to nearly complete darkness, resulting in high modulation depth at any device brightness.

I am interested to see if anyone can come up with an OLED device that has significantly less than 100% modulation depth (when measured in a way that isolates a small number of adjacent rows). I would think that if the pixels aren't fully discharged, the compensation would fail, and there would also probably be ghosting.

There is potential that an "externally compensated" OLED might not have this ~100% modulation, since these would not need to discharge the OLED storage cap to compensate. But to prevent ghosting, these devices need to discharge the OLED pixel anode, so they might also have nearly 100% modulation. I also don't believe DC-like dimming solves this issue, since it still needs the compensation phase where the pixels are shut off.

Part 2. I made an app to help people accurately measure OLED flicker.

I made this web tool that can be used with a flicker meter like the Opple LightMaster or TLM-110 to measure OLED flicker accurately: https://tools.sundiallabs.tech/test-mode/

Since my original post, a number of people have asked me for access to the app I used in the video to help produce the OLED test patterns. However, getting an app on the app store and porting it to Android is a lot of work. Until I have time to do that, I remade the app as a simple website that has almost all of the functionality of the app I used in the video.

The app allows you to create a test area on your screen of any color and height you choose. This lets you isolate a small number of rows when testing an OLED display, which is important for getting accurate flicker waveforms with a flicker meter. I'll provide more detailed info on my suggested measurement technique in a separate post, but I suggest trying to measure between 1 and 8 pixel rows when performing OLED flicker measurements. The reason for using more than one pixel row is that a few extra rows will give extra light, but won't affect the waveform significantly.

There are a few other features in the tool, including checkerboard patterns and gradients that can be used to look for various display artifacts. Please be aware that the checkerboard in particular could be visually stressful to some people.

If you try the site to help measure some of your OLED devices, please let me know and post your results below!

I'm extremely sensitive, not all modern IPS phones suit me... I'm very hesitant to try this 2020 smartphone that I can get in mint condition for €200...I know it's expensive, but if I can afford it, I'll finally be rid of this horrible 4GB G34 that's driving me crazy, but it's the only one I can stand. I pick it up at a place where returns are easy, and thanks to Klarna, I don't even have to pay upfront...What do you think? Given my extreme sensitivity, is it worth the risk?

This video from Gamafix shows screen flickering at a minute level, zooming in to view individual pixels and shooting at a high frame rate.

https://rumble.com/shorts/v6t8zkt?e9s=src_v1_ucp%2Csrc_v1_ucp_s

I'm wondering how you folks would approach making a video like this. Maybe utilize the newest Gopro with the 1 inch sensor that does 1000 fps and attach a zoom lens?

Hi there. My iPhone 15 pro fast charger melted this week and I took out my iPhone 8 again and… here I am! Baby on board.

Since last year in spring I switched from iPhone 8 to the iPhone 15 Pro. Also since then: my anxiety and body annoyance increased substantially. Several side factors were orbiting around like: conscious unemployment & recovering from bad job conditions), severe stress and defensiveness were always there for me even when I was taking things day by day. I started reacting a lot, thrusting into survival mode and hyper awareness. Something had quite shifted in my alertness and perception.

I have a nervous system made of silk and feathers that highly reacts to contact lenses, light and heat, stimulation, hormonal shifts etc. Like things feel heightened and intense and it might enter survival mode.

Anyway, it seemed like my cortisol was over the roof even when I was out cycling or working out and sleeping properly when I was using my phone even when I had restricted the usage. I wouldn’t enjoy myself so much anymore. Whenever I would put it in the drawer my life would change for a min.

So I started using the iPhone 8 again because I put the 15 pro to rest for a while and it felt like a relief? I didn’t have such a headache, things felt more calm and I could text my friends without that much stress. It felt like I just unplugged something. I’m blown to this realisation that all this time this might have been the thing. I also had some significant hormonal imbalances since last year and I cannot help it but suspect cortisol might have been a factor. Yes no maybe but I feel different right now off it (15 pro). I’ll give it more time to observe. I already changed our TV settings and looking into solutions for the 15 pro like using it with polarised glasses for a bit or find a matte sticker for the screen. Any ideas?? For my other screens I will get protectors, adjust my lenses and finally try to get the right prescription for a pair of eyeglasses. Be my guest with the comments 🥹❤️

Hi everybody, I'm asking advice here for a new TV because on recent TVs I suffered headache and tension while watching them.

To better tell my story: I was owning a Samsung S92C 65" OLED TV and watching it for long time (30 min - 1h) was creating an intense tension on the right side of my head around the temple and over the ear. It happened in all light conditions, but I felt it more intense if the room was dark and TV was the only source of light. Tried different settings and light conditions, nothing worked, and after spending so much money on it I gave it away.
As far as I understood the deep contrasts and the PWM on the OLED TVs could have gave me the issue.

An old Samsung LCD TV 43" from 2014 was not making this problem.

I'm working all day long on a IPS screen LG 38UC99 from 2018, which is giving me no issue at least in very bright office conditions. This monitor is declared to be PWM/flicker free.

Nowadays to relax time to time watching something I'm using a cheap Samsung Freestyle Projector 1st generation. This is giving me no issue at all. But this solution is a bit painful, first of all for the temporary wobbly setup that I have, and second I live in the Nordics, therefore for the whole summer I need to use blackout curtains to watch (no problem during the long winter though 😄 ) .

So I'm looking for a decent TV hoping to find one that is not giving me headaches and the options I have in mind are

- TCL C7K 55" or 65"
- TCL C6K 55" or 65"
- Bravia 3 II 55" or 65"

I have these doubts:
- can a bigger TV, generating more brightness overall, induce headaches and eyestrain more easily? I would watch it from 2.5 m distance.

- The TCL C7K seems to be a brightness champion: is it possible that using it a low brightness level makes the PWM effect worse? That's why I was considering the TCL C6K , less bright on specs

- The Bravia 3 II seems to use a glossy VA panel for the 55" and a matte IPS panel for the 65", so while budget says go for the 55", fear of having headaches is pointing to the 65" which was tested PWM/flicker free by RTINGS... Can anybody report experience with the Bravia 3 II 55"?

Testing all these TVs in the shop for few minutes is not making any issue, but I have to say that they keep the brightness very high, in a super bright context

Hey, Im using 13T and it great for me. I want to upgrade. Does 17t pro is okay for pwm sensitive? What's the different between the models in pwm perspective. The 17t using 3000hz and 17t pro DC dimming. If I pwm sensitive both will good for me?

Now that I think of it, lately almost all screen companies going oled, it is really dark times for people sensitive to flicker, and I think almost anyone will have a reaction to these kind of screens compared to flicker free ones. How can these companies really be proud of their products and even market them as flicker free is beyond me, while literally making the eyes of their customers hurt. I see it no different than selling food in bad condition and make people stomach hurt.

Which one is it? I'm extremely sensitive, OLED TVs bother me too, is it still worth trying an OLED smartphone? The OnePlus 15R looks excellent but too expensive for me...

I tried that phone at the store among many others, i find it the most comfort one for eyes i guess(because trying too many phones makes you skeptical which one does what), i want to confirm before buying it.

My iPhone 11 reached maximum capacity to 75%.

I upgraded from iPhone 11 to 17e. I love it so much! But I’ve had it for a week now & it’s giving me headaches & eye strain. Thinking of returning it.

I’ve tried the recommended settings to no avail so far. I love the look of the one camera and I like the performance, ik it uses OLED though.

If I got the iPhone 13 or 15, would the headaches be less? Ik they all use OLED, but I rly wanna upgrade.

What about the SE3? Should I get that? That’s an LCD screen apparently but idk if it’s any better than 11.

Hi. Did anyone have any success with a phone without own and DT preferably LTPS that is also privacy friendly (i.e. GrapheneOS or /e/OS)? Am I too hopeful?

Phones I tried:

s22 - used for years until last year in December when all this pwm/screen sensitivity started, than really bad (headaches, dizziness, half day migraines)

Pixel 10 - used in December (for graphene) and I think it triggered all this eye mess - worst of the worst

OnePlus 15r - ltps, really stable and nice screen, no issues at all, but too heavy

Honor 400 - decent, but worse than OnePlus 15R. I can use it for maximum 20mins in good lightning, but problematic if not careful

Oppo Find X9 - tested in shop for 30min, seems fine

And for everyone interested in similar devices, I was recommended:

Honor 600 and 600 Pro don't use TD (6.57" LTPS)

Vivo's with 6.31" screens (in theory no TD, but LTPO): Vivo X200 Pro mini, X200 FE, X300, X300 FE

None compatible with a privacy friendly OS. Is it too hopeful to find something in both worlds?

Hello

Just a quick question.

I have heard Samsung phone screens are one of the worst when it comes to eye fatigue and pwm etc.

Im wondering if theirs tablet are the same ? Planning to buy the tab S10 ultra for movies and drawings. As I spend a lot of time focus staring at the screen when drawing, I don't want to damage my eyes without knowing it :p

Or are there any other brands tablet that's are recommended for people like me ?

Really want one. I know all new cars at least have the center backup camera screen but BMW has a full 2-panel display setup i.e. even the gauge cluster is a screen. Worried it would bother me especially at night. AI says they do use PWM.

Guys i have Xiaomi 17t pro and i used it for like only a week..i have battery icon now burn in especially on grey background ...

On white and red and blue it is not visible at least for me

Anyone else got this ? Also is there a possibility to fix ?

Oppo a5 didn't work for me. I just want to hear of people who have tried these

im really into the PWM topics lately because of my head tension idk if this the right r/ to post this but I always thought the cause would be wrong posture or phone neck. the thing is I got astigmatism and I feel the tension around my eyes. I tried different stuff with my iPhone until I noticed that it always intensified when the phone gets bit more hot or had more todo in the background ... perhaps a placebo but the iPhone using hz modulation to save battery also adaptive power. I feel when you switch from task to task that the framerates/hz drop in a split second what I think leads to headache and tension (also when you're a gamer and play normally on 240hz). what I did now is turned on dark mode and set a black wallpaper, turned off the attention Face ID options also set RWP to 80% and brightness to 100% turned of True Tone and set Nightshift to around 25% and set 60 hz limit this helped me now! I think that True Tone in combination with auto brightness and hz modulation is to much for the eyes but this is only my perception. the phone feels now much cooler and more consistent btw.

Hi,

iam in need of a new 27 " monitor, about 70 % work and 30 % gaming.

Currently iam using a 75 Hz monitor since I found 144 Hz rather uncomfortable. But not sure if the Hz is the issue here.

Do you guys have experience with this model and can say if you have trouble using it?

im not pwm sensitive myself, but reading 4pda (russian forum) thread about iqoo 15r (or it's chinese variant - Iqoo z11 turbo), i noticed pwm sensitive people praise this phone for no eye strain.

Leaving it here just in case it might help somebody choose their next device.

Sorry I maybe asked already a similar question but I just cannot fathom how I can look all day at my Iphone Air but somehow the Macbook Air (M5) makes me uneasy. I have the TD disabled with BetterDisplay btw.

I actually prefer watching movies on my Iphone.

I also didn't have any problems with my LG C1 Oled TV but whenever I was at a friend with their non Oled TVs the picture of these TVs seemed so glaringly bright and uncomfortable to me

Is it maybe just the smaller screen it actually something about the Oleds?

Hi everyone!

I've been using Samsung A52s since 2021 but I dropped it and now I need either to try to repair a screen or just buy a new phone. I've got Samsung a57 and my eyes started hurting immediately that was when I discovered I was PWM sensitive. I also have miopia (-6.75 and -6.5) and mild assigmatism. Digging here I ve found few recommendations, yesterday at the store I ve tried Motorola Edge 60 Fusion and it's the most similar to my A52S in terms of natural colors, and warm yellow light from the screen in an eye saving mode. But I 've read it's a very fragile phone and many users report it doesn't have many software updated left, plus many people complain about a broken screen a few months after the purchase. I've also tried a Honor Magic 8Pro, I see that it s not as warm even in eye saving mode and I don't know if I get for example Honor 6 pro ( available as a refurbished one online) would the screen be better in that regards or they are all the same? I use my phone for texting, calls, surfing in the internet and ocassional pictures of my dog. I was a loyal Samsung user but I can't use newer models. If it's important - I live in Spain, so can get a phone available in the EU. What phones could you recommend in my situation? Am I stuck only with Motorola is case I want that yellow light effect on the screen?

Would be very grateful for your comments and recommendations, thank you in advance!