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When I actually went to the source for the 240hz claim, I didn’t reach the same conclusion as the testers?

Maybe they just let their rigol scope spit out 240hz, but 480hz worst case and I would actually say 960hz. I think what’s happening with the tandem oled is they both pwm at 480hz and 180 degrees out of phase giving effective 960hz when both are in use. Which appears to be most of the usable brightness.

Edit: I’m so confused.

“The PWM behavior is interesting, because we can see DC-dimming for all brightness levels. Usually, OLED panels use DC-Dimming only at higher brightness levels. The frequency is very low at 240 Hz, however, and this might be an issue for sensitive users, despite the DC-dimming. ” https://www.notebookcheck.net/Amazing-OLED-panel-Apple-MacBo...

I'm glad that this is bringing attention to flicker sensitivity.

Here are some other things that people are sensitive to: - CRI on white LEDs (and flourencents). CRI is how clean the spectrum is in comparison to the sun or a incandescent bulb, where the specturm is completely even. There are some CRI >=95 LEDs that are fine for most people however.

- Motion blur Motion blur on LCDs (such as ~50% of Nintendo Switch 2s) can hurt eyes trying to keep track of what is going on.

As someone who’s had a concussion, this is really interesting. For me this is how any screen was to me, not just bright OLED ones. Even more interestingly it’s essentially only screens— backlist posters at the mall (paper with a backlight) still affect it but less so. To me perhaps it’s focusing on something on a screen that does this, but it’s really interesting to see this affect the general population.

It’s also odd to think about lack of ability to concentrate, and I wonder if screens cause this optically somehow but to a less noticeable degree even when less intense than this new one? (Independent distracting contents)

I noticed that adding a severe red filter to all my screens helped me significantly with the concussion and am also curious about that, would that impact the intensity of a refresh perhaps? Is blue light specifically the problem? I’m unsure but have a plethora of subjective experience.

I’m glad for this to enter public consciousness a bit and would love to see more research on the screen itself impacting our brain.

I am shocked that Apple would release a screen with such a low PWM frequency. Here is a paper showing humans can perceive flicker at frequencies more than double their display’s rate: https://www.nature.com/articles/srep07861

I'd love for more research to be made into PWM sensitivity, if only to find out roughly how many people experience problems with it.

I've never had issues with it other than when trying to film certain old displays, but then again, I've never had issues with PAL TV sets running at 50 hz interlaced, nor even old PC CRTs running at 60, which definitely was not 'flicker-free', so I'm probably on the far end of the spectrum compared to the PWM sensitive.

It's an easy thing to forget, as with many accessibility features. And it's going to suck to have the nominally best display be one you just can't use if want to not feel like gouging your eyes out.

If it’s as low as 240hz, anyone will see a stop motion effect by waving an open hand in front of the screen at 50% brightness.

I’m curious if this is a harmonic mode for a high speed PWM where pulses are either not even widths or the driver loses some power at the 240hz cycle. May perceive similarly.

I have a couple windows laptop workstations with high dpi OLEDs (one with 240hz refresh rate) that I love and don’t perceive this so I’ll have to check.

I'm surprised by Apple putting out a laptop display with slow PWM. That's the kind of detail Apple has a reputation for paying attention to when other companies don't.

I'd be fascinated to see how common this really is. Is it something that affects .0001% of users, more, less? At Apple scale an issue like that could hit millions of people. Given the newness and expense of the product one would assume not that many OLED Macbook Pros have shipped. So it's surprising that this issue didn't come up in testing if we're talking about more than a handful of people.

You're looking at it wrong.

I’ve experienced the same issues on an iPhone 17 Pro. It took weeks of eye strain until I discovered the cause. Even if a small percentage of the population is affected this might still be millions of people that are unknowingly experiencing unnecessary eye strain or headaches from this

The whole "OLED is better" narrative... for starters LCD has longer lifespan, no burn-in, no color degradation. I don't ever want an OLED in anything.

I was expecting to read this and learn that the display was reasonably engineered and that there is some small subset of people who have extreme PWM sensitivity who have problems. But no, Apple modulates at 240Hz, according to plenty of articles.

We’re no longer in the dark ages of flicker. There’s actual industry guidance: IEEE 1789. And 240Hz, at any respectable depth of modulation, does not meet the low-risk limit, let alone the no-observable-effect limit.

I am wondering whether this is actually just an amazing firmware goof: the reports seem to suggest that operating at full brightness mitigates the problem, which makes little sense for an OLED display. An OLED showing 50% (post-gamma) gray ought to drive the pixels the same way as an OLED at 50% brightness showing white. And this display supports HDR, so even 100% brightness white isn’t really 100%.

I’m wondering if a little engineering mistake snuck in: some (most?) LCD displays dim by PWM-dimming the backlight, and plenty of backlights have current-to-light transfer functions that inherently low-pass filter the light. If someone naively ported the same logic to an OLED (which doesn’t have a backlight), they might have implemented brightness controls by applying a 240Hz envelope to the pixel excitation waveform. This makes no sense at all as an actual implementation, but I can totally see an AI doing it and writing tests to validate it :)

Even if there is a genuine engineering factor that requires low frequency PWM, I bet Apple could mostly mitigate the problem by deliberately mismatching the phases. For decades, pre-LED stadium lights had rather extreme flicker at 120Hz, but it was tolerable because the overall system was engineered to roughly evenly split the lights between three electrical phases, giving an effective modulation depth near zero.

I haven’t seen one of these displays myself. I find 120Hz flicker to be extremely obvious and very very unpleasant, and if these displays really do modulate in a nasty way at 240Hz, I expect I’ll be able to see it, albeit rather less obviously than at 120Hz. Also, pretty much any modern phone can see this in slo-mo video mode :)

This is bad.

I had to return the Steam Deck OLED and LCD because their displays PWM was burning my eyes out. Sore eyes for days, having problems to focus properly. I hope this is a learning process and it will get better from the manufacturer side. But I hoped that after my personal Steam Deck fiasco as well.

I thought OLED was superior the bee’s knees, but not at all are equal, single OLED is subject to burn-in and longevity problems, but tandem OLED is supposed to fix both of those problems. Tandem OLED is also a more expensive screen, the bigger it gets oh well. (It’s a great screen on the iPad M4 Pro). That’s the way the cookie crumbles?

Another alternative, that Apple offered on their desktop screens was simply a higher resolution 5K or 6K XDR screen, which are some of the better screens you can get on a desktop computer depending upon what you are using it for, and I don’t mean to play time wasting games.

Single OLED in particular despite all its problems, is the favorite of gamers in the PC world. The previous screen, Apple offered actually is a better screen top to bottom… I prefer the 6K XDR but it and 5k despite being great screens have never been cheap. (the Internet is filled with people crying about the price most of whom thought Apple should sell it at the price of a cheap 4k screen). You got what you paid for which is a great Apple screen.

https://www.youtube.com/watch?v=H43wnV-v7V0 Single OLED isn’t good enough long term. (Gamers will however claim it’s OK. 9 hours a day is 3285 hours in a year.

I had the same problem when the switch from CRT to LCD screens happened. I would get very dizzy when using them for a longer period of time. Other people looked at me funny. A lot of the LED bulbs are also flickering and can cause this issue. You can use the phone camera in pro mode to change the shutter speed to something like 1/8000 and it will show you the flickers.

Recently I switched from a 1440p IPS display which had no visible flickers on camera to OLED which has the flicker and the issues of headaches and dizziness came back. I can sometimes get used to it, but it's still straining more than the previous display did.

Yeah 240 is not a lot. I'm very happy with my new Honor phone that does pwm much better than Samsung. It does more than 2000Hz and way more than my Samsung around 480 I believe (or 240 even? I don't know). My Samsung watch 7 is especially bad, I can literally see it flicker, it's terrible. I take it for granted because a smartwatch isn't something you spend hours staring at. But a phone with that frequency would be unusable for me.

Ps the reason DC dimming isn't used so much is because at least with white LEDs the color temperature tends to change when the DC level changes so it's complicated to calibrate the screen accordingly. In particular the screen gets warmer at lower settings. This can actually be welcome because these settings will be used more at night and a lot of people prefer warmer settings then these days. But it's something that the user should be able to control.

Not sure if this applies to oled too though.

Is this something one would notice if they don't have problems with OLED phones? I was a bit worried reading this...and then realized I was reading it on a Pixel 8 on low brightness. Did a search and found reddit comments like: "Google pixel 8 is the worst when it comes to pwm. It has a frequency of 240 hertz which is the lowest in the industry." [1] I haven't noticed unusual eyestrain using this phone, so I'm hoping a new Macbook Pro screen also would be fine, despite its larger size.

Back in the CRT days, it always bugged me when a display's refresh rate was down at 60 Hz, but otherwise I think I'm not too flicker-sensitive.

[1] https://www.reddit.com/r/PWM_Sensitive/comments/1f9j3fi/pixe...

I know that each one of us has different peculiarities about screen quality (some care more about colors, others about refresh rate etc).

My personal feud with OLEDs, is that even at very high resolution the fonts do not look as smooth and creamy as the equivalent IPS. It is like I can tell apart their subpixels.

For example I prefer text on my old iPhone 8 compared to my iPhone 17.

Despite people perceiving this differently your sensitivity can also change over time.

My first computer had a 50 Hz (Hz not kHz) color monitor I spent hundreds of hours in very close proximity with and the flicker did not bother me.

When I fetched the machine from the attic some years ago and tried it I could not bear it for long.

It's hard even for myself to grasp, how my own perception could have changed so much.

macbook pro displays (before the oled) have always caused a weird sort of eyestrain and become hard to read after a few hours of usage for me. i have never pinned down exactly what causes it- some internet threads talk about "temporal dithering" complete with weird extensions that may or may not disable it. sometimes i wonder if it's the glossy display (although oddly sometimes it appears to affect me with external displays). i don't know if it's the glare from the gloss, the antialiasing of the fonts or something about the refresh? i have played with all the refresh rate "pro-motion" knobs, it doesn't seem to matter. many of my thinkpads have used pwm dimming, so it's not that. it has been an issue for me on both intel and aarch macbooks.

it would be interesting to get a high speed camera and see if there's a difference in the temporal dimension as well as a careful analysis of the font rendering. it would be funny if there were some kind of metamer noise in there or something that only some people have sensitivity to.

i would also be curious if the matte display option solves it (or has solved it for anyone else).

The article does't mention which models may be affected. Is it all the M series?

Seriously cannot believe the PWM frequency is 240Hz. I was shocked out of my mind when I first saw that. It needs to be on the order of kHz to avoid eyestrain for a very significant proportion of the population. Did Apple just forget about accessibility, or did they underestimate it?

Really happy this is getting people's attention.

I got sensitive eyes and can sense even previous gens' pwm at 15kHz. At 240Hz, I can probably see the pixels turning on and off! Only joking obviously. But I can definitely perceive the unstable luminosity. I can easily spot the OLED screens from 15ft away.

Definitely not going to upgrade. Sadly, this is most likely going to be the standard for Apple going forward.

Looking forward to the price going down and perhaps a good refurbished deal.

The only use case I can think of for this machine is testing iOS touch interactions without a physical phone. Just this one specific purpose and it's not one that would require prolonged use.

Interesting it seems hard to find any research that concludes 240hz or higher frequency flicker causes physical discomfort. Is there a single paper that concludes this? Older studies were based on ~100hz fluorescent lighting.

In a rigorous blinded comparison, would the new OLED MacBook cause more physical discomfort than the mini-LED model? How to explain all the symptoms being experienced?

What’s most likely?

1. Real MacBook hardware issue

2. Nocebo. Expectation of PWM problems > real physical symptoms

3. False correlation. Real headaches/eyestrain but from other causes

How surprising would it be if the answer is not (1)?

Latest iPhones have similar issues with PWM. Does Apple ignore these display issues? I assume it is not a priority given their engineering teams could find solutions.

Does anyone know if this is something that can be addressed in firmware or hardware?

For example, could we overlay a software dimmer while driving the panel at max brightness?

Or would it be possible to tune PWM settings from the OS?

Or would this be possible to tune with a firmware change?

Idk how these things work.

Given that my phone still suffers from burn-in even though the industry keeps alleging that it is "a solved problem" + given that people adore macs for them being usable for a decade or so, the choice of OLED for a laptop like that seems weird.

It's interesting but unsurprising that now _more_ technical issues creep in, given that the whole idea fundamentally was flawed. If given the necessary technical scrutiny, it would not have happened. Hence, that must've been disabled. Hence other such blatant oversights like this one became much more likely, given that any voice saying "dumb idea" was already pacified.

I of course have no idea how this actually went. I am just claiming that my headcanon is canon.

240hz is insanely low.

If you want to use PWM in an application like this you need to start at like 600hz. This is how fast the subfield drive on a plasma TV is.

I have to use incandescent lightbulbs for certain fixtures because I sometimes need a break from engineers who think they are smarter than me.

The shell is 1:1 to a mbp. I predict the following things will happen. Water damage- folks using their semi dry hands to touch the screen- that water is going to drip straight down to the logic board! Injury- those sharp corners at the top of the keyboard are just waiting for a power user to swipe. Screen separation. Touch screens were made with durability in mind- the hinge on the touchscreen mbp is identical in range to the stock mbp. Can’t wait till gen 2

i could not use OLED screen for programming and > 4h screen time a day. too much strain on the eyes. i have LG Gram laptop and it has really good IPS 2560x1600 panel with great color coverage. but it's hard to find a good laptop with IPS screen today as OLED is almost everywhere now.

I am not particularly sensitive, but switching the ipad pro for the oled model, I just don’t like the screen that much, and it is hard to put the finger on why. Side by side, the screen has better blacks and peak brightness and I am sure it beats the LCD empirically on many metrics. But I don’t like the colors as much, and perhaps subconsciously, the flicker is turning me off.

TIL

IMO this is very typical of modern Apple. Doing something amazing, but nerfing it ever so slightly so that its just not as great as it could be. I feel this started around the time of the butterfly keyboard issues and terrible cooling solutions on the last intel macs. It just doesnt seem to be getting better, there is nothing they release now that just wows everybody full stop with no comeback from anyone.

Is this flickering of similar nature as "sport motion smoothing" on TVs which makes every other frame blacked out?

In my experience, Apple hardware always gets better over time. So, you should never buy the first hardware "innovation" changes that they do.

somewhat relatedly, i would just like to raise awareness of coil whine for those sensitive enough to hear it. i wish high-frequency tonal noise was also disclosed in the specs, if not part of QA...

On the one hand, I have never heard anyone complain about the 24hz flicker of a film projector.

On the other hand, half rectified LED christmas lights have noticeable flicker to me and can make me feel irritable and woozy.

My question is, when it's trivial to create a PWM circuit that switches at 20khz or higher, why do manufacturers continue using anything in the 60-500hz range that people seem to notice and complain about? Do they save 2 cents or something?

Better isn’t always better right away.

I also wonder how it will fare in terms of burn-in. OLEDs are infamously susceptible to burn-in.

This is one of the worst articles in terms of information per word density! Too many words and so much beating around the bush before it even discusses what the heck it's talking about.

If only there were some way to see the display in person and see if it interacts with your, whatever problem, unequivocally...

>We don’t know why Apple has ended up with this particular dimming behaviour

We do. This is more shortseller scamming and market manipulation. They lay their thesis out in this sentence:

"Bad customer experience is usually Apple’s Kryptonite."

The entire domain macanorak.com is shortseller fraud/scam, just like the fake emails pretending to be Jensen Huang's board of directors. His board is furious.

The shortsellers are trying to triple up on their scam. (They tanked Nvidia's stock by 20% in 5 days, wiping a trillion dollars off of its valuation, so now they want to triple up on their fraud by doing the same thing with Apple.)

This is criminal fraud. A quick read through of this domain is all it takes to see through the scam.

> But some people are particularly sensitive to this kind of modulation and can experience eye strain, headaches and other forms of discomfort when looking at displays that use it.

So that tiny fraction of users would be well served with some other display and can either return their MacBook or use an external monitor if and when they find out that they're in that cohort.