On the other end is motion stutter on OLEDs. Because of sample-and-hold, the blur goes away but the image stutters on slow moving scenes instead. If your eyes are sensitive to PWM (mine are) it's quite annoying to watch OLED movement as well.

After I had a psychosis (it was still 'active' at the time, in hindsight, but not as severe) I couldn't use a monitor for long, especially not gaming. It gave me immediate motion sickness, or made the headache more severe. Hw was TFT 1080p LCD screen, GPU was probably AMD 7770 HD, since a few years afterwards I replaced that with a Nvidia GeForce GTX 960.

My matte MBP 2010 didn't yield me this issue, but I didn't game on it either; just watched movies/series. A lot of them.

I grew up with CRT monitors though, and these could cause severe headaches. Especially if resolution too high.

curious; do you mean like a red plastic see-thru filter applied on top of the screen (filtering the backlight too, like those screen protectors), or a software screen effect that makes everything on screen appear red (which on an OLED screen would probably be the same thing)?

red/blue/green detectors (cones) in our eyes use different paths and have different "refresh rates" than luminous intensity sensors (rods), im wondering if filtering to a single color makes the rods take over for visual pattern processing

The change in that study was dramatically different: they had half the screen black and half white and were flipping which side was which at that rate. Yes, most people could perceive that. The study included 10 participants, all in their 20s. They didn't ask about headaches other observed effects afterward.

I have one of these laptops, I tried waving my hand in front of the screen at 50% brightness and I don't observe anything unusual.

I think I am pretty insensitive to this effect, though. Other than occasional seeing a bit of 60 Hz flicker out of the corner of my eye from Christmas lights, automotive LED tail lights, etc. I don't tend to notice flicker.

I am sensitive to PWM, but not CRT's (I have an old Sony CRT I use to play retro games). The reason is that CRT's do not turn the entire screen on/off like PWM does, they draw scanlines. This isn't nearly as bad as what PWM does. It's the on/off of the entire screen rapidly that is the issue.

In fact there is research being done in the retro gaming scene of using CRT-like scanline drawing to mimic what CRT's do for modern displays. This allows "blackframe like" insertion without the flicker. Only issue is you need a very high refresh rate display to take advantage of it and there aren't many of those.

I do have issues with PWM everywhere myself while CRT was not big issue. I did tinker with refresh rates though. And I think difference is that

1. CRT display phosphors had afterglow.

2. the cathode ray was a dot moving across the screen, that might be easier on eyes than whole OLED screen flashing at once.

I notice PWM all around me all the time. Lots of cheaper LED lights use it, and I see it whenever I move my eyes, also when not consciously looking for it - instead of a blur I see series of lamps as a brief afterimage.

As a child I got headaches from CRT monitors at 60hz and I could see them flicker. I haven't noticed the PWM on modern monitors, but maybe these Apple ones would trigger me?

Given that we discovered in the nineties that CFL tubes were unhealthy for a significant portion of the population at these refresh rates and changed to over 30kHz I would assume the same holds true here. In other words: more than we would have thought.

This has been an issue for all Apple OLED displays since they came out. I bought the iPhone Mini when it came out but couldn't stand it because of the PWM on the display. I had to get an SE instead which used an LCD display.

I'm one of the ones who is very sensitive to this. I get occular migraines often. It has become fairly difficult to find displays that don't have these problems as everyone moves to PWM dimming on everything. Even lightbulbs are a difficult purchase for the same reason (at least Ikea makes some that have zero flicker and are cheap).

I would say most people are actually sensitive, and report eye strain faster when using a specifc type of display, but don’t make the connection.

It's likely to impact far more than .0001% of users. I'd put it closer to 12% - roughly the same percentage of the population that suffers from migraines. Granted, the degree of which it impacts the person will vary, but if these displays earn the reputation of triggering them, migraine sufferers will steer clear.

It's hard to put a number on it (e.g. do people with eyesight problems or headaches actually know it's their display?) and it may also be influenced by other factors. I have used phones with 240Hz PWM dimming for years and haven't had an issue. However, I quickly get eyestrain when looking at e.g. a Samsung S26 Ultra. It's probably the combination of 240Hz PWM, FRC for emulating 10-bit on an 8-bit panel, and maybe the two types of pixels (narrow and wide, for the privacy display) that makes it painful for me.

I can also imagine that lower frequency PWM dimming can be more problematic on a display that covers a larger portion of your sight. Many people also probably use their laptop/computer screen for a longer time without looking away (aside from phone addicts).

.0001% is not nearly millions. They don’t sell billions of units

PWM sensitivity has been an issue on the iPhone for a long time, but the prevailing wisdom is that it affects only a small percentage of users, and then only at certain lower brightness levels. Consider it like a food allergy, we don’t rearchitect the entire food supply for everyone around the sensitivities of a few.

That said, I have my doubts about prevailing wisdom being true here.

A small aside: this is why I truly hate when people argue 'oh well, his only happens in 1% of cases, it's not worth supporting/solving'. With sufficient scale, and even without sufficient scale, it's thousands or even millions of people!

Wait... so operating at 100% brightness mitigates this? I bought this mac and have been reading about this. Stare at computer 15+ hours a day coding, but I also never use anything less than 100% brightness.

The "99% brightness has flicker" thing seems like a gaffe, but the general approach is common for low brightness levels.

I was going to downvote this, but instead I gotta say, what goes around comes around.

Don't forget the OLED stutter on slow moving scenes because of sample-and-hold. It's why motion interpolation (soap opera effect) exists. I can't watch OLEDs because of it. Looks horrible.

I like my OLED watch. I like the high contrast... it's a small screen but I haven't noticed any degradation over like 4 years.

LCD most certainly has color degradation. About 8 or 9 years ago I was able to compare a almost brand new surface pro 5 to my 3 year old one. I was shaken by the difference in difference.

I've 100% had LCD panels with burn-in, ghosting, and color degradation within the warranty period.

> Did Apple just forget about accessibility

To this day on macOS, the font size accessibility setting only works on first-party apps!

Even when using Apple's own UI frameworks, and using semantic font sizes that do actually scale up and down on iOS / iPadOS

It astonishes me!

PWM frequency is not selected in a vacuum. The maximum is set by your transition time which is set by a bunch of other engineering decisions. It's possible that something about tandem OLEDs make them more difficult to drive faster edges on.

Slight aside. I was thinking of buying a Google Pixel 11 but I learned that they have the same problem. I will go into a store and see if the Pro version (which can do 480 Hz) is OK.

Even if I'm not sensitive I am wary of this, what if it causes subtle eye strain that has long-term consequences?

OLEDs commonly flicker at some small multiple of the refresh rate because they often use something somewhat similar to DLP bit-plane modulation to avoid non-linearity at low brightness. You can't do that at xy kHz because that would require xy kHz scanout to the panel, which is physically ... not very plausible. You can gate drive current, but then you're back to how a 2010 LED backlight operates.

This: https://www.notebookcheck.net/fileadmin/Notebooks/Apple/MacB... is perceptually very different from a low frequency low duty cycle PWM you'd get out of a cheap LCD backlight.

All OLED iPhones flicker below some brightness threshold, for example.

I Think Apple gets progressively worse and worse and I mean in a general way. There are some anomalies there and there but overall the direction is a slow decline in details and quality.

I love me some high end electronics that doesn’t feel cheap but soon it will be not worth it.

Ok but who can actually see 240hz?

Like CRTs scan slower than that, and almost no-one could say they could see the pixels being drawn.

Sure you could hear those fuckers, but not see them, unless you had a source of vibration nearby.

Howe much of this is measurable, and how much of it is similar to the Himalayan salt lamp stuff?

Forget, no. Liquid glass? They've abandoned accessibility.

OLED plus dark mode is a way to juice advertised battery life.

Stopped reading after the first paragraph, straight AI slop aimed at SEO

Hard agree. This in particular got me to stop reading the article:

> At 240Hz, the brightness fluctuation repeats 240 times per second; at 14,880Hz, it repeats almost 15,000 times per second.

Was that written for people who don't know what "Hz" means, or who don't know that 14880 is almost 15000?

On the other hand, the first version is always the most hackable.