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?

▲

MYEUHD 2 hours ago | parent | next [-]

> 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!

▲

willis936 2 hours ago | parent | prev | next [-]

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.

	▲	esperent 2 hours ago \| parent \| next [-]
		Lenovo Yoga Pro 9i has a tandem OLED with 1200hz PWM. https://www.notebookcheck.net/The-new-Tandem-OLED-panel-in-L...
	▲	LoganDark an hour ago \| parent \| prev [-]
		Do slower pixels prevent you from using a higher PWM frequency? Wouldn't that make them like a capacitor smoothing out the high frequency signal into a constant one, like in a Class-D amplifier? That would reduce strobing even more!

▲

techpression 3 minutes ago | parent | prev | next [-]

I have no idea, but could it be battery usage and their adaptable update frequency, or a combination of both?

▲

gniv an hour ago | parent | prev | next [-]

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?

▲

formerly_proven 2 hours ago | parent | prev | next [-]

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.

▲

api 2 hours ago | parent [-]

TIL there’s a pretty serious downside to OLED. Love the contrast ratios but not this.

I’m not super sensitive to flicker but can be annoyed by it. I’ve used OLED phones but it’s probably not as annoying on a small screen than one that covers more of your visual field.

▲

formerly_proven an hour ago | parent [-]

If you go in a dark room and set the brightness of an OLED phone to minimum and then just swing it around in front of your eyes you're very likely to see a stroboscopic effect. For iPhones this seems to become noticeable below about 20-30% brightness.

	▲	katbyte 36 minutes ago \| parent [-]
		I guess I’m not sensitive to it as I did not have this happen. iPhone 16 pro.

▲

juleiie 2 hours ago | parent | prev | next [-]

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.

▲

LoganDark 2 hours ago | parent [-]

They have certainly been in decline ever since Jobs died. I really hope Ternus can flip it back around.

	▲	juleiie 2 hours ago \| parent [-]
		It’s still many times cheaper to overhaul Apple than to start another company from scratch. They still have the right ethos, philosophy and past traditions engraved in the History of the company. Someone just needs to remind them what are they supposed to be doing.

▲

KaiserPro 2 hours ago | parent | prev | next [-]

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?

▲

mrob an hour ago | parent | next [-]

The problem isn't the flicker directly (240Hz is above the flicker fusion threshold), it's the phantom array effect when you move your eyes. Static images transform into a series of overlapping images, and this can be annoying and distracting. It's visible well into the kilohertz depending on how strong your saccadic masking is. I can personally see PWM up to about 10kHz (tested using a strobing LED).

AFAIK, all OLED displays have PWM flicker, and for this reason I stick with LCD, where flicker-free displays are available (although PWM flicker is present in some LCD displays too).

▲

Y-bar 2 hours ago | parent | prev | next [-]

Fluorescent tubes used to run at less than 100 Hz before scientists discovered that that was unhealthy for many. Now they run at 30-60 kilohertz.

▲

rayiner an hour ago | parent | prev | next [-]

I can easily see at least some PWM LED headlights flickering in my peripheral vision (which is more sensitive to flicker).

▲

LoganDark 2 hours ago | parent | prev | next [-]

It's not about whether you can "see 240Hz". CRT phosphors have sustain, while OLED does not. The fully-on, fully-off cycle, if infrequent enough, causes some sort of visual stimulation that some brains absolutely do not like. You don't have to see it to feel it.

Sometimes I can tell flickery fixtures because they just "feel more staticky". I don't get visual eyestrain or nausea though.

▲

mrob an hour ago | parent | next [-]

>CRT phosphors have sustain

Other than some old monochrome CRTs, all CRT phosphors decay too fast to prevent flicker. You get some softening of the trailing edges of the phantom array images, but they're not actually blurred together like on a sample-and-hold display. And even the fastest CRTs have fairly low refresh rates, making it more obvious.

▲

ZyanWu an hour ago | parent | prev [-]

> You don't have to see it to feel it.

It's not magic. :) You DO see it. 500 Hz for the median observer; above 800 Hz for some individuals. https://doi.org/10.1038/srep07861

	▲	LoganDark an hour ago \| parent [-]
		This paper appears to be about the DLP effect that happens when a strobing light moves across your vision. Similar, but not the same thing! There is still some ability to percieve strobing at a steady state though, even if the amplitude is reduced by visual persistence.

▲

2 hours ago | parent | prev | next [-]

[deleted]

▲

2 hours ago | parent | prev [-]

[deleted]

▲

kps 2 hours ago | parent | prev [-]

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

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