concernedcoder
I’m working on trying to figure this out. You’re not the first person to have that experience. I did some quick research and the two things that pop out to me is the LG C3 is WOLED compared to the iPhone 16’s AMOLED and the iPhone 16 is over 3x as bright as the C3. C3 has lower PWM, though.
We know the modern iPhones (anything after the iPhone 13 and 13 Pro, or anything manufactured after 2022, including the rewaved 13 base for 2023) are using different hardware and iOS 16 and up likely dithers depending on the phone and version.
I think at a certain point we have to move beyond “does this phone or computer have PWM” or “does this dither” and start evaluating flicker at a frequency level as well as identifying the frames inserted and how it affects pixel behavior. There are too many examples of people being able to use devices that shouldn’t work, but do. We have to be missing something.
I think the reason why dithering is so problematic is because temporal dithering and FRC specifically is limited by the display’s refresh rate. Thanks to some patent documents we know Apple’s GPU dithers up to 4 temporal frames per cycle so on a MacBook Air it should be dithering at 15Hz, well within seizure range, if my math is correct: 60Hz / 4 frames = 15Hz. That’s such a dangerously low frequency that it’s no wonder a few seconds or minutes trigger migraines or seizures or other neurological issues in sensitive folks. But because it’s “hidden” it’s not readily apparent.
From what I’ve seen most phone OLED’s tend to be 10-bit, or if they’re not they’re pretty darn close that they shouldn’t have to dither much to display P3 colors. The mechanism is also different than LCD just by the nature of how OLED’s work, so I’d imagine the effects will undoubtedly also differ. The problem with the iPhones is we are dealing with 2 PWM frequencies, 2,000 nits brightness, variable refresh rate ProMotion on the Pro models, and whatever iOS dithering is occurring. Once you start upgrading an iPhone 13 to iOS 26 you’re 4 generations of OS out from what it shipped on (iOS 15) and anything past 2 generations is iffy on older tech.
But to answer your question it sounds like the brightness is a major trigger for you. The LG C3 is something like 650 nits max brightness and you’re sitting far away from it yet the new iPhones are 2,000 nits and you’re holding them inches from your face. And if you lower the brightness of the iPhone 16 to match say 50% of the LG at 300 nits you’re triggering a 60Hz PWM frequency with seriously bad modulation, so you’re gonna get nuked by that flicker.