Have you ever heard of PWM (pulse width modulation)? Even if you haven’t, this screen flickering issue still might impact you. But iPhone 17 looks like it will bring a long-awaited PWM fix.
PWM can be disabled on iPhone 17 models
I had never heard the term PWM before today, but as I learned by visiting the ‘PWM Sensitive’ subreddit—which has 16k weekly visitors—it’s a fairly widespread issue, and has been for years.
Pulse width modulation is a tactic used by smartphones when brightness is reduced.
Essentially, the phone’s OLED display keeps all pixels on at 100% brightness, but at 50% brightness it’s rapidly switching them on and off in a way that most users can’t discern.
For some people, however, PWM might result in a screen flickering effect that can cause eyestrain and even severe headaches.
It turns out, Apple has a solution coming with the iPhone 17, as discovered by Aaron Perris.
The iPhone 17 Pro (and maybe other models) have a new setting to disable PWM:
“Disables pulse width modulation to provide a different way to dim the OLED display, which can create a smoother display output at low brightness levels. Disabling PWM may affect low brightness display… — Aaron (@aaronp613) September 10, 2025
... continue reading