Do you know flickering at low brightness levels on your iPhone? Apple is now introducing a PWM deactivation option for the first time. We explain how “display pulse smoothing” works and why there are compromises.
New PWM option should alleviate eye problems
The iPhone 17 models have a new barrier-free setting for deactivation of the pulse width modulation (PWM), as information from the iOS 26 release candidates show via Appleinsider). This function is intended to help users suffer from screen flickers that have caused problems since the iPhone X. The new setting with the name “Display Pulse Smoothing” is located in the “Display and Text Size” area of the barrier-free settings and can be switched on or off.
According to Apple, the new option works as follows: “Deactivates the pulse width modulation in order to offer a different type of OLED display dimension that can create a more even display output at low brightness levels.” It is Apple’s first integrated option to reduce OLED fibrillation.
What is pulse width modulation?
PWM works for brightness control by switching on and off and switching off LED or OLED pixels. With OLED displays such as in the iPhone, the brightness control and color mixture is reached by rapid on and off individual color cells. At full power, a color cell has a 100 percent switch-on time and is completely light. To reduce the brightness, the color cell is quickly switched on and off at a fixed frequency.
A 50 percent work cycle means that the cell is switched on or off half of the time and appears about half as bright. This effectively leads to a stroboscope effect for the user. Some users are disrupted by PWM and can make flickering at lower brightness levels. Affected users often complain about eye problems, headaches and other symptoms, although it is an energy -efficient technology.
Availability and restrictions
Apple confirmed that the setting for PWM deactivation is available for all iPhone 17 models. However, the company warns that the deactivation of PWM can affect the display performance in low brightness under certain circumstances. PWM has been used in OLED IPHONES since the iPhone X and is of crucial importance for screen operation.
The new option could be a significant improvement, especially for sensitive users, even if it may have compromises with the display quality. Users have long been looking for such a solution because the PWM-related problem has been discussed for years.
