Last year, Samsung released a video explaining how screen flicker (which he defines as changes in brightness) can tire the eyescause headaches, eyestrain and even seizures.
While this ad was promoting Samsung’s OLED TVs, leaker Ice Universe took to his Twitter account to point out something interesting about how Samsung is harnessing this technology.
In their tweet, Ice Universe wrote: “It’s hilarious that Samsung uses a video to illustrate the damage to human eyes caused by flicker and touts that OLED screens are flicker-free (supplied to Chinese brands), but the Galaxy S22 Ultra and S23 Ultra are the phones with the more flicker“.
He follows up with another tweet that reads: “Oh, by the way, the Galaxy S23 Ultra also has the most eye-damaging screen among all mobile phone brands. It only achieves a PWM of 240Hz, which is lower than the 480Hz of the iPhone 14 Pro, and both are far lower than Chinese mobile phones.“.
Phone Arena / Phone Arena
PWMor pulse width modulation, is a technology that turns diodes on and off at different speeds. This technique, which turns the screen on and off, is how phone screens turn on. Manufacturers use it because helps reduce costsallowing devices to be sold at lower prices than they would otherwise cost.
Faster PWM means flickers happen too quickly to be seen by the human eye, whereas slower speeds can cause eye strain, headaches, seizures and eye pain mentioned above.
As Ice Universe points out, the Galaxy S23 Ultra uses a display with 240Hz PWM, which is half the screen speed of the iPhone 14 Prowhich has a PWM of 480 Hz. The Honor Magic 5 Pro’s 6.81-inch OLED panel will have a PWM of 2,160 Hz, far superior to its rivals.
Ice Universe posted the following example: “Imagine that there is an electric fan in front of you. When its speed is low enough, you can make out the fan blades spinning before your eyes. Your eyes will be tired, but once its speed increases, you won’t be able to see the fan blades…“
It’s worth mentioning that the Pixel 7 Pro has lowered its PWM to 240Hz from the 360.5Hz used on the Pixel 6 Pro display. The standard Pixel 7 has 360 PWM. For memory, the Galaxy S22 and Galaxy S23 ranges use 240Hz PWM, which could be why their users suffer from eye strain or headaches frequently wearing them.