Why Pulse-Width Modulation (PWM) is such a headache

[Redaktion]

We often make a big deal about low-frequency Pulse-Width Modulation (PWM) in our detailed reviews of displays, but why is it such a negative? This articles takes a detailed look into Pulse Width Modulation (PWM) as a technology and why certain PWM frequencies can be harmful to people.

https://www.notebookcheck.net/Why-Pulse-Width-Modulation-PWM-is-such-a-headache.270240.0.html

[DG]

Excellent Article.
And thanks for testing for PWM on each device

[powerslave12r]

Thank you for testing PWM in all of your reviews. It's a life saver.

[Chris1232]

Thank you so much for including PWM testing in your reviews, it's very helpful !!!!!! I also had been using your materials and reviews to inform my friends about pwm, now some of them start to care about PWM when they considering to but phones or monitors. Thanks again! ;)

[Jeanny]

I think I finally found the issue with my eyes. My gaming monitor had pwm and that's when my eyes started to become more red, dry, and more fatigued is when I got the monitor. Turns out my phone also uses pwm. Do you know if my eyes will heal if I stop using screens with pwm? And if I set my phone to full brightness with dark mode on, with that help decrease on how much the pwm will affect my eyes? My gaming monitor is already at full brightness but hurts my eyes alot. I am upgrading to a pwm/flicker free monitor. Just wanted to know what would be the best settings to set my phone at. Or even a link to someone/forum to help me out. Thank you.

[Antti]

How would the hertz on a screen affect all this?

I was running my screen at 50 hertz compared to 60.. And felt better watching the screen?

As a epileptic whose epilepsy was diagnosed in a strobe light test, I was thinking for a bit, could my epilepsy be caused by PWM modulation..

But naah.. I had a laptop already back in 2004 (Hp Pavilion ze 4400)..

[Antti]

Still continuing with the previous post..

But then again.. That and the other flat screen at the time had TFT display.. Would that be different to the modern flat screens?

[kadajawi]

Well, yes, however this is also a very much coveted feature with TVs, as in black frame insertion. It's what fixes stuttering motion when the source is 24p, and it is a lot better than creating fake frames to create smooth motion. It's also the reason why plasma TVs are still king when it comes to motion — they just tend to flicker. So having the screen flicker isn't necessarily bad.

[Macdara]

Thanks this is really helpful to know, my eyes are killing me from my old display at home and it was making a really annoying buzzing sound until I turned up the brightness to 100%.

I downloaded a software application to dim the screen a bit.

[Dude]

Thanks a lot for including pwm tests and saving eyes all over the world

[Cristian]

Hello, my question is ..is PWM implemented by the display panel itself (for example LG or AUO) or the display manufacturer (for example HP)?

[eivanov]

For those of you who have Intel graphics cards there is an utility to control the PWM frequency. Tested to work on Lenovo W541 - my monitor is working originally on 220Hz and now runs on 10000Hz. Some people on Lenovo forum report increasing the frequency up to 20000Hz. Unfortunately notebookcheck does not allow posting links for users with low post count and guests like me, but you can google it. The name of the utility is 'github.com/tpurtell/PWM'

[Mochamad Aris Zamroni]

Unfortunately many it desktop people doesnt know about this matter and buys bunch of cheap laptops with harmful pwm spec, just like the laptop i currently use.

[Eltwati]

Great article. Clear explanation with rich knowledge .
Thanks.

[Garfield]

PWM is also an important issue with TVs. I've seen terrible pwm on a modern samsung QLED TV. LG seems to have solved it better. I'm really happy to have finally found a tv where i don't see flickering. Thanks for the article.