How is it possible for an OLED screen to have flickering?

[Space Lynx]

I was reading this review here:

ASUS VivoBook 15 OLED K513 (2021) Review

The ASUS VivoBook 15 OLED K513 (2021) is an ultraportable Windows laptop. It's available with various Intel 11th Gen. CPUs, up to 16GB of memory, and over 1TB of...

www.rtings.com

It states one of the issues is flickering (in the negative column, which causes eye strain)... how is this possible in an OLED panel? Each individual pixel turns itself on or off... There is no strobing of a light source...

@R-T-B @nguyen

 

[joemama]

That flickering rate seems to match the refresh rate, there probably was a drop in voltage when every frame was refreshed leading to this

 

[R-T-B]

earlier LG OLED's suffered from a similar thing with gsync. There are firmware workarounds, but yeah, it's basically refresh rate messing with the gamma. Something to do with how each pixel is "charged" during a refresh according to LG, who has finally dealt with the issue AFAIK on the latest panels (but only those).

 

[Nike_486DX]

lol, you probably never read reviews on mobile phones. all oled panes flicker at ~240hz, including samsungs, iphones etc. There is a thing called dc dimming that gets rid of the flicker BUT at the cost of having less accurate colours...

Edit well there is a proof anyways: https://www.notebookcheck.net/Apple-iPhone-12-Smartphone-Review-Apple-phone-with-5G.502437.0.html.
Quote "Because OLEDs don't have background lighting that you could dimm, the entire screen has to be turned on and off all the time to achieve a lower brightness. This causes flickering, which we measured at 226.2 Hz on the iPhone 12. It only stops at maximum brightness"

 

[defaultluser]

CRTs had the same issue; but it was resolved by running the display at a higher refresh rate (usually 85 is good-enough)! Plasmas also suffer from noticeable flicker to many people.

I cant see flicker on my old CRT (but only when running at 85 hz+)
I can't see flicker on my newer LG B7 OLED. Also, several OLED phones also flicker-free to me.

I CAN see flicker on every Plasma I've ever laid eyes on!

You have to be a special kind of freak to be able to see the high refresh of OLEd.

 

[R-T-B]

lol, you probably never read reviews on mobile phones. all oled panes flicker at ~240hz, including samsungs, iphones etc. There is a thing called dc dimming that gets rid of the flicker BUT at the cost of having less accurate colours...

It's a bit more complicated than that. All the LGs are DC dimmed and still suffer from the issue. LG has a writeup on the actual cause for their panels at least somewhere online (I think it may have been in reference to the 9 series), I forget where, but google is probably your friend there.

 

[Space Lynx]

lol, you probably never read reviews on mobile phones. all oled panes flicker at ~240hz, including samsungs, iphones etc. There is a thing called dc dimming that gets rid of the flicker BUT at the cost of having less accurate colours...

Edit well there is a proof anyways: https://www.notebookcheck.net/Apple-iPhone-12-Smartphone-Review-Apple-phone-with-5G.502437.0.html.
Quote "Because OLEDs don't have background lighting that you could dimm, the entire screen has to be turned on and off all the time to achieve a lower brightness. This causes flickering, which we measured at 226.2 Hz on the iPhone 12. It only stops at maximum brightness"

240hz? but phones don't hit that refresh rate, or do you mean anything under 240hz flickers?

 

[defaultluser]

It's a bit more complicated than that. All the LGs are DC dimmed and still suffer from the issue. LG has a writeup on the actual cause for their panels at least somewhere online (I think it may have been in reference to the 9 series), I forget where, but google is probably your friend there.

This is the problem:

LG Promises A Resolution For Latest OLED TV Luminance Overshoot Issue

Affected users may have to wait a while for this one, though

www.forbes.com

Only the hardest of the hardcore video nerds have enough free time to stare at these things from point-blank range at the same image for hours. For MOST of us , we just game or playback videos, or use our HTPC in non-HDR mode (because lowering brightness reduces the chances of early burn-in!)

As a current owner of a B7 65", this wouldn't stop me from buying a CX on clearance - the thin that woulkd stop me is the facyt tha I'm still stuck on a GTX 960 (will buy a 3050 once they drop to MSRP.)

 

[Space Lynx]

This is the problem:

LG Promises A Resolution For Latest OLED TV Luminance Overshoot Issue

Affected users may have to wait a while for this one, though

www.forbes.com

Only the hardest of the hardcore video nerds have enough free time to stare at these things from point-blank range at the same image for hours. For MOST of us , we just game or playback videos, or use our HTPC in non-HDR mode (because lowering brightness reduces the chances of early burn-in!)

As a current owner of a B7 65", this wouldn't stop me from buying a CX on clearance - the thin that woulkd stop me is the facyt tha I'm still stuck on a GTX 960 (will buy a 3050 once they drop to MSRP.)

from reading that article, what I can gather is that modern lets say C1 and the newest C2 OLED should not have this issue, or that it should be so minimized an issue now due to optimizations that is no longer a problem for the latest LG tv's. if that is the case, that answers my question. I simply will wait for laptop and monitors to catch up to LG before I buy any.

in the mean time I think I will go back to my original plan of getting the LG 42" C2 OLED... $1399 is small price to pay for such an insane level of immersion.

 

[eidairaman1]

CRTs had the same issue; but it was resolved by running the display at a higher refresh rate (usually 85 is good-enough)! Plasmas also suffer from noticeable flicker to many people.

I cant see flicker on my old CRT (but only when running at 85 hz+)
I can't see flicker on my newer LG B7 OLED. Also, several OLED phones also flicker-free to me.

I CAN see flicker on every Plasma I've ever laid eyes on!

You have to be a special kind of freak to be able to see the high refresh of OLEd.

75

 

[R-T-B]

This is the problem:

LG Promises A Resolution For Latest OLED TV Luminance Overshoot Issue

Affected users may have to wait a while for this one, though

www.forbes.com

Only the hardest of the hardcore video nerds have enough free time to stare at these things from point-blank range at the same image for hours. For MOST of us , we just game or playback videos, or use our HTPC in non-HDR mode (because lowering brightness reduces the chances of early burn-in!)

As a current owner of a B7 65", this wouldn't stop me from buying a CX on clearance - the thin that woulkd stop me is the facyt tha I'm still stuck on a GTX 960 (will buy a 3050 once they drop to MSRP.)

I dunno. I stopped using gsync on my 9 series because honestly the near black gamma-shift/flicker was pretty awful. I am told newer models handle it better though (plus I like space games, lots of black with contrast there).

 

[Space Lynx]

I dunno. I stopped using gsync on my 9 series because honestly the near black gamma-shift/flicker was pretty awful. I am told newer models handle it better though (plus I like space games, lots of black with contrast there).

I know the new LG C2 42" is not using the new panel type, the C2 48" is though... so I am still waiting... or I need to just suck it up and get the 48"

 

[R-T-B]

I know the new LG C2 42" is not using the new panel type, the C2 48" is though... so I am still waiting... or I need to just suck it up and get the 48"

There are firmware side workarounds the 9 series lacks that newer models get too. The 9 series got the bare minimum effort to "fix" this bug (we basically have a gamma slider).