Does AMOLED screen really turn off pixels when the colour is black?

[KKVinayKumar]

Does AMOLED screen really turn off pixels when the colour is black?

 

[Maurizio Troso]

Does AMOLED screen really turn off pixels when the colour is black?

Sure. That's the way AMOLED works on phones screen and tvs (see online datasheets and Wiki)
You can see that in dark room putting side by side a switched down e.g. 550 and 650 and turning them on togheter.
You'll see the Microsoft sign and then the Windows logo in a dark light blowing background in 550, but popping out brightly on a completely blacked off screen on 650 (I own one)

 

[KKVinayKumar]

Sure. That's the way AMOLED works on phones screen and tvs (see online datasheets and Wiki)
You can see that in dark room putting side by side a switched down e.g. 550 and 650 and turning them on togheter.
You'll see the Microsoft sign and then the Windows logo in a dark light blowing background in 550, but popping out brightly on a completely blacked off screen on 650 (I own one)

But in my Nokia Lumia 925 I see that there will be slight leak of back light (not as much as normal LCD screen) when everything is black and the room is completely dark. I doubt that whether AMOLED turns off its pixels completely when colour is black.

 

[Maurizio Troso]

But in my Nokia Lumia 925 I see that there will be slight leak of back light (not as much as normal LCD screen) when everything is black and the room is completely dark. I doubt that whether AMOLED turns off its pixels completely when colour is black.

Take a look at a 650, a 950 or a Galaxy. Or a Panasonic OLED tv. You'll be astonished. Oled have no backlight, every pixel makes light by itself when lit, elsewhere it stays completey off.
Your phone is a couple gens old, and maybe screen settings aren't good.
Real oled makes real black, like old plasma screens.

 

[xandros9]

But in my Nokia Lumia 925 I see that there will be slight leak of back light (not as much as normal LCD screen) when everything is black and the room is completely dark. I doubt that whether AMOLED turns off its pixels completely when colour is black.

Take a look at a 650, a 950 or a Galaxy. Or a Panasonic OLED tv. You'll be astonished. Oled have no backlight, every pixel makes light by itself when lit, elsewhere it stays completey off.
Your phone is a couple gens old, and maybe screen settings aren't good.
Real oled makes real black, like old plasma screens.

Black pixels still light up noticeably. I saw it on a Galaxy S II, the Galaxy Alpha, the Lumia 925, the Lumia 820, etc. The contrast is better but still nothing like the completely-off-blacks that reviews billed.

 

[Maurizio Troso]

Black pixels still light up noticeably. I saw it on a Galaxy S II, the Galaxy Alpha, the Lumia 925, the Lumia 820, etc. The contrast is better but still nothing like the completely-off-blacks that reviews billed.

I saw by myself side by side with my 650 and my friends Galaxy S5 and NGM and Nexus with 5" IPS fullHD screen.
The difference is impressive. And I confirm, black is real. You can see at most when reading coloured texts on black background. If you din't see that, guess you can't believe.

 

[Maurizio Troso]

I'll try posting a hoemscreen photo (not screenshot) where navigation keys blow out the black like hardware capacitative keys. That's no line bewtween black background and glass frame on a 650 in dark light.
EDIT: consider most of apps like Cortana uses fading black background, not full dark. The difference bwtween app background and keys background is noticeable

 

[KKVinayKumar]

I'll try posting a hoemscreen photo (not screenshot) where navigation keys blow out the black like hardware capacitative keys. That's no line bewtween black background and glass frame on a 650 in dark light.
EDIT: consider most of apps like Cortana uses fading black background, not full dark. The difference bwtween app background and keys background is noticeable

As xandros9 said "The contrast is better but still nothing like the completely-off-blacks that reviews billed." It is true they are not completely black but their contrast is good, 10x times better than normal LCDs and colours are lively. Colours in AMOLEDs come close to colours of real world.

 

[Maurizio Troso]

As xandros9 said "The contrast is better but still nothing like the completely-off-blacks that reviews billed." It is true they are not completely black but their contrast is good, 10x times better than normal LCDs and colours are lively. Colours in AMOLEDs come close to colours of real world.

Check it out. No line btwn black and frame. During night is more noticeable.

 

[KKVinayKumar]

Check it out. No line btwn black and frame. During night is more noticeable.

Even my Nokia Lumia 925 also does the same. Even I also cannot distinguish where the screen ends and where the frame starts. Try this open paint in your Windows computer and paint it black save it and send it your phone and open that image in your phone when the room is completely dark you'll notice that pixels won't turn off completely they just get dim.

 

[a5cent]

Even my Nokia Lumia 925 also does the same. Even I also cannot distinguish where the screen ends and where the frame starts. Try this open paint in your Windows computer and paint it black save it and send it your phone and open that image in your phone when the room is completely dark you'll notice that pixels won't turn off completely they just get dim.

I'm going to side with Maurizio on this.

If you have any light at all in the room (coming through a window, from a digital alarm clock, whatever), that will be reflected by the glass covering your display. if you have any pixel lit at all, even if it's only the battery icon on the status bar, that too will refract and light up your display, even those pixels that should be black. And yes, if your display was damaged (the air tight sealing broke or it was exposed to water) you can get the display to be brighter than it should be.

However, if a display works as intended and a pixel is turned off, it really will emit no light at all. If you think it does then you're either seeing reflected light (which you'll almost always have some of), or the display is broken. The fact that you're seeing back-light leakage (when there is no back-light), makes me think your display is borked.

 

[Krystianpants]

Black pixels still light up noticeably. I saw it on a Galaxy S II, the Galaxy Alpha, the Lumia 925, the Lumia 820, etc. The contrast is better but still nothing like the completely-off-blacks that reviews billed.

It just means the picture is not pure black. If the person creating the image for example may have a gray tone around the image to create some shadow then you will see it. Sometimes lower resolution screens have more bleed through. Trust me on a 950 XL go to a very very dark room then Use readit with their awesome true dark mode. You will see nothing but the text. you won't even see the phone boundaries. And that's because the case is under the pure black screen. The back may not look premium, but their focus on the screen is amazing. They also have very true color calibration. Samsung is not so great at it they like to sacrifice accuracy for vivid/warm colours. Looks better but not accurate. GSMArena said 950xl is one of the best, definitely not a biased site. Oddly enough the 950XL screen seemed to score better than the 950, even though it's the same res and all.

 

[KKVinayKumar]

The fact that you're seeing back-light leakage (when there is no back-light), makes me think your display is borked

I don't think my display is broken. I guess maybe i'm seeing light leakage from navigation bar. My phone is Nokia Lumia 925.

 

[KKVinayKumar]

It just means the picture is not pure black

What about black image created using MS Paint? Will it be true black?

 

[xandros9]

It just means the picture is not pure black. If the person creating the image for example may have a gray tone around the image to create some shadow then you will see it. Sometimes lower resolution screens have more bleed through. Trust me on a 950 XL go to a very very dark room then Use readit with their awesome true dark mode. You will see nothing but the text. you won't even see the phone boundaries. And that's because the case is under the pure black screen. The back may not look premium, but their focus on the screen is amazing. They also have very true color calibration. Samsung is not so great at it they like to sacrifice accuracy for vivid/warm colours. Looks better but not accurate. GSMArena said 950xl is one of the best, definitely not a biased site. Oddly enough the 950XL screen seemed to score better than the 950, even though it's the same res and all.

Well, these were noticeable phenomena with Glance, Daydream, Ambient Display, which are black not dark grey regardless of the phone.

 

[Ariel Takom]

Tbh, I'm with the OP here. I own a 950, and I can still differentiate where the navigation keys (dark theme, navigation bar is set to NOT follow phone's colour scheme) and the black bezel down there, and this was when I'm using it on my bed right before I sleep, all lights switched off.

But then again, I must say that this is only noticeable AFTER looking closely at it. Otherwise, it would really seem as if the navigation keys blended with the bezel's blackness. Add to the fact that I'm one of those #PCGAMINGMASTERRACE peeps, my eyes are trained to look at details that others would otherwise fail to notice (yes, I'm bragging and exaggerating a bit here )

 

[Matty]

Does AMOLED screen really turn off pixels when the colour is black?

Short Answer: Yes

Long Answer: Yes, only when its true black, if its a dark grey, it will still show.

 

[KKVinayKumar]

Tbh, I'm with the OP here. I own a 950, and I can still differentiate where the navigation keys (dark theme, navigation bar is set to NOT follow phone's colour scheme) and the black bezel down there, and this was when I'm using it on my bed right before I sleep, all lights switched off

I also started noticing it when I was in bed with everything switch off and about to go to sleep and room was entirely dark. That is when this question arised. I started doubting whether AMOLED really turn off pixels when the colour is true black. There will be faint glow even when "battery saver" was on.

 

[KKVinayKumar]

Short Answer: Yes

Long Answer: Yes, only when its true black, if its a dark grey, it will still show.

Then why does it still glow even when glance screen was on and also for a fraction of second when the glance screen turns off and screen switches off or goes to standby?

 

[Krystianpants]

Well, these were noticeable phenomena with Glance, Daydream, Ambient Display, which are black not dark grey regardless of the phone.

Not sure about older units which had different pentile arrangements. But whites need rgb lit up. And depending on the arrangement I could see something like a bit of bleed through happening around the edges of the bright white but that's the only explanation. It could also be something that "auto" does when sensing ambient light. I don't use auto most of the time only if i'm outside.

As far as glance screen goes, I think it may be how it's designed. See by illuminating a certain part of a screen super bright and switching off the oleds, you're dropping the lifetime of those particular oleds due to the voltage draw. So it's possible there are algorithms being used to try to make voltage draw more even amongs oleds. This is less likely to give the perceived "burn-in" view. Burn in just means those oleds are not as powerful anymore because they have been subjected to more voltage over time. It's actually more like "burn-out".