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#11
Thank you @pichlo, your explanation might be correct!

I am aware of the 1st fact you describe, I too played with watch LCD displays and batteries when I was a kid and remember that the number segments only blackened for a moment when DC voltage was applied over the electrodes.

However I never came across the 2nd phenomenon that you describe, that there was permanent change in the display when the charge was left on longer. That indeed seems to be what's happening here.
 

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#12
Originally Posted by juiceme View Post
Any idea what's the root cause and physical phenomenon that this is based on?

From the description I understand that it is nothing like "burn-in" of old CRT's or plasma tubes which results from the same intensity of light being constantly exited off the luminence material which leads to physical wearing-out of the said material.

Also same kind of phenomenon might be possible on OLED displays where bright pixels are worn out, maybe via electomigration of the materials? However this also happens only when the same image is burned to the display for a long time...

But LCD's are a different thing, the colour change in pixels is achieved via polarization change of the material, and in these descriptions the image did not "burn-in" when the same image was shown for a long time but somehow instantly when the device rebooted spontaniously?
And is it so that the image was visible also when the device was turned off?
for me it looks like video memory/framebuffer corruprion
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#13
Originally Posted by coderus View Post
for me it looks like video memory/framebuffer corruprion
Might look so, but then it would be cleared when the device is switched to POWER-OFF, hmm?
 

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#14
Originally Posted by juiceme View Post
Might look so, but then it would be cleared when the device is switched to POWER-OFF, hmm?
well, probably, but mobile devices are powered always and who knows maybe video ram is also powered somehow while switched off
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#15
Originally Posted by coderus View Post
well, probably, but mobile devices are powered always and who knows maybe video ram is also powered somehow while switched off
That's the thought I had when I tried to drain the power as much as possible – perhaps I just wasn't able to do drain it enough.

Quick update:
I've noticed the device is now freezing more often than before. Thrice in the last 24 hours, mostly when idling with display on, showing display glitches. But this could be random, as well. After rebooting swiftly, there are no new visible artifacts.
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