TV has a burn-in image that has moved over time
Sorry if this is the wrong place. I have an LCD TV that got a strange single few inch line of light burn in randomly a few years ago. The thing is, the burn in has....migrated? It's like a good foot and a half lower than where it originally burned in. And it's changed angle. There's a small darker spot where it used to be, even. What's going on? If I give my tv another 10 years will the burn in migrate off screen like it seems to be doing?
Flooded screen with white, looks like this. Top darker spot is where it was at first.
This entry was edited (3 weeks ago)
flatbield
in reply to Flickerby • • •That is an interesting one. LCDs as far as I know do not usually burn in and if it is moving then it is not really that anyway.
I will interested what others come up with?
Edit: Is sharp or gradual. Might be warping of films in the backlight for example if not sharp. Just a thought.
Flickerby
in reply to flatbield • • •flatbield
in reply to Flickerby • • •Flickerby
in reply to flatbield • • •Initial burn in was sharp. Looked like someone took a knife to the screen in one spot essentially. But now it's migrated down the initial spot is just slightly darker than the surroundings, and the burn in is now at a 75⁰ angle as opposed to a flat 90.
Edit I should add it's not very noticable unless the screen is flooded with white, extremely noticeable, or you know that it's there.
flatbield
in reply to Flickerby • • •Sounds to me like the backlight behind the LCD. They have components which could potentially sag, stick, or warp. White screen is probably best way to see. Also look at various angles. May be more visible at some angles then others.
Hard to unsee. I know this feeling. I used to work in the industry years ago. Displays are never perfect and hard to unsee things once you see them especially when it was part of your job.
Flickerby
in reply to flatbield • • •flatbield
in reply to Flickerby • • •Backlight I think. Probably film pack warp / buckle / wetout. Just a guess.
Edit: Worst part looks kind of like a wrinkle.
Flickerby
in reply to flatbield • • •flatbield
in reply to Flickerby • • •There are various designs of backlights. They typically have a stack of loose components in an assembly. By loose I mean not totally fixed but not too free. They have to free float enought that temperature changes do not cause issues. They also have to not stick, warp, or buckle over time. Harder to engineer then you might think.
So consider what might happen if for example the top backlight film might buckle some then stick to the back of the lcd. The film might deform which would change its optical properties. Then later thermal cycling might cause release. It might do same elsewhere.
Not saying this is mechanism, but just example.
Edit: Keep in mind the LCD is glass, and the backlight components are plastic. Very different thermal expansion coefficients. Then add LED or CCFL lighting and you have a big changing heat source. Add on top of that humidity changes too.
Flickerby
in reply to flatbield • • •flatbield
in reply to Flickerby • • •PonyOfWar
in reply to Flickerby • • •Flickerby
in reply to PonyOfWar • • •PonyOfWar
in reply to Flickerby • • •cecilkorik
in reply to Flickerby • • •It's definitely not burn-in, it's likely some kind of defect in the backlighting system. For most LCDs the "backlight" is essentially a big thin white/mirrored panel reflecting or diffusing light in a very carefully consistent way from a very bright light source, typically either a fluorescent tube at the bottom or more commonly nowadays evenly spaced strips of LEDs. Some higher end models use more elaborate designs but they're the minority. Defects in the backlight panel, the back of the LCD panel, or stuff like dust or even insects getting inside that reflective/diffuser chamber will affect the consistency of the backlight as it both blocks a bit of the light from reaching some places and reflects it to other places it shouldn't be. That's what it looks like is happening here. It could be some kind of delamination of some of the surfaces inside the TV, or it could be some puff of dust that somehow got inside, or even something like a spider decided that was a great place for a cobweb. Without opening the panel it's hard to say what's going on exactly, it might just need a very d
... Show more...It's definitely not burn-in, it's likely some kind of defect in the backlighting system. For most LCDs the "backlight" is essentially a big thin white/mirrored panel reflecting or diffusing light in a very carefully consistent way from a very bright light source, typically either a fluorescent tube at the bottom or more commonly nowadays evenly spaced strips of LEDs. Some higher end models use more elaborate designs but they're the minority. Defects in the backlight panel, the back of the LCD panel, or stuff like dust or even insects getting inside that reflective/diffuser chamber will affect the consistency of the backlight as it both blocks a bit of the light from reaching some places and reflects it to other places it shouldn't be. That's what it looks like is happening here. It could be some kind of delamination of some of the surfaces inside the TV, or it could be some puff of dust that somehow got inside, or even something like a spider decided that was a great place for a cobweb. Without opening the panel it's hard to say what's going on exactly, it might just need a very delicate cleaning or it might need replacement parts.
If you're afraid of spiders, I'm sorry, you just have to burn the house down now, it's the only way to be sure.
Flickerby
in reply to cecilkorik • • •SharkAttak
in reply to Flickerby • • •