[AiboPet]

Oh yes Nelson. Old TV sets that had Atari 2600 systems connected to them....or used as security monitors will have this burn-in if they were like that for a LONG time or the contrast was really high.

The BEST example of this is to go find an old Pac-Man arcade machine and turn it off. The "maze" on almost every one of 'em are burned in. You just don't usually see it unless the tinted glass isn't covering it, or you are servicing it and put up a blank raster.

This also is the biggest drawback to plasma sets.....super high contrast, and watching material with "bars" either top to bottom (letterbox) or side to side (SD)....WILL start to burn them. I even have a Viewsonic LCD that did the same thing. It's not a "burn" in LCD...it's called "persistance" and has to be exercised out.

MAYBE sunlight COULD do this, but it wouldn't be too obvious unless you did something weird like blocked HALF of the CRT from sun. My only curiosity is if all this HEAT does something to the phosphors...or the mask.

And Dave. That "string or wire with handles" is an old trick for us who play with customizing cars. You use a similar setup to cut through the 3M adhesive that holds something like the "Kia" emblem on your Kia Soul's bonnet. MUCH safer than heat guns and PRYING on paint...even with masking tape. I would imagine you DON'T want to be prying on or jamming tools between the CRT and a glass plate.