Okay... LG 39NZ43RB. Yes, that helps... thanks.
Your TV's convergence circuit has definitely failed. This is probably the most common issue with TVs of this type and age.
You see, your TV has 3 guns that project their colors (red, green, and blue) onto a mirror… which reflects the image onto the display. The convergence circuit pushes and pulls the colors into alignment so they “converge” at the same point. If the circuit fails, the colors separate… and the picture sometimes warps or bows at the edges.
The circuit is made up of a couple integrated circuits called “convergence amplifiers” (pictured below) as well as some resistors and pico fuses. All of these components are replaceable, if you’re good with a soldering iron. A DIY (do-it-yourself) project will run you $30-$60… a technician, $250-$350.
If you want to DIY, I’d check with these guys first. They have repair "kits" available so you won't have to piece together the individual components. Plus, their kits come with picture-based directions and free phone support. For $30-$60 (depending on your model)… that's a good deal. I suggest calling them... a lot of their kits aren't posted on the site.
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