[link|https://www.ifixit.com/User/4210465/Cecilia+Terrile|Cecilia Terrile|new_window=true] this can be caused by a few things. first heck all your video input sources. Try all of them and see if that makes a difference. HDMI, Component, Coax etc. all use different parts of the main board. If one/some show normal, then you know it is your main board that has failed.
It is usually the T-con board if your TV has "double vision" but that is usually from side to side. Yours appears to be a Vsync issue which can be coming from a bad main board. Last but not least (and usually not fixable by the DIY'er) there are also issues on the LCD driver boards (part of the LCD panel assembly). If you live in a very humid climate, you also need to check the connectors for the ribbon cables and the cables itself, since corrosion can also be part of the problem. So remove the cables, check them very carefully for corrosion or any other debris.
If none of this works, and the issue could be the LCD panel, check something like [https://www.youtube.com/watch?v=UwUeBIcUGBM|this video] where the connection from the T-con board to the LCD panel is actually being altered. If I would change boards I would start with T-con (smaller green board with one ribbon cable on the top and two ribbon cable to the bottom going to the panel) then the main board. Blue board with all the video input connections etc.
This document [document|27909] can help you while working on your TV.