Don't know about a Tablet? But if this was a Laptop, I would say either the plug to the screen had come loose, or the screen controller is faulty and needs replacing, or the screen itself is the problem.....Whichever one of those it (Probably) is, you are not going to be able to fix it yourself, so I suggest you send it back to Samsung (if still under guarantee), or find a reputable repair shop that is willing to fix it!