toshiba equium
 

my dad has the above laptop and there is problem with the screen. there is a bar on the right hand side of the screen almost 2 inches in width and the full height of the screen which makes everything on that part of the screen lighter than the rest.
as its his laptop i have no idea whether hes been messing with it although i dont think he has because it is the same when windows is loading. could anyone give me an idea what the problem could be?