Hi  I own a 27" Imac I7 (Late 2009) Model computer.. Recently I have noticed these lines that are appearing on my computer screen, the lines are definitely behind the glass cover and inside the screen itself. If you look at this on an angle its clear to see. The lines have appeared to get worse recently.  Does anybody know what this problem is? Or what may have caused this? There is no way any liquids have gotten into the computer, so that can be ruled...