the screen is lighted (backlight) system for you to see it, if it is new, I would return it for another. the component that is lighting (backlight behind the lcd) is looking to be faulty.
I'd be inclined to get it exchanged if you can - - I bought a new Acer monitor yesterday and don't see any uneven lighting on it at all when I fill the screen with a uniform white or any other uniform colour.