This paper introduces a new method to save energy of computer display. Unlike existing power management schemes, which link the display operation to a key press or movement of the mouse, we employ a video camera to bind the display power state to the actual user?s attention. The proposed method keeps display active only if its user looks at the screen. When the user detracts his/her attention from the screen, the method dims the display down or even switches it off to save energy. Experiments show that the method can reduce the display energy significantly in environments which frequently detract the display viewer.