Abstract: Disclosed is a display device adapting a resolution improvement device capable of effectively improving a resolution in a projecting display device and a method thereof. A display device according to the present invention comprises: a light source; an image forming means for forming an image using a light emitted from the light source and an input image signal; a projection means for projecting an image formed in the image forming means on a screen; a displacement means for displacing an image displayed on the screen to be displaced; a driving means for driving the displacement to be moved; and an input signal applying means for applying an input signal to the driving means for the displacement means to be rotated in a predetermined direction. According to the present invention, different images are displayed on a screen periodically. It seems that the greater number of pixels is used than the real number in a sense of sight.