A concept of improving a resolution by using human's visual characteristics is provided. An image can be displayed at a more improved resolution than an actual physical resolution, thereby obtaining the same effect that the resolution is physically improved. An image signal corresponding to one frame is split into a first image signal and a second image signal, and a first image and a second image are formed based on the first image signal and the second image signal. Then, the first image and the second image are respectively displayed at a first location and a second location. As a result, a viewer can view the image at an improved resolution.