In current display panels, a common pixel design is that a physical pixel is formed by three sub-pixels (a red sub-pixel, a green sub-pixel and a blue sub-pixel) or four sub-pixels (a red sub-pixel, a green sub-pixel, a blue sub-pixel and a white sub-pixel) for displaying, so that a physical resolution is a visual resolution. In practical applications, sometimes the visual resolution may be low, for example, in a process of continuously viewing images; and sometimes a high visual resolution is required, for example, at the time of viewing details of a fine image. Since the visual resolution of the display panel is fixed, requirements on different visual resolutions cannot be met.