An image display device including a receiving section acquiring a synchronizing signal superimposed on a digital signal, an image generating section outputting image data based on a digital signal, a control section controlling the image generating section, an adjusting section making an adjustment to the digital signal based on setting information, and an information inputting section to which a display instruction to display a setting image for assisting the change of the setting information is input, wherein the image generating section generates a second synchronizing signal different from the first synchronizing signal, and the control section controls the image generating section.