(Object) It is possible to make a display area less perceivable to a user. (Means of Achieving the Object) An HUD device (i.e., the HUD device of the practical example 1) is a display device for displaying in a display area a virtual image of at least a part of a sign that moves. The display device includes a displaying system configured to form an image of the sign that moves with light in a region including an image region (i.e., a predetermined region), and to irradiate a front windshield (i.e., transparent/reflective member) with light that forms at least a part of the image, the part of which is in the image region, such that the virtual image of the at least a part of the image is displayed in the display area. The displaying system includes an FPGA 600 (i.e., control device) that is capable of controlling a characteristic of the image in accordance with position of the virtual image relative to the display area.