Here, it is preferable that the virtual images 46, 46′ are displayed, for example, as being entirely translucent in while or a light color to the extent that at least outline of the own vehicle is recognizable so as to prevent misrecognition and confusion with an actual vehicle for the occupant. According to the above, the lane change of the own vehicle to be performed can be expected by the occupant intuitively and specifically in a visual manner.