HEAD-UP DISPLAY, VEHICLE DISPLAY SYSTEM, AND VEHICLE DISPLAY METHOD

A head-up display (HUD) (42) is provided to a vehicle, and configured to display a prescribed image toward an occupant of the vehicle. The HUD (42) is provided with: an image generation unit (420) that emits light for generating a prescribed image and applies the light to a window shield (18) or a combiner; and a control unit (425) that controls an operation of the image generation unit (420). The control unit (425) controls the image generation unit (420) so as to select the display mode of a virtual image object formed by the prescribed image and viewed by the occupant through the window shield (18) or the combiner, to be either a planar image or a stereoscopic image in accordance with a prescribed condition.