<p>A graphic display device is provided with a display section for projecting an optical image, and a prism for leading the optical image projected from the display section to the eyes. The graphic display device is characterized in that it is provided with an imaging distance detecting means for obtaining an actual measurement value or an estimated measuring value of an object distance when the graphic display device is mounted; a target imaging distance setting means for setting a target imaging distance corresponding to the object distance detected by the imaging distance detecting means; and an imaging distance control means for controlling the imaging distance of an image projected on the prism based on the target imaging distance set by the target imaging distance setting means.</p>
