PURPOSE: To superimpose a pointer mark on an image projected on a screen easily by providing a mirror on which the pointer mark is printed and a means which moves the mirror onto the plane that the mirror occupies.

CONSTITUTION: Reflected light from a liquid crystal panel 302 is guided out by the mirror 306 through a dichroic mirror 304 and a lens 305 and projected on the screen. At this time, an image is already written on the liquid crystal panel 302, so the same image that is written on the liquid crystal panel 302 is displayed on the screen. The other light beam obtained by splitting the parallel light beam through the dichroic mirror 304 is reflected by a pointer mark adding mechanism 303 and superimposed upon the reflected light from the liquid crystal panel 302 by the dichroic mirror 304 and projected on the screen, where the pointer mark printed on the mirror of the pointer mark adding mechanism 303 is displayed.