An information display device provided with a prism having at least two reflecting
surfaces arranged in facing each other and a hologram surface formed of a reflection-type
hologram. And at least one of the two reflecting surfaces is a light-beam-selective
surface that selectively transmits or reflects light in accordance with its incident
angle. An image light emitted from an image display means enters the prism, and
is reflected between the reflecting surfaces, and then is diffractively reflected
on the hologram surface, and, after being transmitted through the light-beam-selective
surface, is directed to an observer's pupil.
