To provide a holographic display device without blur by chromatic aberration even by using fluorescent display tube by providing a fluorescent display tube to an information display source and using specific phosphor for this fluorescent display tube.

Light 3 containing information from an information display source provided with a fluorescent display tube 21 is diffracted by a combiner 20 comprised of a substrate with a hologram formed thereon and visually recognized by an observer 1 as a virtual display image 10. Here, as phosphor of the fluorescent display tube 21, ZnGa2O4:Mn is used. Contrasted with a 100nm or longer half-value width of an emission spectrum of a phosphor ZnO:Zn which is generally used, ZnGa204:Mn phosphor has an about 25nm of a half-value width of the emission spectrum, therefore, generation of chromatic aberration is reduced to a quarter or less than that of conventional one, and a sufficiently permissible display image is obtained. As a display pattern, phosphor may be patterned and arranged in a segment form, but a dot matrix type is more desirable because it can display a higher degree of information.