Diffraction light guide plate

A diffraction light guide plate capable of increasing the area of an output image without increasing the total size thereof and having an advantage that the pupil position of a user is not limited. The diffraction light guide plate comprises first and second diffraction optical elements, wherein the first diffraction optical element is an element capable of receiving light incident onto the first diffraction optical element and outputting the received light toward the second diffraction optical element, and the second diffraction optical element is an element capable of emitting light therefrom out of the incident light from the first diffraction optical element.