A holographic screen for displaying images by diffracting and dispersing an image
beam projected by an image projector comprises a main hologram for diffracting
and dispersing an incident image beam from one of an upward angle and a downward
angle, and a directional dispersion hologram, disposed on an image projector side
of the main hologram, for dispersing and transmitting part of the image beam within
a predetermined angle range centered on a direction of incidence thereof, and directly
transmitting another part of the image beam, thereby providing a holographic screen
that can maintain the brightness and improve the color reproducibility of a displayed image.
