Improvement of grayscale representation of the horizontally scanning holographic display

The horizontally scanning holographic display has increased viewing angle and display screen size as compared to conventional holographic displays. Elementary holograms, which are generated by a high-speed SLM and projected by an anamorphic imaging system, are aligned horizontally by a galvano mirror. When the frame rate of the SLM is high, the width of the elementary holograms becomes several times as large as their horizontal display pitch so that several sets of elementary holograms can be displayed. A laser is modulated to illuminate different elementary hologram sets by different laser powers. The grayscale representation of reconstructed images is improved by properly designing the elementary hologram sets and the illumination laser powers.