  Holographic display can show pictures in the way that looks like the same
with the real world, and is thought as the ultimate display technology. But due
to the complexity of the traditional holographic technique, it can hardly be
applied to commercial display systems. In this paper, the field reconstruction
of holograms (or real-time reconstruction of holograms) method, which is more
practical and better than traditional holographic technique in image quality,
is first proposed for realizing the display of true 3D image at free space. By
combining the advantages of geometrical optics and the wave optics, a true 3D
display is successfully designed. And by designing an interactive image
generation chip, the designed 3D display allows user to interact with the 3D
image in the style that's natural to them.
