| dc.description.abstract | In this study, we discuss how to use a two-step holographic process to create a 360-degree viewable conical-type holographic stereogram, which can generate real achromatic image for viewing.
In the first step, we elongate the converging point of the object wave to a silt, which is along to the achromatic angle, by a two dimensional diffuser, and then we record this object wave as the master hologram. In the second step, when reconstructing the information stored in master hologram, the master hologram is divided into two parts, belonging to blue image information and red image information. In order to produce achromatic image, we need to control relative exposure energy for two parts of master hologram, their width, and wavelength pair to change relative diffraction efficiency of these two partial holograms. Finally, when we reconstruct the final hologram using white light from point source, it diffracts light of different wavelengths to the overlapping area, which then achieves achromatic effect for the observed image.
Using the theory of diffraction to simulate experimental viewing system can find that the wave vector of the image wave minus an integral number of the normal vector of hologram is equal the grating vector plus the wave vector of the reconstruction wave. And then use the theory to revise the wave vector of the image wave. The important part of this study is to create a floating achromatic image for conical hologram. So, finally we deform the original 2D images advance and let the width of the silt shrink to 0.15cm to record the master hologram. By viewing the final hologram at paper, larger distance, we are able to observe on achromatic, none deformed real image. | en_US |