Information reduction in hologram and a 3D display with a movable light source

The superimposing method is described in order to reduce information in hologram. This method improves loss of resolution and increase of the speckle noise which are caused by the information reduction in the sampling method. Experiments are carried out for reconstruction of images from the computer-generated hologram or from the practical hologram. Results show that high-resolution images with low speckle noise are reconstructed from the continuous periodic hologram with reduced information. The image without visual depth is reconstructed on the Fourier transform plane from the hologram with reduced information, if the bandwidth is taken to be smaller than the diameter of observer's pupil. The visual field is divided into several fields in order to display images with visual depth, and images in divided fields are recorded on several Fourier transform holograms. A time-sharing system with a movable reference light source is developed in order to reconstruct real-time 3D images from several Fourier transform holograms with reduced information.