High-Density Directional Display for Generating Natural Three-Dimensional Images

A high-density directional display can produce natural three-dimensional(3-D) images by projecting a large number of directional images using directional rays. When the angle pitch of the directional rays is 0.2/spl deg//spl sim/0.4/spl deg/, more than two directional rays passing through a point in 3-D space enter the viewer´s eye simultaneously so that the viewer´s eye can focus on that point. No discrepancy appears between the convergence function and the accommodation function so that the display does not induce visual fatigue. Two different system configurations are presented: a projection configuration and a thin configuration. A prototype display based on the projection configuration was constructed. The prototype display displayed 64 directional images with directional rays having a horizontal angle pitch of 0.34/spl deg/. The screen size was 9.2 in. The preliminary experimental results showed that a viewer could focus on 3-D images produced by the prototype display.