We propose the omnidirectional 3D display system which displays directly touchable 3D images. The display surface of the proposed display is cylindrical, and displayed 3D images are observed around the cylindrical display surface. The proposed system composed of multiple basic display
units. Each basic display unit consists of an LCD and a holographic optical element which works as a microlens array. The display surface of the proposed system is the virtual screen which is composed of multiple light focusing points (3D pixels) equally spaced in a cylindrical shape. Therefore,
the display surface is not the physical obstruction when observers touch 3D images directly. In order to verify the effectiveness of the proposed system, we constructed the 144-degree prototype system. The virtual cylindrical display surface was composed of 8 basic display units. The angle
of view of each 3D pixel which formed the virtual cylindrical display surface was 15°, and each 3D pixel irradiated 6 light rays at 3° intervals. The diameter and the height of the virtual cylindrical display surface were 42.6 mm and 50 mm, respectively. A displayed 3D image was directly
touchable and was observed from 144° directions.