Spherical full-parallax light-field display using ball of fly-eye mirror

We present an optical system design for a 3D display that is spherical, full-parallax, and occlusion-capable with a wide viewing zone and no head tracking. The proposed system provides a new approach for the 3D display and thereby addresses limitations of the conventional light-field display structure. Specifically, a spherical full-parallax light-field display is difficult to achieve because it is challenging to curve the conventional structure of the light-field displays. The key elements of the system are a specially designed ball mirror and a high-speed projector. The ball mirror uniaxially rotates and reflects rays from the projector to various angles. The intensities of these rays are controlled by the projector. Rays from a virtual object inside the ball mirror are reconstructed, and the system acts as a light-field display based on the time-division multiplexing method. We implemented this ball mirror by 3D printing and metal plating. The prototype successfully displays a 3D image and the system feasibility is confirmed. Our system is thus suitable for displaying 3D images to many viewers simultaneously and it can be effectively employed as in art or advertisement installation.