Widening Viewing Angles of Automultiscopic Displays Using Refractive Inserts

Abstract

The viewing position is chosen to be at the boundary of the safe viewing zone of a conventional display (top view). Considerable aberrations are observed (white arrows) in the conventional solution. These errors are not present when refractive inserts are used (rightmost). Our prototype performs spatio-angular multiplexing of a 3840 × 2160 screen to achieve an angular resolution of 36 × 36 and a spatial resolution of approximately 106 × 60 (hence the prominent pixels in the photographs). Please see accompanying video.Abstract-Displays that can portray environments that are perceivable from multiple views are known as multiscopic displays. Some multiscopic displays enable realistic perception of 3D environments without the need for cumbersome mounts or fragile head-tracking algorithms. These automultiscopic displays carefully control the distribution of emitted light over space, direction (angle) and time so that even a static image displayed can encode parallax across viewing directions (lightfield). This allows simultaneous observation by multiple viewers, each perceiving 3D from their own (correct) perspective. Currently, the illusion can only be effectively maintained over a narrow range of viewing angles. In this paper, we propose and analyze a simple solution to widen the range of viewing angles for automultiscopic displays that use parallax barriers. We propose the use of a refractive medium, with a high refractive index, between the display and parallax barriers. The inserted medium warps the exitant lightfield in a way that increases the potential viewing angle. We analyze the consequences of this warp and build a prototype with a 93% increase in the effective viewing angle.