Multi-user 3D film on a time-multiplexed side-emission backlight system

The desirable features for a portable 3D display include displaying 2D and 3D images without resolution degradation for multiple users, a 2D/3D switchable functionality, and, in particular, a compact volume. To produce a portable 3D display with these desirable features, we propose here a multi-user 3D film combined with a side-emission backlight system that has a directional-sequential light distribution. According to the simulation and experimental results, the multi-user 3D film successfully uses an inverted trapezoid structure to separate the rays of each light source and increases the number of observers from one to three. Additionally, the specification of the inverted trapezoid structure can be determined via equations for different designated viewing positions of the side observer and for the ratio of light intensities for the central and side observers.