The Development of Multi-Depth Pepper´s Ghost Display for Mixed Reality System

Pepper´s ghost is a well known technique in theater productions that allows the appearance of a semi- transparent and perhaps flying ghost on the stage. This technique has also been used with digital display to create a mixed reality (MR) system, where dynamic virtual objects are presented together with the static diorama. The usual pepper´s ghost setup does not allow the presentation of the virtual objects in different z location. This paper describes the development of a pepper´s ghost MR system that is able to display the virtual objects in varying z locations. In this implementation, we used six layers of polymer dispersed liquid crystal (PDLC) as the projection screens. By adjusting the on/off status of the PDLC layer, we were able to present objects at different depths.