Tracking users through a projection screen

Smart walls, interactive displays, and immersive projection dis are increasingly used in visualization and multimedia system. Tracking the user is one key element to implement inter, or e.g., to render new views according to the viewer's position to creat virtual reality-type displays. Persons viewing traditional screens or virtual reality rooms (CAVE) can be track with elec, optical, or many other tracking methods. If optica or computer vision track is used, then line of sight between the cameras and the tracked object is required. Opaque projection screens severely restrict the possibl camera setup, especially in CAVE-like environments.We present a novel, patented method to track users in three di through a projection screen. Our novel idea is to emplo a screen material that is opaque in the visible spectrum, and trans in the near-infrared (IR) spec, and then to use com vision -based or other optical tracking method to track the viewer in infrared spectrum. Non-solid screens like the FogScree seem to be one screen material that can deliver our objective, but also solid screens may be possible.