Auto-stereoscopic double lens raster display with tracked projectors

The article describes work at the Heinrich Hertz Institute on display screens for spectacle-less stereo viewing and gives a general explanation of stereoscopic image viewing. It paper deals with the design and construction of a double lens raster screen with contrast enhancement and an internal diffusor layer, with construction of a transparency/measuring projector and the development of an X/Z head tracking system to monitor and compensate for movement of the observer's head. Diagrams are presented of double lens display screen systems and the following parameters are tabulated: diffusor, scattering-indicator and line function. The CRT screen cross-sections are shown and polar diagrams of light outburst density are presented. The results of optical measurements are tabulated. This leads to a description of complete stereo projectors, with facilities for compensating for observer movement