Directly viewable stereoscopic projection system

Claim 1

In a stereoscopic viewing system including stereoscopic inputs and an optical display system and wherein said optical display system includes a pair of optical trains, one for each input, and defining therebetween respective intersecting optical axes, a field lens forming a display screen and each optical train further including lens means cooperating with said field lens for focusing a respective stereo image at the intersection of said axes and for forming an exit pupil corresponding to said input respectively at a predetermined focal distance from said field lens such that a viewer situated at that distance from the field lens has his eyes coincident respectively with said exit pupils, the improvement wherein: said stereoscopic inputs comprise separate television cameras, said system includes means for mounting said cameras for movement laterally relative to each other on a base line facing the television camera field of view and for rotating each camera about an axis at right angles to the plane of the convergence point and the base line, for varying the angle of convergence between said intersecting optical axes of said television cameras and for varying the field of view of the television cameras to improve the viewing comfort of the optical display system, said system includes a pair of cathode ray tubes acting as stereo image projectors operatively coupled to said television cameras defining said stereoscopic input and being operatively positioned with respect to said pair of optical trains, said field lens comprising a Fresnel lens facing the viewer and a composite lenticular lens facing said stereo projectors.