Three-dimensional visualization without glasses: a large-screen autostereoscopic display

This paper describes our time-multiplexed 3-D display technology, which allows groups of viewers to see full stereo with kineopsis (lookaround capability) without the use of any eye or head gear. We detail the constructions of our latest 50-inch screen prototype, which is brighter and has higher resolution than our 25-inch prototype presented previously. The time-multiplexed concept allows the sequential projection of narrow strips of images into the viewer space and provides realistic movement parallax in a horizontal plane with full autostereoscopic images. The time-multiplexed nature allows for full-screen resolution for each view and shared components for the optical trains. Our latest prototype, configured for entertainment applications, replaces our previous color sequential system with separate red, green and blue CRTs to give a brighter image (up to 120 ft-lamberts) with much better color saturation. A new optical layout uses dichroics and beamsplitters to avoid the need for coatings with sharp cut-off frequencies, and a concave-mirror screen provides better image sharpness. We are also able to provide up two fifteen views in each eyebox without any tube-abutment seams. Electronic performance has been improved to provide capability of 30 frames-per-seconds interlaced at 640 by 480 pixel resolution. Special picture-shape correction circuitry has been added to provide a rectangular image-frame, despite a light path skewed out-of-plane. Our prototype consists of two optical channels, which share the same viewing screen and allow two groups of observers to see completely different 3-D scenes simultaneously. Initially configured as a preproduction prototype for the location-based entertainment marketplace, this layout may have novel applications in the military arena.