True three-dimensional arcade games that don’t need glasses or head-sets will be in arcades in the second half of next year, according to Infinity Multimedia Inc. The Los Angeles company has agreed with the Thomson Multimedia arm of Thomson SA to support development of a new display technology from a British company, Autostereo Systems Ltd, that creates three-dimensional images and enables multiple viewers look around the sides and behind of the objects being displayed. The system uses time multiplexing of images to flash multiple pictures up on a cathode ray tube at high speed, one after the other. While one of the pictures is being displayed, one of a set of liquid crystal shutters is opened, making the picture visible to part of the display. The shutters determine where an observer can see each of the pictures. The shutters switch at a rate of around 60 times a second. So each of the observer’s eyes see a series of very short images of one of the pictures. The eye assimilates these short bursts of picture to give the effect of a continuously displayed image. And since each eye sees a different picture, the observer gets a depth cue – stereo parallax. As the head is moved, another depth cue – movement parallax – is given so that combined, these give the impression that the image has real depth. The first products will be for video arcades and will be in products in the second half of next year. One of the special monitors will cost between $2,000 and $3,000 in the first instance, which compares to $200 to $300 for a current monitor. For a wide field of view display with say 10 views, the specialist picture display must have 10 times the conventional 50Hz television raster to prevent flicker. This high-speed cathode ray tube also needs phosphors with a very fast decay time: these are used in a custom CRT that has been developed by Autostereo Systems of Cambridge, an offshoot of Cambridge University. The custom shutter component is being manufactured by Thorn EMI Plc, although Autoscan said the component has completely separate from three-dimensional television work Thorn’s Central Research Laboratories announced in April (CI No 2,636). The next product will be a computer monitor package consisting of plug-in board and screen. The partners are also working on an applications development environment for games developers and on a way to make standard television programmes three-dimensional ones.