Augmented reality y (AR) is the term for a constellation of digital technologies that enable users to display and interact with digital information integrated into their immediate physical environment. AR is the technological counterpart of virtual reality (VR), which until recently was much better known, though not necessarily widely used (see virtual realit y). In the late 1960s and early 1970s, the digital graphics pioneer Ivan Sutherland developed the first head-worn computer displays permitting the user to see computer graphics overlaid on their visual field. fi Although Sutherland’s displays constituted the beginning of both AR and VR, interest in VR eclipsed that of AR in the following decades, as display and tracking technologies were being developed. Work on AR was revived in the 1990s by Steve Feiner, together with his graduate students Blair MacIntyre and Doree Seligmann at Columbia University, as well as at other universities and research centers. (The term augmented reality y itself was possibly coined in 1990 by a researcher at the Boeing Company.) AR and VR are often classed as examples of mixed reality (MR) on a spectrum described by Paul Milgram in 1994.
The spectrum indicates the ratio between the amount of information provided by the computer and the amount coming from the user’s visual surround. At one extreme there is no computer input (only the socalled real environment); at the other, the computer is providing all the visual information, and possibly sound as well, to constitute a complete “virtual environment” or “virtual reality.” AR lies in between these extremes, but typically far more of the user’s view is constituted by the actual visual environment and the computer is adding relatively little information. “Augmented virtuality” is a little-used term to describe the case where some elements of the physical world are integrated into a predominantly virtual environment.
The spectrum, however, obscures a fundamental distinction between AR and VR. VR cuts the user off ff from involvement in the physical and, by implication, the social world. AR acknowledges the physical world rather than eliding it. It is one of a trio of such technologies that came to prominence in the 1990s—the other two were ubiquitous computing and tangible computing. Each of these was in its own way a response to the implicit promise of VR to project the user into a disembodied cyberspace (see cyberspace, virtual bodies).
(Johns Hopkins University Press)