The Sword of Damocles is widely misattributed as the name of the first AR (or VR) display prototype. According to Ivan Sutherland, this was merely a joke name for the mechanical system that supported and tracked (using attached wires) the actual HMD below it.[1] It happened to look like a giant overhead cross, hence the joke. Ivan Sutherland's 1968 ground-breaking AR prototype was actually called "the head-mounted display", which is perhaps the first recorded use of the term "HMD", and he preferred "Stereoscopic-Television Apparatus for Individual Use."[2]
This is widely considered to be the first functional augmented reality system, featuring optical transparency. Morton Heilig is widely credited with the first virtual reality stereoscopic head-mounted viewing apparatus (known as "Stereoscopic-Television Apparatus for Individual Use" or "Telesphere Mask") earlier, patented in 1960.[3]
This prototype was created in 1968 by computer scientist Ivan Sutherland with the help of his students Bob Sproull, Quintin Foster, and Danny Cohen. Before he began working toward what he termed "the ultimate display",[4] because it could theoretically simulate any kind of display, including 2D monitors. Ivan Sutherland was already well respected for his accomplishments in computer graphics (see Sketchpad). At MIT's Lincoln Laboratory beginning in 1966, Sutherland and his colleagues performed what are widely believed to be the first experiments with head-mounted displays of different kinds.
Sutherland1
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