research, a breakthrough that provided initial building blocks for a commercial VR infrastructure, the mixture of research projects that led to biomedical applications, the role of entertainment applications in expanding use of VR, and the growing role of military R&D in producing commercial spin-offs. The last section of the chapter summarizes the lessons learned from history.
The earliest use of a computer-generated graphical display on a cathode ray tube (CRT) was in Project Whirlwind, a project sponsored by the U.S. Navy to develop a general-purpose flight simulator (see Chapter 4). By the late 1940s, Robert Everett at the Massachusetts Institute of Technology (MIT) had developed a light gun that could cause the CRT to react. Researchers on SAGE, the successor to Whirlwind, made extensive use of interactive graphics consoles with displays equipped with a light gun capable of sending signals coordinated with the display. By 1955, U.S. Air Force personnel working on SAGE were using light guns for data manipulation.
These and other early projects convinced a number of researchers that the capability to interact with a computer in real time through a graphical representation was a powerful tool for making complex information understandable. In the late 1950s and early 1960s, several government agencies, including the National Science Foundation (NSF), National Institutes of Health (NIH), National Aeronautics and Space Administration (NASA), and various divisions within the Department of Defense (DOD), began funding research to address an array of computer graphics problems, including the development of input/output devices and programming.
The total funding for these early programs was comparatively small. For example, the NSF allocated about 8 percent of its annual computing research budget to computer graphics between 1966 and 1985. Its graphics-related expenditures rose from $93,000 to $1.8 million annually during this period.5 Another source of funding for computer graphics research during these years was the Information Processing Techniques Office (IPTO) of the DOD's Defense Advanced Research Projects Agency (DARPA, known at times as ARPA). The IPTO support for the development of interactive graphics was concentrated at MIT, Carnegie Mellon University, and especially the University of Utah, which received $10 million in IPTO support for interactive graphics research between 1968 and 1975 (Stockham and Newell, 1975; Van Atta et al., 1991a,b). University programs were only loosely coupled to deliverable systems but supported visionary ideas and the training of students to pursue them.