Virtual reality
Around the same time, Douglas Engelbart used computer screens both as input and output devices. In 1968, Ivan Sutherland, with the help of many students including Bob Sproull, created what was widely considered to be the first head-mounted display (HMD) system for use in immersive simulation applications. It was primitive both in terms of user interface and realism, and the HMD to be worn by the user was so heavy that it had to be suspended from the ceiling. The graphics comprising the virtual environment were simple wire-frame model rooms. The formidable appearance of the device inspired its name, The Sword of Damocles.
Liquid Image
In 1997 the MRG6 monocular system, priced at $3495, was launched to focus on the wearable computing market. Development of personal wearable systems like those demonstrated by Dr. Steve Mann had demonstrated that practical systems could be developed. The MRG6 was one of the first commercially available wearable computing displays that has since taken over 16 years to finally move to the multiple examples of sunglass-sized devices including the Google Glass. The next monocle, the award-winning M1, was released in the fall of 1997.
By 1997 the demand for VR game systems had almost stopped and the company had not shifted sufficiently to sustainable revenue from sales of wearable computing devices. The original company was sold and was rebranded "TekGear" becoming mostly a reseller of other virtual reality and wearable computing technology. Both David Collette and Shannon O'Brien had left Liquid Image prior to the transition to "TekGear" while Tony Havelka continued to manage and grow TekGear.
A 1997 book, "Training's Future?: Perspectives on Virtual Reality and Related Emerging Technologies (Defense Research Series)" by Robert Siedel describes the system developed by the Royal Canadian Navy to train naval officers on how to be the officer on watch for ships at sea.