bidirectional interaction between humans and computers

A necessary but not requisite characteristic of Virtual Reality (VR) is cause-and-effect interaction between someone and their computer. Human-to-computer interaction may have computer tracking of finger, hand, head, eye and/or body movement and/or speech recognition. Computer-to-human interaction may include multi-dimensional image projections, audio production, and kinesthetic (touch and motion) simulation. For more material, click here HMD/ Headset Comparison .

Human sight sensation spans foveal, parafoveal, and peripheral vision. Foveal vision is the center of one's range of sight and gives the highest picture resolution and focus. Image resolution decreases as one moves from the foveal field to the outer portions of the parafoveal field. In any event, human beings have amazing responsivity to motion, even for their peripheral vision. When computer performance to create three-dimensional pictures in a computer moving world is constrained, Virtual Reality systems can take advantage of this structure in human vision. They can render images with more resolution in the center of vision of the user's cover of vision. Systems like this must also be able to adjust picture resolution rapidly in response to head motion. Related topics at Virtual Tours Tennessee .

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