Virtual Realities


Main characteristics:

    • Three-dimensional objects and environments
    • Multi-sensory input (visual, auditive, haptic, autosensory)
    • User should feel immersed

I/O devices:

    • "Desktop VR": (touchsensitive) Screen, Mouse (3D) The linked image shows a 3D mouse that can be used to rotate virtual objects in three dimensions
    • "Immersion VR": helmet The linked image shows user with a virtual reality helmet exploring some chemical structure., LCD glassesThe linked image shows a young lady with 3D LCD glasses, or caveThe linked image shows a so-called "cave" where a virtual environment is projected onto a transparent screen from 4 sides and the top
                                 data glove The linked image shows a data glove that registers movements of the fingers The linked image shows a data glove that registers movements of the fingers, location detectors

Main usage

    • Exploration The linked image shows a user exploring a 3D virtual reality model of the human brain. The movie shows several cave-based virtual reality environments for scientific exploration and demonstration The linked movie shows a virtual tour through St. Mary's church in Dresden before reconstruction was started. It is actually a movie and not a VR system, but gives an impression of what a VR system would look like. of 3D objects or environments
    • Training The linked image shows a cockpit simulator
    • Virtual interface The linked image shows a virtual interface for an astronaut who sees this interface through his VR helmet
    • Physical co-presence with others (entertainment, meetings) The linked image shows a virtual meeting rooms where users who are represented by avetars can meet

Immersion improved through:
    • matching input from at least two sensors
    • high refresh rate (forgo photorealistic verisimilitude if needed The linked image shows a wireframe face )
    • small delays after user actions (< 100 msec)
    • at least monoscopic view with motion parallax (but added stereoscopy is better)
    • three-dimensional sound

Problems:
    • many users of immersion VR get headaches, become drowsy, nauseous...
       (due to vection The linked image shows a virtual interface for an astronaut who sees this interface through his VR helmet, lag of visual update??)
    • users loose orientation