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Benefits offered by the technology
Regardless of the industry or application, the essential benefits of touchscreen techno-
logy remain unchanged.They:
- Enable people to use computers instantly, without any training whatsoever;
- Reduce operator errors significantly. Users make their selections from clearly defined
menus;
- Eliminate keyboards and mice which many users find intimidating and cumbersome;
- Are rugged enough to stand up to harsh environments where keyboards and mice
often get damaged;
- Provide fast access to all types of digital media, with no text-bound interface getting
in the way;
- Facilitate multilingualism in dedicated applications;
- Ensure that no space on the desktop or elsewhere is wasted as the input device is
integrated into the monitor.
Head-mounted displays and Shutterglasses
Head-mounted displays
Head-mounted displays (HMD's) are portable, wearable monitors. Stereoscopic vision
is achieved via the combination of two little LCD or CRT monitors, one for each eye.
In addition, these devices may include a headtracker which either replaces or comple-
ments the use of keyboard, mouse or joystick input by tracking the movements of the
user's head. Stereo-headphones or multiple loudspeakers may be used to create mood or
deliver information.
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HMD's are like a set of heavy sunglasses that a computer can write over.Typical aug-
mented reality (AR) systems overlay transparent or semi-transparent computer graphics
on top of the real world, and constantly align the graphics with the user's view direction
and head position.
The fundamental difference between and VR and AR displays is most noticeable
when they are switched off.With VR the screen is black.When AR is turned off the
viewing glass becomes transparent. AR provides a noticeable contrast between the real
and virtual worlds, and will continue to do so until photorealistic, immersive virtual real-
ity becomes commonplace.The challenge with AR displays is to fix the artificial graphics
in relation to positions in the real world, so that the motion of the user's head does not
make the graphics `swim'.This is done by tracking head motion and transforming the
graphics to compensate. Poorly tracking the motion can induce feelings similar to sea-
sickness. Slow motion analysis and graphics pipeline delays may be compensated for by
estimating the user's motion with a Kalman Filter, which anticipates the user's future
movements based on current movements, and compensates for these accordingly.
HMD's are often classified according to whether they are occluded or see-through
displays. Occluded (or inclusive) displays make visible to the user only the image pro-
duced by the display, while see-through (or augmented vision) displays allow the viewer
to see both the image produced by the display and the surrounding real environment.
HMD's can be classified according to the number of images presented and to which eye-
Human Interfaces
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See the visit to Glasgow School of Art's Digital Design Studio, below, for an account of such a
multi-speaker set-up.