Coordination: Priv.-Doz. Dr. Gerhard Rinkenauer
Cooperating research groups
"Individual
visual performance", "Modern
human-machine systems"
Head-Up displays (HUDs) are well established in aircraft cockpits. The
situation in road vehicles is different. Some car manufacturers propagate the
use of HUDs to display velocity measurements along with other traffic
information. The expected advantages of this technology include the reduction of
the period of time required to read the display, during this eyes-off-the-road
time, the driver does not attend to the traffic; further, the time needed for
changes in accommodation might also be shortened. On the other hand, distraction
by information not actually needed, or the difference in presentation mode, such
as digital vs. analog, may be disadvantageous.
Published results from eye movement physiology can be used to estimate the
eyes-off-the-road times and to compare them between the HUD and conventional
instrument design. These physiological arguments predict that the reduction in
the eyes-off-the road time at the HUD (versus conventional display) for the task
of reading the velocity instrument is about 100 ms, which is considered marginal
and much smaller than reported in advertisement. Further, no specific additional
time for vergence eye movements seems to play a role at the conventional
display.
Thus, the human vision system seems to be developed ecologically particularly
well to perform fast vergence gaze shift with both eyes from far horizontal
to near declined targets; this condition also applies to the task of reading
the velocity display in the conventional setup. Possible advantages of HUDs
in a car are most likely found in other aspects than the replacement of conventional
instruments.