The condition under which high accuracy is assured when using an eye-gaze input system was identified.
It was also investigated how direction of eye movement
affected the performance of an eye-gaze input system. Here,
age, the arrangement of targets (vertical and horizontal),
the size of a target, and the distance between adjacent
rectangles were selected as experimental factors. The
difference of pointing velocity between a mouse and an eyegaze input system was larger for older adults than for
young adults. Thus, an eye-gaze input system was found to
be effective especially for older adults. An eye-gaze input
system might compensate for the declined motor functions
of older adults. The pointing accuracy of an eye-gaze input
system was higher in horizontal arrangement than in
vertical arrangement. The distance between targets of more
than 20 pixels was found to be desirable for both vertical
and horizontal arrangements. For both the vertical and
horizontal arrangements, the target size of more than
40pixels led to higher accuracy and faster pointing time for
both young and older adults. For both age groups, it tended
that the pointing time for the lower direction was longer
than that for other directions