Tobii X1 Light Eye Tracker, Руководство пользователя

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Tobii X1 Light User Manual
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The correct distance can be calculated by
using basic trigonometry (see image to
the left). By assuming that the tracked
area is a half circle and that the diagonal
from the center of the screen or other
stimuli to its top corner constitutes the
radius of that half circle, it is possible to
calculate the distance needed between
the participant and the stimuli using the
following formula:
d =
As an example, a monitor with a diagonal from the centre of 38 cm / 13.8 in. would
mean placing the participant approximately 75 cm / 29.5 in. from the monitor. For
recommended display sizes that can be used with the supplied mounts, please refer
to chapter 7.5 Appendix E: Recommended display sizes on page 47. The eye
tracker should always be placed approximately 65 cm / 25.6 in. from the participant.
4.3.1 Track Box
The Tobii X1 Light Eye Tracker allows for extensive head movement. Once the Tobii
X1 Light Eye Tracker / Computer is properly calibrated and placed in front of the user,
no further adjustments are required.
The Tobii X1 Light Eye Tracker allows for head movements of 44 cm x 32 cm / 17.3
in. x 12.6 in. (Width x Height) at the distance of 65 cm / 25.6 in. from the eye tracker.
Depending on factors such as droopy eyelids, visual aids and other characteristics of
the eye, the optimal distance between the person being tracked and the eye tracker
varies. Typical tracking distance limits are 55 to 80 cm / 21.7 to 31.5 in. from the
center of the eye tracker.
In order to be tracked properly, the person to be eye tracked needs at least one eye in
the track box at all times.
27 °
d
s = Diagonal of the screen or
other stimuli from the bottom
center
d = Distance to screen or
other stimuli
s
s
s
tan(27 º )
Chapter 4 Assembling the Tobii X1 Light Eye Tracker