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1.4.11 Maintaining Eyegaze Accuracy
To maintain accurate Eyegaze operation, the camera must be aimed at the same eye on which the
calibration was performed, and the eye must be in good focus. If the user moves out of focus simply
adjust the screen position until you see the eye image clearly.
The camera angle and focus setting
must not be altered after calibration. Re-adjusting the camera angle or focus prevents the system
from accurately predicting where the user is looking; moving the screen to regain focus does not. As
long as you don’t touch the
camera the user can move away from the Eyegaze Edge and return later to
resume operation.
As long as you can move the
screen to refocus the eye it’s not necessary to recalibrate. If you move
the camera or change the focus the user must recalibrate! If the Eyegaze Edge is not responding
accurately to the user’s eye and it is suspected that the camera focus or angle was inadvertently
changed, recalibrate.
1.4.12 Bringing up the Calibration Program from Other Screens
If the System is in an Eyegaze program, press the “Re-Calibrate” key (F1) on the manual keyboard to
bring up the calibration program
. If the user is in a Grid program he must first exit back to Eyegaze
before you press F1.
1.5 Visually Pushing Keys
Note: In Section 1.4, “you” is understood to be the user.
Eyegaze Edge operations occur by visually “pushing” the keys that are displayed on the various
screens. When you look at a key and keep your gaze there for about 1/2-second, the Eyegaze Edge
responds by taking the action associated with that key.
1.5.1 User Feedback: Locator Dot
In our basic Eyegaze programs there are 2 options for the eye-controlled cursor: “Dot in Key”, which
places the cursor at the user’s gaze point or “Dot in Key Center”. In either case the cursor is a very
small red dot. It should be visible but small enough to not be a distraction.
The type of locator dot is selected in the ECS Settings program under Gaze Selection (page 32)
Dot in Key (At user’s Gaze point)