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Chapter 7: Troubleshooting
68
DynaVox
Frequent need to recalibrate: hard contact lenses
•
Recalibrate as needed. The EyeMax lights may reflect off of the hard contact lenses
instead of the user’s eyes. Hard contact lenses can move around on the user’s eyes,
which will throw off the calibration (this is not an issue with soft contact lenses).
•
Consider increasing the button and font sizes.
•
Ask if the user can stop wearing the hard contact lenses, or switch to soft contact
lenses.
Frequent need to recalibrate: glasses
•
Try positioning the device below the user, and angling it up toward the user’s eyes (see
Proper Mounting Position
on page 18).
•
Make sure that there are no reflections from metallic glasses frames or from the nose
bridge (wire-rim glasses can be problematic). See if the user can switch to different
frames, or use masking tape to cover some of the reflective surfaces.
•
Try tilting and angling the device so that any reflections of the EyeMax lights on the
glasses are as far away from the user’s pupil as possible.
•
Any reflective coatings on the lenses can interfere with proper calibration. See if the user
can switch to different glasses without any coatings.
•
Ask if the user can wear “blended” bifocals (instead of “hard-line” bifocals).
•
Consider increasing the button and font sizes or asking the user to stop wearing the
glasses.
The user is unable to keep his or her body steady during the calibration.
•
See if someone else can perform the calibration on the user’s behalf. If possible, find a
person with facial features (shape of the eyes, distance between the eyes) similar to the
user’s.
•
You may also want to consider purchasing a comfortable head brace that allows for limited
movement, but does not completely lock user’s the head in place. This may help the user
maintain his or her gaze on the Maestro/Vmax touch screen.
The user is unable to follow the calibration targets.
•
Point to each target as it appears (position yourself so that your arm does not obscure the
user’s eyes from the EyeMax camera).
•
Connect a switch to your Maestro/Vmax and select the
Calibrate With Switch
check box
in the
Calibration Settings
menu.
Summary of Contents for EyeMax
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Page 26: ...Chapter 3 Installation Setup 22 DynaVox ...