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2.2 Learning about the device
During a measurement, the device records a series of images. To attract the attention of the
child during the measurement, the device plays a "warble" sound. The speaker required for
this is located behind the vertical slits on the front side of the device.
The camera lens and the LEDs required for illuminating the images are located behind the
black protective shield with the stylized face. This face is also used as a fixation aid.
Note
:
If a child is not looking at the camera lens in the middle behind the hexagon during
the measurement, this can lead to a cancellation of the measurement or incorrect
measured values of the visual symmetry. Therefore do not use any other external
fixation aids!
Note
:
To prevent the protective shield from becoming dirty, we recommend that you do
not touch it. If the protective shield does become dirty, read chapter 5
"Maintenance, Calibration, Servicing and Warranty" for cleaning instructions.
Speaker
Protective
shield
with face
Camera lens
behind
hexagonal nose
Figure 2: Front view of the device (plusoptiX A12C)