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Figure 4-1 Shooting failed
4.1 The image is not clear
Cause:
If the image is not clear, it’s because the measurement distance is too far or
too close.
Solution: We recommend that you place the device about 3 feet away from the
subject. Adjust the distance between the device and the eyes of the subject to ensure
that the eyes of the subject can be seen on the screen. Then, move the device back
and forth until a clear corneal reflection point is obtained and the eyelashes and
eyebrows of the subject can be clearly seen on the screen. When the measurement
distance displayed on the screen is 95-105 cm, you can start measuring.
4.2 The subject does not look at the camera
Cause: When the subject is not facing the device, or looking away from the
camera during the examination.
Solution: Remind the subject to turn their body towards the camera, and look
directly into the lens. Sit up straight, and try not to move or blink during the
examination.
4.3 Glasses are found
Cause: The subject has not taken off the glasses during the examination.
Solution: Ask the subject to remove the frame glasses and restart the
examination.
