Essilor AKR 550, Maintenance Manual

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a) Unnecessary reflection of cornea
If there are too many unnecessary reflections close to or
on the image when switching to the Freeze Image
screen, measurement cannot be taken. There are 2
possible causes of the phenomenon.
① The distance between the examinee and the
measurement unit (working distance) is not
adequate.
→
Align correctly and take a measurement again.
② The light axis is off to the side in the optical ASSY.
→
Need to replace the optical ASSY.
b) Measurement image is cut.
If the image is cut on the Freeze Image screen, the
measurement cannot be taken.
There are 2 possible causes of the phenomenon.
①
When taking the measurement, the examinee blinks.
→
Ask the examinee not to blink when it takes
measurement.
②
Pupil of examinee is small.
→
The pupil should be bigger.
(Darken the brightness of the fixation target or of the room.)
c) Measurement image is blurred.
If the measurement image is blurred on the Freeze
Image screen, the measurement cannot be taken.
In this case, it is possible that the drive unit of the
optical unit is not working normally. Check it by
following 7-4 Troubleshooting.
For both cases, align correctly and take a measurement again.