Zeiss humphrey HFA II-i series, Руководство по обслуживанию на месте

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General Information Humphrey Field Analyzer II - i
Confidential and Proprietary
Field Service Guide
1 - 12 52235C1105
Spikes that appear on the Gaze Graph (Figure 1-6) are analyzed as follows:
P
Upward spikes indicate that the patient has lost fixation;
•
a spike that reaches the top horizontal line (or higher) indicates 10 degrees (or
more) off fixation;
• a spike that extends halfway to the top line indicates 5 degrees off fixation.
P
Downward spikes indicate as follows:
•
a short spike downward indicates that the gaze at that time cannot be
determined by the software.
• a long spike downward indicates that the patient blinked at the time fixation was
checked.
The absence of marks on the graph indicates proper fixation.
Possible problems associated with the gaze tracking system are reflections from the trial lens,
fingerprints on the trial lens, an improperly aligned trial lens holder, an improperly calibrated or
aligned Gaze Tracking box, and excessive patient tearing.
FIGURE 1-1. Location of Corneal Reflex Marker
FIGURE 1-2. Corneal Reflex marker Location Digitized and Stored in Memory