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

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Humphrey Field Analyzer II - i Adjustment / Calibration
Confidential and Proprietary
52235C1105 4 - 35
Field Service Guide
Special Tools/Equipment Required
P
Tool Stand
P
Fake Eye
Prerequisites
Before performing IR LED intensity, check/adjust the following:
1) Trial Lens Holder Alignment (4.9.6)
2) Camera Focus (4.9.7)
3) Bowl IR LED/Mirror (4.9.8)
4) Perform the Camera Position/Size Calibration as previously described in this
service bulletin.
Procedure
Models 720 i
1) From the Calibration main menu, select CAMERA INTENSITY .
2) Set GAIN WITH LENS HOLDER to 35, and STORE it.
3) Set GAIN WITHOUT LENS HOLDER to 35,
STORE
it, and select
DONE
.
Models 740 i and 750 i
1) Dim the room lights and turn down the brightness on the CRT. (This greatly improves
your ability to distinguish small differences in illumination in the CRT image.)
2) From the Calibration main menu, select, CAMERA, INTENSITY .
3) Install the fake eye on the tool stand, and slide the tool stand onto the instrument
chinrest. Push the tool stand forward slightly on the chinrest so that the metal tips on
the Tool Stand Alignment Adaptor make contact with the headrest (Figure. 4-10). This
is the position the tool stand should be in when performing the procedure.
4) Raise and position the trial lens holder against the right angle bracket of the fake eye.
The right-angle extension on the fake eye assembly will press against the trial lens
holder and position it correctly (Figure 4-11). (Set the chinrest height so that the right-
angle extension touches the trial lens holder at about the 0 - 0 level on the trial lens
holder scale.) Verify that there is a central reflex indicating that the reflex LED in on.
NOTE: Once you have the trial lens holder set, do not move it.
5) Center the fake eye to the cross in the video insert.