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 - 45
Field Service Guide
4.9.7 Camera Focus
Purpose
This procedure adjusts the camera lens for optimum focus. It is not normally necessary
to refocus the camera unless you have done replacements that affect the camera lens
position (i.e., bowl replacement, fixation LED replacement, camera replacement).
Special Tools/Equipment Required
P
Tool Stand
P
Fake Eye with Camera Focus Target attached
P
RTV
Prerequisites
Before starting Camera Focus, the following must be done:
1) Check/adjust the Trial Lens Holder (Section 4.9.6)
2) Check/adjust the Camera Position/Size (Sections 4.8.6.1 and 4.8.6.2).
Procedure
1) Install the tool stand on the instrument, with fake eye attached and height adaptor
removed. 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
4-2). This is the position the tool stand should be in when performing the
procedure.
2) From the Calibration main menu, select CAMERA , then POSITION .
3) Using the chinrest control switch, align the camera focus target in the video insert.
4) Gently rotate the camera lens manually and observe the focus target for best
resolution obtainable. (You may need to use two fingers on opposite sides of the
lens in order to rotate the lens without binding.)
5) Apply RTV at the point indicated in Figure 4-18 to secure the lens in position.
NOTE: Squeeze the RTV onto a piece of waste paper and allow it to thicken slightly
and become tacky before you apply it to the lens.