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 - 23
Field Service Guide
4.8.3.2 Bowl
4.8.3.2.1 White
Purpose
This procedure ensures that the brightness of the background illumination is close to the
optimum 2.92 Ft-L.
Special Tools/Equipment Required
P
Soligor Light Meter Kit
P
Digital Multimeter, Fluke 8060A or equivalent
P
Bowl Shroud
P
Small Flashlight
Procedure
1) Set up the Soligor light meter on the HFA II - i and zero out the meter (Appendix A).
2) Set the light meter to position 3.
3) Position the light meter at a point approximately 2 inches up from the center fixation
hole in the bowl.
4) From the Calibration main menu, select
INTENSITY.
5) Set up the instrument as follows to calculate the foot-lamberts:
a) From the Intensity Menu, select P Factors (See Appendix A.2.19) or selectP1, P2
and P3 enter the P1, P2 and P3 factors from your Soligor Meter. Select
P3B,
P3Y
and
P3F
if your light meter has these factors, otherwise enter the BYP3
factor on your meter for P3B and enter the P3 factor for P3Y and P3F.
b) Select
METER
and enter your light meter serial number.
C
Or you can use the Read P Factor floppy disk for this step.
6) Select
BOWL
, then
WHITE
. Allow the bowl lamps to warm up for at least 3 minutes
before proceeding. Observe the DMM voltage reading for 15 seconds to see if the light
output from the bowl lamps has stabilized.
7) Divide 2.92 by the P3F factor on your light meter (or use P3 if your light meter does
not have a P3F factor).
8) Using the pads on the screen menu, increase or decrease background intensity until
your DMM reads closest to the result of the calculation done above. Try to set the
background intensity as close to 2.92 Ft-L as you can. (It must be between 2.72 – 3.13
Ft-L, otherwise the
after evaluation of the bowl light intensity will not be within toler-
ance.)