Chapter 7 Assembly of the Devices
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5.
From the results on each objective obtained
in step 4-5), find the objective with the
longest distance to the focal point (the
objective that can be moved to the lowest
position while staying in focus). Then using
that objective as the new reference, raise
the level by installing some washers having
the thickness equal to the difference be-
tween the objective and the focal point to
the nosepiece screw bearing surface for the
other objectives.
Combine four washers of different thickness to
get the required thickness. Because the objec-
tive used as the reference has a 0.02 mm thick
washer in step 2, the adjustment amount is the
total washer thickness minus 0.02 mm. (See
the figure on the right.)
6.
Adjust washers for all objectives other than
the reference objective, and adjust the
parfocal point for each objective as much as
possible.
Adjustment of the parfocal point
Notes on Assembly
When moving the correction collar, the focal position for the objective also moves. Do not touch the correction
collar while it is in use.
Washer thickness -0.02 mm
=adjustment amount
Washer
0.02 mm
