PolySciences 3025 series, Instruction Manual

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3025
Figure 23
Adjusting the Aperture Diaphragm
The aperture diaphragm is designed for the adjustment of the numerical aperture, not for brightness.
Generally, reducing the diaphragm opening to 70-80% of the N.A. value of the respective objective
will provide an image of acceptable quality. If you want to observe the image of the aperture
diaphragm, remove one eyepiece and look through the tube. You will see a dark circle encroaching on
the bottom of the tube
Swing Out Condenser
Aperture Diaphragm
Figure 21
Figure 22
4-7 Focusing (Figures 21 & 22)
Push the light path selector lever (Figure 25) completely in.
Lower the mechanical stage. With the 10x objective in
position, raise the mechanical stage slowly using the coarse
focusing knob until the specimen is in focus. Then rotate
the fine focus until a sharp image is obtained. Do not allow
the objective to touch the specimen.
4 44 4- -- -8 88 8
Adjusting the Swing Out Condenser
(Figure 23)
The center of the condenser and the light axis of the
objective are coaxial. They have been factory adjusted
and does not need to be adjusted . The upper limit of
the condenser has also been adjusted.
Turn the condenser focus knob to adjust the
condenser. Raise the condenser when using the
higher magnification objectives, and lower the
condenser when using lower magnification
objectives.
Swing out the condenser and away from the
light path when using the 4x objective. Swing
in the condenser and into the light path when
using the 10x and higher magnification
objectives.
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