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the specimen by which the contrast can be optimized. The condenser is factory pre-centered. If
needed the following procedure can be followed to center the condensor.
1.
Move the condenser to the highest position.
2.
Select the 10x objective to the light path and focus the specimen.
3.
Rotate the field diaphragm adjustment ring to put the field diaphragm to the smallest
position.
4.
Rotate the condenser up-down knob, and adjusting the image to be clearest.
5.
Adjusting the center adjustment screw and put the image to the center of the field of view.
6.
Open the field diaphragm gradually. If the image is in the center all the time and inscribed
to the field of view, it shows condenser has been centered correctly.
The field (Köhler) diaphragm
By limiting the diameter of the beam entering the condenser, the field diaphragm can prevent
other light and strengthen the image contrast. When the image is just on the edge of the field of
view, the objective can show the best performance and obtain the clearest image. The diaphragm
is factory pre-centered.
Adjusting the Aperture Diaphragm
1.
The aperture diaphragm is used to select the numerical aperture of the illumination. When
the N.A. of illumination is matching with the N.A. of the objective, the highest possible
resolution, dept of field and contrast are obtained.
2.
When contrast is low, rotate the diaphragm adjustment ring to 70%-80% of the N.A. of
objective this will improve the contrast of the image. The diaphragm is factory pre-
centered.
