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MT-40 Series
3-6
Adjust the Field Diaphragm (Iris
Diaphragm Koehler Illuminator Condenser
Optional)
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.
3-7
Adjust the Aperture Diaphragm
1
.
The aperture diaphragm decides the
numerical aperture of the illumination. Only
when the N.A. of illumination is matching
with the N.A. of the objective, it can obtain
better resolution and contrast, and also
increase the depth of field.
2. As the contrast is usually low, rotate the
handle to make the arrowhead pointed to
③
the related magnification position on
condenser base , namely, to adjust the N.A.
④
of illumination to 70%-80% of the N.A. of
objective. The eyepiece can be taken off
when it’s necessary to observe from the
tube.
Adjust the ring
③
until see the figure as
shown in Fig. 13, to adjust the proportion
(see Fig. 13&14, is the image of aperture
①
diaphragm, is the edge of objective).
②
Fig. 13
Fig. 14
