12
●
The tight tension of the coarse focus knob
has already been adjusted before leaving
factory. If loosen (e.g. the stage slip down by
its weight), please screw the intention
adjustment collar
to the right position by
③
the supplied spanner.
3.3.4 Condenser Adjustment
（
Fig.20
）
Turn the condenser focus knob to move the
condenser up and down. Raise the condenser
when using the high magnification objective,
and descend it when using the low
magnification one.
The condenser and the objective are coaxial.
It has been adjusted before leaving factory,
so the user needn’t to adjust them by self (the
distance between the top of the condenser
and the stage should be in the range of
0.03mm~0.4mm.)
The highest position of the condenser has
been adjusted too. It also needn’t any user’s
operation
.
3.3.5 Aperture Iris Diaphragm Adjustment
（
Fig.20,21
）
Turn the aperture iris diaphragm lever
①
to
adjust the aperture iris diaphragm.
Generally, setting the aperture iris
diaphragm to 70- 80% of the N.A. of the
objective in use will provide an image with good
contrast.
●
If the size of the aperture diaphragm
minified, the brightness and the resolution
declined, while the contrast and the depth of
field increased; In other words, if the size
largen, the brightness and the resolution
improved, but the contrast and the depth of
field declined.
●
Generally, setting the size of the condenser
aperture diaphragm at 70%
～
80% of the
numerical aperture, you can obtain a clear
image with enough contrast. If the open of
the aperture diaphragm is too small, the
resolution were very low, so please don’t
Magnification
：
10
×
N.A.
：
0.25
①
Fig.20
Fig.21
Specimen
Image of Aperture Iris Diaphragm
