13
●
Minify the aperture below 60% of the objective’s numerical aperture unless in a special case, for
instance, observating an almost transparent specimen.
●
The
numerical aperture is marked on the objective.
For example, the mark “ 10/0.25 ” means the
magnification is 10×
，
and the numerical aperture is 0.25.
●
If you want to observe the image of the aperture iris diaphragm, remove one eyepiece and look
through the tube. You will see a dark circle encroaching on the bottom of the tube.
3.3.6 Adjusting the Interpupillary
Distance
（
Fig.22
）
The interpupillary distance range:
55mm
～
75mm
。
While looking through the eyepieces,
move both sliders to adjust interpupillary
distance until the left and right fields of
view coincide completely. The value on
the right slider is your interpupillary
distance.
3.3.7 Adjusting the Diopter
（
Fig.23
）
Turn the diopter rings
②
on both eyepieces to
align the number on the rings (which is
corresponding to your interpupillary distance)
with the white dot
③
on both sliders to bring
the specimen into focus.
★
The diopter range of the eyepiece is
±5
diopter.The number aligned to the line
on the viewing head is the diopter in use.
②
Fig.23
③
Fig.22
①
