Motic 1100100401483, Инструкция по эксплуатации

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4.8. Use Of Aperture Diaphragm
• The condenser aperture diaphragm is provided for adjusting
the numerical aperture (N.A.) of the illuminating system of the
microscope, it decides the resolution of the image, contrast,
depth of focus and brightness.
• Stopping down will lower the resolution and brightness but
increase the contrast and depth of focus.
• An image with appropriate contrast can be obtained with an
aperture setting that is 2/3 of the objective N.A.
• To adjust the aperture diaphragm:
- adjust the condenser aperture diaphragm ring referring to the
condenser aperture scale, or
- by observing the diaphragm image visible on the exit pupil
inside the eyepiece tube, or
- by using a centering telescope after removing one of the eye-
pieces and focusing on the aperture diaphragm.
4.9. Use of field diaphragm
• The field diaphragm determines the illuminated area on the
specimen. Rotating the field diaphragm ring changes the size of
the field diaphragm. For normal observation, the diaphragm is
set slightly larger than the field of view. If a larger than required
area is illuminated, extraneous light will enter the field of view.
This will create a flare in the image and lower the contrast.
• The thickness of the glass slide must be 1.7mm or less, otherwise
the field diaphragm may not be focused on the specimen plane.
• The diaphragm does not have any effect when the condenser
top lens is swung out of the optical path in the Swing-out type
condenser. Fully open the field diaphragm, as the N.A. of the
illuminating system will be reduced if the diaphragm is exces-
sively stopped down.
4.10. Brightness and contrast adjustment
• Neutral density filters are used for brightness adjustment in
routine microscopy and photomicrography.
• Green interference (546nm) for phase contrast and contrast
adjustment with black and white film.
• HE (didymium filter) for colour photomicrography of the
Haematoxylin & Eosin (HE) or Fuchsin stained specimen with
tungsten type film.
4.5. Interpupillary Distance Adjustment
• Before adjusting the interpupillary distance, bring a specimen
into focus using the 10x objective.
• Adjust the interpupillary distance so that both the right and
left field of view become one.
• This adjustment will enable the user to observe the specimen
with both eyes
4.6. Diopter Adjustment
• Diopter adjustment compensates for the differences in vision
between the left and right eyes. In addition to making observa-
tion through both eyes easier, this adjustment also reduces the
extent to which focusing is lost when the objective magnifica-
tion is changed. In particular, this occurs when a low magnifi-
cation objective is used.
• Before adjusting the diopter, bring a specimen into focus us-
ing the 10x objective.
• Turn the diopter compensation ring on each eyepiece until
the adjustment ring is adjusted to the “0” position. Position
the 40x objective into the optical path and bring the specimen
image into focus by turning the coarse and fine focus knobs.
• Position either the 4x or 10x objective into the optical path.
Without adjusting the fine and coarse focus knobs, turn the
diopter rings on the eyepieces so that the specimen images in
the left and right eyepieces are focused individually.
• Repeat the above step twice.
4.7. Centering the condenser
• Fully open the field of view diaphragm and condenser aper-
ture diaphragm.
• Set the specimen on the stage with the cover glass facing up.
• Bring the specimen image into focus, using the 10X objective.
• Close the field of view diaphragm to its minimum setting by
means of the field diaphragm ring.
• Turn the condenser focus knob to bring the field diaphragm
image into focus on the specimen plane.
• Adjust the condenser centering screws so that the image of
the field diaphragm appears at the centre of the field of view.
At this time, stopping the field diaphragm image, just short of
the maximum field of view, may be convenient for centering.
• Adjust and centre the field diaphragm so that it is just out-
side the field of view for each magnification change.