EXAMET-4 SERIES MICROSCOPE
UNITRON
®
73 Mall Drive, Commack, NY 11725 • 631-543-2000 • www.unitronusa.com
17
OPERATION
(continued)
Adjusting the Field Diaphragm
- Reflected Illumination
(Fig. 20-21)
By limiting the amount of light 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 will obtain the clearest image.
Push the field diaphragm adjustment lever
all
the way in to minimize the field diaphragm.
Observe the image through the eyepiece and
adjust the field diaphragm centering lever
until
the image is in the center.
Slowly open the field diaphragm adjustment lever
. When the image in the diaphragm field in
aligned with the field of view, the field diaphragm
is centered.
Adjusting the Aperture Diaphragm
-
Reflected Illumination
(Fig. 22-23)
The aperture size is increased or decreased by
rotating the aperture diaphragm adjustment knob
. When the aperture is closed, the brightness
and resolution are decreased but the contrast and
range of focus are increased. If the aperture
diaphragm is opened, the brightness and
resolution are increased; however, the contrast
and range of focus are diminished.
For optimal viewing conditions set the condenser
aperture diaphragm lever to match the
magnification of the objective in the optical path.
Adjusting the Oblique Illumination
-
Reflected Illumination
(Fig. 24)
When the oblique illumination lever
is pushed
all the way in, the system is in oblique illumination
observation; when pulled all the way out, it is in
normal reflected illumination observation.
To adjust the limit block for various specimen
requirements, loosen the lock screw
on the limit
block
, then move the limit block according to the
direction shown in Fig. 24 and tighten the lock
screw when adjusted to the appropriate position.
Fig. 22
Fig. 23
Fig. 24
