Olympus BHS-751P Instruction Manual - Page 16

Browse online or download pdf Instruction Manual for Microscope Olympus BHS-751P. Olympus BHS-751P 22 pages. Bhs-p series polarizing microscope

Olympus BHS-751P Instruction Manual
1) Aperture iris diaphragm
Adjust the opening of the aperture iris diaphragm ac-
cording to the various conditions such as the numerical
aperture of the objective, image contrast, depth of focus,
70-80%
and flatness of field. Generally i t is often preferable to
30-
20%
stop down the aperture iris diaphragm t o about
70%
or
80%
of the N.A. o f the objective.
After the eyepiece is removed from the observation
tube, if necessary, look through the observation tube
and check the opening of the aperture diaphragm at the
objective pupil.
2) Field iris diaphragm
The field iris diaphragm controls the diameter of the ray bundle impinging on the specimen
surface and thus increases image definition.
Generally, i t is preferable t o slightly increase the diameter of the field iris diaphragm until
it is just outside the field of view.
2. Pre-focusing Lever
This lever
@
is provided to prevent possible
contact between specimen and objective as
well as to simplify coarse focusing. (Fig.
16)
The lever is locked after coarse focus has
been accomplished. This prevents further
upward travel of the stage by means of the
coarse adjustment knobs, and automatically
H.
Focus Adjustment
1 . Tension of Coarse Adjustment Knobs
and Fine Adjustment
Although the tension of the coarse adjust-
ment knobs has been already adjusted for
optimum performance by the manufacturer,
i t is possible to personally adjust the tension
o f the coarse adjustment for either heavy or
light movement depending on the operator's
provides a limiting stop if the stage is low-
ered and then raised again. The pre-focusing
lever does not restrict fine focusing.
- .
Fig. 16
preference by rotating the tension adjust-
Fig.
15
ment ring
a.
(Fig. 15)
The ring can be rotated by inserting a screwdriver into one of the holes on the periphery of
the ring. The clockwise rotation (in the direction of the arrow) tightens the coarse adjust-
ment knobs. Do not loosen the ring too much, because the stage may drop or the fine
adjustment knobs may slip.
NOTE: Do not rotate the right and left coarse adjustment knobs in the opposite directions
simultaneously. If the stage drops and the specimen goes out of focus, the tension
adjustment ring is too loose. Tighten the ring.