17
Remove Bertrand lena from the optical path. In the object
field the object image can be seen in phase contrast,
which may be improved by inserting the green filter.
According to the above instructions centre the annular
diaphragms relative to the remaining objectives used. To this
end, displace the individual annular diaphragms indepen
dently of each other. After objectives and annular diaphragm
turrets have been centred once, they can, as a rule, be
used without further centring procedure being necessary.
Rapid change between phase contrast and quasi bright field
is possible:
by completely opening the aperture diaphragm when using
the objectives 20X, 40X, end HI lOOX,
by turning the annular diaphragm turret to symbol
15.Z.
Operation of the small phase contrast
equipment
Insert annular diaphragm into single diaphragm mount ao
that the inscription of the annular diaphragm is pointing
to the objective.
Avoid finger prints.
Insert single diaphragm mount into the reeptive dove
tailed slideway (60) of the condenser support, pushing
it as far as it will go, and clamp it in position by means
of the knurled nut.
Make the following operations in the same
IIIBY
as described
in par. 15.1.
16.
The mount for the condenser support is provided with a set
screw (35) representing a stop for the uppermost position
of the condensers.
Operation:
Select a specimen on an object slide of "standard thick
ness" (e.g. 1.0 mm thickness) and place it on the
microscope stage for observation.
