Zeiss Axiovert 200, Руководство по эксплуатации

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OPERATION
Carl Zeiss Illumination and contrasting techniques Axiovert 200
3-34 B 40-080 e 03/01
3.3.2.3 Setting of transmitted-light phase
contrast on the Axiovert 200 /
Axiovert 200 M
•
Swing phase contrast objective, e.g. Ph 1, into
the beam path.
•
Switch phase stop with the same description as
the phase contrast objective (e.g. Ph 1) in the
turret of the condenser.
•
To check the centering and congruence of the
bright phase stop (in the condenser) with the
dark phase ring (in the objective), remove one
eyepiece from the tube and replace it with the
centering telescope. Use the correction facility
of the centering telescope to focus on the
phase stop and the phase ring in the objective
exit pupil.
When the phototube is used, the Bertrand lens can
also be switched on for observation of the
objective exit pupil. When the Bertrand lens is
used, the factor 1x must be set on the setting
wheel of the Optovar turret.
•
If congruence is not perfect (3-19/ A ), two SW
1.5 Allen keys (3-18/ 1 ) must be used to
recenter the bright phase stop until complete
congruence with the dark phase ring has been
achieved (3-19/
B ).
•
Finally, remove the centering telescope from
the tube and replace it with an eyepiece, or
switch off the Bertrand lens.
However, centering is normally not required, since the phase stops are centered in the factory.
To enhance the image contrast, an interference wide-band filter, green 32 x 4, can be inserted in the
filter changer. Complete phase contrast is only achieved if the bright phase stop (in the condenser) and
the dark phase ring (in the objective) are exactly congruent in the illumination beam path (3-19/
B ).
☞
Adjustment of the phase rings must be performed for all phase contrast objectives used. When
liquid objects are examined in small vessels, the beam path must be aligned to the center of
the vessel, since liquids on the edge of a vessel have the same effect as lenses and impair the
microscope image.
Fig. 3-18 Centering the phase stop on the
condenser
Fig. 3-19 Centering of phase stop (bright in
condenser) with phase ring (dark in
objective)