Zeiss Axioskop 40, Руководство по эксплуатации

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OPERATION Axioskop 40
Carl Zeiss Illumination and contrast procedures Axioskop 40 FL
3-24 B 40-810 e 12/01
3.5.2 Setting transmitted-light phase contrast
(1) General principle
The phase contrast technique is ideal for examining thin, unstained specimens, e.g. culture cells. The
human eye is unable to see phase differences (differences in refractive index and thickness) between the
different cell components.
The phase contrast technique uses the optical modulators "phase stop and phase ring" as well as the
interference procedures during formation of the intermediate image in order to change the small phase
differences into intensity and color differences that are visible to the eye.
The high-intensity, direct light components are attenuated with the optically defined ring channel "phase
stop and phase ring" and given a constant phase shift. The indirect light components diffracted at
different cell components, however, bypass this optical channel and are influenced by the in-phase
refractive index and the thickness differences in the specimen.
In the intermediate image plane, the partial beams subject to different influence interfere and are
enhanced or attenuated - depending on the phase position. This interference results in image contents
displaying distinctions in intensity and color that can be perceived by the human eye.
(2) Axioskop 40 and Axioskop 40 FL configurations
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Phase-contrast objectives with phase rings Ph 1, Ph 2 or Ph 3 for different average numerical
apertures that can also be used in bright field without restriction.
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Universal condenser with turret disk containing centering phase stops Ph 1, Ph 2 and Ph 3 for
different average numerical apertures or
0.9/1.25 H condenser with slider with any combination of a max. 2 phase stops (Ph 1, Ph 2, Ph 3).
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The inserted phase stop on the condenser must match the corresponding label on the objective, e.g.
Ph 1.