Nikon DIAPHOT 300 - Page 16

Adjust so that the phase plate image is
concentric with the annular diaphragm
image. Note that since any
displacement of the phase plate and
annular images will cause low contrast
to the phase contrast image of the
specimen,the exact coincidence of the
two images is necessary.
• System condenser turret unit
Open the condenser aperture
diaphragm to the full. (The optical
path is blocked if the condenser
aperture diaphragm is narrowed.)
Insert two hexagonal screwdrivers into
the annular diaphragm centering
screws of the module in the optical
path, and rotate the screwdrivers to
center the annular diaphragm.
• ELWD condenser
Unclamp the right-hand and left-hand
turret centering knobs. Rotate the
centering knobs for adjustment.
Through PhL centering, other annular
diaphragms are also centered
automatically.
• SLWD condenser
Bring the PhL annular diaphragm into
the optical path, then rotate the
centering screws for adjustment.
Maintain the field aperture diaphragm
fully opened during observation.
(No centering adjustment is necessary
for the Phi annular diaphragm since
it is fixed.)
Figure 2-19
Figure 2-20
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