Leica Microsystems DM2000 Manuel D'utilisation page 114

7. Start-up
• Open the field diaphragm just enough for it to
disappear from the field of view (35d).
Note:
The condenser height adjustment depends on
the thickness of the specimen. It may be ad-
justed for different specimens.
Fig. 35 Köhler Illumination
a Field diaphragm not focused, not centered
b Field diaphragm focused, but not centered
c Field diaphragm focused and centered
Diameter shown here is too small
d Field diameter (light) = Field diameter (view)
(Köhler Illumination)
a
c
Fig. 36 Focusing Telescope
1 Adjustable eye lens
2 Clamping ring for fixing the focus position
36
7.3 Checking Phase Contrast Rings
If your microscope is equipped for the use of
phase contrast, the light rings that fit the objec-
tives are built into the condenser.
The light rings are already centered in the fac-
tory. However, the centering should be
rechecked.
A light ring slide which is inserted into the side
of the condenser is used for condensers without
condenser disks. Centering is not required in
this case.
When swiveling in a suitable objective for
phase contrast, the corresponding light ring
b
must be chosen.
The objective engraving (e.g. PH 1) indicates the
corresponding light ring (e.g. 1).
d
Fig. 37
PH=phase contrast ring, LR=light ring
a Condenser in brightfield (BF) position
b Condenser in phase contrast (PH) position
Light ring (LR) not centered
c Light ring and phase ring centered
1
2
Note:
Note:
Phase Contrast Centering Procedure
a b
PH LR
c