73
7. Start-up
7.7 Checking Phase Contrast Rings
If your microscope is equipped for phase con-
trast, light rings to match your objectives will be
installed in the condenser.
The light rings are already centered in the fac-
tory. However, the centering should be
rechecked.
Note:
Each objective has its own light ring assigned to
it in the condenser. The test must therefore be
performed for each objective.
Regular phase contrast with phase objectives
When choosing an objective suitable for phase
contrast, the appropriate light ring is selected
automatically when using a motorized con-
denser. Otherwise, select the light ring manually.
Leica DMI3000B:
•Set the condenser to the bright field position.
PH LR
Fig. 95 Phase contrast centering procedure
PH=phase contrast ring, LR=light ring
aCondenser in bright field (BF) position
bCondenser in phase contrast (PH) position
Light ring (LR) not centered
cLight ring and phase ring centered
ab c
Fig. 93 Focusing telescope
1Adjustable eyelens
2Clamping ring for fixing the focus position
1
2
Leica DMI4000B and Leica DMI6000B:
•Press the BF (bright field) button (one of the
variable function buttons on the stand).
•Instead of an eyepiece, place a focusing tel-
escope (Fig. 93) in the observation tube or ac-
tivate the Bertrand lens (pull rod (94.1) on
tube).
•Select the phase contrast objective with the
lowest magnification.
Fig. 94
1Activating the Bertrand lens
2Focusing the Bertrand lens
1
2