Leica DMI6000B, DMI3000B, DMI4000B manual Start-up Checking Phase Contrast Rings

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 DMI3000 B:

¥ Set the condenser to the bright field position.

Fig. 93 Focusing telescope

1Adjustable eyelens

2Clamping ring for fixing the focus position

1

2

Leica DMI4000 B and Leica DMI6000 B:

¥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

2

1

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

a b c

PHLR

73