Objectives - Leica DMil Mode D'emploi

8.2 Objectives

Immersion objectives
• F or immersion objectives use the appropriate
immersion medium.
OIL: only use optical immersion oil
according to DIN/ISO standards
W: Water immersion
IMM: Universal objective for water, glycerol,
oil immersion
Caution!
Follow safety data sheet for immersion oil!
Locking objectives
For some immersion objectives (with knurled
wheel), the objective can be "shortened" (locked).
Then, drops of immersion oil that have not been
wiped off do not accidentally wet objectives and
other specimens when the objective nosepiece
is turned.
• Push the front part approx. 2 mm towards the
nosepiece.
• Lock the objective in place with a small rota-
tional movement.
!
Caution!
When you use the immersion objective again, be
absolutely certain to release the lock, as other-
wise the spring action to protect the specimen
and objective is disabled and, furthermore, the
other objectives are no longer parfocal to the im-
mersion objective.
CORR objectives
These are special objectives that can be adjust-
ed to the thickness of the cover slip.
• By turning the knurled ring, set the corrective
mount roughly to a middle or estimated value.
• Optimize the focus on the specimen.
• Adjust the corrective mount until optimum con-
trast appears; refocus using fine adjustment if
necessary.
The following objectives are particularly well
suited:
• HI PLAN 4x
• N PLAN 5x
• HI PLAN I 10x
• HI PLAN I 20x
• HI PLAN I 40x
And the corresponding phase contrast objectives:
• N PLAN 5x PH0
• HI PLAN I 10x PH1
• HI PLAN I 20x PH1
• HI PLAN I 40x PH1
• HI PLAN I 40x PH2
8. Operation
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