Technical description
Due to basic physical principles and the physio-
logy of the human eye, all imaging techniques,
not only the microscope, are subject to limi-
tations in performance. For proper use of the
microscope you should therefore know and
observe the following information.
Performance data of objectives
The Leica DM IL microscope is based on a tube
length of ∞ (infinite) and a focal length of the
tube lens of f = 200 mm.
!
Attention:
For this reason, only objectives with the
engraving ∞ and M 25 thread may be used.
∞
0.17
0
D (or A, B, C)
Objective labelling
Examples and meaning of the symbols:
∞ / –
C PLAN 10x/0.22
∞ / 0.17
C PLAN 40x/0.65
∞ / 0 / D
N PLAN 50x/0.75
Objective for infinite tube length (∞).
The objective can be used with and without a
coverglass.
The objective may only be used with a cover-
glass of the standard 0.17 mm thickness. Use
without a coverglass or with a coverglass of a
very different thickness will result in a distinct
drop in performance, especially for objectives
with high apertures (see below).
Use without coverglass, e. g. for cell smear
specimens, incident light. Not suitable for inver-
se microscopes.
Pupil position of the objective (important e.g. for
Integrated Modulation Contrast IMC).
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