Leica DM2700 M, Instructions Manual

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9. Contrast Methods
9.1.3 Polarization (RL)
• First, confi gure the brightfi eld basic setting as
described in Item 9.1.1.
• Readjust the polarizer.
Polarizer POL:
The “«” arrow of the convertible round polar-
izer holder must be aligned horizontally.
Insert the polarizer (56.2) to the second click
stop. Insert the analyzer (56.1) and turn it until
the desired contrast has been set.
Polarizer ICR:
Insert the polarizer so that the engraved
λ
points backwards.
Insert the analyzer (56.1) until the second click
stop and adjust the zero position (= opposite
the marks). Rotate the polarizer until isotropic
specimens (mirrors) appear dark.
Fig. 56 Polarization
1 Analyzer
2 Polarizer
Polarizer with revolving
λ
plate:
Adjust the zero position of the analyzer.
Rotate
the
λ
plate until it is approximately in its
mid-position.
Rotate the polarizer until the specimen ap-
pears as dark/high-contrast as possible; rotate
the
λ
plate until the correct color contrast has
been achieved.
9.1.4 Interference Contrast ICR
• First, confi gure the brightfi eld basic setting as
described in Item 9.1.1.
• Rotate a suitable objective (such as the N
PLAN or PLAN FLUOTAR) into place.
• Cross the polarizers exactly as described in
Item 9.1.3.
• Insert the objective prism (Fig. 57, correspond-
ing to the identifying letter on the top line of the
objective engraving, e.g. “D”) above the nose-
piece.
The image contrast is controlled using the set-
screws on the objective prism (57.1) and the
aperture diaphragm (54.1).
Fig. 57 Objective prism with setscrew
1 Objective prism
1
2
1