ZEISS
3 Product and Functional Description | 3.4 Microscopy and Contrast Methods
Fig. 35: Schematic diagram of the color charts developed by Michel-Lévy
When the lambda compensator is brought into the beam path, the non-birefringent "surround-
ings" of the synthetic fiber appear dark red, which corresponds to the path difference of the com-
pensator of 550 nm (1st order interference color for the path difference of 550 nm corresponds
to 1 λ).
If the polarization direction (n
γ
or n
γ'
) of the birefringent sample to be examined is parallel to the
principal polarization direction (n
γ
) of the lambda compensator, i.e. in the northeast-southwest di-
rection, the path difference of the sample (e.g. gray-white: 150 nm) and the path difference of
the lambda compensator (red: 550 nm) add up. This results in a color change of the sample from
grayish white to greenish-blue (resulting path difference = 700 nm).
If the polarization direction of the birefringent sample to be examined is perpendicular to the prin-
cipal polarization direction of the lambda compensator, i.e. in the northwest-southeast direction,
the path difference of the sample (e.g. gray-white: 150 nm) is subtracted from the path difference
of the compensator (red: 550 nm). In this case, the interference color of the sample visibly
changes from gray-white to orange (resulting path difference = 400 nm).
Instruction Manual ZEISS Axioscope 5, Axioscope 5/7 MAT | en-US | Rev. 13 | 430035-7344-001
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