Zeiss Axio Scope.A1, Руководство по эксплуатации

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OPERATION
Carl Zeiss Illumination and Contrasting Method Axio Scope.A1
82
M60-2-0007 e 05/08
The phase difference results from the interference of the polarization of the sample and the polarization
of the compensator
λ
.
The larger phase difference occurs when the polarization direction of the sample or the absolute or
relative largest index of refraction (n
γ
or n
γ
') is parallel to the largest polarization direction of the
compensator
λ
. The sample appears then e.g. in blue-green.
The smallest phase difference occurs if the direction of polarization of the sample with the absolute or
relative smallest index of refraction (n
α
or n
α
') is perpendicular to the polarization direction of the
compensator
λ
. The sample then appears e.g. yellow.
(4) Conclusions
The color grey-white which occurs in the bright position as was discussed in the example above,
corresponds according to the Michel-Lévy color table (
656H656H
Fig. 4-9) to a phase difference of 150 nm
The surrounding of the artificial fiber which is not birefringent shows after insurgence of the
compensator
λ
a bright red which corresponds to a phase difference of the compensator of 550 nm (the
interference color 1st order for the phase difference of 550 nm corresponds to 1
λ
).
If the polarization direction of the birefringence sample which is to be investigated is parallel to the
largest polarization direction of the compensator
λ
, i.e. in NE-SW direction, the phase difference of the
sample (i.e. grey-white: 150 nm) and the phase difference of the compensator
λ
(red: 550 nm) add up.
This leads to a change in color of the sample from grey-white to blue-green (resulting phase difference
= 700 nm).
If the polarization direction of the birefringence sample which is to be investigated is perpendicular to the
largest polarization direction of the compensator
λ
, i.e. in NW-SE direction, the phase difference of the
compensator
λ
(red: 550 nm) is subtracted from the phase difference of the sample (e.g. grey-white: 150
nm). This leads to a change in color of the sample from grey-white to orange (resulting phase difference
= 400 nm).
Color tables according to Michel-Lévy can be ordered under ord. no. 42-312.