OPERATION
ZEISS
Illumination and contrast methods in transmitted light …
Axioscope 5/7/Vario
102
430035-7344-001
03/2018
(4) Conclusions
According to the Michel-Lévy color table
(
Fig. 4-11), the gray-white color which occurs in
the bright position as discussed in the example
above (Fig. 4-10/
1
) corresponds to a path
difference of 150 nm.
After insertion of the
λ
compensator the
surroundings of the artificial fiber which is not
birefringent show a bright red which corresponds
to a path difference of the compensator of 550 nm
(the first order interference color for the path
difference of 550 nm corresponds to 1
λ
).
If the polarization direction of the birefringence
sample to be investigated is parallel to the largest
polarization direction of the compensator
λ
, i.e. in
the NE-SW direction, the path difference of the
sample (i.e. gray-white: 150 nm) and the path
difference of the
λ
compensator (red: 550 nm) add
up. This leads to a change in color of the sample
from gray-white to blue-green (resulting path
difference = 700 nm).
If the polarization direction of the birefringence sample to be investigated is perpendicular to the largest
polarization direction of the
λ
compensator, i.e. in the NW-SE direction, the path difference of the
sample (e.g. gray-white: 150 nm) is subtracted from the path difference of the
λ
compensator (red:
550 nm). This leads to a change in color of the sample from gray-white to orange (resulting path
difference = 400 nm).
NOTE
Michel-Lévy color tables can be ordered under literature catalog no. 42-312.
Fig. 4-11
Diagram of the Michel-Lévy color
tables
