Zeiss Axioskop 40, Руководство по эксплуатации

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Axioskop 40 OPERATION
Axioskop 40 FL Illumination and contrast procedures Carl Zeiss
B 40-810 e 12/01 3-33
The path difference results from the superimposition (interference) of the vibration direction of the
specimen and that of compensator
λ
.
The greater path difference occurs if the vibration direction of the specimen with the absolutely or
relatively highest refractive index (n
γ or n γ
') is parallel to the greatest vibration direction of
compensator
λ
. The specimen will then appear greenish-blue, for example.
The smallest path difference occurs if the vibration direction of the specimen with the absolutely or
relatively lowest refractive index (n
α or n α
') is perpendicular to the vibration direction of compensator
λ
.
The specimen will then appear yellow, for example.
(4) Conclusions
The grayish white color first occurring in the bright position in the above example corresponds to a path
difference of 150 nm according to the Michel Lévy color chart (3-27).
The "surroundings" of the artificial fiber, which are not birefringent, appear dark red when
compensator
λ
is inserted, which corresponds to the compensator’s path difference of 550 nm (1
st
order
interference color for the path difference 550 nm, corresponds to 1
λ
).
If the vibration direction of the birefringent specimen to be examined is parallel to the greatest vibration
direction of the compensator
λ
, i.e. in NE-SW direction, the specimen’s path difference (e.g. grayish
white: 150 nm) and the path difference of compensator
λ
(red: 550 nm) add up. This results in a color
change to the specimen from grayish white to greenish blue (resulting path difference = 700 nm).
If the vibration direction of the specimen to be examined is perpendicular to the greatest vibration
direction of compensator
λ
, i.e. in NW-SE direction, the specimen’s path difference (e.g. grayish white:
150 nm) is subtracted from the path difference of compensator
λ
(red: 550 nm). A change in the
interference color of the specimen from grayish white to orange (resulting path difference = 400 nm)
then becomes visible.
☞
Michel Lévy color charts are available under Cat. No. 42-312.