Ryf Axio Lab.A1 Operating Manual page 86

Carl Zeiss
1 Slide 6x20 with /4 plate
2 Lower section of circular polarizer
3 Lever for rotating /4 plate
4 /4 plate in upper part of the circular polarizer
5 Adjustment slits
Fig. 4-9 Components for circular polarization contrast
An (anisotropic) specimen should not be observed until after the above adjustment.
Reinsert the specimen to be examined.
In their interference color – dependent on material, specimen thickness and orientation – the specimens
appear constant and independent of stage rotation.
For a high-contrast image with higher objective enlargements (from approx. 20x) the
illumination aperture must be reduced to a value between 0.15 and 0.20, i.e. the aperture
diaphragm must be closed accordingly.
The effect of the /4 plate (Fig. 4-9/4) can be undone by either swiveling it out of the light path
or turning it with lever (Fig. 4-9/3) into one of its two click-stop positions.
86
OPERATION
Lighting and contrasting method in transmitted light
430037-7144-001
Axio Lab.A1
04/2013