Analyzer DIK D into the outbreak of the objective change-over switch push (fig. 1/5) in to attack.
Filteraufnahme (fig. 1/12) forward from the Stativfuß take off and to its place the polarizer DIK D postpone; trick cash polarizer in
such a way place that the lever comes to lie between the two lines.
λ
-und
λ
/4-Platte from the path of rays swing out.
Switch on objectively, preparation present, scharfstel len and after Köhler light up. (Finding and focusing with difficulty visible
objects favourably with to a large extent geschlos sener aperture diaphragm. Afterwards again fully open aperture diaphragm).
Bertrandlinse switch on (
►
(5)). Aperture diaphragm with centering screws center (fig. 1/9) to the pupil.
Pin levers in one of the two slots in the ZwischenringDIK D would bring and thus the knurled internal ring so for a long time turn,
to the central, black visibly becoming in the pupil interference fringes in lie horizontally.
Prism guns scolded in such a way that the enlargement of the objective in the window appears. The Interferenzstrei fen must in the
pupil disappear; if number doubles itself its on, the prism lies in the intermediate ring DIK D around 180 in the azimuth
twistedly. Shift back in this case prism gun
○
, prism in the intermediate ring um180° keep turning, until the interference fringe
system appears again horizontal; again prism guns on work objectively scolded, the interference fringes in the pupil
disappeared now.
Bertrandlinse switch off and field observe.
Box spanners on the left and on the right into the centre holes in the prism gun would bring in, into those, which schen opti axle
next lay. Keys turn, until the field appears darkest and no relief-like contrasting to be seen is.
Prism in the intermediate ring DIK D with pin lever slight-adjust, until the field appears darkest. Thus the mechanism is adjusted.
Adjust the contrast: Grey contrast:
λ
/4-Platte swing polarizer turn, until the desired contrast enters.
With the rotation of the polarizer over ± 45° changes the course differentiated
Δ
over ±
λ
/4, thus from a light position over the dark
position (= “quasi-dark field”, no relief effect) for other light position. In many cases the best grey contrast is appropriate for
λ
/8. with
Δ
for instance.
Color contrast: Additionally switch
λ
-plate on, polarizer turn, until the desired color contrast enters.
With the rotation of the polarizer over ± 45 changes the course differentiated
Δ
over
λ
±
λ
/4, i.e. from blue over the “critical color”.
(= sensitive teint), in which the relief effect disappears, to red.
Quasi-light field:
λ
- and
λ
/4-Platte switch and polarizer off up
+ 45° or -45° turn.
Operation of the small mechanisms for differential interference contrast
_________________________________
Intermediate ring DIK D on the objective which can be equipped aufschrau user the allocation comes out from the
imprinted enlargement. (The intermediate rings DIK D 12.5/25 so probably function with GF-PA 12,5x as also with
GF-PA 25x)
Screw combination in intermediate ring objective into the lens turret (with repetitive work with the mechanism notes
one favourably the eye in the lens turret to avoid around adjusting expenditure). If alternatively in differen tiellen
interference contrast and in the phase contrast to be observed is, empty intermediate ring between phase objective,
marked by white ring, and lens turrets screw (alignment length!).
Preparation present, focus and after Köhler light up. (Finding and focusing with difficulty visible objects
to a large extent closed aperture diaphragm. Afterwards again fully open aperture diaphragm.)
Filteraufnahme (fig. 1/12) from stand forward take off and by the polarizer DIK D replace. Swivelling polarizer in such
a way place that the lever comes to lie between the two white lines.
λ
-
and
λ
/4-Platte from the path of rays swing
out.
