(20) Streckenmessunqen in 2-Richtung (parallel to-optical axle)
With limited requirement at accuracy can such Mes sungen with the Feintrieb to be accomplished. One proceeds thereby as follows:
Measuring object for observation furnish, after Köhler light up; Objectively as high an aperture as possible use (the more largely
the aperture, the smaller the sharpening deep, all the more largely the measuring accuracy).
Object with Feintrieb lower (in the clockwise direction turn Triebknopf), until the upper terminator point the Z-distance which
can be measured appears sharp, this attitude slightly (up to the Unschärfe) over-drive.
Focusing direction turn around (turn Triebknopf against hand sense), until the upper terminator point appears sharp to the Z-
distance. Scale values from the Feintrieb read off = Z1 •
Z2
over drive he to the lower terminator point of the measuring
section seem sharp. Scale values from the Feintrieb read off = Z2.
The distance between Z1 and Z2 must be driven through without reversal of the focusing direction, in order to avoid that the reversal
span of the impulse (
≤
2
μ
m) enters as error measurement.
Repetitions of the measurement in the same, indicated direction would always drive through.
•
Computation of the material distance
Δ
Z:
n
Δ
Z =Z
−
⋅
Z
21
n
′
n = refractive index of the object, usually for instance the Brech number of the medium accordingly, into which the object is
embedded.
n' = refractive index of the medium between Frontlinse of the whether jektivs and cover glass; usually 1 (for air) or 1.515 (for
immersion oil).
(21)
The achromatic condensor lens head 1,3
In consideration of rapid and simple operation one uses rear objectives with apertures favourably > 1 with the condensor lens 0.9,
although luminous intensity and resolving power of these objectives are not exhausted. If its full achievement is to be used, the
immersionskondensor head 1.3 must be used.
Operation:
•
Lower condensor lens 0.9 with impulse (fig. 1/14), screw wedging (fig. 3/30) solve and condensor lens including a trailer of the stand
remove. Upper section of the condensor lens 0.9 abschrau ben and by condensor lens head 1.3 replace. Condensor lens and in trailer
of on the left of again into the swallow guidance insert, to the right in correct fit fold, downward attack taps to mount let and with
Rändelschrau fuel element (30) wedge.
Or
If the overview condensor lens 0.12 in working position rests
►
(6), prevent a perpendicularly oriented tap that this rest will over-
drive. This taps - nachdemman - removed the condensor lens A TRAILEr herausschrau ben and away-put. Install afterwards a trailer
the stand, as described above. Advantage: The condensor lens 0.9 can be swung out now fully to the left; it will accessible, in order to
exchange its upper section against the condensor lens head 1.3 and/or always-crave around the condensor lens head comfortably.
Apply a drop immersion oil on the Frontlinse of the Konden of sorkopfes (favourably apply a further drop on the lower surface of
the slide - drops in work situation hanging!).
Condensor lens head (over change mechanics swing if necessary) in work situation lift, to the area between
Condensor lens front surface and slide lower surface are with oil-filled out.
Lighting after Köhler stop.
Aperture diaphragm fully open! (Again reduced Konden sorapertur would waive the advantage of the condensor lens immersion
again). The condensor lens head 1.3 can be used also drying. Maximum aperture into this case approx. 0,8.
