Zeiss Axioskop 2, Руководство пользователя

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OPERATION
Quantitative microscopy Axioskop 2 / Axioskop 2
MOT
3-52 B 40-075 e 06/98
After exchange of the stage micrometer for the
specimen to be measured, the measuring distance
of interest results from the number of increments
of the crossline micrometer (tenth estimated),
multiplied by the scale value k’. Example:
L = 35.5 x 9.9 µm = 351.5 µm
Particularly large object structures can also be
determined by using the vernier scale gradations
(0.1 mm) on the mechanical stage. Here, it might
be necessary to determine the distance to be
measured through calculation from a combined x
and y measurement (Pythagoras).
3.7.2 Height measurement
Height measurements using the microscope are always possible to be performed if both the lower and
upper side of the specimen can be focused. This should preferably be performed using a precision
(Harmonic-Drive-) focusing drive and a high-aperture objective with a low depth of focus.
The difference in the stage height results in a height value for transmitted-light specimens which is
falsified by the refractive index of the specimen (through which focusing was made) and perhaps by the
immersion oil. The correct height value d of the specimen measured in transmitted light results from the
difference in the stage height (focus difference) d’ and the refractive indices n
P
of the specimen and n
M
of the medium between cover slip and specimen:
d = d’ x
Fig. 3-33 Length measurement using scale 1
on the stage micrometer (object)
and scale 2 on the crossline
micrometer (eyepiece)
n
P
n
M
1 2