Zeiss Axiotech, Руководство по эксплуатации

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Carl Zeiss Axiotech and Axiotech
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3-38 B 40-020 e 06/99
3.7 Measuring, counting and comparing techniques using the microscope
3.7.1 Length measurements using stage micrometer and crossline micrometer
The measurements of lengths using the Axiotech/Axiotech
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requires the following, for example:
•
stage micrometer for reflected light, 5 + 100/100 y, and
•
eyepiece crossline micrometer 10: 100, d = 26 mm
An overview of stage micrometers and eyepiece reticles available from Carl Zeiss is given in chapter 1.6.
Before the length measurement using the microscope can be performed, the micrometer or scale value
of the used objective / eyepiece combination must be determined. This scale value is exactly that distance
in the specimen which complies to one interval of the used eyepiece crossline micrometer.
☞
The distance to be measured should be
≥
5 mm in the intermediate eyepiece image in order to
keep the influence of random measuring deviations as low as possible. Other measuring errors
can occur if the eyepiece has not been inserted into the tube until stop.
For calibration, align the scales of the stage micrometer and the crossline micrometer parallel to each
other by turning the eyepiece, and make the zero lines of both scales exactly congruent. If, for example,
99 increments (of 10 µm each) of the stage micrometer correspond to exactly 100 increments of the
crossline micrometer, as shown in Fig. 3-33, the resulting scale value k’ for the used objective / eyepiece
reticle combination (A-Plan 10
×
/0.25 and crossline micrometer 10 : 100) is:
k' =
99
100
×
10 µm = 9.9 µm.
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 eyepiece crossline micrometer (estimated:
one tenth) multiplied with the scale value k’:
L = 35.5
×
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 a calculation from a combined
x- and y-measurement (Pythagoras).
Fig. 3-33 Measurement of lengths