Zeiss Standard 25 ICS, Руководство по эксплуатации

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Standard 25
ICS
3-10 B 40-029 e 01/98
3.6 Measurement of lengths
The measurement of lengths using the Standard 25 ICS requires the following, for example:
stage micrometer, positive 5 + 100/100 y D = 0.17 mm
and
eyepiece crossline micrometer 10:100, d = 26 mm
An overview of available stage micrometers and eyepiece reticles 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 reticle 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.
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 20 µm each) of the stage micrometer correspond to exactly 100 increments of the
crossline micrometer, as in Fig. 3-10, the resulting scale value k’ for the used objective / eyepiece reticle
combination (A-Plan 10x/0.25 and crossline micrometer 10:100) is
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 may occur if the eyepiece has not been inserted into the tube until
stop.
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 (tenth
estimated) multiplied by the scale value k’.
Example:
L = 35.5 x 9.9 mm = 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).
Fig. 3-10 Measurement of lengths
k' =
99
100
x 10 m = 9.9 m