Hitachi Microscope & Magnifier S-4800 User Manual
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brightness in the field of view. In such a case, decrease the size of the specimen,
use a longer WD, or lower the accelerating voltage in order to correct the
astigmatism.
use a longer WD, or lower the accelerating voltage in order to correct the
astigmatism.
(7) Degauss Operation
The Degauss operation eliminates hysteresis of the magnetic field in the objective lens.
When focus is changed greatly, accuracy of magnification or alignment of the electron optical
axis may degrade due to hysteresis of the focusing magnetic field. Click Degauss button in
the Column Tab under the following condition:
When focus is changed greatly, accuracy of magnification or alignment of the electron optical
axis may degrade due to hysteresis of the focusing magnetic field. Click Degauss button in
the Column Tab under the following condition:
•
After changing focus widely.
•
Before making the electron optical axis alignment.
Degaussing is automatically effected when WD is changed in the Column Tab or OPE-
CONDITION Block, when the accelerating voltage is changed, or when the Probe current
mode is changed.
CONDITION Block, when the accelerating voltage is changed, or when the Probe current
mode is changed.
(8) Setting of ABCC Link
Used for setting whether or not to automatically adjust brightness and contrast (ABCC) upon
changing the following status.
(a) Probe Current mode
(b) Specimen bias voltage
(c) Detector setting
(d) Magnification mode (High Mag/Low Mag)
changing the following status.
(a) Probe Current mode
(b) Specimen bias voltage
(c) Detector setting
(d) Magnification mode (High Mag/Low Mag)
3.4.2.2 Low Mag Mode
Probe Current mode and Cond Lens1 are set as same
manner
as in the HIGH MAG MODE area.
These are selectable independently to High mag mode because in general the Low mag mode
brings less bright image if operated with the same column condition.
brings less bright image if operated with the same column condition.