Hitachi Microscope & Magnifier S-4800 Benutzerhandbuch
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select a number from the pull-down menu, click on the up and down button (0.1 step), or key
in a number (0.5 to 2.0) followed by the Return key.
Note that the optical axis and astigmatism may change when Focus Depth value is changed.
NOTICE: Because the primary beam is more sensitive to stray magnetic field as the Focus
Depth increases, large values of the Focus Depth may cause image disturbance due to stray
magnetic field in high magnification observations.
in a number (0.5 to 2.0) followed by the Return key.
Note that the optical axis and astigmatism may change when Focus Depth value is changed.
NOTICE: Because the primary beam is more sensitive to stray magnetic field as the Focus
Depth increases, large values of the Focus Depth may cause image disturbance due to stray
magnetic field in high magnification observations.
(5) Specimen Bias Voltage
Normally, it is set to OFF (uncheck the box). Select ON (check the box) when non-uniformity
of brightness appears on the CRT at low magnifications in high mag. mode under the
conditions where the sample is tilted at high angles of 40 degrees or higher. Additionally select
on especially when observing at high accelerating voltage such as 10 kV or higher. When
the specimen bias voltage is on, -15 V is applied to the sample.
of brightness appears on the CRT at low magnifications in high mag. mode under the
conditions where the sample is tilted at high angles of 40 degrees or higher. Additionally select
on especially when observing at high accelerating voltage such as 10 kV or higher. When
the specimen bias voltage is on, -15 V is applied to the sample.
NOTES:
1. When the Specimen Bias Voltage is turned on at low accelerating voltages, SEM
image may become dark because the detection efficiency of the SE signal is
decreased. We suggest that you set the Specimen Bias Voltage at OFF in order
to correct this problem. To improve the non-uniformity of brightness in the
image which may appear at high sample tilt condition, at low magnifications and
at low accelerating voltages, it is recommended to use the Low mag. mode.
decreased. We suggest that you set the Specimen Bias Voltage at OFF in order
to correct this problem. To improve the non-uniformity of brightness in the
image which may appear at high sample tilt condition, at low magnifications and
at low accelerating voltages, it is recommended to use the Low mag. mode.
2. Turning Specimen Bias Voltage ON and OFF may cause changes in the contrast
of the image depending on the application.
3. Turning Specimen Bias Voltage ON and OFF may cause changes and require
adjustment of the focus, astigmatism and aperture alignment.
4. If
the
ABCC Link check box in the Column Tab has been checked, ABCC will
start automatically when Specimen Bias Voltage is changed.
Image brightness will be adjusted to adequate value.
Image brightness will be adjusted to adequate value.
(6) Magnet Sample
Astigmatism correction range is enlarged. Use it for observation of ferromagnetic specimens
such as iron that make astigmatism correction difficult.
such as iron that make astigmatism correction difficult.
CAUTION
Pulverized ferromagnetic specimens should not be introduced into
the specimen chamber. If particles from such a material are
attracted to the objective lens due to its strong magnetic field, the
microscope performance may be degraded.
Because ferromagnetic samples strongly interact with the magnetic
field of the objective lens, they should be attached firmly to the
specimen stub.
the specimen chamber. If particles from such a material are
attracted to the objective lens due to its strong magnetic field, the
microscope performance may be degraded.
Because ferromagnetic samples strongly interact with the magnetic
field of the objective lens, they should be attached firmly to the
specimen stub.
NOTICE:
If a ferromagnetic sample is large in volume, Magnetic Sample mode may fail to
achieve complete astigmatism corrections, or may not provide an adequate
achieve complete astigmatism corrections, or may not provide an adequate