Справочник Пользователя для Hitachi Microscope & Magnifier S-4800
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(3) Set Intensity to “2” and click Execute button.
The emission current value caused by flashing will be displayed on the Ie part of the HV
Display area about 2 seconds.
For normal flashing operation, use intensity “2”. However, when the stable stage of the
emission current is short, or the emission current begins to increase about 1 hour after
applying HV (in that case a large quantity of gas molecules are absorbed on the cathode), use
intensity “3”.
Display area about 2 seconds.
For normal flashing operation, use intensity “2”. However, when the stable stage of the
emission current is short, or the emission current begins to increase about 1 hour after
applying HV (in that case a large quantity of gas molecules are absorbed on the cathode), use
intensity “3”.
After flashing, the emission current decreases for a while, then becomes stable. (Even in the
stable period, the emission current continuously decreases slightly.) The emission current
becomes unstable and increases after 5 to 10 hours of operation.
Noise (bright or dark lateral stripes on the image) may appear in the initial period, but will
disappear in the stable period. When there is a large amount of noise and the emission current
becomes unstable, turn HV Off, and flash again.
A message will appear when 8 hours of accumulative operation time or 24 hours of total time
passed after flashing, as a reminder to flash the tip again.
If the tip is not flashed within 30 minutes, the HV will be turned off automatically.
The time period can be set at other value if necessary. Contact a service engineer to change the
time.
3.3.3 Setting of Accelerating Voltage and Emission Current
To set the accelerating voltage and emission current, use the HV Control dialog window.
(1) To set an accelerating voltage, select a voltage from the Vacc list box. Accelerating voltage
can also be set by using the keyboard to input a value followed by the Return key.
Also Up/Down buttons beside the listbox are available for 100V step setting.
Also Up/Down buttons beside the listbox are available for 100V step setting.
(2) To set an emission current, select a current in the Set Ie to list box. It is recommended to set
it at 10 µA for normal operation.
Accelerating Voltage Emission Current
Both accelerating voltage and emission current are adjusted immediately upon changing
them if the HV is on.
them if the HV is on.