Hitachi Microscope & Magnifier S-4800 Manual De Usuario

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3.3    Application of High Voltage 
 
3.3.1    Condition where the gun high voltage is applicable 
 
You can apply high voltage when the HV display area on the control panel is blinking with yellow 
and blue colors. When the indication is blue, high voltage can not be applied. It will be in almost 
case because of vacuum degradation of specimen chamber or gun ion pumps. Also the 
specimen exchange chamber must be evacuated and the gate valve must be closed.   
While high voltage is applied, the indication is shown in yellow color. 
 
 
3.3.2  Flashing 
 
3.3.2.1 About flashing 
Flashing is a procedure for removing gas molecules which have been adsorbed on the surface of 
the cathode (FE tip) in the electron gun. 
Flashing is needed as follows. 
 
(1) Flash once everyday before use 
When the emission current becomes unstable, flash again. 
 
(2) Flash once at the end of daily operation 
On the next day, start operation without flashing. Flash if the emission current becomes 
unstable during operation.
 
3.3.2.2  Flashing Procedure 
 
Use the following procedures for flashing. 
 
(1) Click the HV display area on the control panel. The HV control dialog window will open. 
 
 
(2) Click the Flashing button on it. The Flashing execution dialog window will open.