Hitachi Microscope & Magnifier S-4800 Manual De Usuario

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3.4    Optimizing the Electron Beam 
 
3.4.1    Selecting a Magnification Mode 
 
S-4800 provides two magnification modes, High Mag mode and Low Mag mode. Magnification 
range of the modes are as follows.     

High Mag Mode (HM) 

:   

×

300 to 

×

800,000  

(The lowest and highest magnification will be changed depending on present 
accelerating voltage and working distance) 

Low Mag Mode (LM) 

:   

×

20 to 

×

10,000 

Use the High Mag mode for usual observation, and the Low Mag mode for field searching.   
 
Electron optical column conditions are set for both modes independently.     
 
3.4.2    Selecting Electron Optical Column Condition 
 
Electron optical column conditions need to be selected before alignment and operation of the 
SEM begins.   
For High Mag mode, use the OPE-CONDITION block on the Operation panel, and the Column 
tab of the Setup dialog window for further detailed setting .
For Low Mag mode, use the Column tab of the Setup dialog window . 
 
3.4.2.1 High Mag mode 
 
Items need to be set frequently are placed on the OPE-CONDITION block. 
 

(1) Probe Current mode 

Select Normal or High in the Probe Current mode selection box. Normal is for high resolution 
image observation. Use High for applications needs large probe current, such as EDX analysis.   

(2) Focus Mode 

Select UHR or HR.   
In UHR mode, full working distance range is available. At working distance range longer than 
about 8mm, the mode may cause somewhat rough focusing feeling.   
In HR mode, working distance range is limited to about 5mm or longer. The mode is easier to 
use at long working distance. 
 

(3) Working Distance (WD): 

Working distance (WD) is the distance between the bottom face of the objective lens and the 

Probe Current mode selection box 
Focus mode selection box 
WD(Working distance) set / indicate box 
WD range indication 
Condition Load / Save button 
Setup button