Hitachi Microscope & Magnifier S-3400N User Manual

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3.10.1 
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3.10  Image Quality 
 
The following are references for getting better image quality. 
 
 
3.10.1    Accelerating Voltage and Image Quality 
 
There is a multitude of accelerating voltages to choose.    Resolution, image quality, charging 
and other effects are greatly determined by the selected accelerating voltage.    Below is a 
guideline for selecting an accelerating voltage with which to image various specimens. 
 
Table 3.10-1    Accelerating Voltage and Image Quality 
 
Acc. volt. 
(kV) 
1   2   3   5 
10   15   20   25 
30 
Resolution 
Low 
 
 
Secondary electron signal 
High 
 Low 
Surface information 
Topmost surface 
info. 
 
Surface info. (incl. 
internal info.) 
Influence of contamination 
※1 
High 
 Low 
Charge-up 
※2 
Low 
 High 
Non-deposition observation 
※2 
Easy 
 
 
Specimen damage 
※2 
Low 
 High 
Influence of floating 
magnetic filed 
High 
 Low 
X-ray analysis 
 
X-RAY 
 
 
※1:  Under a low accelerating voltage, information is at the topmost surface. When there is 
contamination, that surface is observed, exerting significant impact on the image. 
 
※2:  The extent of this factor is subject to change depending on the type of specimen involved 
and the type of specimen pretreatment conducted. 
 
 
High