Hitachi Microscope & Magnifier S-4800 Manual De Usuario

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(1) Beam Alignment 
Beam Alignment is necessary in order to align the electron beam down the center of the 
electron optical column and through the center of the objective lens aperture. 
 
(a) Open the Alignment dialog window by clicking the 
  button on the Control Panel.   
(b) Click the Beam Align button in Alignment dialog window.    A circular image will appear. 
(c) Make adjustments with the alignment knobs (X and Y) or the mouse so that the circular 
image appears in the center of screen. 
Adjust
Circular image
 
 
(d) Turn off the Beam Align mode (click Off button in Alignment dialog window). 
 
 
NOTICE:  If a circular image does not appear even under the highest contrast setting, click 
Reset All button in the Alignment dialog window and change the first condenser lens 
to 16, and then carry out beam alignment.    Afterwards, change the first condenser 
lens to the desired value (normally, 5) and repeat the beam alignment. 
If the electron beam is not focused near the specimen surface, the circular image may 
be distorted or partially blocked.    In such a case, release the beam alignment (click 
Off button in the Alignment dialog window) and roughly adjust focus.   
 
If the circular image does not appear at all, perform a mechanical alignment.   
Assuming that you have done the beam alignment and presented an image at the 
center of the monitor.    If the image is circular, it is fine.    But if it is not a circular 
image or a part of the circle is missing even if setting higher contrast , try mechanical 
alignment following the instructions given in section 3.12. 
 
 
(2) Aperture Alignment 
Aperture Alignment is necessary to align the electron beam through the center of the objective 
lens. 
 
(a) Set the magnification to about 5,000× and position a point of interest in the center of the 
display. 
(b) Focus the image and correct astigmatism. 
(c) Click Aperture Align button in the Alignment dialog window and make adjustments so 
that the wobbling motion of the image is minimized. 
(d) Turn off the Aperture Align mode (click Off button in Alignment dialog window). 
 
NOTICE:  When you changed focus widely, it is recommended to perform degaussing of the 
3.4.2