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Description of the Microscope
9
MIRA3 FEG-SEM
4.1.1
Electron Column Displaying Modes
RESOLUTION Mode
This is the basic and most common displaying mode. The IML lens is switched off, the OBJ
lens is excited and it focuses the final electron beam.
Characteristic:
high resolution
low depth of focus
The MIRA3 works like the other common three lens microscopes
without IML in this mode. The aperture is nearly optimal for lower
BI values (small spot size, low beam current) short working
distances (4-5) mm and for the accelerating voltage 30 kV. The
pivot point of the scanning and the electric image shifts are close
to the principal plane of the objective OBJ so that the curvature
of the field, distortion and field of view are as good as possible.
The centering of the objective OBJ is performed by defined beam
tilt of the central electron beam, which does not cause image shift.
This mode is intended for displaying with the highest resolution.
Содержание MIRA3
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