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Software control: Microscope Control
3-24
User Manual
C O N F I D E N T I A L –
limited rights
Feb 2018
Revision A
Column Use cases
The electron column can be operated in different column Use cases optimized for
specific applications. Selecting a desired Use case can be done with the
toolbar
/
Use
case
drop down list box and also within the Use Case module (see Chapter 5).
Magnification (HFW) / High voltage /
Spot size (Beam current) list boxes
Click on the list box to expand a list of pre-set and allowed values.
Choose one by clicking on it; it is applied immediately (see the
Preferences / Presets
section).
•
The
Spot
is defined as the actual electron beam diameter on the
specimen surface. It is expressed by a relative number. The optional
way (representable in the toolbar) to express the Spot is the
electron beam current value. (see the
Preferences
dialog /
General
section /
Beam current control
item). Both physical quantities are
related. The electron beam current shown in the toolbar list box
(and optionally in the image databar) is approximate and is valid
only if the microscope is well-aligned.
Imaging pixel resolution list box
This list contains the available imaging pixel resolutions (also used for captured images). Selecting
a new resolution results in the immediate change of the scanning raster. Since the present dwell
time remains unchanged, the actual scanning frequency (both Line and Frame time) changes.