GE Healthcare eXplore Locus SP, Руководство по обслуживанию

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GE H
EALTHCARE
D
IRECTION
5158821-100, R
EVISION
3
E
X
PLORE
L
OCUS
SP S
ERVICE
G
UIDE
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The next step is to find the Full Width Half Maximum value of this wire in pixels.
Note: All 4 wires must be symmetrical, but not necessarily completely round. How the wires appear may
give you a clue about a possible problem.
If, for example, 2 wires in diagonal corners look good but the other 2 do not, the centring of the stage
is not correct. If 3 of the wires look good and one looks bad, a possible error was made calculating
the distance between the X-Ray Source and the detector or the Detector Spacing under the Calib.
Settings tab is incorrect.
19. Press p to view the
plot.
If the resulting plot
is a straight line,
exit Microview and
repeat
reconstruction but
change z-size to 5.
20. Use the mouse
pointer to find the
number at the top
of the peak (e.g.
30000), and record
in the Worksheet.
21. Add the mean
value calculated
above in step 16 to
the peak value
(determined in the
last step) and then
divide the result by
2. This is the Full
Width Half
Maximum value. Record value in the Worksheet.
22. Zoom in (left-click and drag the mouse) so that the middle area of the peak is highlighted.
23. Move the mouse to the left line (side) and press 1 at the Full Width Half Maximum value point
(e.g. 15000).