GE Healthcare eXplore Locus SP, Service Manual

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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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Verify the Central Slice position:
- rotate the tool back 180 degrees
- move the stage 140mm toward the detector
- capture an image, correct and unwarp it
- load the image into MicroView and check that the y position is the same within 2 pixels. If
the y position is not at the Central Slice at the detector end, the Central Slice calculation
will need to be redone.
Verify all values before redoing the Central Slice calculation.
If the y axis is not within 2 pixels of the previous value and the Central Slice calculation is
verified:
- Move the stage back 140 mm toward the Source.
- Mechanically adjust the stage using the stage levelling screws (capturing, correcting,
unwarping and viewing an image after each adjustment). Move the stage to the centre
(70mm toward the detector) in order to mechanically adjust the stage.
- Continue to adjust the stage and view the results until the y axis is within 2 pixels of the
previous value after 180° of rotation.
The end result is that at the Source end the y values at 0 and 180 degree rotation are within 2
pixels of each other and within 2 pixels of the Central Slice, AND the y axis at the detector end
is within 2 pixels of the Central Slice.
39. Once the values are within 2 pixels of each other, capture and save an image after each
rotation and call the files Tip1 and Tip2 .
7.3.2 Centre the Stage
This procedure is used to centre the stage between the X-Ray Source and the detector. With the
X,Y Centring Ball tools still mounted and the X-Ray Source on:
1. Click on the Turn X-Ray Off button, then
physically rotate the X,Y Centring Ball tool so
that 2 of the 4 adjustment screws are exactly
perpendicular to the detector (i.e. not at an
angle).
2. Elevate the tool using the Elevation feature in
X-Ray and Motor Controller until the ball
appears in the centre of the Fluoro display.
Move the stage 70mm toward the detector so
that it is positioned in the middle between the
Source and detector.
top view