GE Healthcare eXplore Locus SP, Руководство по обслуживанию

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VERIFY STAGE TIP (SIDE-TO-SIDE MOVEMENT)
32. Move the ball toward the X-Ray Source ( 140mm right ).
33. Elevate and rotate the tool until the top bebe appears in the centre of the screen.
34. Use the mouse pointer window as a reference guide and rotate the bebe 180°.
The goal here is to have the bebe return to the same x axis after the 180° rotation.
35. Continue to reposition the bebe until it is close to returning to the same x axis.
It may be necessary to rotate the bebe less than 0.1 degree to get it in the exact centre. To
make movements that are finer than 0.1 degree access the
X-Ray and Motor Controller and
adjust the Steps to Travel field (e.g. 50) which are steps in the stepper motor. Adjust the
Direction and press the Start Motor button.
The next goal is to confirm that, at the X-Ray 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.
36. Once the bebe is properly positioned in the x direction, capture the image, correct and unwarp
it. Open the image in MicroView and determine the y axis of the bebe using the Region Grow
tool in MicroView . Record value in Worksheet. This y axis must be the same as the Central
Slice value (within 2 pixels).
To find the calculated Central Slice, in Calibration Tools , click on the Calib. Settings tab. Click
File and choose Read Registry Values from the drop-down menu. The calculated Central Slice
value is found beside Central Slice1.
If the y axis position is not the same value as the Central Slice (within 2 pixels):
37. Continue to adjust the elevation - capturing, correcting, unwarping, and viewing the images in
MicroView - until the y axis is within 2 pixels of the Central Slice value. Use the Steps to Travel
field within X-Ray and Motor Controller to make movements finer than 1mm.
Once the y axis position equals the value as the Central Slice (within 2 pixels):
38. Rotate the tool 180° and capture, correct, unwarp and view the image in MicroView . The value
of this y axis position must be within 2 pixels of the previous value before rotation. For example,
if the previous y axis was 1428, this y axis position may have a value between 1426 and 1430.
Also, verify the x value are within 5 pixels of each other.
Note: If not within 2 pixels, verify the Central Slice position before making any adjustments, as
follows.
after 180° rotation after 180° rotation