GE Senographe DS, Руководство пользователя

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Chapter 9 Page no. 1022
JC-TSG-A-010.fm
GE Healthcare Senographe DS
Revision 1 Service Information and Procedures Class A 2385072-16-8EN
Job Card TSG A010 - Troubleshooting Bad Pixel Calibration Failure
"Check if paddle is removed and the flat field phantom is positioned correctly"…
3-1-4-1 Typical Root Causes
1. The tube tilt calibration is not good.
2. The X-Ray tube housing is not well positioned on the pivots within the X-Ray tube.
3-1-4-2 Corrective Actions.
1. From the Service Desktop, select Calibration -> Detector -> Clear Calibrations . Follow the instruc-
tions to perform the clear calibrations procedure as indicated.
2. Perform Job Card CAL A027 - Tube Tilt Calibration on page 1681 , to re-calibrate the tube tilt.
3. If the problem persists, re-position the X-Ray tube housing to ensure that the left pivot is flush against
the housing, and that the right pivot has a tight fit. For more information, see Installation of X-ray
Tube Housing on page 1355 in Job Card D/R A261 - X-ray Tube Assembly
! Notice:
Make sure to strictly perform all calibration required for correction as stated in section 4 , Post-Cor-
rective Actions on page 1026 .
3-2 Troubleshooting - Failure at the End of Bad Pixel Calibration
Bad pixel calibration fails if one or more of the following defect categories have a Fail status:
• Isolated pixels
• Small clusters
• Medium clusters
• Large clusters
• 3*3 clusters
• Bad columns
• Bad rows
• Small cluster density
• Medium cluster density
• Local defect density (only for DS and Essential with the International detector).
One defect category FAIL means that the detector is above GE bad pixel specifications. The root cause
of the failure must be found before the customer can continue to work because there is a risk to loose
information in the clinical images.
The typical root causes for one or more defect categories to fail in bad pixel calibration are the following:
• The detector files are not correct (i.e. there is a detector ID mismatch)
• Dust on the detector, flat field phantom, filter wheel, or in the collimator
• Damaged flat field phantom
• Bad position of flat field phantom
• The collimator Blade shadow or the collimator blade itself
• Defective detector
If bad pixel calibration fails, use the decision tree in Illustration 2 , page 1023 along with the following sec-
tions to solve the issue.