Del Medical EPEX Omniflex IV, Service Manual

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EPEX/Omniflex IV System Service Manual
4-30 Adjustments and Calibration
Aligning the Collimator Light Field to the X-ray Field
Note: If the light field to the
X-ray is too small, refer to the
Collimator service manual
that came with the system.
To align the Collimator light field to the X-ray field:
Figure 4-6.
Example of Alignment
at 1%
Step Action
1 Set SID to 100 cm.
2 Adjust the Collimator shutters so that the edges of the light field
coincide with the rectangular outline of the Collimator test tool.
Note: Ignore the Collimator crosshair.
3 Initiate an exposure at approximately 60 kVp and 8 mAs.
4 Accept the image.
5 View the image in DRIVEL.
If the X-ray field falls just within the image of the rectangular
frame,
there is good alignment. Refer to Figure 4-6.
If an edge of the X-ray field falls on the first spot,
±
1 cm on either
side of the line, the edges of the X-ray and light fields are
misaligned by 1% of the distance between the X-ray source and the
Bucky.
An edge falling on the second spot,
±
2 cm, indicates an error of 2%
at 100 cm. The maximum allowed misalignment is 1% of the source
to image distance.