Technical Manual: TM50567
Optica 30/40/50 series
Revision: 4.0
Date of release: 2019-01-23
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Collimator Adjustments
Accuracy of the Light field indication to X-ray field
The Collimator X-ray field and the light field are factory calibrated. Ensure the calibration meets local
legislation.
Calibration setting:
The total discrepancies between the edges of the X-ray field and the corresponding edges of the Light
Field do not exceed 2% of the distance of the measured plane of the Light Field from the Focal Spot.
Verification of the Light field indication to X-ray field
The X-ray images taken in §3.10 are used to verify the light field to X-ray field accuracy.
In case the light field does not match the X-ray field, perform the following:
Check the if distance (spacing) from the focal spot of the X-ray tube to the collimator mounting
plane is 80 ± 1 [mm] (3.15 " ± .039 "):
1.
Light field larger than X-ray field:
Remount the collimator to the X-ray system (see §3.8) using less spacer(s) and repeat the test
image procedure (see §3.10) and verify the sizes.
2.
Light field smaller than X-ray field:
Remount the collimator to the X-ray system (see §3.8) using additional spacer(s)and repeat
the test image procedure (see §3.10) and verify the sizes.
Field light size fine adjustment
Fine adjustment of the field light size can be done after removal of the rear panel (see §3.5). The field
light size can be adjusted by loosening the positioning screws of the field light bracket as indicated in
Figure 8. Adjusting is done by means of 2 screws, socket head wrench (size 2).
After the field light size is adjusted, carefully tighten the positioning screws without moving the field
light.
Figure 8 Field light adjustment
