GE CT-9800

GE MEDICAL SYSTEMS CT 9800 QUICK SYSTEM
Rev. 6 Direction 18000
6-10-12
--- Screws “A”, “B” and “C” can be turned the same amount in the same direction to move the mirror
into the beam
--- Screw “C” moves the beam into and out of the gantry.
--- Screws “A” and “B” moves the beam from side to side across the front of the gantry.
--- Screw “D” locks the adjustments in place.
Proceed as follows to align the sagittal alignment lights:
1. The notch in the teflon end of the laser alignment tool should be positioned at ISO with the left and right
internal axial light beams in the notch.
2. Remove the black cover from the sagittal alignment light assembly.
NOTE: There are 2 ways of accessing the screw adjustments for the sagittal light. You can approach
the adjustments from above after removing the gantry display board (e.g., stand on a step
ladder). Alternately, you can manually rotate the tube to the 3 o’clock position, adjust the
respective screws , close the gantry front cover, and check the beam position. Then repeat
this sequence for correction. The method of approach will be left up to the service engineer.
3. Turn on the alignment lights using the gantry test switch.
4. Back off locking screw “D” (Illustration 6-10-6)
5. If necessary adjust screws “A”, “B”, and “C” together in the same direction to move the mirror into the beam.
6. Adjust screws “A”, and “B” to position beam in the center of the lens. This is a preliminary rough adjustment.
CAUTION: Do not stare directly into the laser light port. instead, place
a piece of white paper over the port to verify that the beam is centered in the port
via the ”A” and ”B” adjustment screws.
7. Loosen the disc lens mounting screws at the front of the gantry cover.
8. Adjust screws “A” and “B” to move the beam from side to side until the beam lies within the white stripe along
the top of the laser light alignment tool (Ill. 6-10-2).
9. If the beam is scewed along the top of the alignment tool, rotate the sagittal lens located in the sagittal port of
the gantry cover to align the beam to the white stripe along the top of the alignment tool. Tighten the disc
lens mounting screws.
10. After this adjustment, the beam will be perpendicular to the scan plane and coincident with ISO.
NOTE: Remember that the beam may not necessarily coincide with the black
centerline stripe on the cradle.
11. Tighten the “D” locking screw.
12. Tighten the disc lens mounting screws.
13. Go on Coronal Alignment (sec. 10.7).