Planmeca Proline EC ceph, Техническое руководство

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Chapter D - ADJUSTMENT & CALIBRATION
D-12 Planmeca Proline EC X-ray unit
PATIENT POSITIONING MECHANISM
Technical Manual
Take an exposure. Hold the exposure down for the duration of the exposure.
CAUTION Radiation is generated when exposure button is pressed.
Press the return key to drive the cassette to the loading position, remove the cassette and
process the film.
The images of 23 balls should appear on the film. They should be round, all the same size,
and evenly spaced. Note that they will not necessarily be at the same vertical height. The dis-
tance from the center of the middle ball to the center of the tenth ball to the left and the tenth
ball to the right should be 120mm ± 2mm. If this distance is correct then the patient position-
ing mechanism need not be adjusted, and you should then check the patient positioning lights
(see section “FOCAL TROUGH POSITIONING LIGHT” on page D-23).
Figure 14
If these distances are not correct you will have to adjust the position of the patient positioning
mechanism. The following diagrams are a rough guide as to how to position it correctly. Note
that you may have to make more than one adjustment as the patient positioning mechanism
could be incorrectly positioned in more than one direction. For example it may be too far for-
ward and too near the column.
If the distance from the middle ball to the center of the tenth ball on the left-hand side is more
than 122mm and on the right-hand side less than 118mm then the patient positioning mecha-
nism must be moved away from the column.
Figure 15
120±2mm 120±2mm
Film
Right-hand side
Film
Less than 118mm
More than 122mm