Siemens SOMATOM Manual page 50

Dose Information
2) Angular tube current modulation:
Based on the above described axial eff. mAs profiles,
the tube current is modulated during each tube rota-
tion. Therefore the angular attenuation profile is mea-
sured automatically during the scan and the tube cur-
rent is modulated accordingly in real time to achieve
an optimum distribution of the X-ray intensity for every
viewing angle.
constant dose
rel. attenuation
reference attention
Relation between relative attenuation and relative
tube current. The adaptation strength may be
adjusted by user separately for the left branch (slim)
and the right branch (obese) of the curve. This adjust-
ment effects all examinations. The gray lines here
indicates the theoretical limits of the adaptation (con-
stant dose resp. constant image noise). The absolute
(eff.) mAs value is scaled with the Image Reference
mAs value, which may be adjusted in the Scan Card by
the user.
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