1044 / 1359
z
max
Ideal situation
:
When changing the irradiation
conditions the reading of the in vivo
detector changes in the same
proportion as changes the i.c.
reading
calFT)
wedge,
SSD,
R(r,
T)
wedge,
SSD,
(r,
ent
D
=
Reality
:
Detector+
build up
response
dependence in dose rate, energy,
temperature may differ of those of
an i.c.
Due to the calibration geometry the
detectors “see” different scatter
conditions.
Calibration: Entrance dose
dose at the depth of dose maximum