Fluke Biomedical 30-471 - Manual (Page 13)

Operation
Photon Detectors
2
2-5
18–25 MV Diodes
As seen in the following figure, the results are good for angle variations in the plane perpendicular to the
direction of the cable.
Gantry angle (degree with 180 being vertical)
Diode (type 474 [18–25 MV rated]) output vs. incident angle;
symmetric setup in 6 MV photons
Diode out
p
ut (n
ormalized
to
180°)
Gantry angle (degree with 180 being vertical)
Diode (type 473 [12–17 MV rated]) output vs. incident angle;
asymmetric setup cable faces collimator when at 90 degrees
Diode out
p
ut (n
ormalized
to
180°)