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Photo-multiplier tubes (PMTs)
PMTs: photo-detectors used in scintillation
detectors for PET
(1) Incoming photon deposits its
energy at the photocathode,
release of a photo-electron
(2) Applied electric field
accelerates the electron to
the first dynode
(3) Emission of multiple
secondary electrons due to
increased electron energy
(4) …
Good signal-to-noise ratio (SNR)
Low quantum efficiency (QE) ~
25%
ESTRO Teaching Course Advanced Imaging: PET – Basic Principles
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