2017 Imaging for Physicists Coursebook

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%

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ESTRO Teaching Course Advanced Imaging: PET – Basic Principles