Continuous scintillator slab with microchannel plate PMT for PET

A PET detector design using the continuous scintillator slab was investigated. The detector unit consists of two layers of LSO scintillator slab, each slab size of 102×102×5mm³, and two large area microchannel plate (MCP) PMTs, 102×102mm², coupled to scintillator slabs. The optical photon inside scintillator was simulated using Geant4 package and the electrical signal of MCP was formed using the measured characteristics of MCP and Geant4 output. The signals from MCP were readout using the transmission line (TL) scheme with 4.25mm pitch. The multi-layers of structure enable us to extract the depth of interaction in addition to position, energy and timing in an event. The detector response was measured by impinging the pair of 511keV gamma upon the detector. As preliminary results, we obtained ~12% (FWHM) of energy resolution at 511keV and ~360ps (FWHM) coincidence timing resolution while keeping 14% detection efficiency at 511keV. The position resolution was measured ~2.3mm (RMS) at the center. Due to its simplified structure, the detector can be easily extendable to several layers of slab to increase the sensitivity. The fast timing characteristics of MCP combined with the high sensitivity of LSO makes this design reliable for TOF PET application.