Optimization of optical coupling conditions for LSO/LuYAP phoswich detector

Phoswich detectors consisting of LSO and LuYAP for small animal PET have been developed to measure the depth of interaction (DOI) and to improve spatial resolution. The aim of this study was to characterize the optical coupling condition between phoswich crystal and photomultiplier tube (PMT) and between LSO and LuYAP to improve the performance of LSO/LuYAP phoswich detector. Light yields and DOI measurement errors of the phoswich detector with various optical coupling conditions were investigated by simulation and experiment. Additionally, the effects of inserted materials between LSO and LuYAP crystals with various ratios of coverage and surface conditions on PET performance were investigated