@misc{oai:repo.qst.go.jp:00069371,
 author = {Shibuya, Kengo and Nishikido, Fumihiko and Inadama, Naoko and Yoshida, Eiji and Lam, ChihFung and Tsuda, Tomoaki and Yamaya, Taiga and Murayama, Hideo and 澁谷 憲悟 and 錦戸 文彦 and 稲玉 直子 and 吉田 英治 and Ｌａｍ ＣｈｉｈＦｕｎｇ and 津田 倫明 and 山谷 泰賀 and 村山 秀雄},
 month = {Nov},
 note = {Depth-of-interaction (DOI) PET detectors possess three-dimensional information on the interaction point of annihilation radiation and a scintillator crystal. The information has been used for improving PET spatial resolution especially at the edge of field-of-view. In this paper, DOI information is used for improving timing resolution of scintillation detectors. The annihilation radiation travels at the light speed, c, while scintillation photon travels at the speed of c/n in medium, where n is the refractive index. The difference in the propagation speed causes timing error which depends on the DOI. Given that the total length of the scintillator is 3.0 cm and the refractive index is 1.8, the error is estimated to be 80 ps or longer. We experimentally evaluated the timing error as the function of the DOI by using Pseudo-four-layer DOI detector and a fast digital oscilloscope. The detector was composed of an LYSO scintillator crystal and 255 dummy crystals made of silica. As the result, the error was estimated to be about 100 ps. Timing correction using DOI information would be an important technique when constructing high timing resolution PET detectors, especially ones for time-of-flight PET., IEEE 2007 Nuclear Science Symposium and Medical Imaging Conference},
 title = {Timing Resolution Improved by DOI Information in a Four-Layer LYSO PET Detector},
 year = {2007}
}