@misc{oai:repo.qst.go.jp:00068227,
 author = {Ono, Yusuke and 小野 裕介},
 month = {Oct},
 note = {The jPET-D4 detector module consists of four layers of 16 x 16 Gd2SiO5 (GSO) crystals and 256 channel flat panel position sensitive photomultiplier tube (256ch FP-PMT). Each crystal element is in dimensions of 2.9mm x 2.9mm x 7.5(or 7.2) mm and crystal identification in the crystal block offers detected location 3-demensionaly. Two kinds of GSO crystals having different Ce dopant concentration are used in the upper and lower two layers in order to distinguish these layers by pulse shape discrimination. Proper reflector insertion in the crystal block then enables to identify crystals of detection in each two layers.
For mass production of the depth of Interaction (DOI) crystal block composed of 1024 crystal elements with proper reflector arrangement, we designed appropriate tools which promote simple construction as well as uniform configuration. The four of crystal layer assembled with the tool are coupled in depth by RTV rubber and adjusted external size with another tool. The construction took only 3 hours per one crystal block. To estimate reliability of the construction method, uniformity of pulse shape discrimination, energy resolution and light output were studied on 120 crystal blocks actually constructed in the method., Nuclear Science Symposium  & Medical Imaging Conference},
 title = {The jPET-D4: Simple and reliable construction method for 4-layer DOI crystal blocks},
 year = {2005}
}