@misc{oai:repo.qst.go.jp:00064960,
 author = {Inadama, Naoko and Nishikido, Fumihiko and Hirano, Yoshiyuki and Yoshida, Eiji and Tashima, Hideaki and Murayama, Hideo and Nitta, Munetaka and Ito, Hiroshi and Yamaya, Taiga and et.al and 稲玉 直子 and 錦戸 文彦 and 平野 祥之 and 吉田 英治 and 田島 英朗 and 村山 秀雄 and 新田 宗孝 and 伊藤 浩 and 山谷 泰賀},
 month = {Apr},
 note = {X'tal cube is the PET detector we have developed and it has the capability of getting depth of interaction (DOI) information about radiation detected position in the detector. Fig. 1 illustrates the structure of the X'tal cube. It is composed of a scintillation crystal block and a number of multi-pixel photon counters (MPPCs) on the crystal block surfaces. A MPPC is thin and small enough not to interfere in radiation detection. The crystal block is segmented 3-dimensionally into small cubes. There is no reflector between the crystal segments so that scintillation light originating in a radiation detected segment spreads to all 6 surfaces and detected by all MPPCs. Simple Anger-type calculation can be used in position calculation for segment identification. By expressing results of the calculation with the all MPPC signals in a 3-dimensional (3D) position histogram, we get response corresponding to each crystal segment. 
In the first stage, we composed of the crystal block by fabricating a 3D array with small cubic crystal segments (array-XC). Later, we newly developed the laser processing technique to segment inside of a monolithic crystal block 3-dimensionally (laser-XC). In both ways, we have already confirmed that small segments such as 1.0 mm x 1.0 mm x 1.0 mm segments can be identified in the X'tal cube structure. Meanwhile, in a basic study, we found that scintillation light spreads in different manners between the array and laser-XCs due to different condition of optical discontinuity between crystal segments. Because different light distribution among MPPCs should result in different segment response positioning in the 3D position histogram, we reconsidered about the weight of Anger-type calculation to improve segment identification performance for the array and laser- XCs., 第105回日本医学物理学会学術大会},
 title = {Development of a DOI-PET detector X'tal cube: optimal position calculation for each optical condition in the scintillation crystal block},
 year = {2013}
}