@article{oai:repo.qst.go.jp:00045459,
 author = {Yamaya, Taiga and Inaniwa, Taku and Yoshida, Eiji and Nishikido, Fumihiko and Shibuya, Kengo and Inadama, Naoko and Murayama, Hideo and 山谷 泰賀 and 稲庭 拓 and 吉田 英治 and 錦戸 文彦 and 澁谷 憲悟 and 稲玉 直子 and 村山 秀雄},
 issue = {5},
 journal = {Physics in Medicine and Biology},
 month = {Mar},
 note = {We have proposed an 'OpenPET' geometry which consists of two detector rings of axial length W each axially separated by a gap G. In order to obtain an axially continuous field-of-view (FOV) of 2W+G, the maximum limit for G must be W. However, two valleys of sensitivity appear, one on each side of the gap. In practice, the gap should be G<W in order to compensate for the sensitivity valleys. In this paper, we proposed an alternative method to improve uniformity of the sensitivity while maintaining the gap. The proposed geometry consisted of four units of detector rings obtained by dividing each right and left unit of detector rings into two units. The inner two units formed the main gap, and the outer two units were appropriately placed to improve the uniformity of sensitivity. The geometry was optimized to minimize the standard deviation of the sensitivity distribution. Numerical simulation results supported the effectiveness of the proposed method. The outer units compensated for the sensitivity valleys on both sides of the main gap. A more appropriate geometry should be designed for the desired application, such as a long axial FOV PET and in-beam PET.},
 pages = {1223--1233},
 title = {Simulation sutudies of a new 'Open PET' goemetry based on a quad unit of detector rings},
 volume = {54},
 year = {2009}
}