@misc{oai:repo.qst.go.jp:00064270,
 author = {Tashima, Hideaki and Katsunuma, Takayuki and Kinouchi, Shoko and Suga, Mikio and Obi, Takashi and Kudou, Hiroyuki and Murayama, Hideo and Yamaya, Taiga and 田島 英朗 and 勝沼 隆幸 and 木内 尚子 and 菅 幹生 and 小尾 高史 and 工藤 博幸 and 村山 秀雄 and 山谷 泰賀},
 month = {Jul},
 note = {We have proposed the OpenPET geometry which has gaps between detector rings and physically opened field-of-view. The image reconstruction of the OpenPET is classified into an incomplete problem because it does not satisfy the Orlov's condition. Even so, the simulation and experimental studies have shown that applying iterative methods such as the maximum likelihood expectation maximization (ML-EM) algorithm successfully reconstruct images in the gap area. However, the imaging process of the iterative methods in the OpenPET imaging is not clear. Therefore, the aim of this study is to analytically analyze the OpenPET imaging and estimate implicit constraints involved in the iterative methods. To apply explicit constraints in the OpenPET imaging, we used the method of convex projections for restoration of the images reconstructed by the analytical way in which low-frequency components are lost. Numerical simulations showed that the similar restoration effects are involved both in the ML-EM and the method of convex projections. Therefore, the iterative methods have advantageous effect of restoring lost frequency components of the OpenPET imaging., Fully ３D　１１},
 title = {Restoration of the Analytically Reconstructed OpenPET Images by the Method of Convex Projections},
 year = {2011}
}