@misc{oai:repo.qst.go.jp:00076862,
 author = {Kang, Hangyu and Nishikido, Fumihiko and Yoshida, Eiji and Sakai, Toshiaki and Yamaya, Taiga and Kang, Hangyu and Nishikido, Fumihiko and Yoshida, Eiji and Yamaya, Taiga},
 month = {Oct},
 note = {In the previous work, we developed a high resolution depth of interaction (DOI) positron emission tomography (PET) detector called X’tal cube by using 3D subsurface laser engraving (SSLE) technique [1]. However, the X’tal cube requires a long 3D laser processing time and six SiPMs for readout. Moreover, the gaps between the detector blocks result in a sensitivity loss. In this study, we propose a novel SSLE based trapezoid geometry DOI PET detector which can solve these issues by using stacking of 2D SSLE processed LYSO plates and dual-ended readout approaches. A 20 mm long monolithic trapezoid LYSO plate (Top: 15.3 mm, bottom: 25.6 mm, thickness = 0.9 mm) was segmented in 15 × 10 (DOI) array by using SSLE to yield a top crystal pitch of 1.02 mm, a bottom crystal pitch of 1.71 mm, and 2.0 mm DOI bin, respectively (Fig. 1). Three laser processed LYSO crystal plates were stacked and optically isolated by using ESR film. A 7×6 array SiPM (pitch=2.4 mm) and 8×4 array SiPM (pitch=3.2 mm) were coupled to the top and bottom of the trapezoid LYSO array, respectively (Fig. 1). The DOI information was extracted by using the signal amplitude ratio of the two SiPMs (top and bottom). All the LYSO segments could be identified in the flood map (Fig. 2(a)). The DOI resolution and energy resolution were measured to be 2.0 mm and 11.4%, respectively (Fig. 2(b) and 2(c)). In future, a prototype submillimeter resolution small animal PET scanner will be developed by using the SSLE based trapezoid shape dual-ended readout PET detector., 15th Int. SCINT 2019},
 title = {A sub-surface laser engraving based trapezoid geometry DOI PET detector},
 year = {2019}
}