Hot Isostatic Pressed Gd₂O₂S:Pr, Ce, F Translucent Scintillator Ceramics for X-Ray Computed Tomography Detectors

Abstract

Translucent scintillator ceramics of Gd2O2S:Pr, Ce, F were fabricated using a hot isostatic pressing (HIP) technique. The optical transmission is about 60% of the incident light and the X-ray stopping power is also quite high. Owing to the enhancement of these properties by the HIP densification process, the highest light output from a 1 mm thick specimen combined with a silicon photodiode, when excited by 120 kV X-rays, has reached 1.8 times that of CdWO4 single crystals. The present ceramics are very promising candidates for scintillator materials in X-ray computed tomography (CT) detector applications.

Oxysulfide optical ceramics doped by Nd3+ for one micron lasing

“…Only nonzero matrix element U (2) gives contribution to quadrupole part of energy transfer. If one analyzes the matrix elements of the transitions participated in the cross-relaxational energy transfer from the 4 F 3/2 metastable level of the Nd 3+ ion, namely, ( 4 F 3/2 -4 I 13/2 ; 4 I 9/2 -4 I 15/2 ) and ( 4 F 3/2 -4 I 15/2 ; 4 I 9/2 -4 I 15/2 ) he finds that the matrix element U (2) for all the transitions is equal or close to zero and most contribution to the line strengths of the electronic transitions comes from U (6) and to a lesser extent from U (4) . Hence, only dipole-dipole mechanism of cross-relaxational energy transfer is allowed.…”

“…Among them are an ease of fabrication, low cost, fabrication of large size elements, large concentration and homogeneous distribution of dopants. The R 2 O 2 S was studied recently as fluorescent ceramics [6][7][8][9].…”

Highly transparent ZrO2-doped (Ce,Gd)3Al3Ga2O12 ceramics prepared via oxygen sintering

“…In the past few decades, ceramic scintillators have been well developed for ionizing radiation detection, especially in the X-ray detection and nuclear medical diagnostics [1]. Up to now, three ceramic scintillators have been used in the commercial medical computed tomography (CT) systems [2], among which, Eu:(Y,Gd) 2 O 3 (usually known as HiLight) [3] and Ce:(Lu,Tb) 3 Al 5 O 12 (usually known as Gemstone) [2,4,5] were developed by GE Healthcare; Pr:Gd 2 O 2 Sbased ceramic (GOS) was first developed by researchers of Hitachi Company [6][7][8]. Other CT manufacturers including Siemens [9,10] and Toshiba [11] adopted GOS as its functional material and developed their own proprietary processing technologies.…”

Amorphous silicon position sensitive neutron detector

“…The spatial resolution of the commercially available Gd202S is appreciably higher than NE426. Hitachi co. has also produced a ceramic scintillator made of Gd202S:Pr,Ce,F ... compacked by hot isostatic processing [9], which has been shown to have good properties for X-ray detection. All of these neutron sensitive scintillators have the drawback of containing high Z elements and therefore being gamma sensitive.…”