Title :
Thin substrate powder scintillator screens for use in digital X-ray medical imaging applications
Author :
Valais, Ioannis G. ; Fountos, George P. ; Michail, Christos M. ; Seferis, Ioannis ; Kalyvas, Nektarios I. ; Mytafidis, Alexandros K. ; Kandarakis, Ioannis S. ; Panayiotakis, G.S.
Author_Institution :
Dept. of Med. Instrum. Technol., Technol. Educ. Instn. of Athens, Athens, Greece
Abstract :
The aim of the present study is to investigate the absolute luminescence efficiency (AE) and the effective luminescence efficiency (EE) of thin substrate Gd2O2S:Eu powder scintillating screens, for possible use in digital radiography detectors. To this aim two relatively thin screens with thicknesses (coating density) 32.1 mg/cm2 and 64.9 mg/cm2 were prepared on Borosilicate glass substrate 22×22 mm2. For the determination of the AE, X-ray tube voltages ranging from 50 to 133 kVp were used. The effective efficiency was examined for four optical sensors, currently adapted in diagnostic medical systems, namely S100AB SITe, passivated a-Si:H photodiode, CMOS hybrid with blue AR coating and CMOS RadEye photodiode array. The absolute luminescence efficiency of the thin substrate Gd2O2S:Eu powder phosphors was relatively high. The spectral compatibility and the overall efficiency (effective efficiency) with the optical detectors examined in our study was higher than that of a corresponding thickness Gd2O2S:Tb powder phosphors. Our preliminary results indicate that thin substrate Gd2O2S:Eu powder phosphors can be used adequately with detectors for digital X-ray Imaging.
Keywords :
CMOS image sensors; X-ray tubes; borosilicate glasses; diagnostic radiography; elemental semiconductors; europium; gadolinium compounds; hydrogen; luminescence; optical sensors; oxygen compounds; passivation; photodiodes; powders; silicon; solid scintillation detectors; CMOS RadEye photodiode array; Gd2O2S:Eu; S:H; X-ray tube voltages; absolute luminescence efficiency; blue AR coating; coating density; diagnostic medical systems; digital X-ray medical imaging; digital radiography detectors; effective luminescence efficiency; optical detectors; optical sensors; passivated photodiode; powder phosphors; size 22 mm; spectral compatibility; thin substrate powder scintillator screens; CMOS integrated circuits; Electron tubes; Luminescence; Optical fiber sensors; Optical fibers; Phosphors; Stimulated emission;
Conference_Titel :
Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE
Conference_Location :
Valencia
Print_ISBN :
978-1-4673-0118-3
DOI :
10.1109/NSSMIC.2011.6152537
