DocumentCode :
1046368
Title :
Light Emission Efficiency of 
(GOS:Eu) Powder Screens Under X-Ray Mammography Conditions
Author :
Michail, Christos M. ; Valais, Ioannis G. ; Toutountzis, Adrianos E. ; Kalyvas, Nektarios E. ; Fountos, George P. ; David, Stratos L. ; Kandarakis, Ioannis S. ; Panayiotakis, George S.
Author_Institution :
Dept. of Med. Phys., Univ. of Patras, Patras
Volume :
55
Issue :
6
fYear :
2008
Firstpage :
3703
Lastpage :
3709
Abstract :
The aim of this study was to examine Gd2O2S:Eu (also known as GOS:Eu) powder scintillator under X-ray mammography imaging conditions. For this purpose, three scintillator screens with coating thicknesses of 33.1, 46.4 and 63.1 mg/cm2 were prepared in our laboratory by sedimentation of Gd2O2S:Eu powder. Light emission efficiency and optical emission spectra of the screens were measured under X-ray excitation using X-ray tube voltages (22-49 kVp) employed in mammography. Spectral compatibility with various optical photon detectors (photodiodes, photocathodes, charge coupled devices, films) and intrinsic conversion efficiency value (0.12) were determined by using emission spectrum data. In addition, parameters related to X-ray detection and energy absorption efficiency were calculated. Gd2O2S:Eu showed peak emission in the wavelength range 620-630 nm. The 63.1 mg/cm2 phosphor screen appeared with the maximum light emission efficiency. Due to its reddish emission spectrum, Gd2O2S:Eu showed excellent compatibility with the sensitivity of many currently used photodetectors and could be considered for application in X-ray imaging especially in various digital detectors.
Keywords :
X-ray detection; X-ray imaging; europium; gadolinium compounds; mammography; nuclear electronics; phosphors; photocathodes; photodetectors; photodiodes; photoluminescence; solid scintillation detectors; GOS:Eu powder scintillator; Gd2O2S:Eu; X-ray detection; X-ray excitation; X-ray imaging; X-ray mammography; X-ray tube; charge coupled devices; digital detectors; films; light emission efficiency; optical photon detectors; phosphor screen; photocathodes; photodetectors; photodiodes; powder scintillator screens; reddish optical emission spectra; voltage 22 kV to 49 kV; wavelength 620 nm to 630 nm; Coatings; Laboratories; Mammography; Optical films; Optical imaging; Optical sensors; Powders; Stimulated emission; X-ray detection; X-ray imaging; ${rm Gd}_{2} {rm O} _{2}{rm S}!!:!!{rm Eu}$ ; luminescence efficiency; matching factor powder phosphors;
fLanguage :
English
Journal_Title :
Nuclear Science, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9499
Type :
jour
DOI :
10.1109/TNS.2008.2007562
Filename :
4723824
Link To Document :
