Evaluating phosphors for use in X-ray image detectors by the effective performance index (EPI) method: application to Eu³⁺ activated yttrium based materials

Article type: Research Article

Authors: Cavouras, D.^{a; *} | Kandarakis, I.^a | Prassopoulos, P.^b | Kanellopoulos, E.^a | Nomicos, C.D.^c | Panayiotakis, G.S.^d

Affiliations: [a] Department of Medical Instrumentation Technology, Technological Educational Institution of Athens, Ag. Spyridonos Street, Aigaleo, 122 10 Athens, Greece | [b] Department of Radiology, University Hospital, Medical School, University of Crete, Heraklion, Greece | [c] Department of Electronics, Technological Educational Institution of Athens, Ag. Spyridonos Street, Aigaleo, 122 10 Athens, Greece | [d] Department of Medical Physics, Medical School, University of Patras, 265 00 Patras, Greece

Correspondence: [*] Please address correspondence: Prof. D. Cavouras, Ph.D., 37-39 Esperidon Street, Kallithea 17671, Athens, Greece. Tel.: (+301) 9594 558; Fax: (+301) 5910 975; E-mail: [email protected].

Abstract: Phosphor materials used in X-ray image receptors were evaluated by the effective performance index (EPI). EPI describes the dependence of image quality on X-ray to light energy conversion and light diffusion processes. EPI was experimentally determined by means of X-ray luminescence (XLE) and MTF measurements performed on Y2O2S:Eu, Y2O3:Eu, and YVO4:Eu phosphors. The spectral compatibility of these materials with optical detectors (films, photocathodes, photodiodes) was also determined. Highest EPI values were obtained for Y2O2S:Eu-GaAs combination at mammographic energies. All phosphors could be of use in digital X-ray imaging being adequately compatible to silicon photodiodes employed in digital detectors.

Keywords: Phosphors, X-ray image detectors, X-ray luminescence, MTF

DOI: 10.3233/THC-1999-7104

Journal: Technology and Health Care, vol. 7, no. 1, pp. 53-61, 1999