Luminescence Efficiency of Cadmium Tungstate (CdWO<sub>4</sub>) Single Crystal for Medical Imaging Applications

Christos Michail; Vaia Koukou; Niki Martini; George Saatsakis; Nektarios Kalyvas; Athanasios Bakas; Ioannis Kandarakis; George Fountos; George Panayiotakis; Ioannis Valais

doi:10.3390/cryst10060429

Crystals (May 2020)

Luminescence Efficiency of Cadmium Tungstate (CdWO<sub>4</sub>) Single Crystal for Medical Imaging Applications

Christos Michail,
Vaia Koukou,
Niki Martini,
George Saatsakis,
Nektarios Kalyvas,
Athanasios Bakas,
Ioannis Kandarakis,
George Fountos,
George Panayiotakis,
Ioannis Valais

Affiliations

Christos Michail: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
Vaia Koukou: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
Niki Martini: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
George Saatsakis: Department of Medical Physics, Faculty of Medicine, University of Patras, GR-15310 Rion, Greece
Nektarios Kalyvas: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
Athanasios Bakas: Department of Biomedical Sciences, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
Ioannis Kandarakis: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
George Fountos: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece
George Panayiotakis: Department of Medical Physics, Faculty of Medicine, University of Patras, GR-15310 Rion, Greece
Ioannis Valais: Department of Biomedical Engineering, Radiation Physics, Materials Technology and Biomedical Imaging Laboratory, University of West Attica, Ag. Spyridonos, 12210 Athens, Greece

DOI: https://doi.org/10.3390/cryst10060429
Journal volume & issue: Vol. 10, no. 6
p. 429

Abstract

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Background: In this study, the light output of a cadmium tungstate (CdWO4) single crystal was measured under various X-ray radiographic energies. Methods: A CdWO4 single crystal (10 × 10 × 10 mm3) was exposed to X-rays in the 50–130 kVp range. Measurements were evaluated against published data for single crystals of equal dimensions (CaF2:Eu and Lu3Al5O12:Ce). Since the crystal was examined for application in medical imaging detectors, the emitted optical spectrum was classified with respect to the spectral compatibility of numerous commercial optical sensors. Results: The luminescence efficiency (LE) was found to constantly increase with X-ray energy and was higher than that of CaF2:Eu for energies above 90 kVp. However, the efficiency of the previously published Lu3Al5O12:Ce was found to be constantly higher than that of CdWO4. The light emitted from CdWO4 can be optimally detected by certain charge-coupled devices (CCDs), amorphous silicon photodiodes, and photocathodes. Conclusions: The high density (7.9 g/cm3) of CdWO4 and the luminescence signal of this material make it suitable for medical imaging (such as dual energy), high-energy physics or for applications of scintillators in harsh environments.

Published in Crystals

ISSN: 2073-4352 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Science: Chemistry: Crystallography
Website: http://www.mdpi.com/journal/crystals/

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