MTF of columnar phosphors with a homogenous part: an analytical approach

Medical & Biological Engineering & Computing - Tập 58 - Trang 2551-2565 - 2020
Konstantinos Psichis1, Nektarios Kalyvas2, Ioannis Kandarakis2, George Panayiotakis1
1Department of Medical Physics, School of Medicine, University of Patras, Patras, Greece
2Department of Biomedical Engineering, University of West Attica Athens, Greece

Tóm tắt

A method for the theoretical estimation of the MTF of columnar phosphors with a homogeneous part at the end used in X-ray imaging has been developed. This method considers the light transport inside the scintillator through an analytical modelling, the optical photon beams distribution on the scintillator–optical sensor interface, and uses the definition of the PSF and a Gauss fitted LSF to estimate the MTF of an indirect detector. This method was applied to a columnar CsI:Tl scintillator and validated against experimental results found in literature, and a good agreement was observed. It was found that, by increasing the pixel size of the optical detector and the thickness of the scintillator, the MTF decreased as expected. This method may be used in evaluating the performance of the columnar phosphors used in medical imaging, given their physical and geometrical characteristics. Graphical abstract

Tài liệu tham khảo

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