Detective quantum efficiency (DQE) of high X-ray absorption Lu_2O_3:Eu thin screens: the role of shape and size of nano- and micro-grains

摘要

The study concerned with the current work is to provide a comparative investigation of the detective quantum efficiency (DQE) of Lu~(2)O~(3):Eu phosphor screens, prepared with different grain shape/size grains, specifically spherical grains, with sizes 50 nm, 200 nm, and 5 µm and two screens with rod-like shape grains and sizes 500 nm and 1–8 µm. The phosphors were deposited by the sedimentation method. It was found that the influence of the grains shape on image quality is more important than the grain size. The rod-like grains show higher noise levels, at low frequencies. The influence of grains size, between 50 nm, 200 nm, and 5 µm, is negligible on the normalize noise power spectrum (NNPS) at higher spatial frequencies due to structural non-uniformities. The spherical grains exhibited higher DQE values.