X-Ray Detector Characterization - a comparison of scintillators

In this Master thesis work, four different indirect x-ray detector setups have been compared in terms of resolution, noise and overall performance at different x-ray photon energies; one camera from Photonic Science with a 15 μm thick Gadox scintillator and one camera from Princeton Instruments used together with one 48 μm thick Gadox scintillator, one 370 μm thick needle grown CsI scintillator and one 170 μm thick CsI-based structured scintillator from a company called Scint-X. Primarily, the modulation-transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) were measured for all detectors. The MTF was measured by imaging a sharp edge, the NPS was measured from flat-field images and the DQE was calculated as a function of these two quantities. Simulations were also done in order to compare the detectors at arbitrary energies. The measurements showed that the detector with a thin Gadox scintillator had both the highest resolution and the best overall performance at low energies. At high energies, the CsI-based scintillators performed best and the one from the company Scint-X had highest resolution.