28 June 2001 Modeling the x-ray energy characteristics of DQE for full-field digital mammography
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The modulation transfer function and detective quantum efficiency are modeled for a Full Field Digital Mammography detector constructed with a CsI scintillator deposited on an amorphous silicon active matrix array. The model is evaluated against experimental measurements using different exposure levels, x-ray tube voltages, target composition and beam filtrations as well as varying thicknesses and compositions of filtration materials placed in the path between the tube and detector. Available x-ray tube emission spectrum models were evaluated by comparison against the measured transmission through aluminum. The observed variation of DQE at zero spatial frequency among different target/filter conditions, acrylic filtration thicknesses and kVp is well characterized by a x-ray model. This variation is largely accounted for by just two effects -- the attenuation of x-rays through the detector enclosure and the stopping power of x-rays in the CsI layer. Additional considerations such as the Lubberts effect were included in the analysis in order to match the measured DQE(k) as a function of spatial frequency, k. The pixel aperture and light channeling through the scintillator shape the MTF which acts favorably to avoid aliasing due to digital sampling.
© (2001) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
J. Eric Tkaczyk, J. Eric Tkaczyk, James W. LeBlanc, James W. LeBlanc, Robert L. Nevin, Robert L. Nevin, Gregory M. Kautz, Gregory M. Kautz, Douglas Albagli, Douglas Albagli, John M. Sandrik, John M. Sandrik, Paul R. Granfors, Paul R. Granfors, } "Modeling the x-ray energy characteristics of DQE for full-field digital mammography", Proc. SPIE 4320, Medical Imaging 2001: Physics of Medical Imaging, (28 June 2001); doi: 10.1117/12.430883; https://doi.org/10.1117/12.430883

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