Digital radiography continues to grow in use in both medical and industrial applications. However, the methods of
characterizing the detectors seem to differ between the two fields. In medical imaging, it is important to achieve the highest
possible contrast and the desired resolution with the lowest possible dose. As a result, the detector quantum efficiency (DQE)
defines the detector performance. Industrial radiography often strives for characterization of the system’s ability to detect
a feature through stacking of material. For industrial radiography this results in the use of line pair gauges, penetrometers,
and other image quality indicators (IQIs) as the standard measurement of performance and capability. This paper presents
the relationship between DQE, noise power spectrum (NPS), and modulation transfer function (MTF) typically used to
characterize medical imaging detectors and will form the foundation of how this information can be used to predict a detector
and source’s ability to resolve penetrometer features through a combination of measurements and calculations. This work was
performed using a Varian 2530HE (new high energy panel), and NX1 (new 0.95 MV accelerator).
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