A nonuniform detector aperture for CT

The finite width of the X-ray beam determined by the source and detector aperture limits the resolution of computed tomography (CT) images. Improved resolution can be obtained by reducing the width of the detector, but at a cost in dose utilization efficiency. We show that it is possible to improve the resolution in a CT image with a minimum cost in dose efficiency by varying the sensitivity of (apodizing) the detector response function. Further, we demonstrate how to construct detectors with nonuniform response by changing the reflective coating on the scintillator. Finally, we show improved calculated point response functions for such modified detectors.