Patent ID: 7215732
Filing Date: 2007-05-08
Classification: G06T

Abstract:
1. A method for reconstructing image data from measured sinogram data acquired from a Computed Tomography (CT) system, the method comprising: pre-processing the measured sinogram data, wherein the pre-processing comprises performing a beam hardening correction on the measured sinogram data and performing a detector point spread function (PSF) correction and a detector lag correction on the measured sinogram data; and reconstructing the pre-processed sinogram data to generate the image data, wherein the CT system is configured for industrial imaging, wherein performing the beam hardening correction on the measured sinogram data comprises: computing a detector efficiency curve associated with the CT system, scaling an X-ray source spectrum by the detector efficiency curve to obtain a corrected X-ray source spectrum, determining an attenuation coefficient value for each material traversed by at least one X-ray, at one or more X-ray energy levels, and analytically deriving a beam hardening correction curve based on the attenuation coefficient value at the one or more X-ray energy levels and the corrected X-ray source spectrum.