Patent ID: 7679065

Claim:
A method for processing transmission data from neutron and gamma-ray radiation to form an image of an object's contents, the neutron and gamma-ray radiation having traversed through the object and representing a measure of neutron attenuation and gamma-ray attenuation introduced by the object, the method comprising: forming a neutron mass attenuation matrix n from the measure of neutron attenuation; forming a gamma-ray mass attenuation matrix g from the measure of gamma-ray attenuation; calculating a composition matrix R whose elements R ij are defined as a function of the elements n ij from the neutron mass attenuation matrix and the corresponding elements g ij from the gamma-ray mass attenuation matrix, the composition matrix representing an average composition of material within the object between a source which generated the radiation and a point (i,j); calculating a density matrix X whose elements X ij are defined as a function of the elements n ij from the neutron mass attenuation matrix and the corresponding elements g ij from the gamma-ray mass attenuation matrix, the density matrix representing an approximate amount of material within the object between the radiation source and the point (i,j); calculating a quality matrix Q whose elements Q ij are defined as a function of the elements n ij from the neutron mass attenuation matrix and the elements g ij of the gamma-ray mass attenuation matrix, the quality matrix representing a measure of the reliability of the determination of the elements of R ij ; and forming an image of the contents of the object for display; wherein the image contains information from R, X, and Q.