Abstract: A method and system for determining a location of artefacts and/or inclusions in a gemstone, mineral or sample thereof, the method comprising: surface mapping a gemstone, mineral or sample thereof to determine surface geometry associated with at least a portion of a surface of the gemstone, mineral or sample thereof; sub-surface mapping the gemstone, mineral or sample thereof using an optical beam that is directed at the surface along an optical beam path, wherein the optical beam is generated by an optical source using an optical tomography process; determining a surface normal at the surface at an intersection point between the optical beam path and the determined surface geometry; determining relative positioning between the surface normal and the optical beam path; and determining the location of artefacts and/or inclusions in the gemstone, mineral or sample thereof based on the sub-surface mapping step and the determined relative positioning.

Abstract: A method and system for determining a location of artefacts and/or inclusions in a gemstone, mineral or sample thereof, the method comprising the steps of: surface mapping a gemstone, mineral or sample thereof to determine surface geometry associated with at least a portion of a surface of the gemstone, mineral or sample thereof; sub-surface mapping the gemstone, mineral or sample thereof using an optical beam that is directed at the surface along an optical beam path, wherein the optical beam is generated by an optical source using an optical tomography process; determining a surface normal at the surface at an intersection point between the optical beam path and the determined surface geometry; determining relative positioning between the surface normal and the optical beam path; and determining the location of artefacts and/or inclusions in the gemstone, mineral or sample thereof based on the sub-surface mapping step and the determined relative positioning.

Abstract: A method and system for determining a location of artefacts and/or inclusions in a gemstone, mineral or sample thereof, the method comprising the steps of: surface mapping a gemstone, mineral or sample thereof to determine surface geometry associated with at least a portion of a surface of the gemstone, mineral or sample thereof; sub-surface mapping the gemstone, mineral or sample thereof using an optical beam that is directed at the surface along an optical beam path, wherein the optical beam is generated by an optical source using an optical tomography process; determining a surface normal at the surface at an intersection point between the optical beam path and the determined surface geometry; determining relative positioning between the surface normal and the optical beam path; and determining the location of artefacts and/or inclusions in the gemstone, mineral or sample thereof based on the sub-surface mapping step and the determined relative positioning.

Abstract: Some embodiments of the invention provide a method of determining a material characteristic of material in a sample by iterative tomographic reconstruction. The method conducts one or more X-ray tomography scans of a sample, and then determines one or more estimated material characteristics, such as atomic number and density, for multiple volume elements in the sample using a tomographic reconstruction algorithm. These estimated material characteristics are then modified by reference to stored known material characteristic data. Preferably, determining the composition of the sample volume during reconstruction includes segmenting the sample into regions of common composition, the segmenting being performed during iterative reconstruction instead of being based on the voxel characteristics determined upon the completion of iterative reconstruction.

Abstract: A method for processing image data of a sample is disclosed. The method comprises registering a first and a second images of at least partially overlapping spatial regions of the sample and processing data from the registered images to obtain integrated image data comprising information about the sample, said information being additional to that available from said first and second images.

Abstract: Some embodiments of the invention provide a method of determining a material characteristic of material in a sample by iterative tomographic reconstruction. The method conducts one or more X-ray tomography scans of a sample, and then determines one or more estimated material characteristics, such as atomic number and density, for multiple volume elements in the sample using a tomographic reconstruction algorithm. These estimated material characteristics are then modified by reference to stored known material characteristic data. Preferably, determining the composition of the sample volume during reconstruction includes segmenting the sample into regions of common composition, the segmenting being performed during iterative reconstruction instead of being based on the voxel characteristics determined upon the completion of iterative reconstruction.

Abstract: A method for processing image data of a sample is disclosed. The method comprises registering a first and a second images of at least partially overlapping spatial regions of the sample and processing data from the registered images to obtain integrated image data comprising information about the sample, said information being additional to that available from said first and second images.

Abstract: A computed tomography imaging process, including: accessing projection data representing two-dimensional projection images of an object acquired using a misaligned tomographic imaging apparatus; and processing the projection data to generate misalignment data representing one or more values that quantify respective misalignments of the tomographic imaging apparatus.

Abstract: A method for processing image data of a sample is disclosed. The method comprises registering a first and a second images of at least partially overlapping spatial regions of the sample and processing data from the registered images to obtain integrated image data comprising information about the sample, said information being additional to that available from said first and second images.

Abstract: A computed tomography imaging process, including: accessing projection data representing two-dimensional projection images of an object acquired using a misaligned tomographic imaging apparatus; and processing the projection data to generate misalignment data representing one or more values that quantify respective misalignments of the tomographic imaging apparatus.

Abstract: A method for processing image data of a sample is disclosed. The method comprises registering a first and a second images of at least partially overlapping spatial regions of the sample and processing data from the registered images to obtain integrated image data comprising information about the sample, said information being additional to that available from said first and second images.