Process and apparatus for the reconstruction of three-dimensional images of an object using two circular acquisition paths

Claim 1

A process for reconstructing a three-dimensional image of an object, comprising the steps of: using at least one two-dimensional array of sensors for acquiring at least two measurement sets of a function at selected points of the object defined by coordinates in an object reference frame, said function, which represents the image of the object, being a property of a radiation viewed by said sensors, wherein the at least one array travels along at least two circular trajectories around the object, the sensors of each of said at least one array of sensors being focused to a respective common focal point beyond the object and at a constant position with respect to said sensors so that each focal point travels along a respective circular focal trajectory and said sensors view a conical space and one trajectory reference frame and one of the measurement sets being associated with each of the focal trajectories; reconstructing the image of the object from the measurement sets of the image, said image reconstruction including the steps of: computing for each of the measurement sets, sums of the function over planes (P) of a respective plane set of a plane domain, wherein the planes of the respective plane set are defined by coordinates in the trajectory reference frame associated with the measurement step, the planes of the respective plane set crossing the focal trajectory to which the measurement set is associated and including at least one point of the object, so as to get as many sums as said planes; merging in an object reference frame the sums provided in the measurement sets in computing, for each of the planes of the plane domain, coordinates defining said plane; and inverting the merged sums in the object reference frame in order to get the reconstructed image of the object.