Acquisition method, acquisition device, and control program for tomographic image data by means of angular offset

A tomographic image data acquisition device comprising:

• a detection device having N detectors arranged in at least one row where N is an integer of 1 or more;
• and
• a controller that controls the detection device so that the detection device detects waves or particles after the waves or particles are transmitted each part of an object disposed in a detection range of the detection device by each of the detectors in a detection direction, wherein the detection direction is changed with respect to the object while irradiation of the waves or particles toward the detection device by an irradiator is performed, or while the waves or particles generated without the irradiator are transmitted through each part of the object and wherein the waves or particles are detectable by the detection device,
• wherein the tomographic image data acquisition device further comprises:
• a discrete inverse Radon transform matrix storage for storing a discrete inverse Radon transform matrix, and
• wherein the controller comprises:
• a discrete Radon transform processor for changing a relative detection direction for the waves or particles viewed from the object and for making the detection device output a detection signal for a sinogram with N rows and N columns, each row and each column of which are associated with each detection direction and each of the detectors, respectively;
• a vectorization processor for obtaining from the detection signal a first vector having N×N elements corresponding to those obtained by vectorizing the sinogram;
• a discrete inverse Radon transform processor for obtaining a second vector having N×N elements by operating the discrete inverse Radon transform matrix to the first vector;
• and
• an image data generator, by de-vectorizing the second vector, for obtaining image data for a two-dimensional tomographic image of N pixels×N pixels having a pixel arrangement in which each pixel is addressed by two-dimensional coordinates where two coordinate axes are defined for the object with a common pitch in vertical and horizontal axes,
• wherein the controller controls the detection device such that the detection device performs detection in each of the detection directions, which is an angle sampling direction corresponding to each angle increment equally dividing an angle scan range into N divisions for reconstructing the two-dimensional tomographic image, and
• wherein one of two directions adjacent to each of two boundaries is offset from one of the coordinate axes and the offset angle is greater than 0° and less than 90° or greater than −90° and less than 0°.

A control program for an acquisition device of tomographic image data, the acquisition device having:

• a detection device having N detectors arranged in at least one row where N is a positive integer, and
• a controller that controls the detection device so that the detection device detects waves or particles after the waves or particles are transmitted each part of an object disposed in a detection range of the detection device for the waves or particles by each of the detectors in a detection direction, wherein relative detection direction for the waves or particles is changed with respect to the object while irradiation of the waves or particles toward the detection device by an irradiator is performed, or while the waves or particles generated without the irradiator are transmitted through each part of the object and wherein the waves or particles are detectable by the detection device,
• wherein the control program makes the controller to perform:
• processing a discrete Radon transform, in which a relative detection direction for the waves or particles viewed from the object is changed, for making the detection device output a detection signal for a sinogram with N rows and N columns, each row and each column of which are associated with each detection direction and each of the detectors, respectively;
• obtaining from the detection signal a first vector having N×N elements corresponding to those obtained by vectorizing the sonogram;
• retrieving a discrete inverse Radon transform matrix from a discrete inverse Radon transform matrix storage and obtaining a second vector having N×N elements by operating the discrete inverse Radon transform matrix to the first vector;
• and
• obtaining image data by de-vectorizing the second vector, for obtaining image data for a two-dimensional tomographic image of N pixels×N pixels having a pixel arrangement in which each pixel is addressed by two-dimensional coordinates where two coordinate axes are defined for the object with a common pitch in vertical and horizontal axes,
• wherein the controller controls the detection device such that the detection device performs detection in each of the detection directions, which is an angle sampling direction corresponding to each angle increment equally dividing an angle scan range into N divisions for reconstructing the two-dimensional tomographic image, and
• wherein one of two directions adjacent to each of two boundaries is offset from one of the coordinate axes and the offset angle is greater than 0° and less than 90° or greater than −90° and less than 0°.