Wide view-field three-D CT imaging method

Abstract

The large field of view three-dimensional CT imaging method, the steps are: (1) perform the first single circular orbit cone beam CT scan to obtain the first set of digital ray projection image sequences; distance, conduct the second single circular orbit cone beam CT scan to obtain the second set of digital ray projection image sequences; (3) perform dark current and inconsistency correction on the two sets of digital ray projection images; (4) record the ray source to the detector (5) According to the above-mentioned parameters, utilize the projection rearrangement algorithm researched by the present invention to rearrange the above-mentioned incomplete two groups of cone-beam ray projection digital image sequences into complete (6) according to the image sequence obtained in step (5), utilize the parallel beam ray reconstruction algorithm studied in the present invention to reconstruct the three-dimensional CT image of the scanning area. The present invention can expand the imaging field of view of the single-circle-orbit cone-beam scanning to 3 times the original through two single-circle-orbit cone-beam scans on the inspection table, and the scanning and reconstruction process is simple and efficient.

Description

Technical field [0001] The invention relates to a three-dimensional CT imaging method with a large field of view, belonging to the technical field of X-ray CT. Background technique [0002] In the X-ray CT system, the X-ray source emits X-rays, passes through a certain area of ​​the object to be inspected from different angles, and the detector placed opposite the ray source receives it at the corresponding angle, and then the rays are attenuated in different degrees according to each angle. A certain reconstruction algorithm and computer are used to perform calculations to reconstruct the ray attenuation coefficient distribution mapping image of the scanned area of ​​the object, so as to realize the reconstruction of the image by projection, and losslessly reproduce the characteristics of the object’s medium density, composition and structure in the area. . [0003] In the existing typical cone-beam ray 3D-CT imaging, in order to meet the complete conditions of Tuy, Smith and Gr...

AI Technical Summary

Problems solved by technology

[0005] The technical solution of the present invention is to provide a three-dimensional CT imaging with a large field of view based on two offset scans of the inspection table for the problem of a small scanning field of view in the current three-dimensional CT based on single circular orbit cone beam scanning and FDK reconstruction algorithm method, to solve the fast three-dimensional tomography of larger-sized components and the high-magnification ratio micro-tomography of small specimens. Through two single-circle-orbit cone-beam scanning and quasi-parallel-beam rearrangement processing on the inspection table, the single-circle-orbit cone-beam The scanning imaging field of view is expanded to 3 times of the original, and the scanning and reconstruction process is simple and efficient

Images