Optical tomography imaging is widely used in target-detection, aerospace precision instrumentation and geological material detection for its non-contact, long-distance and high-precision imaging characteristics. Due to the different application range and structural design of the tomography system, the inevitable inadequate projection data and the offset of the rotation center may occur in the actual acquisition, which may cause artifacts and unclearness in the reconstructed image. In this paper, based on the research of image reconstruction algorithm, the paper compares filter back projection algorithm with iterative algorithm and analyzes effects of the reconstruction process with iterative algorithm under multiple parameters. Determining the appropriate weighting model, iteration number and relaxation factor, etc. Combined with high quality initial image and convex set constraints, an optimized SART algorithm is proposed. The experiment uses the optimized SART algorithm for image reconstruction. By comparing the image evaluation parameters with sharpness and average gradient, it is verified that the construction image with the optimized SART is better and clearer than those with the unoptimized SART and the simple filtered back projection algorithm.
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