光谱法分析代数迭代重建算法及改进

采用光谱分析技术,系列研究了已有代数迭代重建算法,并进一步研制了改进算法一简单自相关代数迭代重建算法(SSART).采用数值模拟的方法模拟重建一个含遮挡物场,研究了SSART模拟效果和重建精度.作为对照,分析了已有的传统代数迭代算法同条件下的重建结果,包括基本代数迭代重建算法(ART)、联合代数迭代重建法(SART)和改进的联合代数迭代重建法(MSART).重建精度用均方误差(MSE),绝对平均误差(AVE)和峰值相对误差(PE)三种误差指数标定.结果发现,SSART重建结果的三种误差指数都明显减小,其中MSE在10-4数量级上比ART的降低了26.6%,PE在10-2数量级降低了77.6%.因此,SSART重建含遮挡物模型场时,重建精度大幅度提高,重建效果明显改善,对传统代数迭代重建算法显著改进.

Algebraic Reconstruction Techniques and Improvement Studied with Spectroscopy

The present article focuses on improving algebraic reconstruction technique(ART) for optical computerized tomography (OCT). With spectroscopy, a series of traditional ARTs were analyzed in detail, then a new improved ART was developed. The new ART was named simple self-correlative algebraic reconstruction technique(SSART). With numerical simulation technique, SSART reconstructing efficiency was demonstrated by reconstructing a simulated field with an opaque object. The simulation result and reconstructing accuracy were analyzed. Many current representative ARTs were studied in order to compare the reconstructing efficiency of the new ART with that of others. These ARTs included basic algebraic reconstruction technique: ART, simultaneous algebraic reconstruction technique: SART, and modified SART: MSART. Each of those was used for reconstructing the same simulated field as that SSART was used to reconstructing. The reconstruction results under the same condition were compared with each other. Reconstruction accuracy of each ART was weighed with three error indexes, mean-square error(MSE) , absolute value error(AVE), and peak error(PE). As the results, each error index of the reconstruction result with SSART declined a lot. The MSE of SSART was decreased about 26.6% compared to that of ART at the level of 10-4 magnitude, and PE 77.6% at the level of 10-2 magnitude. As far as the field with an opaque object is concerned, SSART improves the reconstruction result much, and increases the reconstruction accuracy a lot. SSART improves ARTs greatly.