In this paper , two novel algorithms of reconstructing high resolution images from both overlapped parallel projection data and overlapped fan beam projection data with low resolution are presented . one is called virtual detector algorithm , and the other is direct reconstruction algorithm . both of the algorithms with two forms for the parallel data and fan beam data respectively are developed based on the interpolative algebraic reconstruction techniques ( iart ) 本文在研究插值代數(shù)重建法( iart )的基礎上,根據(jù)特別設計的數(shù)據(jù)采集模式(平行相疊采樣和扇形相疊采樣) ,提出了由相疊低分辨數(shù)據(jù)重建高分辨圖像的兩個新算法,即虛擬探測器法和直接重建法。