X-RAY CT APPARATUS AND IMAGE RECONSTRUCTION METHOD

摘要

In order to provide an X-ray CT apparatus and the like, which reconstruct images using an iterative approximation method that converges stably and can be performed at high speed, the computing unit (5) of the X-ray CT apparatus (1) calculates matrices A, B, D, R and R' on the basis of radiography conditions input from the input unit (6) (Step 1). Next, the computing unit (5) calculates each element of the matrix I-a (SB?DA+ßSR) (Step 2). Then, the computing unit (5) calculates the operator norm for the matrix I-a (SB?DA+ßSR) || I-a (SB?DA+ßSR)|| (Step 3). Then, the computing unit (5) determines the relaxation factor a so as to satisfy the prescribed conditional expression (Step 4).