| 摘要 |
X-ray imaging method, in which the data (c(a), rho(b)) are processed by a programmed computer using the following formula: C = rho ( b ) n + c ( a ) n - 1 2 n 2 (∑k = 1 n c k ( a ) +∑u = 1 n rho u ( b ) ) to calculate a value (C) of the attenuation coefficient at a point (P0) of a set of points {P0}, for a given pair of said angular positions thetaa and thetab, in order to obtain an image representing an X-ray attenuation coefficient for said set of points {P0} of the body (3). According to the invention, the computer is programmed to perform the following stages: (1) pre-calculate the positions on the detector (9) of a first impact point T(a) of a ray i and a second impact point R(b) of a ray j, (2) pre-calculate the positions on the detector of first and second load calculation lines, along detection points Tp,k; k=1->n; p=1->m and Rq,u; u=1->n; q=1->m, and (3) calculate the value of the attenuation coefficient at point P0 in the volume irradiated by using the pre-calculated positions of the first and second impact points T(a); R(b) and the pre-calculated first p and second q load calculation lines Tp,k(a); k=1->n; Rq,u(b); u=1->n that pass closest to the first and second impact points (T(a); R(b)) respectively.
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