THE FOURTH GENERATION SPIRAL SCANNING METHOD

摘要

PURPOSE: To lessen the skew arch fact of the data acquired in spiral form by interpolating or extrapolating the obtained projection set in which the spiral offset from two sensor vs. crest semi-scans acquired near the slice plane is lessened. CONSTITUTION: The slice plane 14 for an imaging object 12 parallel with the image plane is confirmed. Then the data about the beam source 10 vs. crest projection set is acquired over a rotation of the beam source 10 for 2π. The object 12 is moved along the Z-axis and the beam source 10 is rotated so that the imaging plane intercepts the slice plane 14 during acquisition of the beam source 10 vs. crest projection set. The obtained set is re-inserted to the sensor 18 vs. crest projection set. This sensor vs. crest projection set is divided into two semi-scans, and the data is jointed between the semi-scans so that the perfect sensor vs. crest projection set for 2π is prepared. Further the semi-scan data is extrapolated or interpolated to generate the sensor vs. crest projection set for the slice plane, and the obtained set is restructued to produce the intended slice image.