Abstract: In an upright CT scanner, an X-ray source and a two-dimensional digital X-ray detector are mounted on a rotating platform with a vertical axis of rotation. During scanning, the X-ray source and the detector are on opposite sides of the rotational axis for orbiting about a body to thereby scan it with pyramid-shaped X-ray beam. During scanning, the source and detector can be jointly translated along a horizontal axis that is perpendicular to the rotation axis and parallel to the detector surface, to scan a specific part of a body that is not centered or a body that is too large. The mounting height and distance of source and the detector can also be adjusted.