Patent ID: 7440547

Claim:
A CT scanner which collects X-ray projection data of a subject and which generates an image of the subject from the projection data, the CT scanner comprising: first to third X-ray tubes which emit X-rays and which include grids to switch emission and stoppage of the X-rays; a high-voltage generation unit which generates a high voltage to be supplied to the first to third X-ray tubes; a high-voltage cable which sends the high voltage to each of the first to third X-ray tubes, the high-voltage cable connecting the high-voltage generation unit to the first X-ray tube, the second X-ray tube, and the third X-ray tube; a plurality of grid control circuits which change potentials of the grids and are arranged near the first to third X-ray tubes, respectively, and include semiconductor switches; a control unit which controls the grid control circuits to switch the emission and the stoppage of the X-rays in a pulse manner while the first to third X-ray tubes rotate around the subject; and a plurality of X-ray detectors arranged to face the first to third X-ray tubes, respectively.