PROBLEM TO BE SOLVED: To improve controllability of X-ray generation in a triode X-ray tube.SOLUTION: This X-ray computed tomography apparatus includes: an X-ray tube 121 having a negative electrode 124, a positive electrode 122, and a bias electrode 125 an X-ray detector 14 an image reconstruction part 23 a high voltage power supply 131 generating a tube voltage a filament heating power supply 132 a bias power supply 133 and an X-ray control part 16 controlling the high voltage power supply, the filament power supply, and the bias power supply. The X-ray control part makes the tube voltage be continuously applied, makes a filament current be continuously supplied, makes a bias voltage be applied as a pulse train, and varies at least one of a pulse repetition frequency and a pulse width of the bias voltage with time.COPYRIGHT: (C)2013,JPO&INPIT【課題】 三極X線管におけるX線発生の制御性を向上すること。【解決手段】X線コンピュータ断層撮影装置は、陰極124と、陽極122と、バイアス電極125とを有するX線管121と、X線検出器14と、画像再構成部23と、管電圧を発生する高電圧電源131と、フィラメント加熱電源132と、バイアス電源133と、高電圧電源とフィラメント加熱電源とバイアス電源とを制御するX線制御部16とを具備し、X線制御部は、管電圧を継続的に印加させ、フィラメント電流を継続的に供給させ、バイアス電圧をパルス列として印加させるとともに、バイアス電圧のパルス幅とパルス繰り返し周波数との少なくとも一方を経時的に変化させる。【選択図】 図2
