| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotary X-ray tube which can be turned on and turned off at fast speed. SOLUTION: This rotary X-ray tube 10 is provided with a cathode assembly containing a cathode and a cathode current source 18 and an anode assembly having an anode 24 whose electric current is controlled by the cathode current source 18. A filament 12 to emit an electron is separated from the cathode, and a cathode cap 28 supports the filament 12, and helps shape an electron field. The X-ray tube 10 also has distributive capacitance to exert influence on the electron field of the cathode cap 28 and an insulator leakage resistance 32. The cathode cap 28 can float on the insulator leakage resistance 32, and therefore, voltage caused by the distributive capacitance and the leakage resistance can be kept comparatively constant. |
