| 摘要 |
PROBLEM TO BE SOLVED: To provide a rotary anode X-ray tube in which the focal position of an X-ray can be changed by simple circuitry.SOLUTION: The rotary anode X-ray tube includes a cathode having a filament for discharging thermions and a focus electrode for focusing the thermions from the filament, and an anode having an anode target 6 disposed to face the cathode. The filament includes at least two filaments 3a, 3b, arranged to stagger in the length direction, and a changeover section 14 supplies power for discharging thermions to one of the staggered filaments 3a, 3b while switching. |
