| 摘要 |
PURPOSE:To obtain a rotary anode X-ray tube with a cathode structure capable of getting multi-focal points without rotating an X-ray tube by inclining a holder holding focusing bodies. CONSTITUTION:A cathode is constituted so that focusing bodies 3b, 3c having filaments 5c, 5d, 5e, 5f with different focal sizes respectively are held by a holder 4a. The holder 4a is inclined to angles alpha, beta so that the electrons from individual filaments of the focusing bodies 3b, 3c hit the same position C' on a target surface 2. Four or more focal points can be selected only by means of the lighting operation of filaments, thus contributing to the improvement of the picture quality. |
