| 摘要 |
<p>The distance (L1), from the central axis (O) of an X-ray tube in the direction perpendicular to the longitudinal direction of a filament coil (15) to the outer side surface of a cathode electron gun (16), is set shorter than the distance (P1) from the central axis (O) of the X-ray tube in the longitudinal direction of the filament coil (15) to the outer side surface of the cathode electron gun (16), and the distance (L2) from the central axis (O) of the X-ray tube in the direction perpendicular to the longitudinal direction of the filament coil (15) to an X-ray radiation window (20a) is set shorter than the distance (P2) from the central axis (O) of the X-ray tube in the longitudinal direction of the filament coil (15) to an X-ray radiation window (20b). With such an arrangement, an optical element for condensing X-rays can be located at a position close to the focal point of the X-ray tube when the X-rays on the line focus side is used, and thereby condensation efficiency of X-rays can be enhanced.</p> |
