| 主权项 |
1. An X-ray imaging system, comprising: a radiation generating apparatus which includes an X-ray generating unit configured to emit X-ray from a target upon irradiation with an electron beam, and a movable diaphragm unit which includes a restricting blade configured to restrict a passage range of the X-ray and a moving mechanism of the restricting blade; and
an X-ray detecting device configured to detect, on a detector plane, X-ray emitted from the radiation generating apparatus and has passed through an object, wherein the restricting blade has a predetermined thickness defined by a front surface on a target side and back surface of the opposite side of the front surface, and includes an end surface which communicates with the front surface and the back surface on a side on which the X-ray passes, the moving mechanism moves the restricting blade in a direction in which the restricting blade crosses the end surface, wherein, when a width of an eclipsed penumbra formed by X-ray emitted from a focal spot defined by an electron beam flux applied to the target, is in contact with the end surface, and arrives at a first virtual plane which includes the detector plane is denoted by h1 and a width of an attenuated penumbra formed by X-ray emitted from the focal spot, enters from the end surface, passes through the restricting blade, and arrives at the first virtual plane is denoted by h2, a relationship h2<h1 is satisfied, a second virtual plane which is in contact with the end surface crosses a third virtual plane which includes the focal spot, when the restricting blade is moved away from a normal line extending from a center of the focal spot to the first virtual plane, a moving distance of a crossing line of the second virtual plane and a third virtual plane with respect to a center of the focal spot is shorter than a moving distance of the end surface with respect to the normal line. |
