X-ray diaphragm mechanism and X-ray CT apparatus

An X-ray diaphragm mechanism, comprising:

• two X-ray shielding members each including an X-ray shielding portion, which is formed of an X-ray shielding material, a first peripheral portion located on one end side of the X-ray shielding portion in a longitudinal direction, and a second peripheral portion located on the other end side of the X-ray shielding portion in the longitudinal direction;
• a first link that connects the first peripheral portions of the X-ray shielding members so that the first peripheral portions cross each other in X-ray incidence direction in a state where the X-ray shielding portions of the X-ray shielding members face each other and a second link that connects the second peripheral portions of the X-ray shielding members so that the second peripheral portions cross each other in the X-ray incidence direction in a state where the X-ray shielding portions of the X-ray shielding members face each other;
• a first connecting portion that connects the first peripheral portion of each X-ray shielding member and the first link to each other and a second connecting portion that connects the second peripheral portion of each X-ray shielding member and the second link to each other;
• and
• a driving device that drives the first link or the second link so as to rotate,
• wherein a slit width between the X-ray shielding portions of the two X-ray shielding members is changed by moving the two X-ray shielding members in conjunction with rotational driving of the first and second links, and the first and second connecting portions are provided at positions not interfering with a movable region of the X-ray shielding member.