Patent ID: 7263169

Claim:
An x-ray computed tomography apparatus comprising: a rotary frame rotatable around a system axis; an x-ray source and a radiation detector mounted opposite each other on said rotary frame, said x-ray source emitting an x-ray beam propagating toward said radiation detector; and a radiation diaphragm disposed in a path of said x-ray beam for gating said x-ray beam into a fan-shaped beam, having a selectable size, on said radiation detector, said diaphragm comprising movable gating elements, each movable gating element comprising a radiation absorber element having opposite ends defining an absorber element length therebetween substantially perpendicular to said system axis; and a carrier mounted in said diaphragm for movement in a direction along said system axis, and a clamping device that fixedly clamps the absorber element to the carrier at two points spaced from said ends and spaced from each other along said absorber element length.