X-RAY TUBE ARRANGEMENT WITH TOROIDAL ROTATABLE FILTER ARRANGEMENT AND COMPUTED TOMOGRAPHY DEVICE COMPRISING SAME

摘要

An X-ray tube arrangement (120) for dual energy operation is proposed. The arrangement comprises an electron source (210) for emitting an electron beam (215) and a disk-shaped anode (230). Furthermore, a rotatable filter arrangement (125) is provided comprising a toroidal filter (126) with a filter pattern comprising an X-ray absorption portion arranged along a circumference of the toroidal filter (126). The rotatable filter arrangement (125) is adapted to rotate the toroidal filter around a rotation axis (237) orthogonal to the disk-shaped anode (230). The filter arrangement (125) may be attached to the tube housing (122) such that the toroidal filter (126) is held by a bearing (124). Alternatively, the toroidal filter (126) may be attached to the anode (230). Gyroscopic forces resulting upon filter (126) rotation may be reduced especially when applied in a rotating gantry of a CT device.