Abstract: A controller of the cross sectional area and shape of an X-ray beam includes two or more disks disposed in the center of the path of the beam, each disk being radio-opaque except for a window centered on the beam. One or more of the disks has a tracks at each side of the window in which shutters can slide between positions in which they close or open the window and select the size and shape of the X-ray beam passed through the controller and a subject to an image intensifier or other X-ray utilization device. One of the disks has a cam track which is engaged by a cam following element attached to a shutter on the other disk. The disks are mounted for relative rotation by drive motors which causes the shutter with the cam follower to change position and alter the size or shape of the transmitted beam cross section. With the shutter in desired position the disks can be rotated together to reorient the shaped beam around its central axis.

Abstract: X-ray apparatus comprises a U-shaped support having two hollow, horizontal arms. On the end of one arm is mounted an X-ray tube and on the other an X-radiation receptor both guided for movement on a radiation axis.A counterweight within one hollow, horizontal arm is guided for movement parallel to the X-ray tube, transversely of the arm. To counterbalance the X-ray tube a lever attached to the tube has sliding pivots at a fulcrum and the counterweight allowing the lever arm to change its length without changing the leverage ratio.