Abstract: The invention relates to X-ray tubes, and more particularly to cathodes for such tubes. The invention lies in the cathode, which includes an electron-emitting filament (26), being made in the form of a main body (10) of insulating material having metal electrodes (16 and 19) deposited thereon which are insulated from one another by the main body. The filament (26) and the electrodes (16 to 19) are connected to conductors (27, 21 to 23) which pass through the main body.

Abstract: A radiological device is provided of the type comprising a radiogenic tube with magnetic bearings, said radiogenic tube being contained in a sheath as well as electronic means for controlling said magnetic bearings.

Abstract: An equipped forced-convection housing unit for a rotating-anode X-ray tube comprises a flow-initiating device which is integrated in the housing unit and has the function of circulating the coolant fluid surrounding the X-ray tube. This arrangement simplifies the problems relating to supply of electric power to the motor which drives the flow-initiating device and the motor which drives the anode of the X-ray tube in rotation.

Abstract: The present invention concerns an X-ray examination apparatus allowing to produce images of an object through the scanning of the object by at least two fan-shaped beams having different energy spectra, and obtained from a single X-ray source, thereby allowing to obtain simultaneously images of the object adapted to contain different informations.

Abstract: The invention relates to an X-ray apparatus with focus position control, the focus being formed on the anode of an X-ray tube with magnetic bearings. The X-ray apparatus comprises a focus position sensing device cooperating with electronic means associated with the magnetic bearings, in order to control the position of the focus by displacing a rotor under the action of the magnetic bearings.

Abstract: An x-ray tube for producing a high-efficiency beam and especially a pencil beam as applicable to the field of radiology and more especially digital radiology comprises an anode provided with a rectilinear bore and a cathode for generating an electron beam which enters the bore. The internal walls of the bore constitute an anode target which is bombarded by the electron beam in order to produce at least one x-ray beam which emerges from one end of the bore.

Abstract: The invention relates to a process for the controlling of the position of the focus of an X-ray tube, a applicable to the monitoring of X-ray equipment equipped with X-ray tubes and to the installation of the latter in shields. The invention also relates to a control apparatus for performing the above process. According to the process of the invention, the image of the focus of an X-ray tube is produced on two X-radiation sensitive, contiguous detector means. Each of the detector means supplied an output signal, whose amplitude is a function of the distribution of said image of said detector means. The output signals are applied to a comparison means, which supplies a difference signal linked with the position of the focus along a first given axis.

Abstract: In an X-ray tube comprising a rotating anode mounted on magnetic bearings, the flow of anode current within the tube takes place without any contact by means of a stationarily fixed hollow anode in which is placed a cathode coupled rotationally to the rotating anode. The hollow anode is associated with heating means and the cathode is heated by thermal radiation within the hollow anode.

Abstract: The invention relates to a rotating anode X-ray tube provided with a charge flow device, in which the anode current of the tube is established between an emitter coupled in rotation to the rotating anode, as well as a fixed collector. The latter is electrically connected to high voltage and the emitter is electrically connected to the rotating anode, having at least one part with a tapered end constituting an electron emissive zone. These electrons are trapped by the collector, so as to establish the anode current of the tube without any material contact between the emitter and the collector. The invention is applicable to radiology in general and more specifically to medical diagnosis.

Abstract: The invention relates to the polarization of a cathode of an X-ray tube by a high voltage cable comprising less conductors than the tube has polarization terminals. The missing voltages are processed by a device according to the invention, which comprises a voltage divider positioned between two of the voltages applied to the input terminals. It permits the use of standard long high voltage cables with limited stray capacitance without inducing dimensional control losses with respect to the tube foci.Application to multifocus X-ray sources.