Compagnie Generale De Radiologie

Thomson-csf

Jacques Delair

Jacques Le Guen

Andre Plessis

Jacques Leguen

Andre Laffitte

Dang T Quang

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.

X-Ray tube cathode multiple polarization device and a radiation source

The invention relates to a transverse axial tomographic system using a computer. This system includes a single casing in the form of a toroid on which are carried a number of X-ray tubes that can be simultaneously or successively started very rapidly for thus irradiating a body positioned about the axis of the casing and a plurality of detectors receiving the X-rays attenuated by the body. Such a system permits tomographic slices of organs such as the heart while they are moving.

Tomographic system having a single case on which are carried the X-ray

An x-ray tube providing a flat, fan-shaped uniform x-ray beam. The tube includes inside a vacuum glass envelope, a cathode or cathodes, a fixed or cylindrical rotating anode, and an anti-divergence diaphragm. The anti-divergence diaphragm has an opening, through which passes the beam. The walls of the opening have the shape of a sector of the fan-shaped beam in one plane (z-z'), and are flat in a perpendicular plane. A plurality of x-ray absorbing blades are positioned in the opening parallel to the fan-shaped side dividing the opening and the beam passing therethrough, thereby minimizing overall divergence of the beam. A plurality of cathodes may be used in the rotating anode tube, each separately focusable to provide beams of different intensity, and alternately operable.

Small divergence x-ray tube

A method and circuit arrangement for improving the definition of the focal spots of X-ray tubes which comprises periodically varying the bias voltage applied to the concentrating electrode of the tube, focalizing the eletron beam emitted by the filament, between a negative minimum or zero value and a negative maximum value, with a voltage waveform whose frequency is higher than 10 kilohertz, wherein this bias voltage has to assume at least the two extreme values frequently, while a direct-current high voltage is being applied between the cathode (filament) and the anode (target) during the exposure time.

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Paris, France

Jacques Delair