X-RAY TUBE

摘要

The present invention relates to an X-ray tube structure for obtaining a high anode current output within a predetermined range of working voltages. The anode current output can be increased by neutralising the negative volumetric charge of the electrons emitted by the cathode using the positive ions from a gas which is inert relative to the cathode material. The positive ions are generated in the cathode-anode gap of the X-ray tube by the ionising interaction between the flow of electrons and the gas molecules moving from the cathode to the anode. The X-ray tube of the present invention includes a cathode and an anode arranged in a working volume filled with a gas which is inert relative to the cathode material at a pressure of up to (0.001 DIVIDED 0.5)P. The pressure P is selected in the left branch of a Paschen's curve according to the maximal voltage value at the anode and to the cathode-anode distance of the X-ray tube. This structure provides for a high anode current output, can be easily manufactured and also increases the service duration of the cathode and the anode due to the convection cooling mechanism in the rarefied gas, which is particularly important during pulse-mode operation.