Disclosed is an X-ray tube for improving electron focusing, which allows thermoelectrons emitted from a filament to efficiently reach a target of an X-ray irradiation window. To achieve this, the X-ray tube includes: a thermionic emitter configured to emit thermoelectrons by application of a negative high voltage; a focusing tube configured to focus the thermoelectrons emitted from the thermionic emitter; an X-ray irradiation window configured to irradiate X-rays outside by the thermoelectrons bombarded on a target distributed on the X-ray irradiation window, to generate the X-rays after the thermoelectrons pass through the focusing tube; a tube part including both the thermionic emitter and the focusing tube; and a housing surrounding the tube part, wherein the focusing tube and the housing are configured to have a same potential such that movement directions of the thermoelectrons are directed to the X-ray irradiation window.

According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

The present invention relates to an X-ray tube for X-ray analysis. The X-ray tube comprises an anode having a target surface and a cathode. The cathode comprises an emission loop. The emission loop extends around an axis that passes through the anode, and the cathode and the anode are spaced apart from one another along the axis. Electrons emitted from the cathode irradiate the target surface of the anode to produce X-rays. The X-ray tube further comprises an electron beam guide. The electron beam guide is configured to guide electrons emitted by the cathode, so as to irradiate an area of the anode. The irradiated area is enclosed by a single boundary.

A source for generating ionizing radiation and in particular x-rays, to an assembly includes a plurality of sources and to a process for producing the source. The source for generating ionizing radiation comprises: a vacuum chamber; a cathode that is able to emit an electron beam into the vacuum chamber; an anode that receives the electron beam and that comprises a target that is able to generate ionizing radiation from the energy received from the electron beam; and an electrode that is placed in the vicinity of the cathode and forming a wehnelt. The electrode is formed from a conductive surface adhering to a concave face of a dielectric.

According to one embodiment, an X-ray tube includes an anode including a target surface, and a cathode including a first filament and a focusing electrode. The focusing electrode includes a valley bottom portion, a first inclined plane sloping up from the valley bottom portion in a direction of the anode, a first focusing groove, and a first storage groove. 1 is greater than 0. The first focusing groove has a longitudinal axis. One end portion on the first extension line side of the first focusing groove is closer to a first reference surface than the other end portion of the first focusing groove.

The present disclosure relates to a method and system for adjusting a focal point position of an X-ray tube. The method may include: obtaining a first thermal capacity and a first position of a focal point of an X-ray tube; obtaining a second thermal capacity of the X-ray tube; determining a second position of the focal point the X-ray tube based on the second thermal capacity; determining a target grid voltage difference of a focusing cup of the X-ray tube based on the first position and the second position of the focal point; and adjusting the X-ray tube based on the target grid voltage difference.

According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

An emitter (3) and a target (7) are arranged so as to face each other in a vacuum chamber (1), and a guard electrode (5) is provided at an outer circumferential side of an electron generating portion (31) of the emitter (3). The emitter (3) is supported movably in both end directions of the vacuum chamber (1) by the emitter supporting unit (4) having a movable body (40). The emitter supporting unit (4) is operated by an operating unit (6) connected to the emitter supporting unit (4). By operating the emitter supporting unit (4) by the operating unit (6), a distance between the electron generating portion (31) of the emitter (3) and the target (7) is changed, and a position of the emitter (3) is fixed at an arbitrary distance, then field emission is performed with the position of the emitter (3) fixed.

A cylindrical X-ray tube having an outer insulating layer, a cathode electrode and an anode electrode disposed at both ends of the outer insulating layer, a gate electrode disposed between the cathode and anode electrodes, an emitter, and a target, comprises an inner insulating layer which is disposed between the cathode electrode and the outer insulating layer, is formed to extend downward in a coaxial direction with the outer insulating layer, and is pre-adjusted in order to secure an insulating distance between the cathode electrode and the gate electrode. Thus, by providing a separate internal insulating layer extending coaxially with the external insulating layer between the cathode electrode and the external insulating layer, the insulating distance between the cathode electrode and the gate electrode, the insulating distance between the cathode electrode and the anode electrode may be easily adjusted, so that a desired insulating capability can be secured.

The present invention provides an X-Ray emitting device that comprises a focusing electrode composed of a ceramic-based material, which can be manufactured by a simple process and is excellent in durability.