Abstract: An X-ray apparatus includes an X-ray source and a detector operating in conjunction with the X-ray source. The X-ray apparatus also includes a correction object having a defined geometry and/or known radiation absorption behavior disposed between the X-ray source and the detector. The correction object is detectable by the detector and configured to indicate characteristics of the X-ray source such as a focal spot position.

Abstract: An x-ray apparatus includes an x-ray emitter having an x-ray tube, a rotary anode disposed in the x-ray tube, and a drive for the rotary anode. The drive includes a reluctance motor having a stator disposed outside the x-ray tube and a rotor disposed inside the x-ray tube. The rotor is mechanically connected to the rotary anode.

Abstract: A computed tomography system has a gantry with a rotor side that can be rotated around a system axis during operation, at which at least one x-ray tube is mounted. To cool the at least one x-ray tube a liquid cooling system is equipped with a fluid volume filled with cooling liquid, the fluid volume extends over distances of different sizes from the system axis. The fluid volume is located on the rotor of the gantry and thus is exposed to centrifugal force during operation. To increase pressure in the cooling system, a flexible compensation volume and a movable mass element that rotate with the gantry are provided. The mass element is arranged such that the centrifugal force acting on the mass element during operation causes pressure to be exerted on the cooling liquid.

Abstract: A rotary anode for an X-ray tube includes a ceramic base body that carries a focal path for emitting X-rays during electron irradiation. The ceramic base body is made of a mixture of silicon carbide and at least one high temperature-resistant diboride.

Abstract: In a method for applying an electron absorber layer to a substrate, an electron absorber layer is produced from a composite material, by coating the substrate with a metallic material, and material inclusions made from an additional material are embedded in the metallic material during coating. The metallic material contains aluminum, magnesium, cobalt, iron, chromium, titanium, nickel, copper, or an alloy or mixture thereof. The additional material contains one or more of the following substances: boron, carbon or silicon, a mixture of these elements, one or more chemical compounds made from or having at least two of these elements, or a mixture of such chemical compounds.

Abstract: An x-ray tube has an anode and a thermionic emitter with multiple emitter regions spaced from one another that generate, between the emitter and the anode, an electron beam composed of multiple partial beams generated by the respective emitter regions. Between the emitter and the anode is at least one control electrode arrangement that generates a variable electrical field and that has a number of passages to control the respective partial beams. Thus control electrode arrangement has a number of control electrode layers. The individual emitter regions and the control electrodes are arranged and controlled relative to one another to cause substantially the entirety of each partial beam generated by the respective emitter regions to proceed through a passage respectively associated with that partial beam.

Abstract: A cathode HAS a cathode head in which a surface emitter is arranged that emits electrons upon application of a heating voltage. The surface emitter is fashioned as a parallel surface emitter with at least two emitter surfaces spaced apart from one another, to which at least one electrically conductive cutoff electrode is fed that is galvanically separated from the parallel surface emitter. Such a cathode has a good cutoff capability.

Abstract: A thermionic emission device, in particular for use in an x-ray tube, has an indirectly heated primary emitter that is fashioned as a flat emitter with an unstructured primary emission surface, and a heating emitter that is fashioned as a flat emitter with a structured heat emission surface. The primary emitter and the heating emitter each has at least two terminal lugs, and the primary emission surface and the heat emission surface are aligned essentially parallel to one another. The emission device provides an optimally high quality of the focal spot with a simple design and, given high thermal load, an unwanted widening or defocusing of the electron beam is avoided by the terminal lugs of the primary emitter being aligned essentially perpendicular to the primary emission surface and not protruding beyond the primary emission surface in the lateral direction.

Abstract: An x-ray tube has a backscatter electron trap to prevent extra focal radiation caused by backscattered electrons from the focal spot from passing through the beam exit window to an exterior of the x-ray tube. The backscatter electron trap has a surface that faces the x-ray beam in the x-ray tube. No portion of that surface is visible both from an arbitrary point in the x-ray beam outside of the x-ray tube and from an arbitrary point at the focal spot.

Abstract: An x-ray tube has a cathode and a anode, and a catching device that captures backscattered electrons from the anode in the operating state of the x-ray tube. The catching device minimizes unwanted energy generation by the backscattered electrons in the catching device and the anode while maintaining a high quality of the focus by the catching device being electrically insulated with respect to the anode and the cathode and being placed at an electrical potential having a value between the value of the electrical potential of the anode and the value of the electrical potential of the cathode, and the amount of the difference between the potential of the catching device and the potential of the anode is in the range from 1% to 40% of the amount of the difference between the potential of the cathode and the potential of the anode.

Abstract: In a thermionic surface emitter and an associated method to operate an x-ray tube, the surface emitter has a conductor path in its emission surface, the conductor path having at least one current entrance point and at least one current exit point. In the thermionic surface emitter, the width of the conductor path is variable i.e. is non-constant or non-uniform. The electrical resistance of the emitter structure thus varies along the heating current path, with the consequence that a symmetrical emission structure can be achieved at a working point established by the hardware geometry.

Abstract: An x-ray tube has a number of emitters that generate respective electron beams, and has a common anode at which the electron beams strike on a surface to generate x-rays. A high x-ray dose power with a long lifespan are achieved while being able to quickly vary the x-ray dose power by using a superimposed intensity distribution from the x-ray beams, which is measured by a detector, to optimize the x-ray beams on the surface.

Abstract: A computed tomography system has a gantry with a rotor side that can be rotated around a system axis during operation, at which at least one x-ray tube is mounted. To cool the at least one x-ray tube a liquid cooling system is equipped with a fluid volume filled with cooling liquid, the fluid volume extends over distances of different sizes from the system axis. The fluid volume is located on the rotor of the gantry and thus is exposed to centrifugal force during operation. To increase pressure in the cooling system, a flexible compensation volume and a movable mass element that rotate with the gantry are provided. The mass element is arranged such that the centrifugal force acting on the mass element during operation causes pressure to be exerted on the cooling liquid.

Abstract: An x-ray radiator has an x-ray tube with a vacuum housing arranged in a radiator housing in which a coolant circulates. The vacuum housing has a porous coating, at least at parts thereof, on surfaces facing the coolant. The heat transfer between the vacuum housing and the coolant is thereby improved, such that the x-ray radiator can be more highly thermally loaded.

Abstract: In a method for applying an electron absorber layer to a substrate, an electron absorber layer is produced from a composite material, by coating the substrate with a metallic material, and material inclusions made from an additional material are embedded in the metallic material during coating. The metallic material contains aluminum, magnesium, cobalt, iron, chromium, titanium, nickel, copper, or an alloy or mixture thereof. The additional material contains one or more of the following substances: boron, carbon or silicon, a mixture of these elements, one or more chemical compounds made from or having at least two of these elements, or a mixture of such chemical compounds.

Abstract: A cathode has an emission layer that thermionically emits electrons upon exposure with a laser beam. The material of the emission layer has a product of density (?), measured in kg m 3 , heat capacity (Cp), measured in J kg ? ? K and heat conductivity (?), measured in W mK that is, at room temperature, maximally 500,000 J 2 m 4 ? K 2 ? s . Such a cathode has an improved thermionic emission of electrons.

Abstract: In a focus detector arrangement and method for an x-ray apparatus for generating projection or tomographic phase-contrast images of an examination subject, a beam of coherent x-rays is generated by an anode that has areas of different radiation emission characteristics arranged in bands thereon, that proceed parallel to grid lines of a phase grid that is used to generate the phase-contrast images.

Abstract: An x-ray tube has a cathode and a anode, and a catching device that captures backscattered electrons from the anode in the operating state of the x-ray tube. The catching device minimizes unwanted energy generation by the backscattered electrons in the catching device and the anode while maintaining a high quality of the focus by the catching device being electrically insulated with respect to the anode and the cathode and being placed at an electrical potential having a value between the value of the electrical potential of the anode and the value of the electrical potential of the cathode, and the amount of the difference between the potential of the catching device and the potential of the anode is in the range from 1% to 40% of the amount of the difference between the potential of the cathode and the potential of the anode.

Abstract: An x-ray tube has an anode and a thermionic emitter with multiple emitter regions spaced from one another that generate, between the emitter and the anode, an electron beam composed of multiple partial beams generated by the respective emitter regions. Between the emitter and the anode is at least one control electrode arrangement that generates a variable electrical field and that has a number of passages to control the respective partial beams. Thus control electrode arrangement has a number of control electrode layers. The individual emitter regions and the control electrodes are arranged and controlled relative to one another to cause substantially the entirety of each partial beam generated by the respective emitter regions to proceed through a passage respectively associated with that partial beam.

Abstract: A thermionic emission device, in particular for use in an x-ray tube, has an indirectly heated primary emitter that is fashioned as a flat emitter with an unstructured primary emission surface, and a heating emitter that is fashioned as a flat emitter with a structured heat emission surface. The primary emitter and the heating emitter each has at least two terminal lugs, and the primary emission surface and the heat emission surface are aligned essentially parallel to one another. The emission device provides an optimally high quality of the focal spot with a simple design and, given high thermal load, an unwanted widening or defocusing of the electron beam is avoided by the terminal lugs of the primary emitter being aligned essentially perpendicular to the primary emission surface and not protruding beyond the primary emission surface in the lateral direction.