A computer tomograph (1) for mammographic x-ray imaging includes a MBFEX tube (20) and a flat-bed x-ray detector (30). Cathodes (40) are arranged in a fixed manner in rows in the MBFEX tube (20), the cathodes (40) being provided for the field emission of electrons. Geometry, radiation density and wavelength range of an x-ray beam (b) can be set. The MBFEX tube (20) is movable parallel (z) to the flat-bed x-ray detector (30). The flat bed x-ray detector (30) includes a moveable x-ray screen (31), the opening of which can be set. Using the x-ray screen (31), an imaging area (A) on the detector surface (D) of the flat-bed x-ray detector (30) can be selected and moved. Compared to conventional computer tomographs having rotating x-ray components, the computer tomograph (1) has a lighter and more compact design, with which a particularly small focal spot size is achieved.

A position detection unit is disposed at an exposure position that is included in a camera image and a field of view of a camera and outputs a position signal indicating the position of a part of a peripheral portion of an electronic cassette. The calculation unit calculates an in-image cassette position which is the position of the electronic cassette in the camera image, on the basis of the position, direction, and size of the position detection unit in the camera image and the position signal. A composite image generation unit generates a composite image of the camera image and a cassette frame indicating the in-image cassette position. A display controller displays the composite image on a touch panel.

A system (SC) for controlling operation of a multi-focal-spot X-ray imager (IA). The system comprises a projection direction determiner (PDD) configured to determine a projection direction for an object (OB) to be imaged, based on a geometric structure of a model m(OB) for the object (OB). A selector (SX) of the system is configured to select, from the imager (IA)'s plurality of focal-spot-detector pairs (IPj) with different optical axes (OXj), at least one target pair whose optical axis corresponds to the determined projection direction.

A method for X-ray imaging includes determining one or more pre-shot parameters corresponding to a region of interest in a subject based on an optical image of the region of interest obtained from an optical sensor. The method further includes controlling an X-ray device to generate a pre-shot X-ray image using a first X-ray dosage, based on the one or more-pre-shot parameters. The method also includes determining at least one main-shot parameter based on the pre-shot X-ray image. The method includes controlling the X-ray device to generate a main-shot X-ray image using a second X-ray dosage greater than the first X-ray dosage, based on the at least one main-shot parameter.

A C-arm X-ray apparatus includes an x-ray emitter (5) and an X-ray detector (4) which are maintained on a C-arm (2) mounted on a reference plane. The x-ray emitter (5) has nanorods as electron emitters and has an elongated structure which is at least partially aligned along a surface normal of the reference plane.

An x-ray examination arrangement includes an x-ray radiation source arranged at a source position, at least two x-ray detectors having active detector areas and being arranged such that the active detector areas capture different solid angle ranges with respect to x-ray radiation produced by the x-ray radiation source and emanating from the source position, and a control device configured to calculate a projection onto a virtual detector plane based on radiographs respectively captured by the at least two x-ray detectors and spatial poses of the at least two x-ray detectors relative to the source position, and provide a combined radiograph for the virtual detector plane based on the projection. In addition, a method for operating the x-ray examination arrangement and a computed tomography device are provided.

A method is provided for determining a relative position of an object in relation to an x-ray imaging apparatus for creating an x-ray and a recorded image. The method includes brining an object in a ray path of the x-ray into a first position. The x-ray is created with a first focus point by an x-ray source and a first recorded image of the object in the first position is created by the x-ray focused on a first focus point. In the first recorded image, at least one defined geometry in and/or on the object is imaged. A measure for a change in the focus point towards a second focus point is undertaken at the x-ray source. The x-ray with the second focus point is created by the x-ray source and a second recorded image of the object in the first position is created by the x-ray focused on the second focus point. In the second recorded image, the at least one defined geometry is imaged. A distance from the object to the x-ray source and/or to the x-ray detector is determined based on the change in the focus point, as well as on the basis of the imagings of the at least one defined geometry in the first and the second recorded image.

Novel and advantageous systems and methods for performing X-ray imaging by using an X-ray source with source grating functionality incorporated therein are provided. An electron beam can be electromagnetically manipulated such that the X-ray source emits radiation in a pattern that is the same as if the radiation had already passed through a source grating.

A variable stop apparatus for arrangement between an X-ray source and an object to be measured in a CT-scanner and a CT-scanner including the variable stop apparatus are provided. The variable stop apparatus includes a stop carrier that is pivotable about a pivot axis. The stop carrier has at least two stops. The at least two stops are in each case configured to be brought into a predetermined angular position by pivoting the stop carrier. The at least two stops are arranged at different longitudinal positions with respect to a longitudinal direction that is defined by the pivot axis.

A computer tomograph (1) for X-ray imaging includes a rotationally fixed gantry (2) that is displaceable at most in the axial direction (z). A plurality of X-ray emitters (3) and X-ray detectors (4) is arranged in the gantry (2) in a fixed manner about a central geometrical axis (z), in each case opposite to one another and offset with respect to each other in the direction of the central axis (z). The X-ray emitters (3) have cathodes (5) as electron emitters, which are separately connected to emitter controls (25) and cooperate with a common extraction grid (26) connected upstream of at least one focusing electrode (27). In comparison to conventional computer tomographs having rotating or rigidly arranged technical X-ray components, the computer tomograph (1) has a light and compact design.