An inspection radiation source is provided. The inspection radiation source includes an electron accelerator for generating an electron current, and a target for the electron current including a first part and a second part. This first part is configured to be at least partly exposed to the electron current on an impact area having a first width in a direction substantially perpendicular to the electron current, and inhibit propagation of the electron current. The second part has a second width in the direction substantially perpendicular to the electron current, the second width of the second part being smaller than the first width of the impact area, the second part being configured to be at least partly exposed to the electron current, and generate inspection radiation by emitting X-rays in response to being exposed to the electron current.

A voltage-multiplier can be more compact by arrangement in a stack of separate voltage-multiplier-stages. Each of the voltage-multiplier-stages can include electronic-components on a planar-face of a circuit-board. The planar-face of each circuit-board can be parallel with respect to other circuit-boards in the stack. The electronic-components on each voltage-multiplier-stage can be configured to multiply an input-voltage to provide an output-voltage with a higher voltage than the input-voltage. Each voltage-multiplier-stage in the stack can be electrically coupled to two adjacent voltage-multiplier-stages, except that two outermost voltage-multiplier-stages of the stack can be electrically coupled to only one adjacent voltage-multiplier-stage of the stack.

A voltage-multiplier can be more compact by arrangement in a stack of separate voltage-multiplier-stages. Each of the voltage-multiplier-stages can include electronic-components on a planar-face of a circuit-board. The planar-face of each circuit-board can be parallel with respect to other circuit-boards in the stack. The electronic-components on each voltage-multiplier-stage can be configured to multiply an input-voltage to provide an output-voltage with a higher voltage than the input-voltage. Each voltage-multiplier-stage in the stack can be electrically coupled to two adjacent voltage-multiplier-stages, except that two outermost voltage-multiplier-stages of the stack can be electrically coupled to only one adjacent voltage-multiplier-stage of the stack.

A method for imaging a sample by means of an X-ray detector is disclosed, including providing an electron beam interacting with a target to generate X-ray radiation emitted from an X-ray spot on the target, moving the sample relative to the target, deflecting the electron beam such that the X-ray spot is moved over the target simultaneously and in accordance with the movement of the sample, and detecting X-ray radiation emitted from the X-ray spot and interacting with the sample.

A method for imaging a sample by means of an X-ray detector is disclosed, including providing an electron beam interacting with a target to generate X-ray radiation emitted from an X-ray spot on the target, moving the sample relative to the target, deflecting the electron beam such that the X-ray spot is moved over the target simultaneously and in accordance with the movement of the sample, and detecting X-ray radiation emitted from the X-ray spot and interacting with the sample.

An X-ray radiator and an X-ray assembly are disclosed. The X-ray radiator according to an embodiment has an evacuated X-ray tube housing, mounted to be rotatable about a rotation axis, the X-ray tube housing including an anode and an electron source. The anode is arranged within the X-ray tube housing non-rotatably relative to the X-ray tube housing and is configured to generate X-ray radiation via electrons impacting upon a focal spot of the anode, the electron source being mounted substantially stationary within the X-ray tube housing relative to the rotation axis. The electron source has a main emitter and at least one subsidiary emitter for emitting electrons. The electron emission of the main emitter and/or of the at least one subsidiary emitter is controllable such that a spatial movement of the focal spot due to a movement of the electron source is reduced.

An X-ray radiator and an X-ray assembly are disclosed. The X-ray radiator according to an embodiment has an evacuated X-ray tube housing, mounted to be rotatable about a rotation axis, the X-ray tube housing including an anode and an electron source. The anode is arranged within the X-ray tube housing non-rotatably relative to the X-ray tube housing and is configured to generate X-ray radiation via electrons impacting upon a focal spot of the anode, the electron source being mounted substantially stationary within the X-ray tube housing relative to the rotation axis. The electron source has a main emitter and at least one subsidiary emitter for emitting electrons. The electron emission of the main emitter and/or of the at least one subsidiary emitter is controllable such that a spatial movement of the focal spot due to a movement of the electron source is reduced.

The X-ray tube disclosed herein includes an electron emission part including an electron emission element using a cold cathode; an anode part having an anode surface with which an electron emitted from the electron emission part collides; and a focusing structure disposed between the electron emission part and a target part disposed on the anode surface. The focusing structure has a plurality of focal point areas that are applied with a voltage in a mutually independent manner. The electron emission part has first and second electron beam emission areas that are on/off controlled in a mutually independent manner. The X-ray tube is designed in such a way that a collision area of the electron beam emitted from each of the first and second electron beam emission areas on the anode surface moves in response to a voltage applied to the focusing structure.

The X-ray tube disclosed herein includes an electron emission part including an electron emission element using a cold cathode; an anode part having an anode surface with which an electron emitted from the electron emission part collides; and a focusing structure disposed between the electron emission part and a target part disposed on the anode surface. The focusing structure has a plurality of focal point areas that are applied with a voltage in a mutually independent manner. The electron emission part has first and second electron beam emission areas that are on/off controlled in a mutually independent manner. The X-ray tube is designed in such a way that a collision area of the electron beam emitted from each of the first and second electron beam emission areas on the anode surface moves in response to a voltage applied to the focusing structure.

An imaging system (202) includes an X-ray radiation source (210) configured to emit radiation that traverses an examination region. The imaging system further includes a controller (220). The controller is configured to control an X-ray tube peak voltage of the X-ray radiation source to switch between at least two different X-ray tube peak voltages during a kVp switched spectral scan. The controller is further configured to control a grid voltage of the X-ray radiation source to follow the X-ray tube peak voltage during the spectral scan. The controller adjusts the grid voltage based on a predetermined mapping between a currently applied X-ray tube peak voltage and a corresponding grid voltage for a given focal spot size, thereby maintaining the given focal spot size throughout the spectral scan.