A gantry includes two X-ray source rings and a detector ring. Each X-ray source ring includes a plurality of X-ray sources arrayed circumferentially. The detector ring is provided next to the X-ray source ring and includes a plurality of X-ray detectors arrayed circumferentially. Each of the plurality of X-ray detectors detects X-rays from the X-ray source ring. A data collection circuit collects raw data corresponding to the intensity of the detected X-rays. A reconstruction unit reconstructs the collected raw data into a CT image based on digital data.

A x-ray apparatus of the present application comprises: a vacuum box which is sealed at its periphery, and the interior thereof is high vacuum; a plurality of electron transmitting units arranged in a linear array and installed on the wall at one end within the vacuum box, each electron transmitting unit is independent to each other; the electron transmitting unit having: a heating filament; a cathode connected to the heating filament; a grid arranged above the cathode opposing the cathode; anode made of metal and installed at the other end of the vacuum box, and in the direction of length, the anode is parallel to the plane of the grid of the electron transmitting unit, and in the direction of width, the anode has a predetermined angle with respect to the plane of the grid of the electron transmitting unit.

Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode.

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.

A method is for spatially influencing a focal spot of an X-ray source that generates X-ray radiation, to an associated X-ray source, to an associated system and to an associated computer program product. The method according to at least one embodiment includes: producing a focal spot on an anode by way of an electron emitter including a plurality of emitter segments, individually controllable to emit electrons; determining at least one actual value of a spatial extent and/or of a position of the produced focal spot; comparing the at least one actual value with a specified reference value of the focal spot; and controlling the emitter segments based upon the comparison of the at least one actual value and the reference value such that the at least one actual value converges toward the reference value, thereby spatially influencing the focal spot of the X-ray source that generates X-ray radiation.

Provided is a field emission apparatus including a pipe-shaped emitter holder comprising an electrically conductive material and a first internal space communicated in a first direction, and an emitter electrode having one or more yarns each having a structure extending in the first direction in which a plurality of CNTs that extend in the first direction are aggregated, and the emitter electrode is inserted in the first internal space while extending in the first direction.

It is a CNT device (1) (carbon-metal structure) equipped with a carbon nanotube layer (2) (CNT layer 2; same hereafter) on a metal pedestal (4). The metal pedestal (4) is brazed to the CNT layer (2) with a brazing material layer (3) interposed therebetween. When manufacturing the CNT device (1), firstly, the CNT layer (2) is formed on a heat-resistant textured substrate (6). Next, the metal pedestal (4) is brazed to the CNT layer (2) that is on the heat-resistant textured substrate (6) with the brazing material layer (3) interposed therebetween. Then, the metal pedestal (4) (and the CNT layer 2) is peeled off the heat-resistant textured substrate (6) to transfer the CNT layer (2) from the heat-resistant textured substrate (6) to the metal pedestal (4).

The X-ray imager combines a pulsed X-ray source with a time-sensitive X-ray detector to provide a measure of ballistic photons with a reduction of scattered photons. The imager can provide a comparable contrast-to-noise X-ray image using significantly less radiation exposure than conventional X-ray imagers, notably about half of the radiation.

Provided is a method for manufacturing an electric field emission device. The method for manufacturing the electric field emission device includes winding a carbon nanotube yarn around outer circumferential surfaces of a metal plate in a first direction, pressing both side surfaces of the metal plate through a pair of metal structures, wherein a top surface of the metal plate is exposed from the metal structures, and an area of the top surface of the metal plate is less than that of each of both the side surfaces of the metal plate, and cutting the carbon nanotube yarn at an edge portion of the top surface of the metal plate in the first direction to form a plurality of emitters.

An X-ray tube of an embodiment includes an anode; and an electron emission device. In an embodiment, the electron emission device includes at least one electron emitter including at least one emission surface and at least one barrier grid, the at least one barrier grid being spaced apart from the at least one emission surface of the electron emitter and includes a definable number of individually controllable grid segments. According to an embodiment, at least one individually definable grid voltage is applicable to each of the grid segments. In a simple manner, an electron-emission device of an embodiment permits the image quality to be adjusted with minimal anode loading.