An X-ray generation apparatus includes an electron gun having a cathode emitting an electron beam, a first housing accommodating the electron gun, a target on which the electron beam emitted from the electron gun is incident, a second housing accommodating the target, and an electron passage extending between the first housing and the second housing and configured to transfer the electron beam from a first internal space of the first housing to a second internal space of the second housing. The electron passage includes a diameter-reduced end portion decreasing in diameter toward the target. The first housing is provided with a first exhaust flow path for evacuating the first internal space in the first housing. The second housing is provided with a second exhaust flow path for evacuating the second internal space in the second housing.

Disclosed herein is an x-ray backscatter apparatus (“apparatus”) for non-destructive inspection of an object. The apparatus includes an x-ray emitter that includes a vacuum tube, an x-ray shield enclosed within the vacuum tube. The x-ray shield includes at least one emission aperture. The apparatus also includes a cathode enclosed within the vacuum tube and that is operable to generate an electron stream. Also included is an anode, enclosed within the vacuum tube and located relative to the cathode, to receive the electron stream and convert the electron stream from the cathode to an x-ray stream, and located relative to the emission aperture to direct at least a portion of the x-ray stream through the at least one emission aperture. Also disclosed are a system and a method that utilize the apparatus.

A computer tomography x-ray tube for generating pulsed x-rays is presented. The x-ray tube comprises an anode and an electron emission unit for generating a pulsed electron beam onto the anode. Furthermore, a rotation mechanism for rotating the anode characterized in that the rotation mechanism is configured for rotating the anode with an angular velocity that varies in time is comprised. The rotation mechanism may also be configured for rotating the anode such that the variation of the angular velocity in time is a continuous oscillation around a mean angular velocity ω.sub.0 in time. In a preferred embodiment the angular velocity ω (t) varies in time according to the following formula:

ω(t)=ω.sub.0+Δω sin Ωt,

wherein ω.sub.0 is a mean angular velocity. In a particular embodiment, the grid switch for generating the pulsed electron beam is comprised and the x-ray tube may be embodied as a stereo tube, in which two focal spots of electron beams are generated in an alternating manner.

An x-ray tube source is disclosed that allows differential phase shift, attenuation, and x-ray scattering features of an object to be acquired in a single exposure. Such multiplexed x-ray tube source includes multiple x-ray spot origins controlled in such a way that each slightly separated spot is temporally modulated “ON and OFF” at differing frequencies. In an x-ray interferometer system, such x-ray tube source forms multiple illumination beams of a single angular view of an object's feature but each with different interference fringe locations. A composite image can be acquired with a high frame-rate digital detector as a component element in such x-ray interferometer system. Such composite image can be subsequently de-multipexed and separately presented according to each spot-source illumination beam. Such isolated images of an object's feature, each having different fringe locations, allows for post-acquisition “fringe-mapping” analysis of the feature's full interaction with x-rays, including refraction, scattering, and absorption.

An x-ray tube source is disclosed that allows differential phase shift, attenuation, and x-ray scattering features of an object to be acquired in a single exposure. Such multiplexed x-ray tube source includes multiple x-ray spot origins controlled in such a way that each slightly separated spot is temporally modulated “ON and OFF” at differing frequencies. In an x-ray interferometer system, such x-ray tube source forms multiple illumination beams of a single angular view of an object's feature but each with different interference fringe locations. A composite image can be acquired with a high frame-rate digital detector as a component element in such x-ray interferometer system. Such composite image can be subsequently de-multipexed and separately presented according to each spot-source illumination beam. Such isolated images of an object's feature, each having different fringe locations, allows for post-acquisition “fringe-mapping” analysis of the feature's full interaction with x-rays, including refraction, scattering, and absorption.

Systems and methods for determining an offset of a position of a focal point of an X-ray tube is provided. The methods may include obtaining at least one parameter associated with an X-ray tube during a scan of a subject and obtaining a position of a focal point of the X-ray tube. The methods may further include determining a target offset of the position of the focal point based on the at least one parameter and a target relationship between a plurality of reference parameters associated with the X-ray tube and a plurality of reference offsets of reference positions of the focal point. The methods may further include causing, based on the target offset, a correction on the position of the focal point of the X-ray tube.

A brushless drive system includes a reluctance rotor and a stator for generating a magnetic flux. The stator has a cylindrical stator yoke, an annular permanent magnet and a coil unit. The reluctance rotor has a cylindrical rotor yoke that is made of a soft-magnetic material, is free from magnetic sources and is configured to be driven about an axis of rotation via the magnetic flux. The permanent magnet and the coil unit are axially spaced apart along the axis of rotation. The stator yoke, the permanent magnet, the rotor yoke and the coil unit form a magnetic circuit for guidance of the magnetic flux. The magnetic circuit is configured such that, between the permanent magnet and the coil unit, an axial direction of the magnetic circuit in the stator yoke and an axial direction of the magnetic circuit in the rotor yoke have opposite signs.

A brushless drive system includes a reluctance rotor and a stator for generating a magnetic flux. The stator has a cylindrical stator yoke, an annular permanent magnet and a coil unit. The reluctance rotor has a cylindrical rotor yoke that is made of a soft-magnetic material, is free from magnetic sources and is configured to be driven about an axis of rotation via the magnetic flux. The permanent magnet and the coil unit are axially spaced apart along the axis of rotation. The stator yoke, the permanent magnet, the rotor yoke and the coil unit form a magnetic circuit for guidance of the magnetic flux. The magnetic circuit is configured such that, between the permanent magnet and the coil unit, an axial direction of the magnetic circuit in the stator yoke and an axial direction of the magnetic circuit in the rotor yoke have opposite signs.

Various methods and systems are provided for x-ray tube conditioning for a computed tomography imaging method. In one embodiment, x-ray may be generated in an x-ray tube of a radiation source prior to a diagnostic scan to warmup the x-ray tube to a desired temperature for the diagnostic scan. The power delivered to the x-ray tube during warmup may be adjusted in a closed loop system based on an initial temperature of the x-ray tube and the desired temperature for the diagnostic scan. During tube warmup, by placing a blocking plate coupled to a collimator blade in a path of the x-ray beam, the x-ray beam may be blocked from exiting a collimator.

Various methods and systems are provided for x-ray tube conditioning for a computed tomography imaging method. In one embodiment, a scout scan may be carried out prior to a diagnostic to warmup the x-ray tube to a desired temperature for the diagnostic scan. A scout scan parameter optimizing algorithm may be used to determine scout scan parameters based on a selected patient absorbed dose range and an amount of energy to be imparted to an x-ray tube during the scout scan preceding a diagnostic scan. By using a hardening filter in the path of the x-ray beam, radiation absorbed dose of the subject being scanned may be limited to the selected patient absorbed dose range.