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.

Some embodiments include a system, comprising: an enclosure configured to enclose a vacuum; a cathode disposed within the enclosure; an anode disposed within the enclosure configured to receive a beam of electrons from the cathode; a motor disposed within the enclosure and configured to rotate the anode in response to a drive input; and a circuit electrically connected to the drive input, and configured to generate a phase signal based on a voltage of the drive input and a current of the drive input, the phase signal indicating a phase difference between the voltage of the drive input and the current of the drive input.

An improved X-ray source is disclosed. The improved X-ray source has an enclosure, electron guns, a first set of address lines extending through the enclosure, a second set of address lines extending through the enclosure, and nodes defined by the intersection of the first and second set of address lines. Each of the electron guns is coupled to one of the nodes such that a state of each electron gun is uniquely controlled by modulating a state of one of the first set of address lines and one of the second set of address lines.

Disclosed is a portable X-ray generation device, which uses an electric field emission X-ray source, and is thus advantageous in reducing weight and volume and has excellent reliability in X-ray emission performance. The portable X-ray generation device according to the present invention includes an electric field emission X-ray source, which includes a cathode electrode having an electron emitter, an anode electrode having an X-ray target surface, and a gate electrode between the cathode electrode and the anode electrode; and a driving signal generator configured to generate at least three driving signals applied to the cathode electrode, the anode electrode, and the gate electrode, respectively, by direct current power having a predetermined voltage, wherein the driving signal generator includes a current controller maintaining a tube current between the anode electrode and the cathode electrode to have a constant value during X-ray emission.

Disclosed is a portable X-ray generation device, which uses an electric field emission-type X-ray source, and is thus advantageous in reducing weight and volume and has excellent reliability in X-ray emission performance. The portable X-ray generation device according to the present invention comprises: an electric field emission X-ray source, which includes a cathode electrode having an electron emission source, an anode electrode having an X-ray target surface, and a gate electrode between the cathode electrode and the anode electrode; an X-ray emission cone, which has a cone shape having an increasing diameter toward the front thereof, is disposed in front of an X-ray emission point of the electric field emission X-ray source, and controls an emitted X-ray in the form of an X-ray beam having a predetermined angle range; and a driving signal generation unit for generating at least three driving signals applied to the cathode electrode, the anode electrode, and the gate electrode, respectively, by a direct current power source having a predetermined voltage, wherein the entire weight of the device is 0.8 kg to 3 kg, and the X-ray emission output thereof can be implemented to be 120 W to 300 W.

An embodiment of the inventive concept provides an X-ray tube including a chamber having a hollow pillar shape using a first axis as a central axis, a cathode electrode disposed on a bottom surface of the chamber, an emitter provided at a position at which the cathode electrode meets the first axis, an anode electrode including a through-hole using the first axis as a central axis and a target layer inclined to the first axis, a gate electrode disposed between the cathode electrode and the anode electrode and having an opening exposing the emitter, a focusing electrode disposed between the gate electrode and the anode electrode, a window spaced apart from the target layer of the anode electrode, and a window electrode provided on a top surface of the chamber to fix a side surface of the window. Here, the window electrode is grounded.

A device and method for creating beam formed X-Ray radiation using radio frequency (RF) modulated field emission X-ray sources is described. A radio frequency RF source generates a RF control signal which is supplied to an array of phase delay elements to generate multiple individually controlled phase delayed RF signals. These are then directly provided to each of a plurality of field emission sources (via a matching circuit) to generate a plurality of RF modulated electron current, or beam, each at the same frequency and phase delay of the phase delayed RF signals. Each of the electron beams impacts a target anode to generate X-rays also at the same frequency and phase delay of the phase delayed RF signals. By controlling each of the phase delay elements a beamformed X-ray radiation pattern can be generated.

Systems and methods for medical imaging. The method may include acquiring a tube voltage switching waveform for a radiation source of a medical device. The method may include determining a tube current switching period based on the tube voltage switching waveform. The method may include determining a sampling period correlated with the tube current switching period. The method may include acquiring projection data according to the sampling period. The method may further include reconstructing an image based on the acquired projection data.

The present invention relates to an apparatus for generating X-rays. It is described to produce (210) with a power supply (30) a voltage. A cathode (22) of an X-ray source (20) is positioned (220) relative to an anode (24) of the X-ray source. Electrons are emitted (230) from the cathode. Electrons emitted from the cathode interact (240) with the anode with energies corresponding to the voltage. X-rays are generated (250) from the anode, wherein the electrons interact with the anode to generate the X-rays. The X-ray source is controlled (260), such that a plurality of first X-ray pulses is generated each having a first X-ray flux, wherein the first X-ray pulses are temporally separated from each other. The X-ray source is controlled (270), such that a least one second X-ray pulse is generated having a second X-ray flux that is substantially less than the first X-ray flux, wherein the at least one second X-ray pulse is generated temporally between consecutive pulses of the first X-ray pulses.

A system for grid control of an electromagnetic ray tube is provided. The system includes a power source, a rectifier, and a grid conductor. The power source is disposed apart from the electromagnetic ray tube and operative to generate an AC current. The rectifier is integrated into the electromagnetic ray tube and electrically coupled to a grid electrode of the electromagnetic ray tube. The grid conductor electrically couples the power source to the rectifier. The rectifier is operative to convert the AC current to a DC current that powers the grid electrode.