Abstract: According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

Abstract: According to one embodiment, an X-ray CT apparatus includes processing circuitry. The processing circuitry acquires a plurality of discrete images at a corresponding plurality of discrete positions in a body axis direction of an object, and calculates imaging conditions corresponding to a scan range of a main scan based on the plurality of discrete images.

Abstract: According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

Abstract: According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

Abstract: According to one embodiment, an X-ray computed tomography imaging apparatus includes an X-ray tube, an X-ray detector, and control circuitry. The X-ray tube includes a cathode configured to generate thermoelectrons, an anode configured to generate X-rays upon receiving the thermoelectrons from the cathode, and a regulator configured to apply an electric field or a magnetic field to focus or bias the thermoelectrons from the cathode. The X-ray detector detects the X-rays generated by the anode. The control circuitry controls the regulator to switch at least one of the size and position of the focus of the thermoelectrons from the cathode on the anode between scan and warm-up.

Abstract: According to one embodiment, an X-ray CT apparatus includes processing circuitry. The processing circuitry acquires a plurality of discrete images at a corresponding plurality of discrete positions in a body axis direction of an object, and calculates imaging conditions corresponding to a scan range of a main scan based on the plurality of discrete images.

Abstract: According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

Abstract: According to one embodiment, Switching units are configured to switch the intensity of X-rays to be generated by an anode. An X-ray controller controls the switching units to switch the intensity of the X-rays to be generated by the anode, and controls a rotor control power generator to rotate the anode. When a value approximately equal to an integer multiple of an X-ray intensity switching period designated by a user coincides with the rotor rotation period, the X-ray controller controls the rotor control power generator to shift the thermoelectron collision ranges of the anode in the first turn from thermoelectron collision ranges in the second turn.

Abstract: According to one embodiment, an X-ray computed tomography imaging apparatus includes an X-ray tube, an X-ray detector, and control circuitry. The X-ray tube includes a cathode configured to generate thermoelectrons, an anode configured to generate X-rays upon receiving the thermoelectrons from the cathode, and a regulator configured to apply an electric field or a magnetic field to focus or bias the thermoelectrons from the cathode. The X-ray detector detects the X-rays generated by the anode. The control circuitry controls the regulator to switch at least one of the size and position of the focus of the thermoelectrons from the cathode on the anode between scan and warm-up.

Abstract: According to one embodiment, Switching units are configured to switch the intensity of X-rays to be generated by an anode. An X-ray controller controls the switching units to switch the intensity of the X-rays to be generated by the anode, and controls a rotor control power generator to rotate the anode. When a value approximately equal to an integer multiple of an X-ray intensity switching period designated by a user coincides with the rotor rotation period, the X-ray controller controls the rotor control power generator to shift the thermoelectron collision ranges of the anode in the first turn from thermoelectron collision ranges in the second turn.

Abstract: An X-ray computed tomography apparatus according to an embodiment includes an X-ray tube, a bias power supply, and an X-ray control unit. The X-ray tube includes a cathode, an anode, and a grid between the cathode and the anode. The bias power supply generates a bias voltage to be applied to the grid to control a tube current between the cathode and the anode. The X-ray control unit applies a bias voltage as a pulse string for generating a constant tube current and controls at least one of the pulse count and pulse width of a bias voltage for each predetermined period.

Abstract: An X-ray tube includes: a Wehnelt electrode having a dent inside; a filament arranged in the dent of the Wehnelt electrode and configured to emit an electron beam when electricity is passed therethrough; an anode configured to emit an X-ray in response to the incident electron beam; an electrode part configured by at least one pair of electrode members, the electrode members facing each other across a path of the electron beam, a voltage being applied to each of the electrode members; a voltage controller configured to control the voltage applied to the electrode part; and a shield member arranged in contact with the Wehnelt electrode and configured to cover part of the dent by a projecting part.

Abstract: An X-ray tube includes: a Wehnelt electrode having a dent inside; a filament arranged in the dent of the Wehnelt electrode and configured to emit an electron beam when electricity is passed therethrough; an anode configured to emit an X-ray in response to the incident electron beam; an electrode part configured by at least one pair of electrode members, the electrode members facing each other across a path of the electron beam, a voltage being applied to each of the electrode members; a voltage controller configured to control the voltage applied to the electrode part; and a shield member arranged in contact with the Wehnelt electrode and configured to cover part of the dent by a projecting part.

Abstract: An X-ray computer tomography apparatus comprises a high-voltage transformer which performs the increase and noncontacting transmission of the power simultaneously and outputs a desired high voltage for causing X rays to be generated at the rotatable gantry section. The high-voltage transformer is divided into a primary-side which is provided on the static gantry section and to which the output of a frequency converting circuit is supplied and a secondary-side which generates a high voltage. A capacitor is connected to a secondary coil of the high-voltage transformer, thereby forming a resonance circuit.

Abstract: An X-ray computer tomography apparatus comprises a high-voltage transformer which performs the increase and noncontacting transmission of the power simultaneously and outputs a desired high voltage for causing X rays to be generated at the rotatable gantry section. The high-voltage transformer is divided into a primary-side which is provided on the static gantry section and to which the output of a frequency converting circuit is supplied and a secondary-side which generates a high voltage. A capacitor is connected to a secondary coil of the high-voltage transformer, thereby forming a resonance circuit.