A management device (70) includes a degree-of-wear detection unit (72) for detecting a degree-of-wear of an emitter from a voltage, a current, or an energization time of the emitter, an adhesion amount estimation unit (73) for estimate an adhesion amount of a conductive material onto an envelope based on the degree-of-wear of the emitter and a relation between the degree-of-wear of the emitter and an adhesive amount of the conductive material onto the envelope stored in a storage unit (71), and a creeping discharge estimation unit (74) for estimating the probability of occurrence of a creeping discharge based on the degree-of-wear of the emitter, the relation between the degree-of-wear of the emitter and the adhesion amount of the conductive material onto the envelope stored in the storage unit (71), and a relation between the adhesion amount of the conductive material onto the envelope and the probability of occurrence of the creeping discharge onto the envelope stored in the storage unit (71).

A management device (70) includes a degree-of-wear detection unit (72) for detecting a degree-of-wear of an emitter from a voltage, a current, or an energization time of the emitter, an adhesion amount estimation unit (73) for estimate an adhesion amount of a conductive material onto an envelope based on the degree-of-wear of the emitter and a relation between the degree-of-wear of the emitter and an adhesive amount of the conductive material onto the envelope stored in a storage unit (71), and a creeping discharge estimation unit (74) for estimating the probability of occurrence of a creeping discharge based on the degree-of-wear of the emitter, the relation between the degree-of-wear of the emitter and the adhesion amount of the conductive material onto the envelope stored in the storage unit (71), and a relation between the adhesion amount of the conductive material onto the envelope and the probability of occurrence of the creeping discharge onto the envelope stored in the storage unit (71).

A apparatus may include a power supply to receive a first voltage potential and output a second voltage potential that is greater than the first voltage potential and a cathode emitter to emit ions in response to application of the second voltage potential. The apparatus may also include a step down transformer to receive the second voltage potential and output a third voltage potential that is less than the second voltage potential. The apparatus may also include a heating element to, in response to application of the third voltage potential, heat the cathode emitter and lower a work function of the cathode emitter.

A apparatus may include a power supply to receive a first voltage potential and output a second voltage potential that is greater than the first voltage potential and a cathode emitter to emit ions in response to application of the second voltage potential. The apparatus may also include a step down transformer to receive the second voltage potential and output a third voltage potential that is less than the second voltage potential. The apparatus may also include a heating element to, in response to application of the third voltage potential, heat the cathode emitter and lower a work function of the cathode emitter.

This application disclosures a method for calibrating filament current data of an X-ray tube. The method includes obtaining a first value of tube current to be calibrated and a value of filament current to be calibrated, the tube current to be calibrated and the filament current to be calibrated corresponding to a first calibration point; performing an emission operation based on the first value of the tube current to be calibrated and the value of the filament current to be calibrated; determining an actual value of the tube current during the emission operation; determining a difference between the actual value of the tube current and the first value of the tube current to be calibrated; and calibrating, based on the difference, the first calibration point.

This application disclosures a method for calibrating filament current data of an X-ray tube. The method includes obtaining a first value of tube current to be calibrated and a value of filament current to be calibrated, the tube current to be calibrated and the filament current to be calibrated corresponding to a first calibration point; performing an emission operation based on the first value of the tube current to be calibrated and the value of the filament current to be calibrated; determining an actual value of the tube current during the emission operation; determining a difference between the actual value of the tube current and the first value of the tube current to be calibrated; and calibrating, based on the difference, the first calibration point.

Provided is a miniaturized X-ray tube including an extractor and provides a miniaturized X-ray tube including a filament that emit electrons if a voltage is applied, a base having two filament through-holes for fixing the filament and for connecting power to both electrodes of the filament, a cylindrical extractor in close contact with the base and surrounding the filament without being in contact with the filament, a cutoff voltage providing unit configured to apply a cutoff voltage between one electrode of the extractor and one electrode of the filament, a body that is formed of a ceramic material, surrounds the extractor, and includes one end in close contact with the base, and a target that is connected to the other end of the body, receives the electrons emitted from the filament, and emits X-rays.

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 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.

Computed tomography (CT) imaging system has at least one processing unit configured to receive operator inputs that include a modified system feature and a clinical task having a task object and also receive operator inputs for determining a task-based image quality (IQ) metric. The task-based IQ metric represents a desired overall image quality of image data for performing the clinical task. The image data acquired using a reference system feature. The at least one processing unit is also configured to determine an exposure-control parameter based on the task object, the modified system feature, and the task-based IQ metric. The at least one processing unit is also configured to direct the x-ray source to generate the x-ray beam during the CT scan, wherein at least one of the tube current or the tube potential during the CT scan is a function of the exposure-control parameter.