A method is described for controlling a tube current for acquiring at least one X-ray image. The method includes performing a preview acquisition of the region under examination; determining a three-dimensionally modulated X-ray attenuation of the region based upon the preview acquisition; determining initial tube-current profiles based upon the X-ray attenuation; defining a tolerance band for subsequent real-time modification of tube currents, a maximum permitted tube-current profile being determined for which an X-ray tube of the X-ray imaging apparatus does not overheat; determining an expected value and a maximum value of a potential patient dose based upon the initial tube-current profiles and the tolerance band; measuring an actual X-ray attenuation during acquisition of the at least one X-ray image; determining adjusted tube-current profiles based upon the actual X-ray attenuation and the initial tube-current profiles; and adjusting the tube current in accordance with the adjusted tube-current profiles determined.

An X-ray apparatus is provided with a control circuit. When a duration monitored by a timer in which the device is not operated exceeds a predetermined set time, and a duration monitored by a timer in which a connected state is detected by a transformer exceeds a predetermined set time, the control circuit performs control while disconnecting the connection between a storage cell and a high voltage generation circuit, and performs control while starting the charging of the storage cell via a power socket which is an external power source. This makes it possible, merely by connecting the apparatus main body to the power socket which is an external power source, to disconnect the connection between the storage cell and the high voltage generation circuit and starts the charging of the storage cell on the basis of the results obtained by the timer. As a result, it is possible to automatically charge the storage cell by connecting to the power socket which is an external power source without relying on the actuation and the stoppage of the apparatus.

An X-ray apparatus is provided with a control circuit. When a duration monitored by a timer in which the device is not operated exceeds a predetermined set time, and a duration monitored by a timer in which a connected state is detected by a transformer exceeds a predetermined set time, the control circuit performs control while disconnecting the connection between a storage cell and a high voltage generation circuit, and performs control while starting the charging of the storage cell via a power socket which is an external power source. This makes it possible, merely by connecting the apparatus main body to the power socket which is an external power source, to disconnect the connection between the storage cell and the high voltage generation circuit and starts the charging of the storage cell on the basis of the results obtained by the timer. As a result, it is possible to automatically charge the storage cell by connecting to the power socket which is an external power source without relying on the actuation and the stoppage of the apparatus.

A method for controlling an X-ray source configured to emit, from an X-ray spot on a target, X-ray radiation generated by an interaction between an electron beam and the target, wherein the X-ray spot is determined by the field of view of an X-ray optical system of the X-ray source. The method includes providing the target, providing the electron beam forming an electron spot on the target and interacting with the target to generate X-ray radiation, and adjusting a width and total power of the electron beam such that a maximum of the power density profile in the electron spot is below a predetermined limit, and such that a total power delivered to the target in the X-ray spot is increased.

The X-ray generator includes a booster for boosting a first DC voltage supplied from a voltage source to a second DC voltage higher than the first DC voltage, at least one capacitor for receiving the second DC voltage and generating a charging voltage on the basis of the second DC voltage, a converter for converting the charging voltage into a driving voltage, an X-ray source for receiving the driving voltage and emitting X-rays according to the driving voltage, and a controller for controlling the booster, the converter, and the X-ray source. The controller calculates a cooling time required for cooling the X-ray source to a predetermined temperature or lower, determines the magnitude of the second DC voltage according to the cooling time, and applies the second DC voltage to the capacitor for the cooling time.

The X-ray generator includes a booster for boosting a first DC voltage supplied from a voltage source to a second DC voltage higher than the first DC voltage, at least one capacitor for receiving the second DC voltage and generating a charging voltage on the basis of the second DC voltage, a converter for converting the charging voltage into a driving voltage, an X-ray source for receiving the driving voltage and emitting X-rays according to the driving voltage, and a controller for controlling the booster, the converter, and the X-ray source. The controller calculates a cooling time required for cooling the X-ray source to a predetermined temperature or lower, determines the magnitude of the second DC voltage according to the cooling time, and applies the second DC voltage to the capacitor for the cooling time.

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.

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.

Methods and systems are provided for dual energy imaging. In one embodiment, a method comprises controlling an x-ray source with a first voltage to generate x-rays at a first energy, controlling the x-ray source with a second voltage to generate x-rays at a second energy lower than the first energy, and controlling a current of the x-ray source to peak above a target current when a voltage of the x-ray source is transitioning from the first voltage to the second voltage. In this way, the duration for transitioning from the first voltage to the second voltage is reduced, thereby enabling faster voltage switching of the x-ray source, improved energy separation in acquired projection data, and improved image quality.

Methods and systems are provided for dual energy imaging. In one embodiment, a method comprises controlling an x-ray source with a first voltage to generate x-rays at a first energy, controlling the x-ray source with a second voltage to generate x-rays at a second energy lower than the first energy, and controlling a current of the x-ray source to peak above a target current when a voltage of the x-ray source is transitioning from the first voltage to the second voltage. In this way, the duration for transitioning from the first voltage to the second voltage is reduced, thereby enabling faster voltage switching of the x-ray source, improved energy separation in acquired projection data, and improved image quality.